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SeanBZA
Scott Manley
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Comments by "SeanBZA" (@SeanBZA) on "Scott Manley" channel.

The thing about the photography side was that the ultra fast gas switches were not used to fire the Xenon flash, which, for the technology of the time, was easy to do, using a simple high voltage pulse that ionised the gas in the Xenon flash tube at the cathode end. The big thing was they had to actually only fire the tube for a very brief period, so as to only have this very short burst of very bright light, so that the motion of the aircraft would not blur the image. Thus the need to develop a device that would be able to turn on very fast, and also handle a massive current pulse, so as to dump all the charge in the capacitor bank used to provide energy to light the flash tube, so as to drop the voltage across the flash tube (at this time it would be dropping from the 400V or so initial voltage, to the cut off point of around 60V, where the tube itself would start to slowly cut off due to the arc voltage being below the voltage needed to keep it on, slowly being in the order of tens of microseconds) to close to zero, and thus ensure it has a sharp cut off. Most devices at the time would either not last more than a single use, or would not have the fast response needed. This device was the original gas thyratron, and the need for fast ones meant they made them with a hydrogen gas fill, with early ones filled with neon being both slow, and too low an operate voltage. Hydrogen gave the needed high voltage stand off needed, and because it is light, it also ionised very fast, giving the very rapid current path build up, in the order of nanoseconds from fully off to fully on. This has led to them being now an export controlled device, and to this day an item that is still made, on the original tube lines, by some specialist companies in the USA, as the US military needs them for operational parts, and, because of the hydrogen gas fill being able to penetrate almost all seals with ease, a part that has a very limited shelf life of around 2 years, before you need to either replace or rebuild it. Neither are cheap either. You can test it at lower current, and do all your qualification at this level, as full power operation you only have around 5 uses, before it degrades to the point it is no longer usable. Selling them is ITAR restricted, as heavily as any part can be, because of the one use case, so there have been a few attempts to steal the technology. These days you still find it hard to get the same power delivery with small volume, it really is a part that is perfect in it's application. But you can do it, with modern high power semiconductors from specialist companies, with corresponding exotic semiconductor compounds, and prices that make the gold used to plate them the cheapest cost in production. Incidentally the bridge wires also underwent massive changes, from simple thin wires, to the modern ones, mass produced using semiconductor wafer processes, to make thin film metal alloy strips that are precisely controlled in shape, composition and dimension, so that all of them are as close to atomically identical as possible. The difference in timing between them is in the order of picoseconds, they are that identical.
352
Delta, predated the shuttle, survived the shuttle, outflew the shuttle, and worked out overall cheaper than the shuttle.
258
Funny enough, I did once jump start a helicopter, which had a battery that had run down due to the DC bus being turned on overnight so the security guards could use the aircraft radio to listen to broadcast FM. Helped that I did my apprenticeship on that model, and knew the entire electrical system, and also the pitfalls that could occur with them running the battery down, and what to look for. Ground power unit and the ground power connection, start the ground power unit and power up the DC bus, and they press start. Low current, the ground support unit is designed to supply 8kA at 28VDC, and this little turbo barely made it to 400A during start, so after a half minute of idle, pulled the cable ( only way, there is no disconnect other than a sense contact on the plug), waited another 5 minutes at idle to see if the battery was not going to go into thermal runaway, it was still cold so gave them a clearance to take off back. As well used another ground support unit to jump an ambulance that had waited 6 hours for the casevac to get there, with lights on, and there had to grab jumper leads to make the link between the connector and the battery. those lights went very bright on 28V instead of 24, and that ammeter needle did not even budge off the zero during the very very vigorous starting. As to the LRV batteries being used to fire the ascent stage probably no issue, the batteries certainly were the same chemistry, they used a similar enough voltage. The major issue was the disconnection, as the LRV batteries would stay behind, and the ascent stage needed power to keep the valving operational, so they designed the systems to get you power from an alternate set of ascent batteries if the main ones failed, but use batteries on the ascent stage. You could not have kept the mass centre stable if you used the LRV battery pack and carried it with, no real space to place it (otherwise they would have had equipment or battery pack there already) and also it would move the mass centre from the engine bell outside the ability of the RCS system to compensate for the eccentricity. Silver Zinc batteries are heavy, and are only used in space applications because they are so reliable and tolerant to abusive temperatures and charge and discharge use, unlike the modern lithium chemistries. Thus you can have a smaller battery pack for the same high current draw, and not have to worry too much about it cycling from -100C to +200C every orbit.
57
@-yttrium-1187 But also equally hard to cool, as only radiation to carry it away, and you need massive thermal shielding to provide thermal barriers.
46
@codymoe4986 Also was a single use vehicle, and definitely was not going to be used again, even if you did manage to find it.
46
Also a lot of different propellant types, based on if they are derivatives of ICBM designs, or are made from designs appropriated from other countries. All controlled centrally, but they obviously are all different to see which ones are going to be best at getting reliability. My guess on the dual crater is that this second stage still had a satellite on it that was not disclosed, and it failed to release for a reason, and thus was still attached as it was approaching, and the tumbling just before impact tore the payload apart to make the second crater.
45
With all the things about these hypergolics, they are still the least dangerous ones that are in use, the more exotic ones proved to be a little hard to handle, so the ones that merely dissolve you are the ones in use.
37
You can see a skirt on the base, so likely it was lowered onto the stand and sat on the skirt. Then they likely used multiple clamps to hold the skirt to the stand. Most likely is that one or more of the clamps either were not tight, or the bolts had been machined undersize, leaving not enough thread engagement, or only a part of the thread was engaged. Then the thrust snapped those, and the others that held tore the skirt loose, which accounts for the damage, as that skirt likely also damaged the engine bells as they rose up past the stand centre, and either bent them or fractured them. Bent ones got hot spots that later on failed, and the cracked ones were losing lots of cooling fuel till the uncooled areas melted away, and caused that engine to shut down because controller saw dropping thrust. Then the remaining engines were slammed to 110% to compensate, and this extra stress meant that one of the dented ones split open, and the parts blown off into the plenum damaged piping and such on others, and also likely destroyed the guidance controls, as it did not recover. Thus the big black cloud of burning fuel and hydraulic fluid, and bits of engine rich exhaust. Controller saw thrust was dropping on those engines, or pressures were dropping and flow rates were running wild, and shut off them, trying to correct attitude with the others by throttling them back and trying to correct with steering the remaining engines, and then it went horizontal. It probably detected a launch abort, and attempted to blow the destruct charges. Of course, seeing as this is a test firing, those likely were not fitted, just had the test bypass units in place, to pass the regular self test cycle.
29
@thetimebinder Granted not man rated, but better overall safety record than the shuttle anyway.
27
Also a part with a very finite life, as it is designed so that it is very close to it's elastic limit in normal operation, so you have a very limited number of cycles before you run the risk of it failing from fatigue. Needs very special care to keep it from having any extra stress from installation, so likely is a bolted on part as well, not welded, especially in an application like this where the margin between operation and failure of the main structure is so small. Whoever is making them probably has a few dozen per batch, and tests half to failure to ensure the rest are going to be within the required range of operation.
25
@Jonascord Did the same, they burn really fast, he got a single puff out of it before it was down to the filter. With LOX remember not to use shoe polish, it may not be the best thing. Was filling a LOX tank in the bay, and there was a snake in there. Broke it, as it fell out of the gloves when I grabbed it, and on landing on the floor at cryogenic temperature it broke into pieces.
