- Joined
- 17 October 2006
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LowObservable said:The 3,750 lb weight for the F135 would be stellar if it were true, but it is a little suspicious. A P&W fact sheet gives the not-to-exceed weight as 6500+ pounds and it was more recently confirmed as 6444 pounds by P&W.
LowObservable said:A single lift-cruise engine is pretty much mandatory for STOVL, so I would be the last to recommend a sort of double-Mamba arrangement for SDLF.
But if we're on topic here, NGAD/F/A-XX is not STOVL so the question is how to provide the best performance for that mission.
Steve Pace said:The on again-off again and now cancelled GE F136 might fit the bill - two of these equals 80,000 pounds total thrust. -SP
jsport said:It is a sad state when after hundred yrs of Naval Aviation a two engine STOVL can be developed to cover all missions including CAS in a A2AD environment.
jsport said:Two clo se set engines would be a superior design to all other designs
Stack the engines on top of each other English Electric Lightning fashionLowObservable said:....The only way to avoid that would be to make the STOVL twin capable of withstanding a power loss - but that would mean a VL thrust/weight ratio of 2:1 and some means to avoid asymmetry, and nobody has figured out how to do this.
GTX said:NUSNA_Moebius said:If the engine is derived from the F120 (which I understand it is), there certainly is quite a bit of potential. The idea behind the F120 certainly is superior to the F119, but execution is another, especially since a variable cycle engine is pretty much guaranteed to be more expensive. While I also know the YF120 was used in high AoA tests with the YF-22, I do wonder about how stable the engine is and it's reliability in extreme maneuvers.
If you are referring to the F-136' then it was NOT a derivative of the F120 but rather an entirely new engine developed jointly by Rolls-Royce and GE.
AeroFranz said:As far as stacking the engines, you have to provide a good location for the nozzles - i.e., the top nozzle can't go through the bottom engine or something like that. So you have to stagger them longitudinally (preferable) or laterally (one more 90 degree bend, so more duct losses). Stagger introduces a moment arm to the c.g. that in the case of engine out translates to a pitching or rolling moment that in a twin engine aircraft would be massive - you lose all thrust on one side while simultaneously having to provide twice as much on the other. My hat's off to you if you can figure out a layout that works.
I can't remember how the X-14 was supposed to cope with engine-out. I'm thinking of it because it was a twin with closely spaced nozzles. It may not have been designed with the capability, and as a result probably had a 'dead-man's' curve.
anyway, the laws of physics being what they are, I think it's pretty tough to come up with any new working layout that hasn't been thought of in the sixties. There is the possibility to make some work better provided breakthroughs in key technologies, like vastly better power-to-weight in batteries, high power electrics, small gas turbines, etc.
flateric said:'to fix?'
flateric said:Triton, why so serious? perspective view and symmetry seems to be so distorted at original photo that attempt to fix it looks like rolling over a possum smashed down at the highway and saying that now 'it's fixed'
A Northrop Grumman artist’s conception of a sixth generation fighter employing directed energy weapons and stealthy data networking. (Northrop Grumman illustration)
bobbymike said:DOD: Edge To 'Shift Against' U.S. Without 'Near-Term' 6th-Gen Fighter Without "near-term" plans to launch a sixth-generation fighter aircraft program before 2030, the Defense Department estimates the U.S. aerospace industry could forfeit what is believed by the U.S. government to be a five-year technological advantage over foreign combat aircraft makers, according to a previously unreported Pentagon assessment.
dark sidius said:If Air force stay with the 5th gen fighter soon they lost there superiority on the foreign air force, look the Chinese they run very well on new generation and soon they will compete with the US fighters a 6th gen fighter is vital for the superiority of USAF without that Chinese in ten years will dominate the world with all the consequence on the world economy Hurry up USAF to launch a new fighter. F-35 have too poor capacity to dominate futur T-50 and J-20.
1st503rdSGT said:FWIW, I'm guessing the NGAD fighter (a Navy program BTY) will probably end up being nothing more than a later-block F-35C.
dark sidius said:Ok don't invest and we will see.
TaiidanTomcat said:But I wish you the best of luck, as someone who has been fighting an uphill battle to justify fifth generation fighters to folks who think they are unneeded for sometime myself I can tell ya youll have an awful lot of convincing to do.
dark sidius said:Yes and see the events today and look just a country like Iran everybody are afraid to make a raid so imagine in China or Russia. Ok don't invest and we will see.
Matej said:And what exactly is that 5th generation?
Matej said:why Europe should replace its new Eurofighters and Rafales with a new design in a near or mid term? Why? What they cant do or with new equipment (Meteor, PIRATE,...) wont be able to do from a list of tasks of their operators? Some child want to have a cooler poster on his wall? Well, that's really a good reason to spend billions of Euro.
Matej said:And what exactly is that 5th generation? I remember times some 15 years ago, when YF-22 was all the time described as 4th generation plane, because in US, fighters were organized just to four generations while in Russia/SSSR into five.
chuck4 said:Possibly because after T-50, J-20 and J-30 hits the arms market, you will not longer be able to sell anything to anyone. Which would be a pity.
sferrin said:As far back as I can remember (at least late 80's or so) the F-teen series was always referred to as 4th generation.