Northrop YF-17 WHIF

[KJ_Lesnick]

Evan,

Actually, the interesection of chine and fuselage is probably close to that of any of the F-18 variants, the sharp edge of the chine coming in, from a tight turn, normal, or nearly so, to the fuselage at that station.

Understood.  I was just trying to get a mental-picture

Either way could this kind of contouring have been done back in the days the YF-16 was being created?  Or could this have only been done later on (when this revised chine was proposed)?


KJ Lesnick

[elmayerle]

Only if you got a "cross-pollination" of ideas from Northrop to GD-Ft. Worth, most likely by movement of personnel - specifically those personnel familiar with the work Northrop was doing with vortex flow.  I rather suspect Northrop would go to great lengths, at that point in time, to retain those folk.  Since a lot of this was company proprietary data, I doubt there'd be much chance of one of the armed services transferring that information.  Much like a lot of the hard-won knowledge that both Lockheed and Northrop had, by the early 1990s, in low observables technology was proprietary and thus couldn't be transferred to the GD-McD team for use on the A-12.

[KJ_Lesnick]

Evan,

Only if you got a "cross-pollination" of ideas from Northrop to GD-Ft. Worth, most likely by movement of personnel - specifically those personnel familiar with the work Northrop was doing with vortex flow.  I rather suspect Northrop would go to great lengths, at that point in time, to retain those folk.  Since a lot of this was company proprietary data, I doubt there'd be much chance of one of the armed services transferring that information.  Much like a lot of the hard-won knowledge that both Lockheed and Northrop had, by the early 1990s, in low observables technology was proprietary and thus couldn't be transferred to the GD-McD team for use on the A-12.

Still, I'm surprised that Northrop would be the only people that would know that rounding off a highly swept surface could be done to prevent a pitch-up.  For example, in 1964, Lockheed, realizing that it's SST-design, the L-2000 (which was a double delta) had a pitch-up tendency at high angles of attack, revised the forward-delta by rounding the forward delta off which cured the problem.

The F-16's deep-stall problem was more or less a pitch-up problem caused by the LERX producing disproportionately high lift at high angles of attack.


K.J. Lesnick

[KJ_Lesnick]

Regarding the Northrop YF-17 WHIF idea I was thinking about. 

Assuming you had the Preliminary or Advanced Design people at Northrop come up with an idea for the shark-nose.  Where would the LERX join the fuselage?  Would it be the same as on the YF-17?  Or would they be further back on the fuselage?

Secondly, even though the LWF program was initially proposed as (or at least made to appear as if they were) testbeds.  Was there anyway the USAF, reasonably speaking, could have been convinced or persuaded that a single-engined design would be all that would be necessary for a lightweight fighter design (for one, it's a lightweight design and it doesn't need two engines to get a high T/W ratio, and two, there are already off the shelf engines such as the F100 that produce the desired thrust/weight ratios for such a light-plane)?


KJ Lesnick