The thrust to weight ratio isn’t irrelevant. It just isn’t the only determining factor in deciding if any given plane can take off from the skijump.
What determines that is whether the aircraft can attain sufficent speed, and hence generate sufficient lift, by the time it reaches the end of the skijump, to maintain controlled flight. Hence some obvious factors are:
Good acceleration (low drag airframe, and high thrust)
Minimum controllable speed of the aircraft (lower is better)
Generated lift (higher is better)
Hence an Su-25 can do it, despite its lowish T/W ratio, because its large, high aspect ratio wing will generate a lot of lift at low speeds and give it a low stalling speed.
Any modern fighter, in comparison to an older design, will hopefully be better. More advanced aerodynamics might have cut drag. Blended wing/body designs may have effectively greater lifting surface for generating greater lift. Stalling speed should be lower than for an older fighter. And, yes, they might have higher t/w ratio.
To argue thrust/weight ratio is the only deciding factor is frankly idiotic. JAS-39 Gripen has a T/O thrust to weight ratio of 0.9. Do you think it can’t take off from the Kuznetsov’s skijump? By your reasoning, it can’t.
Who here has argued that the TTW ratio is the sole factor? I’ve said, and i remain in the belive that Su-33 needs TTW ratio better than 1 to takeoff from the carrier. Is this all that it needs? No, like you and many other have said there are several factors to taken notice. The taking off is a sum of several things and lacking in one aspect needs improvements in others. In SU-33 case the cruisal element is the TTW ratio as the main variable is the take-off weight. You cannot compensate it other ways (without structual modification, which isen’t very practical to perform in the begining of every single launch) than to increase the thrust. But the engines can only generate certain ammount of thrust so the only thing left to do is to find the optimal TTW ratio by decreasing the load. Is it 0,8 or 1, never the less TTw ratio cannot be ignored.
No, but stating it without the other figures (such as Vr or Vs for instance) means its utterly meaningless. As I said, he (Conway) should have covered it properly or not at all.
I’m pretty sure that Conway didn’t ignore these other figures. Kuznetsov have three take-off stands and those lenght are know as well as the degree of the ski-jump. I’m sure (tough as it said by the wise mens, the whole statement of TTW ratio had nothing to do with the ski-jump…which I still find very odd) the book took all these variables to account when making the statement. (which as said haven’t got nothing to do with anyhting) It wasen’t talking about taking off ski-jumps in general, but exspecially from the Kuznetsovs and knowing what we and the book knew, there isen’t anything ignored. At least thats what i belive (and the wisemens have come to the conclusion that I don’t know what i’m talking about so…), I whis the book would give more on this subject…
To argue thrust/weight ratio is the only deciding factor is frankly idiotic. JAS-39 Gripen has a T/O thrust to weight ratio of 0.9. Do you think it can’t take off from the Kuznetsov’s skijump? By your reasoning, it can’t.
Well like i said, none is arguing it being the sole factor, so you can go and call someone else idiot. What comes to the Gripens ability to take off from 12 degree Ski-jump with the same takeoff lenghts as the kuznetsov (which i repeat once again is the context of all my statings), What makes you belive that it can? Yeas im’ talking about the whole thing taking all the variables to account. Has it been tested, if have, would you give me some sort of proof?
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