rickshaw said:
LowObservable said:
It's a long-running debate.
Yep, sure is. Personally I believe the internecine rivalry between the services in the US military is pretty insane and wastes far more money than it saves.
In the case of the US Navy, the list of non-negotiable requirements is so pervasive that you do, indeed, end up with a new airplane if you want to adapt a land-based jet for carrier use. It's approach speed, over-the-nose visibility, cat and arrest loads, impact loads, even main landing gear location for tip-over issues.
They aren't constraints, they are merely a wish-list for optimisation. If the US Navy was more willing to accept compromises, it would end up with more money to spend on either more aircraft or perhaps (shock! Horror!) ships.
I suspect the Soviet central planners told the Navy, "no you cannot haz new jetz" or the equivalent and that they were simply forced to eat any penalties (like folding horizontal stabs on the Su-33. Eeeks).
I rather suspect they have suffered few penalties. Have you seen the video of the Su-27 which crashlanded at the East European airshow when the pilot forgot to put his landing gear down? It slid gently to a stop on the runway, they jacked it up and replaced the missile rails and it was ready to fly again. I cannot imagine that happening with say an American fighter without major structural damage occurring. It appears to me that the Sukhoi family in particular is built, as we like to say downunder like a "brick dunny".
The best approach so far is the Rafale, where the two versions were designed in parallel, using what was then very good CAD software - I suspect that the challenge is what made CATIA so dominant - so that the extra weight was concentrated in a small number of components.
CAD eases design, without a doubt, allowing rapid changes between structural parts. If they'd had it in the late 1950s/early 1960s, then the F-111A/B design process would have been a lot easier IMO.
There are certain requirements you simply have to meet in order to have a non-V/STOL carrier based plane. The most obvious, of course, is that you have to be strong enough. It's not just having a nose gear that won't get torn off and thrown down the catapult when it fires. It's equally bad if the whole tail of the aircraft is ripped off when you make repeated arrested landings. While a number of land-based fighters now have arresting hooks, they are there for emergency, not repeated, use, they are not intended to be used on every landing and the deceleration is less than that on a carrier landing. You also need an entire keel structure that can take the stress of repeated cat launches and arrested landings, including the higher vertical impact speed at touchdown. In addition, the whole aircraft, including electronics, has to be strong enough to take the shock of catapult launches and "controlled crash" landings. These are not wish-list items, they are absolutes. If you don't have these, you don't get to operate from a carrier.
In addition, the final approach has to be flown at a fixed angle of attack, essentially flared all the way to touchdown. This requires more tail control authority in both planes. This is the bugaboo that affected both JSF designs and required redesign of the whole planform. There must also be a safe line of sight to the deck from this higher angle of attack position on approach (which has to be flown at a slower speed than a landbased plane can enjoy).
There are other constraints as well. To cite just one, there is only a fixed amount of deckspace and hangar bay area available. The engine(s) and other major components have to be able to be removed/installed in the "shadow" of the aircraft. You don't have the room to do the simpler in/out through the tail that a land-based plane enjoys. The waveoff requirements are also more sever for a carrier plane.
All of these things add weight/complexity that landbased air forces often aren't willing to accept. I'm not going to go into performance requirements, because that's more a function of mission execution design philosophy.
You can get a good plane that can operate from both land and sea in a couple of ways. First, you can adapt a sea base designed aircraft to land use. The A-1, A-3, A-7, F-4 and Buccaneer come to mind. It doesn't work that well the other way. The only ones that come immediately to mind is the FJ-2 Fury derivative of the F-86 Sabre, but a good case can be made that the F-86 inherited a good portion of its design from the FJ-1 Fury, and certain British adaptations at the start of the jet era.
Second, you can design those features into the aircraft from the start. France is doing this to superb effect with the Rafale (which as an aside I would argue is a better basic design than the Hornet E/F). It was done with the Jaguar N, but that plane died for a number of reasons, one of which was that the Adour engines kept the entire Jaguar series underpowered for its entire career, and this was especially critical for Jaguar N. They tried to do it with the F-111, but that concept was so flawed from the start and such a stupid idea to reconcile two totally incompatible roles that it would be virtually impossible even today. The F-35 will do it because it's designed in from the start. However, USAF and USMC have accepted that their versions will have to be heavier than they could have been because certain basic structural features have to be in there to allow for commonality with the USN version. It's worthy of note that had the NATF gone forward, this is not what would have happened. These would have been substantially redesigned aircraft sharing some systems. o different that both bidders envisioned building their NATFs on totally separate production lines.
The Soviets/Russians pulled if off with the SU-25, SU-27 and MiG-29 because of a couple of special factors. Even if their carrier fleet had gone on as originally envisioned, there would be a need for so few aircraft that it simply wouldn't be viable for many years to design totally new aircraft for the fleet. Second, the Soviet requirement that all of its fighter/attack aircraft be required to operate from short. rough and semi-prepared fields. They already had the landing strength and approach visibility necessary built in, could fly a controllabel approach "in the flare" and they could blast off the front end of the boat with a catapult via ski-jump (as an aside, test in the 1980s showed that all USN aircraft could as well except the S-3). The Navy was essentially told, "Since this will take off and land on a carrier, for now this is what you get".
As far the posited Sea Typhoon, that would have operated in much the same as the Soviet aircraft, STOBAR (Short Take Off But Arrested Landing). There was a big caveat though. Although it had the structural strength for repeated arrested landings, it couldn't fly the "flared" carrier approach. The idea was that some as yet non-existent flight control system would sense when it was time to flare and transition the aircraft to the right attitude at the last second (literally over the deck). I imagine a number of potential crews sort of went, "Weelll.... Can I get back to you on that"?