delta wing?

[Frosty Hoar]

Since concorde amongst others has demonstrated to us the effectiveness of the delta wing, e.g. high speed range without incurring the complexity and expense of moving t.e. and l.e. devices I just wondered why the swept wing is favoured over the delta in modern passenger aircraft.


rgds FH.

[speedbird_heavy]

Probably to do with the high angle of attack during low speed manoeuvres and because of this a lot of power was needed to keep the aircraft flying. Lots of power equals noise and people don’t like noise. The Concorde B model had leading edges designed into it

[Mad (Flt) Scientist]

The delta's advantage lies more in the supersonic area than anywhere else; for high subsonic flight a "conventional" swept wing should outperform the delta.

[oxford blue]

Hey, Mad Scientist, what about the Vulcan? That was (just) subsonic but handled like a dream and turned (especially at high altitude) tighter than any fighter.

It all depends on how you define 'outperform'.

[Intruder]

Not to mention the A-4 Skyhawk...

[Mad (Flt) Scientist]

Well, neither of those are really passenger aircraft, are they. Sustained or instantaneous rates of turn don't help much in airline economics.

One big disadvantage of the delta for commercial ops is something cited as an 'advantage' - ne l/e or t/e devices.

With a wing-plus-tail I can put all kinds of advanced high lift systems on the aircraft and get a vast improvement in field performance. With a pure delta I'm limited by the need to use the t/e for pitch control.

That's going to hurt the economics of the delta for two aircraft operating in the same environment - unless you're operating off very long runways the delta is going to be MTOW-restricted more often.

[18-Wheeler]

With a pure delta I'm limited by the need to use the t/e for pitch control.

Nope, though only just
The Mirage 2000 has LE devices, and they would have to be balanced with increased lift at the rear of the wing.

http://archive.cs.uu.nl/pub/AIRCRAFT-IMAGES/Mirage-2000.jpg

[Intruder]

One big disadvantage of the delta for commercial ops is something cited as an 'advantage' - ne l/e or t/e devices.
Maybe in the old, "pure" delta designs (e.g., F-102)... However, delta wings preclude neither L/E and T/E, devices nor a horinontal tail. The A-4 had all 3...

OTOH, stall characteristics might preclude certification, unless fancy fly-by-wire stall-recovery aids are incorporated...