Questions - Aircraft Metal Structure Repair

Study Aid Questions

Fill in the Blanks

1. A joint that is too weak cannot be tolerated, but neither can one that is too ______ because it can create stress risers that may cause ______ in other locations.

2. There are six types of stresses: tension, compression, ______, and bearing are known as basic stresses; while bending and ______ (or twisting) are considered combination stresses.

3. There are two ways to determine rivet size: (1) the size of rivets in the next ______ rivet row inboard on the wing and (2) multiple the thickness of the thickest sheet by ______ and use the next larger size.

4. Aircraft structural joint design involves an attempt to find the optimum strength relationship between being critical in ______ and critical in ______.

5. A file with a single row of ______ teeth is called a single‐cut file; whereas files with one row of teeth crossing under another row are called files ______.

6. Files are classified according to their ______. The most common files include: flat, triangle, square, ______, and round.

7. ______ drill motors are recommended for use on projects around flammable materials where potentials spark from a(n) ______ drill motor might become a fire hazard.

8. Properly adjusted drill ______ can prevent excessive drill penetration that might damage the ______ structure or injure personnel.

9. A bar folder is designed for use in making ______ or folds along edges of sheet metal.

10. ______ breaks are used to form thicker more ______ parts.

11. On the slip roll, the front rollers ______ or grip the metal sheet while the rear roll provides the proper ______ to the work.

12. It is advantageous to ______ or even polish the edges of a flange that must undergo even moderate ______ to avoid crack formation.

13. ______ made of hardwood are widely used in airframe metalwork for shrinking and stretching metal, particularly angles and ______.

14. The minimum bend radius is affected by; the kind of material, ______ of the material, and ______ condition of the material.

15. The ______ must be used for all bend that are smaller or larger than ______.

16. In order to form a box, it is necessary to drill ______ at the intersection of the inside bend ______ lines.

17. Machining characteristics of magnesium are ______, making possible the use of maximum speeds of the machine tools with heavy cuts and high ______ rates.

18. Rivets fill the hole during the installation process which provides a good ______ transfer.

19. Blind rivets are installed during ______ where access is not available to form the driven head of ______ rivets.

20. The CherryMax rivet consists of five parts; ______ blind header, hollow rivet shell, ______ collar, driving anvil, and the pulling stem.

21. Collars used with Hi‐Lok fasteners have a ______ break‐off groove which shears off at a predetermined ______, leaving the lower portion of the collar seated with the proper torque.

22. An interference fit is typically used for ______ and ______ fit is used for steel, titanium, and composites.

23. Rivnuts are internally threaded ______ that have a flush or shallow ______ heads.

24. Rivet diameter should not be ______ than 3 times the thickness of the ______ sheet.

25. Rivet ______ is the distance between the centers of ______ rivets in the same row.

26. If countersinking is done on metal below a certain thickness a ______ with less than minimum bearing surface or ______ of the hole may occur.

27. A rivet gun with the correct header must be held snugly against the head and ______ to the surface while the bucking bar of the proper ______ is held against the opposite end.

28. ______ repair is very important because of the load it carries and particular care should be taken to ensure the original ______ of the structure is not impaired.

29. A scale or ______ can be used to check the condition of the upset rivet head to see that it conforms to the proper requirements.

30. ______ dimpling is the process that uses heated dimpling dies so that the material will ______ better during the dimpling process.

True or False

1. The top of a wing spar, in flight, is subjected to a compressive stress. TRUE/FALSE

2. The bottom of a wing spar, in flight, is subjected to a compressive stress. TRUE/FALSE

3. If a properly designed rivet joint fails, the rivet first will pull out of the metal. TRUE/FALSE

4. Aircraft structures are most likely to fail at points where stresses concentrate due to abrupt changes in cross-sectional area. TRUE/FALSE

5. To prevent a small crack from extending, you may not stop-drill its end. TRUE/FALSE

6. Aluminum alloys are not susceptible to corrosion. TRUE/FALSE

7. Alclad is pure aluminum that is rolled onto the surface of heat-treated aluminum alloys. TRUE/FALSE

8. When an aluminum alloy is heated to its critical temperature and quenched, it is precipitation heat treated. TRUE/FALSE

9. Artificial aging is another name for precipitation heat-treatment. TRUE/FALSE

10. Aluminum alloys may be softened by annealing. TRUE/FALSE

11. Magnesium is heavier than aluminum. TRUE/FALSE

12. Pure aluminum will not corrode. TRUE/FALSE

13. When using a scale for sheet metal layout, you should measure from its end. TRUE/FALSE

14. Scribes should be used to mark bend lines because the part will crack when it is bent. TRUE/FALSE

15. Felt marking pens are widely used for sheet metal layout. TRUE/FALSE

Matching Questions

1 ‐ Matching (answers may be used more than once)

a. Tension   b. Compression   c. Shear   d. Bearing   e. Torsion   f. Bending{codeBox}

____  1. The force that resists the force that rivets or bolts place 
____  2. The force per unit area which causes adjacent particles of material to slide past each other.
____  3. A combination of two forces acting upon a structural member at one or more points. 
____  4. The force which tends to twist a structural member. 
____  5. The force per unit area which tends to stretch a structural member. 
____  6. The force per unit area which tends to shorten a structural member at any cross section. 






