Stabilty of early delta wing jets

Several companies during the postwar period produced tailless delta jets. Notable examples include the Convair XF-92A, F-102 and F-106, Dassault Mystère Delta and Mirage series, Avro 707, Fairey Delta 2 and probably others. How did they avoid instability in pitch? The simple way is to move the centre of mass forward and angle oversized elevator/elevons up a bit, mimicking an aerofoil with zero or backward movement of the centre of pressure with pitch. But that is a high-drag, low-wing-loading solution. Next comes a genuine zero-shift aerofoil with negative camber on the rear section, slightly less draggy but still inefficient. Most complex to engineer but most aerodynamically efficient is the use of reduced-incidence "washout" towards the wing tips. I can't find anything relating to this in any discussion of these designs, and all the wings are so long and thin that it is impossible to tell from photographs. I am particularly interested in the Fairey Delta 2, but enlightenment on any of these types would help.

Conical camber on the wing leading edge of the Convair Designs: F-102/F-106/B-58

http://www.globalsecurity.org/wmd/systems/b-58-design.htm

From the link above:

Conical camber was employed in the leading edge to reduce drag at lifting conditions and thus increase cruising efficiency. (A conically cambered wing is one which has a leading-edge camber shape formed from part of the surface of a cone whose apex is located at the longitudinal plane of symmetry of the wing. The amount of camber accordingly increases progressively with spanwise distance from the fuselage.) Absence of a horizontal tail for trimming prevented the use of any trailing-edge high-lift devices.

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Of course, Convair was just copying earlier work on stable delta wing flight vehicles.

Interesting that Convair used the classic Dunne solution. I wonder if Fairey did too.

Sadly the paper dart is not an equivalent design - a flat plate is aerodynamically stable. A number of straight-wing tailless flat plate designs were flown, ISTR by a Frenchman, at around the time Dunne was flying his more practical solution.

Any serious paper airplane builder knows that adding leading edge camber greatly improves stability and L over D. For an 8 1/2 by 11 piece of paper, a pencil provides just the right radius.

You might find what you are looking for in "The Delta Wing" by Alexander Lipppisch.


From the description on Amazon:


"The Operation Paperclip program imported Nazi scientists and engineers to America so that they could work on post-war aviation and aerospace. Of this talented group, Alexander Lippisch was one of the most acclaimed and certainly one of the most accomplished. An aviation pioneer, his most famous aircraft was the rocket-powered Messerschmitt Me 163.


Richly illustrated with rare photographs and drawings, this book describes the development of new [Delta Wing] methods, including the calculation of wing profiles, determination of lift distribution, and refinement of aircraft design for higher performance..." Lippisch details his research methods, his experiments, and his use of flying models. His conclusion: an airplane without a tail is equal to and sometimes superior to standard airplane designs."


http://www.amazon.com/Delta-Wing-History-Development/dp/0813805155/ref=sr_1_1?s=books&ie=UTF8&qid=1414476687&sr=1-1&keywords=Delta+wing

Thanks, that's just what I need! I had no idea it existed.

I'll see if my local library can get hold of a copy. Costs a fiver, but I certainly can't afford £85 plus to buy even a dog-eared secondhand copy.

steelpillow said:

I'll see if my local library can get hold of a copy. Costs a fiver, but I certainly can't afford £85 plus to buy even a dog-eared secondhand copy.

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Dunno why the forum software insisted I look at this thread.
But here about 9 years later in 2023 I will contribute this,
The price range per listed condition is interesting.

The Delta Wing: History and Development
Hardcover
1 rating
Used - Like New
$999.00
$3.99 delivery June 1 - 6. Details

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and another one,

Collectible - Acceptable
$59.99

FREE delivery June 6 - 12

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I fed Ein Dreieck fliegt to bookfinder.com, author Alexander Lippisch, language German.
24 on offer, prices from €55,00 to €161,31.

Unfortunately @steelpillow has left an gone away (like Joe di Maggio, champion Joe)

Archibald said:

Unfortunately @steelpillow has left an gone away (like Joe di Maggio, champion Joe)

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You can always drop me a PM. I have only withdrawn from the public discussions.

Good to know ! Duly noted.

I'm guessing those four figure prices are algorithm generated. Looks like you might be able to buy a copy for $50-$60