Comments by "Mikko Rantalainen" (@MikkoRantalainen) on "Mentour Now!" channel.

  1.  @samik83  I find it pretty hard to believe that FAA would have accepted their request no matter how many requests they would have made as long as the following exception was part of the request: flying a plane without safety pilot inside the plane in the public airspace. This stunt team got their execution order wrong and they should be punished for willingly breaking the rules after getting written decision not to do so. They would have just needed to follow rule "don't promise any specific implementation of the stunt that you're going to need an official permission for, and such permission has been never been granted to anybody". Start to advertise your specific implementation when you get the permission. For me, the stunt would have been exactly the same even if there had been safety pilots in both planes as long as you had uncut video for those safety pilots demonstrating that they do not control the airplane. It would have also made good content to show this failed attempt and the need for safety pilot to take control. And then do a successful stunt on second attempt. You shouldn't pretend that hard stuff is easy.
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  2.  @awdrifter3394  I think the situation with MCAS was different in that the marketing and management had already decided that additional pilot training is not an option even before the engineering had figured out if that's actually possible. And the angle of attack (AoA) sensor couldn't be made mandatory part because that would have made that critical part of the aircraft, which will always require mandatory training. So that option was off the table because of political decision that marketing or management had already made without understanding the consequences. This time it appears more probable that the problem was error in manufacturing and that was not caught because of incorrectly designed or implemented QA process. It doesn't seem that there was any reason for politics to prevent doing that part correctly, unlike with MCAS.
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  3. Some people have also claimed that all the maintenance documentation is nowadays in the cloud and the sanctions even prevent the Russian engineers to read the documentation for the maintenance procedures. Do you have any information if this is indeed true?
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  4.  @jefferysterner  This is Red Bull marketing department, cost is literally a no-issue.
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  5. Ryan Air (RYA/7S) is a small Alaskan bush freight company. Ryanair (RYR/FR) is the European low-cost carrier. Which one did you actually mean?
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  6.  @kanytonaan5594  Are you asking if that question was a joke? 99%
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  7.  @kanytonaan5594  Yeah, it was joke about how mispelling Ryanair as "Ryan Air" results in a real airline name which is not the same thing.
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  8.  @kanytonaan5594  It was 99% joke and 1% of truth.
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  9.  @bordershader  I think the missing videos are just a YouTube thing. I get that in most videos and sometimes pressing the little (i) icon in top right corner can be used to workaround the issue.
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  10. Looks like ditching a burner phone! It seems to be shattering while hitting the ground. ... or ice from the window border.
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  11.  @JelMain  It would have been illegal but they could have gotten FAA permission for that. Instead of doing anything that FAA would have considered safe, they decided to execute the stunt without adequate safety. I think revoking their licenses would be a suitable decision. That obviously wouldn't prevent them from flying planes anyway, as they've already demonstrated but at least they could no longer pretend to be following the rules.
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  12. I would assume that for the next 10–20 years, the most economically viable solution is to switch to fully synthetic jet fuel. That would result in zero CO2 emissions without range problems and the jets could fall back to regular jet fuel in case synthetic fuel production fails for any reason. The only problem is cost, once again. Synthetic jet fuel (produced from electricity, water and CO2 captured from the atmosphere) is pretty expensive to made and airlines have close zero interest to switch to it unless forced.
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  13. I think it was stupid to crash that airplane for no good reason. However, I would be totally happy with Red Bull taking risks and potentially destroying the airplane, just like race cars are potentially (and in practice, too) destroyed on track when something goes wrong. (Just check how much damage than Red Bull F1 teams has taken along the years.) However, when you want to execute stunts in public airspace you have to follow the rules of public airspace. Red Bull could have taken this stunt to private airspace or they could have used safety pilots. Instead, they decided to go against direct decision of FAA and execute the stunt in public airspace without safety pilots.
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  14. I think one hard problem that still needs to be solved is controlling the hydrogen in case of accidents. The jet fuel has been designed to be extremely non-flammable as a liquid but you cannot do similar modifications to hydrogen.
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  15.  @JohnnyWednesday  Why do you believe that "the sensors are more sensitive the closer the pressure is to ambient"? I would assume they are using solid state absolute pressure sensors (similar to automotive) and those have nothing in the design that would make them more accurate close to 1000 mbar absolute pressure. The sensor should output about 250 mbar absolute when the aircraft is flying at 33000 ft.
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  16. I just hope that the cockpit voice recorder was correctly used and the recording was archived.
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  17. 11:15 I think it's more probable that Russia will re-enter the market after the war is over but because of the facts that Petter said in this video, they cannot compete with similar prices to other vendors. As a result, they will have to sell the same items for cheaper than the competition. If their whole economy is bad enough, they will still have the workers to do it but their economy will stay bad for a really long time if that actually happens. The know-how and the factories in Russia are not (currently?) vulnerable to the war so the production quality should still be there immediately after the war ends.