23
A lot of very bespoke computer designs were around before the microprocessor came along and guided them into a few very rigid areas. Especially those that were made from discrete logic, and where the designers went and made it with instructions they needed, and little more, and where your software and hardware were very tightly bound. Designed for the purpose, and then made to be as compact as possible, with, in that era, as few transistors as possible, because they were both very expensive, and also not as reliable as diodes. So you had a lot of diode logic, with transistors scattered around where absolutely needed, to act as inverters and regenerate the logic levels. Many of those designs were translated into early IC based systems, and they often used EPROM to do complex functions, like a lot of glue logic, and also to store tables used in math, so as to simplify multiplication, giving you the ability to have 2 5 bit numbers be multiplied together, to give an 8 bit output, in a single clock cycle. Used a 2708 1k EPROM, holding the decimal number table, and allowing you to do multiplication in a few cycles through the table per digit.
22
I remember being in an aircraft that used that overshoot once, rotated just about the end of it. Hot, altitude and a full load of fuel on board. Flew in ground effect for a while as well, till those 4 jet engines had burned off enough fuel, and gotten up the speed, so we could climb. Trees were companions for a few minutes, as well as the town we went over at a little above treetop and rooftop height.
21
Bear was drugged, guess the Air Force had a bear problem, as normally they did these sort of experiments using a full grown pig, as it very much approximates the human body in accidents. Normally after the test the pig has an invite to the BBQ, as guest of honour, after the autopsy.
20
Why do you think the Hubble mirror was flawed, focus length was to the original spec of 270km and not infinity.
19
Build there so it is convenient to have the workers close by, and also the test engineers can stay at a local hotel, and enjoy the city, not have a 4 hour commute each way every day.
16
You also get inadvertent jamming in built up areas, with harmonics of thousands of cheap poorly filtered power supplies and LED lights, all creating a much higher noise floor in the area, so that the initial lock of a GPS takes a long time. I often see that, startup time can be up to 10 minutes, or you have the GPS time out, because it cannot get a lock, yet when the power to the area is cut you get a lock within a minute just from the lower noise floor.
16
@aBoogivogi The Soviets had somewhat less good results, and have had a good number of failures as well. most memorable was the Kursk, destroyed by a leaking torpedo, a well known issue, that they had ignored as a possible cause for concern, because the torpedo tube was designed to contain the blast with the inner door closed. Too bad it did blow with the inner door not fully closed, because of a poorly designed or made electrical connector, another well known issue, combined with a catalyst in the tube, otherwise known as rust.
15
To be fair, a lot of fighter jets are aerodynamically worse than a brick, but fly because even a brick can fly, if you strap a big enough engine to it.
14
Not likely much, cut to appeal to the average market, not any with the ability to think beyond Ooh shiny ball.
14
Also your mobile phone absolutely depends on GPS, just to provide an accurate clock that allows for the time slots per device to be as tight as possible, allowing for maximum data throughput, but also to provide an accurate clock that allows the base stations to be able to use QAM256 to get as much data through per signal transition, using the GPS clocks to generate a very precise, as in down to single parts per billion accurate, clocks for the base stations, to do this. No GPS, no clocks, and very much degraded phone service, as the towers need to fall back to a very coarse clock provided by a heated crystal, good enough for one part per million, but now resulting in a much reduced data rate per device.
14
Probably will need around 5 times the delta V to deorbit, though of course that is also something you can do with just using a large ion engine, and a lot of fuel for it, with power being provided by the on board satellite arrays, as you would need minimal power to charge batteries as they only will have to provide orientation and 45 minutes of low draw during the night passes, and will not really need to power much in the environmental system with no people on board, do you can simply shut down and drain a lot of the systems to safe them, then keep the bare minimum like attitude control, computer systems and circulation to even out temperature. You can close all the airlocks as well, and that will reduce the need further for power. Just your booster bus will need some redundancy power wise and control wise, probably like the shuttle, 5 general purpose computers to run it, and likely some solar panels to augment power, and also a lot of RCS fuel for attitude control. Easy to do if you have 2 of them one each end, and thus taking turns in providing thrust in orbit to raise it, and slowly over say a year getting up to a relatively open orbit. To get past LEO will take about as much ion engine fuel though as what you can fit into a Falcon 9 heavy payload fairing, as a single large cryogenic tank, so you probably will want to make the tank emulate the fairing and take it to orbit, it will save weight using the fairings as structural and insulation instead of discarding them. Would say 4 F9 heavy launches will get the lot up there, with 2 separate orbit lifter units and tanks, and then probably a final set of spacewalks to provide connection to them so they can share fuel and power
14
@flymypg Antonov had that yesterday, probably seized compressor bearing and the fan decided to take a holiday, wiping out the AC electrical buses and the instrumentation and hydraulics, so the pilots had to do a really heavy landing with no brakes or spoilers. Tough aircraft frame though, it did not fail until after it had left the runway end and was ploughing the frozen field.
13
@big0bad0brad As you have to service them every 6 months, it is not an issue, you would replace them and refurbish them every second cycle, long before they are possibly going to fail. Remember you are talking about radioactive things, and you do not just put them in a box and store for the next decade or three, like conventional explosives. You have to keep them in a 6 month maintenance cycle or they simply do not work. Anyway your ignition package is likely to need replacing regularly, simply because it lives in a very radioactive environment, and you are going to swap out the explosive pack in that 6 month cycle, because there will be degradation from the neutron bombardment that makes for all sorts of unstable new compounds in it.
13
Simplest would be to use those airlocks throughout the station, and simply take modules out of service, and use a Progress to control the deorbit of the module or pair of modules, so that you gradually get a smaller station that is easier to control for the last unmanned missions to go up and automatically dock, so they can then have a full fuel load for control.
12
turpentine trees are really flammable, in that the green leaves will burn very easily. We used to use turpentine tree branches and green leaves as firelighters, taking the thin fresh growth green branches and leaves, and using a layer of them, along with old newspaper, to light the charcoal of the fire.
11
Lithobraking was done, due to them forgetting to make sure the software would work in simulation.
11
@big0bad0brad Because the internal pressure is critical, you would have to have an external chamber with gas at the right low pressure to have any hope to keep it correct, and that container would also leak hydrogen even faster.
11
The plans are available, along with the patents. The big problem is not making one, but living to finish assembling it, as the least of the worries you have is radiation, the metals involved are all by themselves a pretty toxic group, and the radiation they give off is rather hard to conceal.
10
@Keldor314 Yes multipath reflections and diffraction off of the sharp edges of the mountain peak, which means the signal appears to be shifted in time with the reflection off the other side, and also takes longer with the diffraction, so the GPS receiver calculated position is wrong, but to the GPS it is still a valid position on the internal map it has of the area.
9
@dylanwinn3 Volunteers out of the prisons, who were offered free passes of remaining sentence if they did so. None were told it would likely be fatal for them, and they were run through till they could not go any more. Plenty are no longer mentioned in any records. Luna team would have been better off result wise if they had pulled old fighter plane tech out of the stores, and used the tube based avionics there instead, with the simple magnetic amplifiers and hollow state electronics, which would survive the high radiation a lot longer before failing. Yes you need to bring along 400Hz generators for power, but those are common enough, at at worst you could simply grab one of the helicopters, and run it as a power supply.