2 ‐ Matching

a. Brinelling   b. Burnishing   c. Burr   d. Corrosion   e. Crack   f. Cut   g. Dent   h. Erosion   i. Chattering   j. Galling   k. Gouge   l. Inclusion   m. Nick   n. Pitting   o. Scratch   p. Score   q. Stain   r. Upsetting{codeBox}

____  1. Presence of foreign or extraneous material wholly within a portion of metal
____  2. A small, thin section of metal extending beyond a regular surface
____  3. Breakdown or deterioration of metal surface by vibratory action
____  4. A change in color, locally causing a noticeably different appearance
____  5. Loss of metal, usually to an appreciable depth over a relatively long, narrow area
____  6. Occurrence of shallow, spherical depressions in a surface
____  7. A physical separation of two adjacent portions of metal
____  8. Slight tear or break in metal surface from light contact by a foreign object
____  9. Indentation in a metal surface produced by an object striking with force
____  10. Loss of metal from the surface by chemical or electrochemical action
____  11. Deep tear or break in metal surface from contact under pressure
____  12. Breakdown of metal surfaces due to excessive friction between two part
____  13. Local break or notch on edge
____  14. A displacement of material beyond the normal contour or surface
____  15. Polishing of one surface by sliding contact with a smooth, hard surface
____  16. Loss of metal from the surface by mechanical action of foreign object
____  17. Sharp, localized breakdown of metal surface with defined edges
____  18. Grooves in a metal surface from contact with foreign material under heavy pressure

3 ‐ Matching

a. scales   b. combination square   c. dividers   d. rivet spacer   e. marking tool   f. scribes   g. punches   h. awls   i. hole duplicator{codeBox}

____  1. Makes quick and accurate rivet pattern lay‐outs on a sheet
____  2. Only used when marks will be removed by drilling or cuttinge
____  3. A scale with three heads that can be moved to any position on the scale
____  4. A carbon steel tempered marking tool
____  5. Comes in lengths most commonly 6” and 12”
____  6. Used to locate and match existing holes in structures
____  7. Fiber tipped pen
____  8. Used in aircraft maintenance to align holes
____  9. Transfer measurement from a device to a scale to determine its value

4 ‐ Matching

a. prick punch  b. center punch  c. automatic center punch   d. transfer punch   e. pin punch   f. drive punch   g. chassis punch{codeBox}

____  1. Has an adjustable cap for regulating the stroke
____  2. Used to transfer dimensions from a paper pattern directly onto metal
____  3. Also known as a drift punch
____  4. Used to mark the locations of new holes using a template or existing holes
____  5. Used to make holes in sheet metal
____  6. Used to make large indentations in metal for a twist drill
____  7. Used to drive out damaged rivets, pins and bolts

5 ‐ Matching

1. Body               2. Land               3. Cutting Lips               
4. Notched Point Chisel Edges               5. Flute               6. Shank               

6 ‐ Matching

a. leg   b. flange   c. grain of metal   d. bend radius   e. neutral axis   f. mold line   g. mold point   h. bend tangent line   i. setback   j. flat   k. bend allowance   l. bend line   m. closed angle   n. open angle   o. K factor   p. total developed{codeBox}

____  1. Located where the metal starts to bend and the metal stops curving
____  2. Set even with the nose of the brake and acts as a guide for bending
____  3. Measured from a radius center to the inside surface of the metal
____  4. Width of material, measured around the bends from edge to edge
____  5. The distance from the mold point to the bend tangent line
____  6. angle that is more than 90° when measured between legs
____  7. Line formed by extending the outside surface of the leg and flange to a point in space
____  8. The longer part of a formed angle
____  9. The curved section of metal within the bend
____  10. The shorter part of a formed angle
____  11. Corresponds to one of the angles to which metal can be bent
____  12. An imaginary line that has the same length after bending as it had before
____  13. The base measurement minus setback (=MLD‐SB)
____  14. The point of intersection of the mold lines
____  15. Angle that is more than 90° when the amount of bend is measured
____  16. Bend should preferably be made to lie at an angle to this width

Knowledge Application Questions

1. What are three requirements for a repair to a piece of sheet metal aircraft structure?

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?

