Just seen a multiple choice question, and wondered the answer.
What first made sustained flight near and beyond the speed of sound possible?
a) jet engine
b)The supercritical wing section
c)Area-ruling
I don’t know what b or c even are?
Thanks very much guys
A supercritical airfoil is an airfoil designed, primarily, to delay the onset of wave drag in the transonic speed range.
The Whitcomb area rule, also called the transonic area rule, is a design technique used to reduce an aircraft’s drag at transonic and supersonic speeds, particularly between Mach 0.8 and 1.2. This is the operating speed range of the majority of commercial and military fixed-wing aircraft today.
The first aircraft to break the sound barrier was rocket-powered, not jet propelled. research the XLR-11 rocket engine
November 25th, 2009 at 10:55 am
Well, you know what a jet engine is – and that’s the correct answer. Ain’t no way a propeller driven plane is going to break the sound barrier.
References :
November 25th, 2009 at 11:23 am
A supercritical airfoil is an airfoil designed, primarily, to delay the onset of wave drag in the transonic speed range.
The Whitcomb area rule, also called the transonic area rule, is a design technique used to reduce an aircraft’s drag at transonic and supersonic speeds, particularly between Mach 0.8 and 1.2. This is the operating speed range of the majority of commercial and military fixed-wing aircraft today.
The first aircraft to break the sound barrier was rocket-powered, not jet propelled. research the XLR-11 rocket engine
References :
November 25th, 2009 at 12:10 pm
The supercritical wing section is designed to delay the formation of shockwave on the upper surface. It has low thickness/chord (finess) ratio to reduce acceleration on upper surface therefore delaying shockwave (when the upper air flow reaches Mach1) so the airplane can fly at a higher speed without significant increase in drag due to shockwave.
It has a highly cambered aft section to provide more lift.
References :
ATPL aerodynamic
November 25th, 2009 at 12:16 pm
The answer is C. Answer A is incorrect because it wasn’t a Jet engine that first broke the sound barrier, it was a rocket engine. Answer B is incorrect because Chuck Yeager broke the sound barrier on Oct 14, 1947. Supercritical airfoils weren’t designed until the 1960s by Richard Whitcomb, and were first tested on the TF-8A Crusader.
Area-Ruling was discovered by Otto Frenzl in Germany between 1943-1945. It was this that lead to the design of the Bell X-1, and the ability to break the sound barrier.
References :
Wikipedia