9
@GrogAdHoc Load paper tape, enter 5 command bootloader on the front panel switches, then press start on the tape reader, and wait for the terminal to give a ready prompt. Then you can load the actual operating system into memory from the mass storage device. Then you can start the GUI and use it.
9
@NicholasRehm Not likely, just that the computer systems are probably only going to be Intel 386 based at best for the core of the ISS, as those are currently the only, aside from some Motorola and MIPS parts, of around equal speed and complexity, parts with space grade reliability available, Laptops and other stuff they handle by having multiple devices, so a radiation induced failure is not terminal, and they do repair a lot of them by swapping parts around common devices. Remember most of the control software is either running on redundant hardware with error correction, and no method to update it, or is running older versions of operating systems that are different enough that your common malware will not run on them. However nothing stopping somebody from doing a Stuxnet style attack, though that requires intimate knowledge of the systems and how they are connected.
8
Not really, the field would very likely also affect operation of the craft itself, so much simpler is simply to have light mass shielding, or something that you need to take with do it as well. Most likely thing is that there will be a water tank that is also a shelter, with the water acting as shield, and also the required food rations can do the shielding as well. Probably there will be a thermal shield used on the spacecraft that does triple duty, acting as sun shield, and also as a micrometeorite shield by having multiple thin metallised mylar layers, and acting as a radiation shield by allowing the high energy particles to impact it, and the inner layers handling secondary emission, then the spacecraft hull itself acting as a barrier, with the rations packed so as to absorb it's secondary emissions. The dried waste would also be packed back into the same spot, so the shield gradually changes from food to poo as they travel along.
8
No, low background steel is still a problem, unless you go to the expense of taking iron ore and using a brand new blast furnace to refine it, and not do like most common operators do and add scrap steel to the furnace as extra charge. Thus you still need to get the old steel, and vacuum melt it to keep the contaminants out, then cast it into a mould and machine it. Still enough residual radiation from that old atmospheric testing, plus the releases from the assorted nuclear accidents, that you will want a old steel shield, especially if you are looking for very low levels of radiation, and need to have as low a background as well.
7
All those reactions use cheap catalysts, like pure iron, or iron oxide. However they also need those catalysts to be ultra pure, so the iron used to make them has to be specially refined, to remove all of the other metal contaminants that normally are added to improve strength and ductility, as they can also act as catalysts and make unwanted side reactions.
7
@AnonymousFreakYT Less room than that, imagine living for 2 weeks in just the front seats of the original Mini. Wearing boots and a crash helmet, along with full motorcycle gear, including gloves.
6
Do not forget the provenance of that film the Soviet luna orbiters used, being actually US made film that they "got" from the USA by a rather unusual method.
6
Yes, but there is a big chunk in the middle of the throttle range that is not good to stay in long, you transit fast, because there you will have instability.
6
Biggest impovement was the patch antenna, which placed most of the receiver filtering at baseband into a single precise ceramic puck, that not only was the antenna with a wide acceptance angle, but also the front tuned circuits and selectivity, and with it being a very high Q filter to reject out of band noise as well. Got rid of half a rack of cavity filters and amplifiers, that you needed to keep at a constant temperature, and also a good chunk of power needed for all the amplifiers and temperature control.
6
Have to be better than a space suit, that only has to withstand direct sunlight and vacuum for a while. The suits need to survive conditions like that in the Jovian upper atmosphere. Jupiter's colours come from having an atmosphere mostly made from all sorts of nasty nitrogen and hydrogen compounds.
6
Well, it would devolve to VFR from 1924, when pretty much the instrumentation was the pilot and his eyes. Would suggest a good upgrade would be to add in a standby compass, standby altimeter and a standby airspeed indicator, as a minimum flight instrument list, that will help in case the ancient Garmin decides to brain fart, as they are well known to do with some combinations of a complex map and some locations. All 3 can be bought used, and simply sent in for a certification, and then the standby compass will just need to be swung with the aircraft in flight ready configuration, to adjust the 8 cardinal point compensation screws. Memories of 3 hours in the swamp, in the compass bay, acting as the intercom link between my instructor melting in the rear, and the 2 pilots and flight engineer melting in the cockpit. After the 10 full circles to get the newly repaired fluxgate sensor aligned perfectly, the others decided to drive back on the tow tractor, while I elected to stay on board, and fly back with the 3 in front. They still had 3 hours of fuel left, but only needed an extra hour to complete flight hours for the month, so they did a little trip out to sea, and there I got to see them doing an aerobatics show with the 16 ton helicopter, doing all the daring moves, that are limited to 0G to +3G, that are permitted with a helicopter when you want to avoid chopping your own tail off, or having the main rotors separate. Sitting in the door, hand through the strap, and looking up at the ocean above me, and the sky past my feet, as they did a few barrel rolls around 1km offshore, with the closest place to swim to being the offshore oil platform. 2 very happy and now cool pilots.
6
@5Andysalive The saying was in Apollo you were in a space craft, but in Gemini you wore a space craft.
5
All the Helium you have on the surface of the earth is also not primordial, it came about as the result of alpha particles grabbing 2 electrons to become stable.
5
More like the last part frame was corrupted by the digital signal processor and transmitter becoming fine gravel mid frame, with likely the last image still busy being DCT transformed in RAM by the image processor. Probably you have a part bit sequence that was received, but, because it was rejected due to failing the CRC check (for some reason) as the final part of the last scan line. The lines and such yes are probably partly due to varying composition, of what is basically a cloud of pebbles, dust, and well chilled assorted ices, suddenly being shocked, but I would say a good part is also composed of bits of spacecraft that has pressurised liquids and propellants reacting for a brief moment as they were scrambled and mixed together, along with batteries that briefly were free to express all energy as well.
5
@solarcheese Well, the main issue I can see is that you would first have to find the remains of the barrel, because it would probably impact the ground at around Mach 10, and, assuming it survived more or less intact, that is more than enough impact energy to bury it at least 50m into solid granite. More likely though the barrel, assuming you used a standard steel 44 gallon one, would ablate through at around 100km altitude, leading to the oil leaking out, and then the remains of the barrel being torn apart by aerodynamic forces around 60km up as it hits atmosphere thick enough to register on regular gauges.
5
@PsRohrbaugh Plus possession of such a jammer, or at least using one near an airport, will have a few government agencies find you, and have a very long and pointed talk to you. Ask the truck driver who did that near a US airport, because he wanted to jam the GPS tracker on his truck, so he could have some off time on the clock.
5
No problem about the light, your smile was light enough Scott.
5
No need to actually look for a new processor, simply use one of the more modern Space rated products that are still available in large volumes. Intel still does supply the 386SX and DX in space rated packages, using a SOS technology, which is a more modern and faster part. Yes likely just a few thousand fully tested dies in CA storage, ready to be packed and tested to order, but still a part likely to be around for the next 50 years. Buying an original Mostek or Rockwell part is still there, not robbing old equipment, you just pay Rochester Electronics to take a wafer and pack it, then test the result and get the qualification, they specialise in old silicon, buying up old wafer stock and storing them essentially forever. You need it you pay the price they ask, and smile. With gritted teeth, they price just below replacing the whole lot entirely, but still cheaper. However the 6502 is, thanks to it being out of copyright, one of the more prolific processors around, available as an IP core for pretty much all FPGA and ASIC families, as it is simple, very small and very functional. You have one in every hard drive, used to load the firmware into the ASIC and FPGA units that do the actual work, and it also then is a slow processor, but tiny one, that does housekeeping and monitoring of the hard drive, so that the drive can retract heads and shut down gracefully when power is removed. With only 64k of memory you can make half the fixed ROM, for bootloading the rest, and the rest RAM to handle memory, with a little bit of IO somewhere to feed data out to the rest of the array. Simple to implement in silicon, free assemblers and compilers, and no money to pay for a per unit license, it is very common to have it embedded all over in equipment as a processor doing something.