3. What type of device is a Cleco fastener?

4. What is the main function of throatless shears in an aircraft sheet metal shop?

5. What is the purpose of a sight line when laying out sheet metal to be bent in a cornice brake?

6. What kind of metal forming is done by a slip roll former?

7. What kind of metal forming is done by bumping?

8. What must be done to the flanges of an angle for it to be curved?

9. What is meant by the bend allowance used in making a bend in a piece of sheet metal?

10. What determines the minimum bend radius that can be used with a piece of sheet metal?

11. What is meant by setback when bending a piece of sheet metal in a cornice brake?

12. What factors must be considered in order to determine setback?

13. Why are the lightening holes in a sheet metal wing rib flanged?

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?

15. What is meant by a joggle in a piece of sheet metal?

Multiple Choices Questions

1. A well designed rivet joint will subject the rivets to
a. compressive loads.
b. tension loads.
c. shear loads.

2. A main difference between Lockbolt/ Huckbolt tension and shear fasteners (other than their application) is in the
a. method of installation.
b. number of locking collar grooves.
c. shape of the head.

3. Alloy 2117 rivets are heat treated
a. to a temperature of 910 to 930 OF and quenched in cold water.
b. by the manufacturer and do not require heat treatment before being driven.
c. by the manufacturer but require reheat treatment before being driven.

4. The general rule for finding the proper rivet diameter is
a. three times the thickness of the thickest sheet.
b. two times the rivet length.
c. three times the thickness of the materials to be joined.

5. The shop head of a rivet should be
a. one and one-half times the diameter of the rivet shank.
b. one and one-half times the diameter of the manufactured head of the rivet.
c. one-half times the diameter of the rivet shank.

6. One of the main advantages of Hi-Lok type fasteners over earlier generations is that
a. the squeezed on collar installation provides a more secure, tighter fit.
b. they can be removed and reused again.
c. they can be installed with ordinary hand tools.

7. The markings on the head of a Dzus fastener identify the
a. manufacturer and type of material.
b. body type, head diameter, and type of material.
c. body diameter, type of head, and length of the fastener.

8. The Dzus turnlock fastener consists of a stud, grommet, and receptacle. The stud length is measured in
a. sixteenths of an inch.
b. tenths of an inch.
c. hundredths of an inch.

9. The Dzus turnlock fastener consists of a stud, grommet, and receptacle. The stud diameter is measured in
a. sixteenths of an inch.
b. hundredths of an inch.
c. tenths of an inch.

10. Threaded rivets (Rivnuts) are commonly used to
a. join two or more pieces of sheet metal where shear strength is desired.
b. join two or more pieces of sheet metal where bearing strength is desired.
c. attach parts or components with screws to sheet metal.

11. Cherrymax and Olympic-Lok rivets
a. may be installed with ordinary hand tools.
b. utilize a pulling tool for installation.
c. utilize a rivet gun, special rivet set, and bucking bar for installation.

12. Hole filling fasteners (for example, MS20470 rivets) should not be used in composite structures primarily because of the
a. possibility of causing delamination.
b. difficulty in forming a proper shop head.
c. increased possibility of fretting corrosion in the fastener.

13. Metal fasteners used with carbon/graphite composite structures
a. must be constructed of high strength aluminum-lithium alloy.
b. must be constructed of material such as titanium or corrosion resistant steel.
c. may be constructed of any of the metals commonly used in aircraft fasteners.

14. If a new safety belt is to be installed in an aircraft, the belt must conform to the strength requirements in which document?
a. TSO C22.
b. FAR Part 39.
c. STC 1282.

15. Select the alternative which best describes the function of the flute section of a twist drill.
a. Forms the cutting edges of the drill point.
b. Forms the area where the drill bit attaches to the drill motor.
c. Prevents overheating of the drill point.

16. How many MS20470 AD-4-6 rivets will be required to attach a 10" x 5" plate, using a single row of rivets, minimum edge distance, and 4D spacing?
a. 54
b. 56
c. 52

17. Shallow scratches in sheet metal may be repaired by
a. buffing.
b. burnishing.
c. stop drilling.

18. What should be the included angle of a twist drill for soft metals?
a. 1180
b. 900
c. 650

19. When comparing the machining techniques for stainless steel sheet material to those for aluminum alloy sheet, it is normally considered good practice to drill the stainless steel at a
a. higher speed with less pressure applied to the drill.
b. lower speed with less pressure applied to the drill.
c. lower speed with more pressure applied to the drill.

