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As far as I know, tailless delta wings have the worse energy retention during a turn, is that true? If yes then why is that the case?

Also jets like F16 with root extended shallow delta wings (40% delta) are reputed to have higher energy retention, at least that's what I have concluded for the EM diagrams of F16.

Why is that the case and what wing design will be the best in energy retention?

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  • $\begingroup$ Really, sailplane wings have the best energy retention due to high aspect ratio. But the reason you can't build a fighter jet like a sailplane is because fighter jets make sharp turns and go supersonic so you run unto structural issues due to limitations of material strength. So its not about best. It's about how much you are willing to compromise so you don't get shot down. $\endgroup$
    – DKNguyen
    Commented Jan 30 at 17:01

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This is not a matter of wing type -- instead a matter of wing and aircraft design.

An aircraft designed for maneuvering might be designed such that it achieves maximum L/D in the midst of a combat turn -- say 3 g's at M=0.9 at 30,000 ft.

You of course want that L/D to be high, but beyond the wing type, this means setting the wing area such that the wing loading (W/S) is such that the above condition is met.

If an aircraft is instead designed to reach maximum L/D at 1g flight, it will likely suffer during maneuvers. Particularly for a low aspect ratio wing that has relatively high induced drag.

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  • $\begingroup$ So you are saying that energy retention is a matter of optimisation? I can't get how this optimisation is achieved, according to what I have found jet with same Aspect Ratio, Wing Loading, Leading Edge angle might differ significantly is performance (Turn Rate to be specific) even commercial airliners with the same engine and wing design differ in cruising efficiency, stall speed, Corner speed and all, is there any other property of a wing that I am missing? $\endgroup$ Commented Jan 31 at 15:31
  • $\begingroup$ You seem overwhelmed with the wing properties you already have -- why do you want to add more to the list? Everything in aircraft design is a matter of optimization and tradeoffs. You need to start with the equations and understand what they're telling you. Look into sustained turns. $\endgroup$ Commented Jan 31 at 17:20
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NO wing design is absolutely perfect in the configuration for what describes a fighter. In persepctive a "Delta" swept back wing makes Better interceptors and wider broader wings make better dogfighters. THEY figured this out a long time ago. It's not a question of "Best" it's what you're thinking of in regards, Do you want, speed? or Chinking (Maneuverability)

Back then the Fighter mafia which was a group of controversial outside the Pentagon bureaucracy think group including Colonel John Boyd, Pierre Sprey... In mid 60s they gained access to early computer mainframe and calculated a series of equations to defer mix of full embodied energy in a plane (Fuel) and equate how well that energy could be utilized either to be fast or be manueverable. Called it EM or Energy-Maneuverability Theory. Using what essentially was early attempts "PHysics" engines in computer and man made calculation they released a 2 volume report to the US Air Force and data provided by testing of KOrean and Vietnam era aircraft provided data Air Force to design criteria for it's next generation of planes which became the "Teen Series" which gave rise to the F15 and F16.

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  • $\begingroup$ What is "chinking"? $\endgroup$ Commented Feb 1 at 11:53
  • $\begingroup$ This could use an edit for clarity, reduction of raNdom caPs and readability $\endgroup$
    – FreeMan
    Commented Feb 1 at 13:17
  • $\begingroup$ @quietflyer "Jinking" is the more usual spelling. "To move quickly or unexpectedly with sudden turns and shifts" (Merriam-Webster). $\endgroup$
    – Tevildo
    Commented Feb 3 at 16:35

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