4
No, that was Thiokol boosters. The USSR was constrained by needing to fit onto existing proven hardware that had limits as to dimensions and mass capability. they needed to have it work due to both material restraints and also engineering personnel restraints, so reuse of existing stuff and simply using more duplicates was the solution.
4
Neutron star mergers, best viewed from at least 1000 light years, especially if you want to be able to talk about it later on.
4
@davidharding1732 Another read as Bomb tech outranks all at a run.
4
Still used these days, though the case is smaller, lighter and it is a lot more expensive to repair when it fails. But for the mass cheap, easy to drive and very rugged, and it does work.
4
Redundancy, so that you still have one if the other fails. No doubt they eventually will have a single system that is a tenth the size, with both integrated into it, and with a quarter the power consumption. then will demand 2 as well.
4
I see they still have the original Halon cabin extinguisher there as well, just in case some of that original equipment decides to emit vintage smoke. You need the right vintage of smoke control in the fire extinguisher to put it out.
4
Probably because the toys are really highly loaded with bisophenol, and the non stick coat on the surface is PTFE applied as vapour. Both now classed as not suitable for toys.
4
Plus the material used for the walls got thinner and thinner, till they had to stop, because the craft was almost at the point it could not support itself under earth gravity. So thin that the crews who were building it had to take care not to step on, or touch the hull, as they could destroy it merely by putting a foot on the surface, and tear the skin. This would mean scrapping the entire craft, and building another, as the skin was too thin, and the joins so small, that they could not remove a panel and rivet in another, as the material would likely tear. The end material was barely thicker than the aluminium used to make cans, and just as easy to dent when not pressurised.
4
My father crashed 2 aircraft. One a Gypsey Moth during training, and the other was a Lancaster, that sort of fell apart around him over the Bodensee. All he remembered, before the 6 weeks of black, was the plane, and his parachute, being on fire, and him telling his crew to bail out. Austrian nurses told him they picked up his body in a snow bank under a pine tree, and thought he was dead till the coroner found a heartbeat. Then patched him up, removed most of the broken pine tree, broken glass and shrapnel from him, and did a massive skin graft to fix the burn that covered his entire back. Basically broke almost every bone in his body, but the Austrian doctors and nurses put him back together.
4
@MattH-wg7ou Probably not calculated correctly, or they figured they could get away with it. Helped by a 6km long runway, not by it being 41C that afternoon, and bright and sunny. We did land mostly empty, part of the fuel load was transferred en route as practice for the other planes.
3
The modern way to get accurate time is a set of GPS locked hydrogen maser clocks at each location, so that the GPS signal, knowing your accurate location, and a long enough time, allows both atomic clocks to keep near perfect time with each other, and then you record the data with a time stamp and use a compute cluster to correlate the data to match each waveform to the corresponding one from the other. From that determine the delay due to distance, and solve the trigonometry. You have to sample at the carrier itself, which generates truly huge data sets, but you can use local computation to reduce the data volume, without sacrificing the time information, and once you have the data you can also average over a few minutes, to both get a motion vector compensation for the earth rotating, and also then the vector for the spacecraft moving. Before you would record both outputs using magnetic tape with an accurate clock, a Cesium atomic clock that was in a suitcase, that got flown there powered up, keeping the time from the master clock, and used to time stamp the data on the magnetic tapes. Then the tapes were flown back, and a room full of mathematicians solved the problem. Current methods rely on a high bandwidth link via the public Internet to do the backhaul in near real time, and NASA has the computer clusters to do the data handling as well in near real time as well, thanks to improving technology.
3
Another consideration is noise, as engines can be loud. Even jet engines easily will clock over 140dB in a test chamber, and rocket engines can easily go over 200dB when you are in close proximity. Loud enough to destroy concrete and tear thin steel structures, and a thing you have to consider in both the design of the engine and the test area, in that if you reflect the noise back you can destroy working engines in seconds.
3
@WakarimasenKa Don't think it is much, more designed to leave them right there, while the aggressor is desperately wanting to be NOT there.
3
Time to ask Usagi electric to translate it, as that is his actual non YT job.
3
@musaran2 True, and ASIC came out of wanting to reduce logic down from multiple boards to a single chip, to save cost and improve speed. Internally you either have basic blocks you stitch together, or have a full custom design.
3
@lawrencedoliveiro9104 This was over 20 years ago, when fabs were still all in the USA or Europe ( pre Eurozone), and yes modern ones will do semi custom fast, using existing stocks of sea of gate wafers. A step up from a FPGA, making it both cheaper and slightly faster, as you take your existing FPGA code and they translate it into a connection layer for the metal steps on the die. You get a fixed design, and no need to have a memory chip loading code, so it is now a place and use part, no programming needed.
3
No, likely got scrapped, along with the rest of the Apollo era hardware, or taken apart and used for other projects.
3
They went for making composite explosives with controlled density changes in the bulk, so as to make the lens intrinsic in the material, not make it out of segments. More complex in production, but you can test them more easily as shaped charge sections, and then very easy to assemble. Still needs the precise control of detonation though, and you can easily disable them till firing time using a simple mechanical switch, that adds a delay to the one section of controlled time cable.
3
Well simply because they are rare, and there are not exactly a million cameras on Mars capturing video 24/7/365, only the odd camera on a spacecraft that orbits, taking a complete pass every few days for the low resolution, and every few weeks to months for the higher resolution imagers, simply because they are scanning with such a small aperture camera to get that increased resolution. 99.999% of the meteorites that hit earth smaller than 20kg are not recorded either, simply because they burn up out of view, or nobody looks at the footage, and only the bigger pieces actually make it down and leave any mark, so likely 99.99% also are never going to be found either. Big planet, small rock, and nobody knows when or where one will hit.
3
Probably constrained by either production plant size, or by the control system to be able to control it, with only a single engine or three at the base, long and narrow to get the stability easier to handle, without a complex computer system on board. Narrow as they had to weld the parts together, and thus were likely limited by the diameter the horizontal lathe they used to machine the parts could handle in the rotating section.
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@DrDeuteron True, but the decay products are not quite as benign after a while, as you get into the longer lived decay products, that are going to emit gamma radiation at some level. But the RTG would only have the core loaded just before final mating to the lift vehicle, so it is inert, aside from some testing during construction, then the fuel pellets are removed and placed in a cooling unit. But even then you can stand next to it for a few hours, as the shielding is very effective, and it also has to survive reentry at maximum velocity in case of a failure of the launch vehicle, and also explosion on the pad. That is why those RTG units are normally deployed on an arm, both for radiating heat away, and to keep the low levels they emit from interfering with other instruments, so have it far away, and calibrate it out.