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  18. Is aviation still using GPS only? Differential satellite system that uses all of GPS, GLONASS, BDS and GALILEO would be really hard to spoof. Of course, if you simply jam all those frequencies, you can do denial-of-service (DOS) attack but that's much more easier to cope than incorrect data to positioning systems.
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  19. Interesting discussion! I totally agree that ChatGPT or GPT-4 are not able to become AGI without major overhaul of the underlying architecture. However, future AGI could use GPT-4-like AI subsystems as part of its input. The major missing parts of GPT-4 are ability to learn anything over time (GPT-4 has learning phase totally separate from any input it has via its API or with the UI) and ability to estimate the accuracy of incoming data and the accuracy of its own output. That said, even GPT-4-like AI could be training in an aircraft simulator to accurately detect failures in the system, even when multiple systems fail at once. That would require giving all constantly known input data (all sensor readings, controller inputs, accelerometer data) and then training it to output estimate whether or not the aircraft will behave normally in near term future and if not, what's the cause for the non-normal operation. Such AI would be really valuable if it could emit message like "Engine 3 is using more fuel than expected but all temperatures are within spec. Possible fuel leak or fuel cauge sensor failure." In a sim environment, the AI could be trained for every failed system the simulator system can simulate. And then trained with multple failures happening at the same time. AI should be much better than humans in noticing the patterns in different sensors and controls.
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  20.  @vbscript2  The sidesticks also allow faster user input compared to yoke because the movement only needs to be done with the wrist instead of the whole hand. This alone is big enough reason to use sidesticks for fighters but I'm not sure if this difference is never important for passanger planes.
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  21.  @arturoeugster7228  Thanks for the information. Can you tell how much latency from the stick movement to flight surfaces actually moving to full range of input there is? I think the pilot induced oscillation is always caused by total system latency (pilot reaction time plus system physical movement time combined). I would have expected that the force feedback from the stick would allow the pilot to workaround the latency needed for moving the actual flight surfaces. However, I believe that that's not true if you've done actual testing with it.
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  22.  @arturoeugster7228  F-22 and other intentionally aerodynamically unstable things do indeed require lots of computer assistance to be flyable at all. And as such, human-computer-physical system interaction can easily result in PIO.
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  23. As a non-pilot software developer, wouldn't it be possible to have autopilot automatically execute emergency descend to 10000 ft if pressurization is lost during autopilot operation, especially for all single pilot planes? If pilot is not incapacitated, he or she would obviously take control if such action is not wanted so that part should be safe. How much risk would such automated emergency descend cause for the other planes nearby compared to pilot initiated manual emergency descend?
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  24. Also remember that if you travel to somewhere and intend to bring your devices back during the return flight, you have to limit the amount of devices according to the requirements of the more limiting flight. If the flight are operated by different companies, the limits might be wildly different. You can only safely expect to be allowed to carry one phone and one laptop and even the laptop battery is limited to 99 Wh max capacity.
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  25. And it's also worth remembering that batteries are only going to get better in the future. Many companies are trying to manufacture solid state batteries which might solve all the fire hazard risks in cells currently in use. Nobody has been figured out economically viable way to manufacture competitive solid state batteries yet but there are multiple research projects going in parallel and it seems to be just matter of time until at least one solution can be found.
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  26. The door is pretty flat object and would probably glide in the air. The initial orientation in the air probably defines which way it will glide.
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  27. I think that unless Boeing changes lots of the management people, training considerations will be more important than any technical pros and cons. Just consider the fact why MAX had two major accidents: it was because Boeing pushed training requirements above anything else. As a result, yoke it is.
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  28. I think they should have been granted permission for this stunt but not in public airspace as they requested. If you want to do stunt like this in public airspace, you should have the safety pilots in every plane for reasons that should be obvious after watching this video.
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  29. Great video! I have only two questions: Is it normal that the nose wheel has this many different issues? Does Airbus A320 have more complex nose wheel design than nose wheels of other aircraft usually have?
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  30. I think it's the same reason why they "couldn't" use safety pilots like they did during the training sessions. Pure marketing department decision. When it comes to marketing department vs aviation safety and disobeying FAA decision, the marketing department should automatically lose. Red Bull team thought otherwise and these soon to be ex-pilots took the risk.
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  31. I was thinking the same thing. Until this, I haven't seen Red Bull stunt that goes against the official regulation. I wouldn't been surprised to find that these two soon to be ex-pilots decided to do the stunt without FAA approval without the Red Bull legal team having any idea about the situation.
