Gr.Viper 131 Posted September 18, 2009 Take a look at the pics Pity, those test planes couldn't hover MiG-21PD http://www.airwar.ru/enc/xplane/mig21pd.html MiG-23PD http://www.airwar.ru/enc/xplane/mig23pd.html Share this post Link to post Share on other sites
+Spillone104 553 Posted September 19, 2009 The Mig-23PD have the best look. But on the serie of super STOL we have to add the Sukhoi T-58VD based on the Su-15 Share this post Link to post Share on other sites
the test pilot 5 Posted September 20, 2009 they seem to be an interesting concept. But i guess they weren't much efficient, am i wrong? Share this post Link to post Share on other sites
+Spillone104 553 Posted September 20, 2009 they seem to be an interesting concept. But i guess they weren't much efficient, am i wrong? As all aircraft that used lift engines.... the engine is dead weight in flight and take away precious space to fuel. Share this post Link to post Share on other sites
FastCargo 412 Posted September 20, 2009 It didn't help that the 'lift engines' themselves weren't very powerful or efficient...which means you needed more of them...which adds to the weight... You get the idea. The technology of the time simply wasn't good enough. That's why though there have been a lot of attempts, the Kestrel/Harrier has been the only real 'successful' (in terms of production numbers) VTOL capable fighter. FC Share this post Link to post Share on other sites
+Gepard 11,323 Posted September 20, 2009 The 21PD was the testbed for the 23PD. It was unable to retrieve the gears and their pilots said it was a nightmare to fly. The 23PD was canceled in favor to the swing wing design. It had nothing to do with the technology. It was a problem of additionally weight. The lift engine concept was used successfully on the Jak-38 Forger and the Jak-41 Freestyle. The F-35 VTOL fighter use the same concept which has proofed much more stable and reliable to fly than the Harrier system. The major point is the better transistion from vertical flight to level flight. In the Harrier it is a little bit tricky and some pilots lost their live in transistion related accidents. Not one single Jak-38 was lost while transition. But it is true, that the Harrier was the better plane. Share this post Link to post Share on other sites
FastCargo 412 Posted September 20, 2009 I'm an idiot...I forgot about the Forger which did use a liftfan system. I don't count the Freestyle since it never went into production. The liftfan in the X-35 was superior in performance to the X-32 direct lift system...not just in total thrust potential, but also because the X-35 system suffered less from hot air ingestion. FC Share this post Link to post Share on other sites