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Well yes, the currents involved are minuscule, and the price really puts them in the "we got a budget that is not a worry, and we do not want a battery that will leak ever" camp, and the main use is as memory back up, as it really can only supply 100nA of current, so most uses are as standby power source for memory back up, where you need to first make sure your memory uses less power. Consider these batteries in the forms normally seen, DIP24 ceramic package, can be shorted out merely by a fingerprint on the board allowing enough current to flow, and you typically also use ultra low leakage capacitors (PTFE dielectric, none of that rubbish ceramic, electrolytic or tantalum capacitor will do) to store charge to allow them to deliver a current pulse for other applications. Yes you can make a clock that will run forever off them, though you will find it hard to find a foundry to make the large dimension IC to get low leakage, and a display will similarly have to be specially made, probably both will be a SOS (silicon on sapphire) structure, with the LCD laser sealed after filling with the fluid, to keep it from degrading. Might be done for a $500k watch, because for sure the mech will cost more than making the case out of platinum iridium alloy.
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@RayO72 Well, remember that if it was not for poo you would not be here, as that is the part of recycling that makes a field fertile again.
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@solandri69 Most likely poor maintenance, they painted over the cables time and again, and you will probably find they trapped water in the cable, which led to corrosion cells and failure. The cables likely were made from hot dipped galvanised strands, which eventually had the zinc erode off, exposing enough steel to make galvanic cells inside the cable. I would say the design flaw was not in having enough cables there, so that you could safely remove half of them every 5 years per tower to replace with a spare set, and those removed went off to be unwound, serviced and inspected, and then greased, reassembled and recoated for the next tower rope cycle. 10 years would be plenty of time to find weak strands and remove them. Yes you would probably be splicing in repair sections every time, making the cable thicker in parts, but they would still be more than capable with that. That the initial cable failed at the poured zinc plug indicates it was very likely badly corroded inside from neglect, as that section is the one most protected cathodically, but had plenty of water ingress to corrode the inner. Likely all the lanolin applied during manufacture was long gone, and had never been replaced. Not that those were highly stressed cables, only a static load, no real dynamic force and no real bending. There are mine lift cables that are kilometers long, used dozens of times daily, that are probably older than those, but they also undergo regular inspection and lubrication cycles to keep them in operation. There are plenty that the cable weighs more than the entire telescope aerial steel structure, just in the cable alone.
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@nikkismith8750 Not really, but you do get digitisers that will actually work at those bands directly, or with minimum downsampling. Enough bandwidth to get the data, and also the clocks are common these days for cellular towers, as they also use the accurate timing so as to coordinate all transmissions across an area.
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Plus the studios will absolutely use poor viewing to screw them over, citing the poor numbers to make their profits bigger, and cutting all other takes. Remember they set the profit goals, and if it is not reached they simply take all the profits, and the writers and actors get told sorry no money.
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That aluminised fabric is also used to make bags, which hold stuff sensitive to thermal damage, and they work well to keep the contents at a reasonably stable temperature. I use the old bags, which are very big, as camping blankets, as they are easily big enough to cover you, and after 5 minutes you are very warm inside from the reflected body heat. Normally a ground sheet, one on top of that, a blanket or thin foam mattress, then you, a blanket, and another on top is a perfect way to stay warm even on the coldest night. They take up little space when folded up as well.
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I would guess the major reason for lack of proper guidance is because the computers and controls are in the second stage, and the first stage is mostly just sensors and actuators, to save mass in not having 2 guidance blocks. Simplest solution would be to put only a small low mass battery and controller there, to just turn the booster around and fire the main motors till empty, or at least be able to receive a deorbit burn instruction the next pass, and then scrub enough energy to land in the Pacific in 2 orbits. Would need to have the extra fuel and oxygen, plus also the ability to relight the core engine at least twice, first time to drop down a lot, and the second to finish, after drag has been calculated from the timed burn, then probably 2 orbits later get an updated firing time and duration on the remaining fuel. But this needs extra fuel to be carried, and the motors might not be able to restart. Otherwise just a big drag parachute to make it come down very fast and calculate the drag to make probability such that it will land in the ocean. They are just hoping that 70% water is good enough, and the 1% that it lands in China itself is fine for them, as the chance of hitting the launch area is very small.
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@scottmanley Yes, though the film was from Kodak, who had developed the method of producing it, for another also top secret mission, that also involved aircraft recovering the film. Later on everybody got to use this film process, as it become a huge commercial success.
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Very likely a solid propellant, like the one used in the SRB of the space shuttle, though burning with a much lower chamber pressure, so making a lot of excess carbon soot. Basically rubber with some powdered metal in it, and blended with some oxidiser chemical, then cast into a slug.
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@ Built stronger than a flight recorder memory capsule, and going to survive re entry thermal stress much higher than earth re entry, it might still have intact seals when recovered as well, so if it is found in shallow water under 1km deep it will likely have survived.
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@lawrencedoliveiro9104 To run a run of them, using existing masks, the quote came to $10 per transistor, with a lead time of 18 months, and a minimum order quantity of 100k units. I needed 2, so went through the pain of putting in the paperwork, to have a common part substituted for this obsolete superceded transistor. The 100k 18 month lead time though is pretty much industry standard, unless it is for something like a sea of gates ASIC, where you only pay for the final metal mask, and run off a existing batch of nearly fully made wafers, where you will get 10k units, 100 wafers, one carrier full, run with your mask, processed and packaged for you. Make sure you got it right, because they only will do a basic wafer test to see if it responds to signals, and is not shorted too badly. Then it can be as low as 6 weeks, though you will pay.
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Making an engine that uses elemental fluorine is going to be hard, seeing as you will have to make a pump that can handle the volume, and last long enough, as you will be having a race between running out of fuel, versus running out of engine. These will be rockets with engine rich exhaust even running perfectly, let alone when they get upset. Plus remember bulk fluorine liquid will burn things you think are non flammable, sand, asbestos, water, steel, aluminium, unfortunate people downwind...... now think of the thermal shock in the first combustion chamber, and that whatever you use for injection of the lithium will be dissolving in the hot liquid, and whatever you are using to bring in the fluorine will be doing the same. You probably will also not want to use pure lithium, rather a lithium sodium alloy, as those do have a lower melting point at least, and with Gallium you can get it low enough to use ordinary steel alloys as the tank.
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@michiganengineer8621 And remember there are flourine compounds that are even more reactive as well, FOOF comes to mind, and that wonderful book Ignition!
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I know of a large industrial plant where water built up in a compressor air tank. Nobody noticed till it got high enough to start to get in the outlet piping. Large air demand at the far end of the plant, so a slug of water was entrained in the pipe, and went along this mostly straight pipe to the far side. Near the end of the run there was another part of the plant, so this large diameter air pipe had to make a detour around this even larger piece of plant. Turns out the slug of water did not want to make the turn, and snapped the elbow off with the impact on the elbow. The plant was closed for a while while they were doing repairs, and also making sure that there was more than one person responsible for checking the automatic drain valves had not malfunctioned, plus adding water level alarms in the compressed air tanks.
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Bonus advantage of stainless steel is that it is so easy to recycle as well, unlike carbon fibre which pretty much will end up as landfill or will be burnt.
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@BBDoesTheThing You will want a high mountain on the equator for this, so the only place is Kilimanjaro, which is almost exactly on the equator, and high enough to make a difference. 5.8km above sea level near the peak will give a very large loft, reducing the energy needed by a good amount, and there is 5km less atmosphere to burn through. Also close to the coast so you can have a semi safe abort area, though this is one of the more congested shipping areas, but the lanes are defined. Only issue is the politics of the region can best be described as "complex", at a minimum.