20. A single lap sheet splice is to be used to repair a section of damaged aluminum skin. If a double row of 118-inch rivets is used, the minimum allowable overlap will be
a. 3/4 inch.
b. 13/16 inch.
c. 1/2 inch.

21. Which statement is true regarding the inspection of a stressed skin metal wing assembly known to have been critically loaded?
a. If rivets show no visible distortion, further investigation is unnecessary.
b. If genuine rivet tipping has occurred, groups of consecutive rivet heads will be tipped in the same direction.
c. If bearing failure has occurred, the rivet shanks will be joggled.

22. What is the minimum edge distance for aircraft rivets?
a. Three times the diameter of the rivet shank.
b. Two times the diameter of the rivet head.
c. Two times the diameter of the rivet shank.

23. When drilling stainless steel, the drill used should have an included angle of
a. 140" and turn at a low speed.
b. 118" and turn at a high speed.
c. 90" and turn at a low speed.

24. What is the minimum spacing for a single row of aircraft rivets?
a. Three times the length of the rivet shank.
b. Three times the diameter of the rivet shank.
c. Two times the diameter of the rivet shank.

25. (Refer to figure 1.) Which of the rivets shown will accurately fit the conical depression made by a 100" countersink?
a. 3
b. 2
c. 1

Figure 1. Rivets

26. Which is correct concerning the use of a file?
a. A smoother finish can be obtained by using a double cut file than by using a single cut file.
b. Apply pressure on the forward stroke, only, except when filing very soft metals such as lead or aluminum.
c. The terms "double cut" and "second cut" have the same meaning in reference to files.

27. What is one of the determining factors which permits machine countersinking when flush riveting?
a. Thickness of the material and rivet diameter are the same.
b. Thickness of the material is greater than the thickness of the rivet head.
c. Thickness of the material is less than the thickness of the rivet head.

28. When repairing a small hole on a metal stressed skin, the major consideration in the design of the patch should be
a. that the bond between the patch and the skin is sufficient to prevent dissimilar metal corrosion.
b. the shear strength of the riveted joint.
c. to use rivet spacing similar to a seam in the skin.

29. Which procedure is correct when using a reamer to finish a drilled hole to the correct size?
a. Turn the reamer only in the cutting direction.
b. Apply considerable pressure on the reamer when starting the cut and reduce the pressure when finishing the cut.
c. Turn the reamer in the cutting direction when enlarging the hole and in the opposite direction to remove from the hole.

30. Repairs or splices involving stringers on the lower surface of stressed skin metal wings are usually
a. permitted only if the damage does not exceed 6 inches in any direction.
b. not permitted.
c. permitted but are normally more critical in reference to strength in tension than similar repairs to the upper surface.

31. When straightening members made of 2024-T4, you should
a. straighten cold and anneal to remove stress.
b. straighten cold and reinforce.
c. apply heat to the inside of the bend.

32. Clad aluminum alloys are used in aircraft because they
a. are stronger than unclad aluminum alloys.
b. are less subject to corrosion than uncoated aluminum alloys.
c. can be heat treated much easier than the other forms of aluminum.

33. Aircraft structural units, such as spars, engine supports, etc., which have been built up from sheet metal, are normally
a. repairable, using approved methods.
b. not repairable, but must be replaced when damaged or deteriorated.
c. repairable, except when subjected to compressive loads.

34. A factor which determines the minimum space between rivets is the
a. diameter of the rivets being used.
b. length of the rivets being used.
c. thickness of the material being riveted.

35. What should be the included angle of a twist drill for hard metal?
a. 1180
b. 900
c. 1000

36. When fabricating parts from Alclad 2024-T3 aluminum sheet stock,
a. bends should be made with a small radius to develop maximum strength.
b. all bends must be 90" to the grain.
c. all scratches, kinks, tool marks, nicks, etc., must be held to a minimum.

37. Rivet gauge, or transverse pitch is the distance between the
a. heads of rivets in the same row.
b. centers of rivets in adjacent rows.
c. centers of adjacent rivets in the same row.

38. Rivet pitch is the distance between the
a. centers of adjacent rivets in the same row.
b. heads of rivets in the same row.
c. centers of rivets in adjacent rows.

Figure 2. Countersinking

40. (Refer to figure 2.) Select the preferred drawing for proper countersinking.
a. 2.
b. 1.
c. All are acceptable.

FAA airframe test questions with answers
Download fillable PDF

For more questions go to the Aeronautics Guide Patreon page. Becoming a Patreon, you can explore more questions and can download them. For more details see Question Paper post.{alertInfo}

Previous Post Next Post