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  32. If Brilliant had been sponsor of this episode, that would have been perfect spot for the ad.
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  33. I would really love that a passager would be given a weight budget (e.g. 100 kg) for the trip. If you weight 80 kg, you can carry 20 kg of luggage for free. If you weight 60 kg, you can carray 40 kg for free. And if you weight 100 kg, no get no luggage for free. That would be totally fair for everybody and it would be better for the companies, too, because they would know the exact weight of the airplane.
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  34. I think using fully synthetic fuel made out of water, CO2 captured from the atmosphere and electricity is the way to go until we have good enough battery technology to convert airplanes to pure electric. Even with CO2 capture, you could have zero CO2 emissions but NOx emissions are still a problem so that shouldn't be considered permanent solution.
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  35. It will be interesting to see if future long distance travel will be done with supersonic jets or SpaceX Spaceship. The problem with SpaceX design is that the noise from the lift-off makes Concorde appear nearly silent airplane. SpaceX design could allow flying from New York to Tokyo in about an hour, though.
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  36.  @MarkRose1337  If you write the full title and author name of the study that you consider the most trustworthy, it will be easy to find and will not be blocked by YouTube.
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  37. I think this video well underlines how even small details do matter. I automatically only considered that "of course the captain could fly the aircraft from the right seat" but I failed to consider the FO not having any training for the left seat.
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  38.  @ddpeak1  Exactly. 250 MHz safety buffer is like 40 TV channels worth of bandwidth. TV sets were accurate enough over 50 years ago to separate 6 MHz channels. 250 MHz should be plenty safety margin for a radio receiver.
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  39.  @joerivanlier1180  The only reason this crash happened was because they didn't have safety pilot in the cockpit like they did have during the training. And the FAA decided that removing the safety pilot is not okay. So these soon to be ex-pilots decided to remove the safety pilot anyway and crashed the plane as a result. Had they done the stunt otherwise identically but have the safety pilot inside the plane as required by the FAA, we woudn't be having this discussion. And that's because when you execute stunts like this well, you have a plan for "what if something goes wrong" for real. It seems that they had some kind of half-assed parachute for the plane that obviously didn't work either.
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  40.  @Ldavies2  Or simply raise the licensing fees to make the plane manufacturers to pay for their planes?
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  41. You could also continously send cockpit voice recorder audio compressed with speex which should be able to transmit understandable human voice using just 700 bps or 88 bytes per second. Multiply that by 4 audio channels and cockipit audio recorder audio would take 1.3 MB per hour for 4 channels! And you could transmit just one sample per second for each 88 data channels which would result in about 1.3 MB per hour (assuming 4 byte sample per channel which is enough for 32 bit integer or 32 bit floating point number), too. So instead of transmitting 20 GB/h you could transmit less than 3 MB/h and still have 4 channels of audio recording and 88 data channels with one sample per second. That's obviously not as good as the real black box data but transmitting 3 MB/h shouldn't be too hard and having heavily compressed audio and one sample per data channel should be plenty if alternative is no black box data at all in some rare cases. I'd assume that transmitting about 200 bytes per second wouldn't be too hard using the existing radio systems.
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  42. Another example where unions cause weird issues in the USA. I understand unions negotiating the salary but unions setting e.g. usable seat counts for a aircraft is definitely going too far.
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  43.  @leanderzulu3494  Is the current situation actually an improvement?
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  44. If they run TT Races on the Isle of Man on public roads after getting denial for the request to close the roads or otherwise make it safe for public (or close the airspace for this specific stunt), would you think it would be fine that they continued without the permission anyway?
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  45. 5:30 The current USA system also results in flight instructors being less experienced because highly experienced instructors would switch to better paid jobs. I think it would be better for the aviation industry if the instructors from the start were highly skilled. In long run this results in self-spiraling loop where every next generation of flight instructors has less and less experienced teachers!
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  46. 2:38 I've been writing software for living for a couple of decades and I can tell you that there's nothing as permanent as a temporary solution that works.
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  47.  @jujuu1339  I would argue that no smartphone or screen protector is 9H for real. In marketing materials, sure, but if you actually test scratching it, nope.
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  48.  @Huntracony  When the plane goes uncontrolled, there's always a possibility that e.g. weld seam of such ad hoc speed brake simply fractures and changes the flight charasterics so much that unpiloted plane could go absolutely anywhere within the limitation of fuel onboard. It's pretty obvious that there's more than one way this kind of stunt might fail and the only reason they took away the safety pilots was marketing deparment's wishes.
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  49. Exactly! Having the safety pilots in those planes would not have been any less awesome than using crash helmet or body armor in some other stunts.
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  50.  @holker_  I totally agree that you have to set the bar based on skill, not on experience. And measuring skill is hard but not impossible.
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