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Well Apollo showed that with the lightning strike that dropped the CM offline, while the instrument ring on the third stage was supremely unconcerned. Switch SCE to Aux, to reset the power supply that tripped out from the transient. Hot enough from LOX kerosene to ionise air, just this is a whole magnitude worse, as you now have metal ions in the exhaust as well, not just carbon ions.
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That deorbit for the ISS will probably be using a Heavy, likely the outer 2 doing a RTL, and the centre stage being stripped down and expended over the Atlantic, or kept on long enough to have it also hit that south Pacific spot as well 45 minutes after launch. Keep throttle down during boost, so that it is still firing at the outer unit MECO, and it should have more than enough to get the dragon in the right orbit, and still have enough fuel to brake and do a reentry over the Pacific with good accuracy.
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@salerio61 Yes, but the local master stations will also use a Cesium or Rubidium clock, which is slaved with the GPS to provide an accurate local time and frequency, which will be shared by the local cells. But the local stations all will ultimately have a clock derived from a GPS receiver somewhere local, which is at a precisely mapped point, used as a reference marker for all timing in the area. Depends on cell density just how big an area is covered by each one, at least large enough that the coverage to the other GPS equipped stations is under the error budget, so that you can hand data traffic over to cells with different master clocks and not loose too many packets in the handshake.
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Not really, still a lot of surface area, and a small number of rocks, so plenty of much higher risk factors are going to overshadow them.
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@wurfyy With bears normally gallbladder and the bile is used.
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@SuzuranMajere So likely then that code is still in active use as control on missile systems. Wonder what happened to the Minuteman guidance computer Jim Williams had as a hall decoration, likely the LVDC software is the direct ancestor of that system, and the hardware likely is just an updated copy as well, just with a faster computer core that enabled it to handle the analogue computer functions in house.
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Linear accelerator will be lighter, and much less material to use to build, plus no high delta V means it does not need much power. Probably a hundredth the mass needed, though velocity will be lower, but a lot more accurate in aiming, so reducing the amount of mass needed for attitude control of the payloads.
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It will disperse very fast, just from radiation pressure and the tenuous atmosphere drag, so within a week you will be hard pressed to detect even single particles even following the launch trajectory exactly. Wonder more where the bigger parts are going to come down, hopefully not over populated areas, because the launch direction has very little water till you get over the pole and into the Pacific, so any mid stage "rapid unscheduled disassembly" is going to drop large chunks of metal all over the Russian Steppes, though to be fair the old USSR has dropped kilotons there already, and not all of it has been aluminium and steel with a smattering of titanium alloy.
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Somebody was having a bad Monday after the weekend, and the supervisor was out with them as well for the party.
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Also got a nice stroke years ago of lightning hitting an oil storage tank. Did not go well for the tank, it burned for a few days.
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Hopefully with the step up to 6 from 5 they also remember to also check the safety destruct systems, so as to update the parameters to the new performance, so as to not have it decide that the new performance is actually a failure and self destruct.
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Guess version 2 should include into the mass calculations the addition of a small set of doppler radar sensors, and use them during the landing, probably doing a disable of the data from them below 50m, because of dust. The 3 radars will be giving a X drift, a Y drift and an altitude above terrain, along with closing rate. That will allow them to remove residual error from the IMU units, which likely led to the rolling over, as the tiny errors accumulated during the journey, and rounding errors led to the ground drift likely being excessive, and thus it landed with a significant drift, which caused it to tumble.
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@ParkerUAS Actually designed for a much older aircraft, Aeromacchi Impala, which used that much current in the starter generator. Also has a big warning in the start instructions about not doing more than 2 consecutive start attempts without ground power as well, because that generator could, when the engine was running, also provide a peak of 8kA to charge the battery, and you then ran a risk that your battery would overheat rather spectacularly. Batteries all were modified to add a thermal warning switch to them, with a prominent light in the cockpit attached.
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Easier to just shove engines on, and drop them and the pumps when empty. They only have to be carried for 3 minutes then, otherwise you still have to carry probably 2 tons of plumbing and valving to orbit. Soviets ISTR did make drop off tanks, but gave up and slapped on simpler cheaper solid cores instead, easier to design and control. Extra tanks add weight that you have to take to MECO. Easier to dump parts after empty, and only take 100kg of attachments and stiffener ring you already mostly need instead.
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Don't worry, by now most of it is no longer the same element, more lead than anything else.
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Larry Niven and Jerry Pournelle did the same, using a massive ramscoop rocket that was using the hydrogen atmosphere of one of the outer gas giants as power source, coolant and reaction mass, with it pulsing and venting a plume to move the gas giant into a suitable orbit so as to draw out the earth moon couple to a wider orbit, along with doing other things like move Mars closer in, and also cleaning up the outer planets somewhat by tossing the one out to make the orbital mechanics easier. Big self repairing machinery that was designed to last essentially forever, and also to communicate with authorised personell.
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@TheExplosiveGuy Synthetic sapphire is glass clear, as it is pure monocrystalline aluminium oxide, which is what a sapphire and ruby is, just the red and other colours comes from impurities. The actual laser rods themselves are totally clear, though when they failed they usually turned to a fine powder from the energy release.
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SR71 you fly in a space suit, which will easily handle the temperature till you slow down, then keep you fed with oxygen till you get low enough that you can first have the larger drogue chute slow you down, then finally the seat parts company, leaving you in the suit alone, with a big parachute (your seat cushion in almost all cases) and a survival pack to land with.
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Nice thing about them is, even in a very light polluted cityscape, they are very visible as well, just after sunset (or just before sunrise) if you are looking up to the sky.
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Helicopters tend to avoid negative G for noise abatement purposes. Heck of a noise as the rotors hit the tail if you pull negative G past a point. Some helicopter designs include in the tail a heavy steel cutter bar, designed so that you get a very audible warning, as it chews the tips off the main rotor blades, that what you are doing is not a good idea. Yes you will need all new rotor blades, very expensive, and a good pit of panel work to fix the hole cut in the tail rotor, but still cheaper than losing the airframe. Do remember having a flight with some really stressed out pilots, who had spent 3 hours turning in circles to calibrate the magnetic compasses after a replacement, and I took the flight back instead of driving on the tractor. Sitting in the cabin, door open, legs out and holding to the strap, with the sky below my feet, and the ocean visible through the rotor blades, as they were doing barrel rolls in this 16 ton helicopter. Yes it could lift cargo, 16 tons max at sea level, and if you could fit it inside, it would carry it.
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@scottmanley OK thanks then, I was thinking it was Kodak film.
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Bond to the ring is a big failure point, you need to have rough surfaces to have a good bond, not a smooth surface. Needed that ring to have a rough surface to give it a large surface area to bond the metal to the composite. Then probably chemically etched to give a clean metal layer for bonding, right before the final solvent cleaning, and then application of the epoxy bonding it to the ring. Plus inner lip should have been a lot thicker, probably at least a quarter the thickness, with a transition to the inner diameter to keep the step stress down.
