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From today's NAS Daily:

Boeing displays concepts for F/A-18E/F replacement

Boeing has started publicly marketing two concepts for a stealthy, tailless, supercruising strike fighter to replace its F/A-18E/F Super Hornet after 2025.
Link

That looks pretty revolutionary to me. Not that I would have any clue about aircraft design, though...

What's the idea behind such a tail-less design?
How do they ensure the aircraft's stability and maneuverability?

Zak wrote:What's the idea behind such a tail-less design?

Reduced radar cross section.

Zak wrote:How do they ensure the aircraft's stability and maneuverability?

Fly by wire. It's no different in concept than the B-2's tailless design.

JeffSFO wrote:Fly by wire. It's no different in concept than the B-2's tailless design.

That's true, but my uneducated guess is that the maneuverability requirements are higher for a fighter, compared to a heavy bomber. After all, the F-117, the F-22 and the F-35 all have tails.

IIRC, Lockheed made some experiments with a tailless F-22 variant a couple of years ago, but I never heard of any notable results.

This thing supposedly can do some maneuvers that would not be within the tolerances of a human; so the maneuverability is something that can be done without the vertical stabilizers.

http://www.century-of-flight.net/Aviati ... 0wings.htm

Pre Fly-By-Wire...

Northrop XB-35



Northrop YB-49
http://www.flight-manuals-on-cd.com/XB-49-photo.JPG

miamiair wrote:maneuverability is something that can be done without the vertical stabilizers.

Yes, but OTOH, there have been attempts to build tailless fighters before, but none ever made it into production. Assuming that there are no revolutionary new findings in terms of physics - did they just improve the software?

miamiair wrote:Pre Fly-By-Wire...
Northrop XB-35

Yep - but also a heavy bomber, not a fighter.

Improved software...

How about this:

miamiair wrote:How about this:

Wow - never saw that one before. Nice!

Again - I don't really have a clue here, just guessing - but wouldn't tail-mounted twin props deliver more stability, compared to a tailless jet aircraft?
Also, the N-9M is 'only' a scale model of the XB-35, which was designed as a bomber, not as a fighter. And it never made it into production, either.

Don't get me wrong, I'm not questioning the feasibility in general. But so far, every fighter design that made it into production featured a tail. Tailless concepts stayed just that - concepts. So my uneducated guess is that the maneuverability advantages outweighed the radar / stealth disadvantages - at least until now.

But maybe improved software will change that equation.

You're right, the props add stability, as it did with the XB-35. That is why the YB-49 had several small vertical stabs, where the -35 was clean.

Zak wrote:my uneducated guess is that the maneuverability requirements are higher for a fighter

Not necessarily in the yaw axis, pitch and roll are much more important now than is yaw. And who's to say asymmetric split aileron deployment can not be as or more effective than a vertical control surface anyway? Engagement envelopes for missiles are getting bigger all the time so maneuverability of the launch aircraft is taking a back seat to more advanced fire control systems and better stealth technology.

Zak wrote:After all, the F-117, the F-22 and the F-35 all have tails.

True, but they have what could be seen as "primitive" flight control systems and software compared to what's available now.

Queso wrote:

Zak wrote:After all, the F-117, the F-22 and the F-35 all have tails.

True, but they have what could be seen as "primitive" flight control systems and software compared to what's available now.

The f-22 and company are "new" to everyone, but consider most of the technology actually driving the thing is 10-20 years old at this point.