Talk:Delta wing
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[edit] Advantages
"The primary advantage of the delta wing design is that the wing's leading edge remains behind the shock wave generated by the nose of the aircraft when flying at supersonic speeds, which is an improvement on traditional wing designs."
Isn't this just a matter of the sweep rather than the delta planform? For example, the English Electric Lightning and MiG-19 have rather severe leading edge angles for this reason, even though they are not deltas. -- Paul Richter 09:52, 22 Nov 2004 (UTC)
The delta wing has much the same advantage as the swept wing:primarily a delay of critical mach of 1/cos(angle of sweep)
The wing is as if it were flying at reduced speed, reduced Mach number, and reduced dynamic pressure.
effective speed = V cos(L) effective Mach = M cos(L) effective q = 0.5 rho V^2 [cos(L)]^2
where L is the sweep angle, V the airplane's speed and M its Mach, rho the air density and q the dynamic pressure.
The dynamic pressure term shows that the wing will have not only reduced drag but also reduced lift since:
Lift = Cl x A x q where Cl is the coefficient of lift and A the Area Drag = Cd x A x q where Cd is the coefficient of drag and A the Area
Suppose a swing wing aircraft is flying at its critical Mach number. If the wing then is swept back from 0 to L degrees the lift reduces by a factor of [cos(L)]^2, and the Mach compressibility effects on the wing's airfoils decrease eg shock wave formation. It is then possible to increase the speed by a factor of 1/cos(L).
These are simplifications for a swept wing; deltas are similar but far more complicated in real life due to the formation of vortices at the leading edge root that has a positive influence on handling and lift.
[edit] Alexander Lippisch
I don't know why Dr Alexander Lippisch is not mentioned in regards to the Delta wing: he had developed flyable swept wings in the 1930s and 1940s and proposed a surpersonic delta in 1940. In 1945 his DM-1 glider was shipped to the USA for study. His P.13a represents perhaps the first proposal to develop a supersonic delta.—Preceding unsigned comment added by Frederick Munster (talk • contribs)
You are right. The reference to Neythen Woolford is a furfy I believe. He is a kid on facebook and appears in no other published histories of Delta wings I have ever read. I'm suspect someone has vandalised the entry and sustituted their own name to achieve notoriety. It is demonstrable that Lippisch was the pioneer of Delta wings in Germany prewar and postwar GregOrca (talk)
[edit] Carnard
The explanation of the canard in the 3rd paragraph is a bit confusing. I've cleaned up the language a bit, but the point is still unclear. Attributing designs incorporating canards to unstable platforms and FBW doesn't seem accurate. The F-117 and F-16 are inherently unstable and neither have canards. FBW and instability (due to more radical, effective designs) do exist symbiotically these days, but that is independent of canard use. While the EF-2000, Rafale, etc. are more advanced designs and use canards, that has more to do with the increased effectiveness of delta-wing aircraft with canards, not necessarily instability or FBW.--Jonashart 20:13, 27 July 2006 (UTC)
- That 3rd paragraph reads much better now. Sorry, took a while to get back to reading it. Nicely done, whomever is responsible.--Jonashart 15:44, 19 April 2007 (UTC)
[edit] Reorganise?
The article seems to alternate between historical ordering and description.
Perhaps the better structure would be:
- history
- before WWII
- later development
- current status
- discussion
- advantages
- disadvantages
- list of types
m.e. 05:25, 24 November 2006 (UTC)
Support. - BillCJ 05:41, 24 November 2006 (UTC)