Aviation Maintenance Technician Series Airframe textbook, Vol. 1 ASA Pages 65–137
Aviation Maintenance Technician Airframe Handbook FAA-H-8083-31 Vol. 1 FAA Chapter 4
Advisory Circular 43.13-1B FAA Pages 4-11–4-51
1. What are three requirements for a repair to a piece of sheet metal aircraft structure?
The repair must restore the lost strength and rigidity, and it must not change the aerodynamic shape of the part.
2. When making a riveted repair to an aircraft sheet metal structure, which should be the stronger, the shear strength of the rivet, or the bearing strength of the metal sheet?
The two strengths should be close to each other, but the bearing strength of the sheet should be the greater.
3. What kind of stress is in the upper skin of an aircraft wing in flight?
Compression.
4. What type of device is a Cleco fastener?
A patented fastener that is inserted in the rivet holes and is used to hold two pieces of sheet metal together until they can be riveted.
5. What is the main function of throatless shears in an aircraft sheet metal shop?
Throatless shears are used to cut mild carbon steel up to 10-gage, and stainless steel up to 12-gage. They can be used to cut irregular curves in the metal.
6. What is the purpose of a sight line when laying out sheet metal to be bent in a cornice brake?
The sight line allows the jaws of a cornice brake to be positioned so the bend made by the brake will start at the bend tangent line.
7. What kind of metal forming is done by a slip roll former?
Simple curves with a large radius.
8. What kind of metal forming is done by bumping?
Compound curves in sheet metal.
9. What must be done to the flanges of an angle for it to be curved?
The flanges must be stretched for a convex curve and shrunk for a concave curve.
10. What is meant by the bend allowance used in making a bend in a piece of sheet metal?
The bend allowance is the amount of metal that is actually used in making the bend in a piece of sheet metal.
11. What determines the minimum bend radius that can be used with a piece of sheet metal?
The thickness of the material and its hardness.
12. What is meant by setback when bending a piece of sheet metal in a cornice brake?
Setback is the distance the jaws of the brake must be set back from the mold line to form the bend.
13. Why are the lightening holes in a sheet metal wing rib flanged?
Flanging the lightening holes gives the rib rigidity.
14. When hand-forming a piece of sheet metal that has a concave curve, should the forming be started in the center of the curve, or at its edges?
Start at the edges and work toward the center.
15. What is meant by a joggle in a piece of sheet metal?
A joggle is a small offset near the edge of a piece of sheet metal that allows the sheet to overlap another piece of metal.
16. When drilling stainless steel, should the drill be turned fast or slow?
It should be turned slowly.
17. What is the minimum edge distance allowed when installing rivets in a piece of aircraft sheet metal structure?
Two times the diameter of the rivet.
18. What is the recommended transverse pitch to use when making a riveted two-row splice in a piece of sheet metal?
Three-fourths of the pitch of the rivets in the rows.
19. Why should aluminum alloy rivets be driven with as few blows as is practical?
Excessive hammering will work-harden the rivets and make them difficult to drive.
20. What determines whether a piece of sheet metal should be dimpled or countersunk when installing flush rivets?
The thickness of the sheet. Countersinking should be done only when the thickness of the sheet is greater than the thickness of the rivet head.
21. What type of metal should be hot-dimpled?
7075-T6, 2024-T81 aluminum alloys, and magnesium alloys should be hot-dimpled.
22. What kind of repair can be made to a small damage of the core material and one face sheet of a piece of aluminum alloy honeycomb structure?
A potted compound repair.
23. What special precautions must be taken when repairing a radome?
Nothing must be done to the radome that will affect its electrical transparency or its aerodynamic strength.
24. How is the point of a twist drill ground that is to be used for drilling transparent acrylic material?
The cutting edge should be dubbed off to a zero rake angle, and the included angle of the tip should be ground to 140 degrees.
25. What causes crazing in a piece of transparent acrylic material?
Uneven stresses in the material, usually caused by heat.
26. What is the purpose of anodizing a piece of aluminum alloy, and how is it applied?
Anodizing is a protective oxide film that is de-posited on the surface of aluminum alloy by an electrolytic process.
1. Lay out and form a channel of specified dimensions from a piece of aluminum alloy sheet. Use the minimum bend radius allowed for the material.
2. Select the correct length and diameter of special rivets furnished by the examiner, and properly install them to join two pieces of aluminum alloy sheet.
3. Make a flush patch repair to a hole in a sheet metal aircraft structure.
4. Select the proper twist drill and demonstrate to the examiner the correct way to drill stainless steel.
5. Select the proper twist drill and demonstrate to the examiner the correct way to drill transparent acrylic plastic.
6. Lay out an octagonal patch that will restore the strength lost by a crack in a piece of stressed fuselage skin.
7. Distinguish between a piece of acrylic plastic and a piece of cellulose acetate plastic.
8. Form a compound curved channel to reinforce a dam-age in a fuselage frame specified by the examiner.
9. Given an assortment of aircraft rivets, identify each by their proper part number and the type of material.
10. Demonstrate to the examiner the correct way to set up and use a squeeze riveter.
11. Properly remove a series of rivets from a piece of aircraft structure.
12. Repair a small damage to a piece of honeycomb structure.
13. Demonstrate to the examiner the correct way to check a bonded honeycomb structure for indication of internal delamination.
14. Repair a shallow scratch in a piece of transparent acrylic material.