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Old 10-07-2014, 03:16 PM
  #881  
Zor
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Join Date: Feb 2009
Location: Ontario, ON, CANADA
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Default Some comments _ _ _

Addressed to the general reader ( viewer ) which includes participants.

Do not be surprised to read objections to my following comments.
If objections are posted I hope they will point to specifics and offer a correction with explanations.

Comments

Stalling is not the results of heavy weight ( high wing loading ). It is the result of exceeding the stalling angle of attack of the wings. That can happen at any wing loading. The wing angle of attack is self adjusting in any specific flying condition.

Airliners with high wing loading can glide at about the same angle of descent as light airplanes do. The difference is in the speed of travel.

A relationship, as one example, is that at twice the weight the speed has to be 1.41 times faster.

There is a method of judging the final approach angle of attack by looking at the horizontal tail surface versus the main wings. That is determined by observations while practicing stalls at sufficient altitude in level flight. Rarely is the angle of attack of the main wings more than 6 to 8 degrees on a stable approach rate of descent. This is where the setting of the decalage and the CG location is important.

At cruising speed the elevators should be neutral in line with the stabilizer while the airplane is not climbing and not descending ( level straight flight ). We should choose an engine to establish cruise speed at about half throttle opening of the carburetor ( not the transmmitter stick position ).

Note that I am not talking about airplane shaped helicopters _ _ _ aka _ _ _ 3D flying.
I am talking about normal realistic model airplane flying including patterns and aerobatics.

Some crash damage reduction methods.

A compression strong component from the firewall to behind the wings trailing edges.
This or these components can often be used as the engine mount.

A high compression resistant component between the wings leading edge and trailing edges to reduce or prevent the fuselage from breaking inward.

A high tension resisting component at both the wing leading edges and trailing edges to reduce or prevent the fuselage from breaking outward.

Some hard wood component in the fuselage structure to the tail assembly with diagonal crossings to reduce break away of the fuselage behind the wings.

A covering material resistant to tearing with a surface finish that does not affect the strength of the covering material.

I invite anyone to add to these basic principles.

Zor