F-22 с российскими катапультами!

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Russian Egress System (K-36)

kmceject
Veteran
Joined: Oct 01, 2003
Location: New York area
Posted: Aug 20, 2004 - 12:27 AM


O.k., let me make one thing clear. I am not denegrating the K-36 system. What I am saying is the K-36 may or may not be the 'best seat in the world'. To be perfectly honest there is no way to completely be sure of what the best seat is. The K-36 according to Zvezda has never had a failure (although they later have admitted a failure of the boom during the 1989 Paris Air Show mishap, after being confronted by the photos.) The NACES system used in the F-14D, F/A-18 (later) and T-45 has a 100% success rate. The ACES II has a 95% or better rating depending on the version.

The ACES II is typically better on a low altitude ejection in all probablity. I am not sure a K-36 would have saved CAPT Stricklin of the Thunderbirds should he have ejected at the same millisecond. Certainly the version used in 1989 would not have saved him as it had a mechanical 3.5 second delay before parachute deployment. The 1999 films show that has been changed, but I don't know the details on the same system.

Ejection from a fireball... well, how about this one- a Canberra was on final approach when the nav and bombadier realized the aircraft was about to stall out. They pulled the face curtains simultaneously as the aircraft rolled and the wing contacted the ground and the aircraft was cartwheeling. Tossed out at a 90 degree angle, one of them hit the ground in his seat with only the drogue out. The other was killed because his drogue slug entangled with the frangible hatch. The survivor's parachute was still packed. He had several injuries, but healed well. That was in 1966 using a Martin-Baker Mk. 2/3 seat. Martin-Baker now is up to the Mk. 16 family in production, and many plans for even more improved seats (Mk. 16 family- 100% survival so far too.)

Another fireball ejection- a Harrier pilot was flying at an airshow when he was notified his aircraft was on fire. He landed from a hover and ejected from the flaming aircraft with no injuries (although the seat killed a spectator.)

Just using the films of airshow ejections, you may not be able to gage how good a seat is. The famous 1989 lawn dart photos got the USAF quite interested in the K-36 system. They spoke with McDonnell-Douglas about 'why aren't our seats as good as the Russians!'. MCD did a computer analysis that showed that using the Minipac (a low capability seat designed for trainers and possibly rotary wing use) would have had the pilot under a full parachute about 100ft in the air based on the same exact initiation time. The films of the 89 ejection show the parachute reached full bloom exactly as the pilot's feet hit the ground. The ACES II was already a mature technology at that time and was much faster than the Minipac so MCD felt it was unnecessary to compare it if the Minipac was so capable. Even so the USAF over the years periodically revisted the K-36 because of that and other airshow ejections.

The USAF, USN and other agencies executed a Foreign Comparative Testing Program (FCT) with Zvezda in the early 90s. They tested the K-36 in both the US and in Russia. The report often is available on Ebay on CD-Rom, but you can download it for free from the USAF if you know where to look. They found that the K-36 was indeed much more stable than the ACES II in many ejections at high speed, however there were issues with the restraint systems. I have the films of several of the tests. The one thing that was singled out as an issue was the 3.5 second mechanical delay. In one test this led to a horizontal travel of the K-36 for almost a quarter mile longer than an ACES II would have given under the same conditions. Due to the test situation- a horizontal sled run- it did not matter for safe recovery, however sould there have been a downward componant to the inertia, such as CAPT Stricklin's ejection, that quarter mile would have been a significant issue.

Obviously Zvezda took the concerns seriously as the 1999 films show. I have also heard I.G. Severin (head of Zvezda) make statements about the improved systems that are quite interesting. They are still quite secretive about their statistics however so most of what I hear I label as marketing, not data.

As to the stability issues, the K-36 is stable because of the use of a pair of telescoping booms. They extend back from the shoulder area and are spread at about a 15 degree angle. (One of these booms failed to deploy in 1989. They said it was the one and only time one failed... Should this have happened at high speed the results would have likely been less good for the occupant.) These booms are based on technology developed in the 1950s in the United States and were fitted to the Convair Rotational seat, aka the 'B' seat, and the Bobsled seat. They were also used on the X-15 seat. Matter of fact, the X-15 and B seats seem to have been the inspiration for several features on the K-36.

In the US there has been much investigation on the ACES II system to improve the stability. They have tested what should really be the future of egress systems- a steerable propulsion system. This was tested on the 4th Generation Ejection Seat, part of the CREST program. The 4th Gen seat was very effective, even up to 700KEAS, however it was cancelled due to costs. Booms are being investigated for retrofitting to ACES II seats too. The British are also experimenting with booms for the NACES and other seats. The Mk. 16 family includes seats with deploying panels that do similar functions.

Of course so far no NACES or later seats have been 'demonstrated' on film at airshows or other places. The ACES II only has a few 'public' demonstrations such as CAPT Stricklin's, and the F-117 at the Baltimore show. Of these, only Stricklin's was of a very dangerous part of the envelope. His ejection was at an extreme sink rate, to the degree that his aircraft was trenching the ground less than 2 tenths of a second after he cleared the cockpit. That is a very short period of time. That, in my opinion, makes his ejection the most spectacular 'live' ejection ever caught on tape.

As to the K-36, I'll leave you with this comparison I mentioned before. Dig out your links to the 1999 Paris Airshow Su-30MKI mishap and watch it. Once you have finished with the wow factor, check out this film.

That is the footage of a F-4 Phantom II with a stuck stabilator on takeoff. With the exception of the inter-seat sequence delay (probably a dual, manually-initiated, non-sequenced ejection) on the F_4 ejection, the films are remarkably similar. Considering this footage is about 30 years older than the other, tell me what it tells you about which is a better seat?

[edited to add-]
Conclusion- I am a firm believer in studying all available information before making up my mind. I highly recommend that you take what I say with a grain of salt, make up your own mind. I am a historian of egress systems and have studied these things for over 25 years. I try my best to be fair and balanced (more so than F*x). I just want people to understand the difference between reporting and facts. The K-36 has had some very good press thanks to the 'spectacular' saves and videos of such saves. The ACES II, NACES, Mk. 16, etc. have not had the same benefit. Is that a bad thing? I think not. Although I am a great fan of ejection seats, I'd rather see them end their careers in the boneyard with a complete airframe and no loss of life or equipment over the years. Should they be needed I'd like them to work 100% and save the lives they are entrusted. There are very few seats in the world right now I'd fear riding, and those are designs that are 40+ years old. Should I know that I would have to eject on a particular flight I have my preferences to what seat I'd ride. If you read my post above I probably let you know what I think, although I tried not to be that obvious...

Kevin
The Ejection Site
ps check that Pop-Sci article- I provided the pix of the K-36 to them...