Part 8 (2/2)
The velocity is now still less by reason of the increased angle producing increase of drift Less velocity at a given angle produces less lift, but the increased angle more or less offsets the loss of lift due to the decreased velocity; and, in addition, the thrust is now hauling the aeroplane upwards
MAXIMUM ANGLE
The greater angle has now produced so much drift as to lessen the velocity to a point where the combined lifts from the surface and froht Any greater angle will result in a still lower lift-drift ratio The lift will then becoht and the aeroplane will consequently fall
Such a fall is known as ”stalling” or ”pancaking”
=NOTE--The golden rule for beginners: Never exceed the Best Cli speed of the aeroplane=
SUMMARY
_Essentials for Maxie surface
3 Large angle relative to propeller thrust
4 Large angle relative to direction of e cah velocity
2 Sle relative to propeller thrust
4 Sle relative to direction of motion
5 Small camber
It is mechanically iht of which it would be possible to vary the above opposing essentials Therefore, all aeroplanes are designed as a compromise between Clined to have at low altitude a slight in of lift when the propeller thrust is horizontal By this in of lift disappears (on account of loss of engine power), and which is, consequently, the altitude where it is just possible towith its thrust horizontal and with ine and propeller efficiency)
The in of lift at low altitude, and when the thrust is horizontal, should then be such that the higher altitude at which the in of lift is lost is that altitude at which ht work is done That ensures maximum velocity when ned for fighting are concerned, the altitude where most of the work is done is that at which both in of lift for power are required
Perhaps son an aeroplane of reasonable weight and drift of which it will be possible for the pilot to vary at will the above-et in of lift, for power as required
Until then the design of the aeroplane must remain a compromise between Velocity and Climb
[Footnote 14: See Newton's laws in the Glossary at the end of the book]
[Footnote 15: See ”Aerofoil” in the Glossary]
CHAPTER II
STABILITY AND CONTROL