Airplane Design

Airplane Design requirements

1. Point out on rough diagrams or on photographs, the outstanding differences in design of full scale planes used for five rather widely different purposes - such as first training, commercial transport, seaplanes on northern lakes, clippers, pursuit or others.

2. Measure the silhouettes of five modern full scale planes and record range of variation in the ration of wing span to chord (aspect ration); also in wing area as compared to stabilizer-elevator area.

3. Show design differences in camber of wings for high life and for high speed - use rough sketches to explain reasons.

4. (a) Find approximate location of center of gravity in a flying model, and explain why a low center of gravity contributes to parasol stability; (b) if a model plan is balanced and wings of same chord, but of added span and weight were substituted at same structural points, tell what the plan would then tend to do in flight.

5. Show by rough sketches why dihedrals, sweep-backs and relatively high wings tend to give model stability in flight.

6. Build, test and report flight performances of two flying models of same general size, but of quite different design. For the test, use same power plant and propeller. If desired, the Scout may build but one of the two test planes, matching it against one he or his friends have, AND then offer as the second of the two to be built, an original unconventional or experimental flying model.

7. Prepare approximate or rough scale drawings of the two models used in the tests of Requirement 6, and point out the principle design differences.

8. Fly one or more of the Scout's own model planes in competition involving not less than four planes.

9. Measure four flying model planes of Requirement 8 and present Counselor with their comparative flight records and a list of their wing shapes and of their following design rations:

(a) wing span to mean chord;

(b) wing span to propeller diameter;

(c) wing span to fuselage length;

(d) dihedral in inches per foot of span;

(e) wing load in ounces per square inch;

(f) maximum wing camber to chord.

The official source for the information shown in this article or section is: Handbook for Boys, 1948 Edition