Methods used to overcome effects and permit high-speed flight

T-45A/C TS, ADV & IUT Aero-02

High-Speed Flight

II.

Methods used to overcome effects and permit high-speed

Sg 2, fr 2

flight 1.7.1.4.3.1

Lesson Organization

High-speed aircraft design

HIGH-SPEED FLIGHT

* Effects of high-speed

NOTE: Aircraft designed to fly at near transonic or

flight on aircraft

supersonic speeds all have features incorporated in their

* Methods used to overcome

design to delay onset of critical Mach number, reduce

effects and permit high-

wave drag, reduce or eliminate "tuck under", reduce flow

speed flight

separation, and maintain engine performance.

Sg 2, fr 3

Thickness-to-Chord

Thin airfoil sections of low thickness-to-chord ratio

Ratio

Do not accelerate the air to the extent that a

thick airfoil does

Compression wave is not as strong, once

formed

Sg 2, fr 4

Lack structural strength and volume for landing

Effect of Low

gear and fuel

Thickness-to-Chord

Ratio Airfoil on Shock

Wave Formation

Sweepback (thin wing with thick section) "fools"

air into thinking wing is a thin airfoil section

(1) Airflow broken into vector components

(a) A component perpendicular to the

leading edge contributes to lift; this

component is less than the free stream

component

Sg 2, fr 5

(b) A spanwise component does not

Fig 6: Effect of Wing

Sweep on High-Speed

contribute to lift; this component at

Airflow

high AOAs/low IAS's causes tip stalling

Sg 2, fr 6

Effect of Wing Sweep

thickness-to-chord ratio and smaller

on Drag

leading edge radius

(2) Sweepback effect on drag

(a) Reduces peak drag rise

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