See also the YC-14 and the An-72. Looks like Kawasaki went for more span for Coanda effect advantages and that document mentions the reduced wing area offered cruise efficiency gains.
Why hasn’t this configuration need developed further?
Maintenance nightmare, while realistically planes like the C-17 and C-130 are STOL enough for most purposes. Plus there's the general resistance from those in charge of military procurement to new configurations in favor of the tried-and-true.
I'd guess that the improvements that it offers are marginal at best, while the engineering needed to put the engines out ahead like that aren't worth the effort in the long run.
There are turboprops that have been designed to use the effect too. The An-32 I'm fairly certain used it to enable high-and-hot operations, and I think the DHC-7 might have used it to enhance it's STO capability.
These are low by pass turbo jets, that will still be making most mass flow from the turbo fan.
With hybrid electric aircraft, shorter cord EDF can be used powered by a high efficiency turbine with a much higher effective by pass ratio, using more upper wing surface area blowing, plus a tail fan. As the speed increases you might want to alter the wing fan position to clear the wing. That would require a new control mechanism that would lift up or down the fans and some sort of exhaust flow shaping exit duct.
Dangerous-Salad-bowl@reddit
See also the YC-14 and the An-72. Looks like Kawasaki went for more span for Coanda effect advantages and that document mentions the reduced wing area offered cruise efficiency gains. Why hasn’t this configuration need developed further?
Arbiter707@reddit
Maintenance nightmare, while realistically planes like the C-17 and C-130 are STOL enough for most purposes. Plus there's the general resistance from those in charge of military procurement to new configurations in favor of the tried-and-true.
mizunumagaijin@reddit
I'd guess that the improvements that it offers are marginal at best, while the engineering needed to put the engines out ahead like that aren't worth the effort in the long run.
There are turboprops that have been designed to use the effect too. The An-32 I'm fairly certain used it to enable high-and-hot operations, and I think the DHC-7 might have used it to enhance it's STO capability.
CrouchingToaster@reddit
Looks like a bunch of T-shirt cannons
wordsmith7@reddit
More weird ass engines? Yes.
55pilot@reddit
The airplane sucks X 4.
LightningFerret04@reddit
Well no chance of fod here, very interesting aircraft
PostwarVandal@reddit
He'll still have to watch out for giraffes on the runway.
Smooth_Imagination@reddit
These are low by pass turbo jets, that will still be making most mass flow from the turbo fan.
With hybrid electric aircraft, shorter cord EDF can be used powered by a high efficiency turbine with a much higher effective by pass ratio, using more upper wing surface area blowing, plus a tail fan. As the speed increases you might want to alter the wing fan position to clear the wing. That would require a new control mechanism that would lift up or down the fans and some sort of exhaust flow shaping exit duct.
Clickclickdoh@reddit
The Asuka QSTOL was a really interesting research program:
https://www.icas.org/ICAS_ARCHIVE/ICAS1990/ICAS-90-2.7.2.pdf
ban-rama-rama@reddit
I see room for at least three more motors in there, shame on you Kawasaki.