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The Concorde's baby - new supersonic commercial aircraft

Wick said:
That is a very low lift wing which means a high take-off speed, so either very rapid acceleration or a very long runway, and then there is the extra oomph required to go trans-sonic. I shall watch with interest!
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I'm not sure I follow. Can you explain what you mean by 'low lift wing'? Deltas generate lift in a different way to conventional aerofoils, but I don't think I've ever thought of them as a low lift option.
 
Sue Pertwee-Tyr said:
I'm not sure I follow. Can you explain what you mean by 'low lift wing'? Deltas generate lift in a different way to conventional aerofoils, but I don't think I've ever thought of them as a low lift option.
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At low speeds, thin supersonic deltas generate little lift, so require the classic high angle of attack on approach, for example. The generate enough lift at supersonic speeds to fly in low drag, straight and level.
 
As an aside, one of my favourite delta aircraft is the B-58 Hustler. This, copied from Wikipedia:

"The B-58 set 19 world speed records, including coast to coast records, and one for the longest supersonic flight in history. In 1963, it flew from Tokyo to London (via Alaska), a distance of 8,028 miles (12,920 km) in 8 hours, 35 minutes, 20.4 seconds, averaging 938 miles per hour (1,510 kilometres per hour). As of 2016, this record still stands. The aircraft was serving in an operational unit, and had not been modified in any way besides being washed and waxed. One of the goals of the flight was to push the limit of its new honeycomb construction technique. The speed of the flight was limited only by the speed at which they believed the honeycomb panels would delaminate, although one of the afterburners malfunctioned and the last hour of the flight was continued at subsonic speed. This reduced the average speed to roughly Mach 1.5, despite most of the flight being at Mach 2. This B-58 was called "Greased Lightning" – the codename for the record attempt."

That's something very special to this day.
 
At low speeds, thin supersonic deltas generate little lift, so require the classic high angle of attack on approach, for example. The generate enough lift at supersonic speeds to fly in low drag, straight and level.
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Thanks Tony, I thought that might be it, and its just the inevitable corollary of the way deltas generate lift and the consequent reliance on AoA, but thinking about this the other way round, it's lift 'envelope' has to cover a much wider range of airspeeds than a conventional wing, which doesn't really make it a low-lift design so much as a design which operates over a much wider range of airspeeds. It merely trades a degree of low speed capability for a much greater top speed. I may be mistaken, but I expect it could generate sufficient lift for takeoff at conventional takeoff speeds, but the AoA might be a bit scary, and you might well be on the back of the drag curve, somewhere you don't want to be on takeoff, or when close to the ground.
 
Tony Lockhart said:
At low speeds, thin supersonic deltas generate little lift, so require the classic high angle of attack on approach, for example. The generate enough lift at supersonic speeds to fly in low drag, straight and level.
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Yes, seeing a SAAB Draken (or the Vulcan) land illustrates this very well.
 
Sue,

Probably getting into specific aircraft there. C of G, C of Pressure, all sorts coming into play.

Modern avionics make scary low speeds at high angles quite routine now.
 
Back to raw excitement, 1959 air show style. I'd pay good money to see the modern version of this:


A few deltas, and then just wait for the....... oh, you'll see :)
 
In simple terms,
High-lift wing = good for low speed flight (think C-130 Hercules) but way too much drag for faster flight.
Low-lift wing = good for high speed flight (think Concorde, and the venerable Lightning interceptor) and low drag to make speed possible.

At the fringes of the design envelope, for example take off and landing speeds, then big compromises have to be made by low-lift wings to ensure control, stability and a safe transition between air and ground.
 
that Supersaver target missile...we are in the late 50s so no computers and stuff I presume....how does the second missile find it?

I find nothing when I google Super Saver etc?
 
Wick said:
In simple terms,
High-lift wing = good for low speed flight (think C-130 Hercules) but way too much drag for faster flight.
Low-lift wing = good for high speed flight (think Concorde, and the venerable Lightning interceptor) and low drag to make speed possible.

At the fringes of the design envelope, for example take off and landing speeds, then big compromises have to be made by low-lift wings to ensure control, stability and a safe transition between air and ground.
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Thanks, I do understand that, but the Concorde wing and the Lightning wing are fundamentally different. I just think that describing a delta design as a low lift wing (on the grounds that one design parameter is very high speed operation) is to oversimplify unhelpfully.
 
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