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Probably supplied by the same company, just had a little more care taken in processing to keep thickness variation, always there with thin foils, to a minimum, and to have a single pass pressing, so both sides are shiny, unlike the regular foil in which 2 foils are done at a time, with a thin oil coat between to prevent sticking, so as to cut time and cost. the foil from the roller is rolled onto a wide long roll, then goes to a slitter, where it gets cut to a width, then the length of foil required per pack is rolled onto the disposable mandrel in the box.
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@logicalfundy Should rename it New Horizons/Voyager 3, and leave a message in the spacecraft memory banks about that. Cold flash memory should last centuries without degradation.
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It will sink, it was designed to float down in a 93 bar Venusian atmosphere, where water will float 30km up, just before it boils away. But will probably survive hitting the ocean though, seeing as 70% of the impact path is over water.
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Outer layer would be destroyed by the sun, but the aluminium under will be mostly fine, except where the plastic of the threads has been destroyed, so the blankets will have sagged and deformed, with likely some of the structure visible now. Paint exposed will be basically only the oxide pigments, and the mineral powders and fillers, nothing organic left, except where sheltered. Glass exposed could likely be a lovely blue from photon and electron bombardment, though most of it would be brown for the same reason. Thin film of dust on everything, as it rains down from the sky, as a result of micrometeorite bombardment nearby causing dust to fly up, and also from static charge causing particles to levitate in the vacuum from charge generation due to impact from solar wind protons and electrons.
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Yes, return means you have to dissipate the exact same amount of energy as what was used to get you up there in the first place, and with no way to store it, it has to go as heat.
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Yes but they all have common adaptors for interconnect, so you can remove parts as separate pieces for the final orbits, and each section can go down with it's own Progress or Dragon providing thrust and some control.
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@keepernod2888 They might not all have a docking adaptor, but for sure they do all have a way to connect them in space, that also allows them to come apart. Both will have the plans, if not spare flight ready hardware, that they can use to cobble up a way to attach them to a booster stage.
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Falcon Heavy launching another Falcon 9 up, partly fuelled, with a second launch with another tank to fill it up. Your first one just needs a single vacuum Merlin engine on it, and then you will be able to get to a graveyard orbit up past GEO easily, or even put it into a lunar orbit. Going to be stressful on the station though, as the walls are not exactly thick, so only a low thrust long duration burn will do, thus only the one engine on the otherwise massive rocket, with most of the thrust going into making the fuel move.
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Coolant changed to something less flammable, to the great delight of the ground crews, who could now use neat in the after work drinking, and also because they now had free de icing fluid for the cars.
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Yes, just that crumple zone also has tiny complications, in that it is not empty space, but a lot of liquid that will combine, with a lot of gusto.
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The fate of 10 is still to be broken. When that occurs is still a question though, it might be one flight, or it might be a dozen, but it will be driven till it fails to get data.
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According to the song it always rains in Sunny California.
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@-danR High pressure gas comes into the check valve, then there is a orifice plate to provide some flow restraint, and then the burst disk. In the space between the 2 units you can add a simple leak detector. For the oxidiser just use a high pressure electric feed through and a plain low carbon steel thin wire that will be corroded open if there is any leakage, and similar for the fuel, as it is also corrosive. Cheap, and can be integrated into the flange and orifice plate as well with ease, along with a pressure test port. You could also add in pressure transducers and a low pressure fill with gas, but pressure sensors that will survive that fuel and oxidiser are not cheap, nor are they low mass, as you need a diaphragm and transfer fluid to keep from melting the silicon strain gauges, which are ironically the cheapest part of the sensor.
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Just proves only mad dogs and Englishmen go out in the midday sun. They are waiting for afternoon so it is cooler, and lucky for them afternoon lasts for over a week. But it gets really cold at night though, hope they took a blanket and heater that will keep themselves warm till morning.
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Vodka powered.
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HF reacts with everything, but in a lot of cases the metal flouride is a stable layer passivating the surface. Thus you can store HF in nickel tanks, and use pure nickel plant to handle it, because NiF is at least similar in size to Ni metal, and bonds well. Just like Aluminium oxide is a passivation layer for insanely reactive Aluminium. Just do not have any sort of cavitation that will scour this layer away, and pour your liquid in slowly and carefully.
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@paulhaynes8045 The phone has GPS yes, but also the towers, because they have a fixed nearby location, also will send the ephemeris data for all the locally visible satellites to the phone on request, so the phone GPS can lock really fast, and it also uses the time difference between local towers to gat a very fast and somewhat accurate location if indoors, so that it can at least give a position to within 30m almost immediately, even if there is no sight of the sky for GPS signals. The GPS signal is used outside in your car, to track better, but rough location is done using the signal strength and timing of local towers. Did once turn on a phone GPS with no coverage from the network, and it took around 20 minutes to finally position me, within a 100m sphere, while another phone, with service and data, took under a minute to position, using data and the 2 visible towers to get a rough area to gain coarse position fast. GPS in your phone needs data, stand alone GPS can do without it, though your accuracy improves with time on, as it refines errors out long term, though you also get the map used providing some sort of sanity check, as there is an assumption if you are moving you are on a road, allowing it to remove parallel paths easily.
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@abarratt8869 Yes the phone does not use GPS time info, it just in most cases uses the time, date and UTC offset sent as part of the phone network operator control data stream to set time and date on the phone, along with the time zone, and that is then visible to apps and the user. The cell data control uses the time it gets from the GPS and reference cells to time stamp the packets of data sent to and from the phone, so as to allow message blocks to be sent out of sequence, if that helps with the instantaneous power and bandwidth management, and then each side will reconstitute the streams of data back into a single seemingly monotonic stream.
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Very carefully, probably by having a counterweight that changes position to compensate for the mass loss on the one side, likely using some form of stored energy in the arm to move it inward to a balancing position.
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Those tiles, just like MH370 parts, will start to wash up on beaches all over the Indian ocean soon enough, along with any light floating parts. Probably time to start making the beachcombers and cleaners on the tropical islands aware of the need to look out for floating stuff that is hard, so they can collect them instead of dumping them.
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Not necessarily that the parachute will fail to operate, it could, because of the Russian space program wanting simplicity and robustness, have a very simple pressure capsule that was only armed by a pin being pulled during separation, that now is waiting for the pressure to approach a part atmosphere, which would be the opening pressure in the upper Venusian atmosphere, and thus acting as a backup for the electronic trigger, or it also acts to power up the lander, as it would assume it was doing reentry, and thus connect the internal batteries to the electronics. 50 years and the batteries might have still some residual charge, enough to have it give a final few seconds of swansong, as the radio transmitter operates for a few moments before they deplete completely.
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Another thing about that old steam turbine is the ends of the shaft, where the thrust bearings are. Multiple bearing faces, with pressurised oil feeding them, because no ball bearing of the time could withstand the thrust and rotational speed, so they simply used lots of bearing surfaces, and put them in parallel, so the oil film could still provide protection.
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Problem is flight needs a great deal of power, as you basically are flying in what would have been classed 150 years ago as a pretty good vacuum.
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@OkieOtaku Well, I normally do this for things like chicken and rabbit when they are being done over a nice set of coals, though you can save a lot of time with judicious precooking in a pot with water and spices, to keep the meat moist and get heat all the way through, along with flavour, and finally just do the outside to get the nice flavour from the Maillard reactions.
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@jasoncdebussy Henny Penny pressure cooker will do that sucker in 15 minutes right through, though you will have a lot of oil in the meat. That is what KFC uses to do the chicken, and those take 12 minutes per cycle when you are running flat out.
