Comments by "Tara Raboomdiay" (@tararaboomdiay7442) on "Defense News"
channel.
-
2
-
2
-
@DeathlordSlavik Sorry,it was a semantics thing, I was trying to differentiate between Sikorsky's more advanced concept and regular coaxials , so technically I was wrong and should have said X2 was a very advanced subset of the overall concept of coaxials/stacked rotors. Look at Kamov's masts, distance between rotors, shape of blades, hub thickness of mast, etc. Those are not intended for high speeds. Kamov was designing craft that were compact and avoided tail rotor issues. Even the KA-50/52 stays well under 200 knots They've been doing coaxial designs since the early '50s. It's their signature concept, just like tandem rotor technology was Piasecki's. you can see the ultimate expression of Piasecki's concept in the CH-46 and-47, which were designed by Piasecki and were acquired when Boeing bought the corporation (which was called Vertol) in 1960.
The S-69 was a research aircraft designed to test and demonstrate Sikorsky's Advancing Blade Concept, which was not a conventional coaxial and was the precursor the the X2 technology. This also was the time of the XV-15 Tilt-Rotor demonstrator. Without going into too much detail, it was half the speed of the XV-15. They eventually hung two turbojets on it, which raised the weight to the point it could no longer HOGE, but even with those blasting away and the aircraft in a shallow dive, its top speed was still 69 knots slower than the XV-15.
Sikorsky is already where? Just look at how many of their self set schedules and goals they missed on both S-97 and SB>1. They are higher risk
2
-
2
-
2
-
2
-
2
-
Assuming the rotors work the same as in the V-22, and videos indicate they do, there is a large "twist" to the blades and they will be operating at a high pitch angle. Unlike a regular prop plane, the roots will be nearly edge on and the tips will have a quite significant angle relative to the direction of flight. In other words it won't appear to a radar as a flat spinning disc, but more of a "faceted" type of surface, sort of like what was done on the F-117. I'm not saying it will be a stealth aircraft, like the F-117, just that the return isn't going to be the big thing people worry about at first glance. Bell has demonstrated nose down backwards flight, possibly not as much as Defiant is theoretically capable of (although Defaint will have the limit of how far "back" you can tilt the disc, whereas Valor does not have to worry about the blades coming too close to the fuselage). Frankly, enemies are going to be shooting at the fuselage because it's an easier target, so the question applies to both craft:. how vulnerable are the engines/transmission,/blades, etc.
2
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
Why can't you fight fires or do disaster response? It meets the Army's requirement for sling load, and should be able to do it as well as Black Hawk (as an aside, V-22 holds world speed record for carrying external load). If you look at Army bases, most helos aren't stored in hangars all the time. V-280 is wider than Defiant (H-60, BTW, is wider than the H-1 it replaced), but so what? It's shorter. More importantly, even acknowledging the greater width, nothing is better than everyone at everything. The choice is, weighing up the pluses and minuses, what gives you the most overall?
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
@Michael02703 Here's the thing. In one of my other posts I covered this in detail, so I'll be brief. V-22 can autorotate, but like other large helicopters it does it badly. This is due to a restriction imposed on the size of the rotors and the fact that the gov't supplied an engine that was heavier and burned more fuel than what they told Bell-Boeing to design for, which makes the craft heavier than planned. This is also what causes the downwash, because of the higher disc loading. Both V-22 and V-280 are Tilt-Rotors, but projecting one on the other just because they both use Tilt-Rotor technology would be the same as saying back in the day we shouldn't develop the F-16 because it is a single engined jet like the F-8 and the F-8 had an appalling safety record (it did, even ignoring combat losses). The XV-15 and AW609 have both demonstrated much better autorotation. AFAIK V-280 hasn't because it wasn't required for JMR-TD and it's the only one Bell had and you don't want to do anything too far out if you've only got one. If all you want to do is go normal helicopter speeds for normal helicopter ranges with normal ,helicopter performance, a Tilt-Rotor will lose every time. There are always tradeoffs. A Tilt-Rotor can do a helicopter's job, but not as efficiently, but a helicopter can't do a Tilt-Rotor's job. The question is, what do you need?
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1
-
1