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Remember every survivor of an ejection does get a tie pin from Martin Baker, as testament to surviving the event. Fun thing is the speed at which it does eject you does compress your spine, so you will only ever eject once, as the second time might kill you. Your legs get pulled in with straps, but your hands are not pulled in, instead you have both hands on either the top ejection pull ring, or the one between your legs. You do though want to pull your legs in before, as there is a rather good chance if you do forget that those straps that pull your legs in to the seat are there, and that they pull your feet in by being attached to the airframe, and pull in while the seat is busy making you 10cm shorter. You have a greater than 50% chance that unprepared your ankles and shins will be broken. Yes have chatted to pilots that survived landing separate to the plane, and met the one who landed missing large parts of the airframe behind his seat, but still had a working engine (sans afterburner, seeing as the missile hit that), and no parachute or brakes. Him ejecting would have been fatal, he is a little past the design envelope for that particular seat design, and ejecting would mean his head was the canopy breaker. Fighter pilots are in general short and stocky, because the cockpits are designed for short and stocky people. Very uncomfortable for bigger or taller people like me to fit in there.
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Would say they will not put those samples in nitrogen, entirely too reactive, most likely the samples will be stored half in a high purity vacuum, and then the half that is to be examined will come up to atmospheric pressure in an argon atmosphere, as that at least can easily be gotten as an isotopically pure gas, and is a common enough trace gas in atmosphere, but not reactive easily, unless you have elemental fluorine in the sample.
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@stevevernon1978 Probably no time, or they did not think to include this ability in the uplink channel command set, so they could command the first stage to do an early MECO and force separation that way.
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As more satellites were added in different orbits, accuracy improved. With low numbers of satellites, and also with long paths through the air to provide diffraction of the signal, you got poor accuracy. More orbits meant more visible at any time, and thus a more precise position. You need, IIRC, at least 4 to get a coarse position in 3 axes, and with every added satellite visible at the same time your error reduces. At 6 you get 100m, and with more the error reduces further, with most receivers able to handle up to 12 simultaneous decodes at a time, and with more sophisticated receivers using ADC units that can sample at the actual chirp bit rate, timing each individual bit as it comes in, and thus being able to correct for smaller drift with each cycle. Some of the software defined units have no real limit on the number of satellites they can view simultaneously, just depends on the amount of memory and processor speed, as you can always add more of both, and make the rake receiver scale with visible satellite numbers. Some of those have impressive cold start capability, being able to start from cold within a few minutes, and with warm start capability of seconds, provided the data they have is not too stale. Big issue is with noise, you find that often GPS signals in urban areas are poor, lots of RF noise desensitising the receiver, and also urban canyons making for lots of multipath distortion, and limiting visible sky to use. Sometimes I need to restart the old Garmin I have a few times, as it is unable to start, but often during RF quiet times it will be up and running in 2 minutes, from a warm start.
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@DrDeuteron They use Plutonium 238, which is relatively safe, and yes the decay products are mostly alpha and beta emitters, at least the early products, though somewhere there are neutrinos produced, but not much. Mostly heat, so good for energy, but yes by the time you get to further down your battery is long gone.
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@iancooper8777 Yes they dump most of the electron energy by using a high bandgap semiconductor to capture those electrons. Think large area Silicon carbide LED's used as electron capture devices, dumping the rest as heat. You stack the thin film detectors on either side of the source, to capture the most energy, and pump the assembly down to a pretty good vacuum as well.
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@ericlotze7724 Not much about VFD's other than they all die eventually. The SOS construction because you have to grow a film on an insulator for electrodes, and sapphire in pure form is transparent, and making the whole clock in the display area is possible, as the electronics can all be coated with silicon nitride to provide isolation afterwards, except for some bumps at the edge of the device that are built up with aluminium to make the top layer connections. You probably will want to use an electrochromic display instead of LCD though, as that saves a lot of power, though you will still need to have a capacitor to store the energy needed to refresh the display, which likely will only update once a minute. But same construction physically as LCD, just needs a very low current high voltage (around12V) power source to do the update. Going to be fun to do the crystal drive though, with nanowatts of power available, and typical watch crystals being in the microwatt range for drive. Battery array likely to be a lot bigger and thicker than the display. your wristwatch is going to be Rolex Oyster size, and only rated to 10m depth.
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@casualbird7671 They are running on the failed receiver, that has lost the ability to track frequency and doppler shift, and are running on the backup thrusters, originally used for orbital insertion when launched. But still working after decades of use. I would say that the big Dish just ramped power up to full power, meaning they shortened the life of the Klystron tubes a bit by eroding the filaments and anodes, but not by too much. They do have at least a full set of hot spares there, and another set or two of tubes in storage to replace them, and then send out the tubes to be rebuilt. There are a few companies that still rebuild both CRT tubes and large transmitter tubes, because there are some applications where replacing them is either very expensive, or very difficult.
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@heuhen They also had a launch where the astronaut commented he had hoped to be a little higher at MECO.
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Well, not being American, and also not liking turkey, can we replace the bird with something else. For me that would be Ostrich, which is a much larger bird, but which does taste a lot better than turkey, and which is quite common these days world wide as an exotic fat free meat.
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Falling into a singularity you would, provided it is big enough that you are not turned to particle soup before actually reaching the event horizon, not notice anything, though you will at some point be able to see the CMB as visible light, telling you that you likely are about to pass the event horizon. Of course this also says that you will long have lost the ability to communicate this information to an outside observer, as they likely will be millennia dead, at that point outside of the steep gravity well.
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That is woven polyamide, same as the plastic, with a polyamide thread used to sew them together, in a loose stitch so the packing could keep the layers apart.
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No, just too heavy.
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Peroxide not too common because of contamination issues. LOX if you get a tiny bit of steel fluff not too much of a problem, instant rusted away. Peroxide you get catalysed reaction, that makes nice hot steam and hot oxygen, which then causes reactions with other parts, and lots of extra pressure in there. Small volumes and exotic materials are cheap enough, but when you have to make entire tanks out of exotic stainless steel alloys, and not use any sort of grinding or machining operation, that might have small ferrous particles in it, it gets real expensive real fast.
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@johnladuke6475 Probably there, but they instead fitted TEMU airbag emulators instead, because those are cheap.
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Apollo was the same, and before that Mercury also had troubles.
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Possibly a lubricant leak into the methane causing the colour change, from contaminated methane, burning slower hydrocarbon chains. That would account for the flame as well, venting from an overpressure relief on the hydraulic system, and the faster landing was to get down as fast as possible, before the hydraulic systems totally failed.
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@michaireneuszjakubowski5289 Thing is that as a single aircraft it had a very limited lifetime, your airframe needs periodic inspection, and this is actually more expensive than building the aircraft new again. Hopefully they will build at least 2 new ones, as the cargo capability will be used for sure, and having two or more makes the cost so much lower to maintain, as your costs to manufacture is not linear with number, and building 2 or more, with the knowledge from the years of running the first one, will not be as expensive, as the new ones will have all the fixes that went into the first one, and thus will be much improved. Yes it needs to be rebuilt, another casualty of this senseless posturing.
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True, but to get bulk cargo up it will work, simply because electric power is cheaper than fossil fuel, especially if you can have peak power use from renewable resources, and the motor set used to launch can make a pretty effective energy store as well, for recovering energy.
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