Sheet Metal Structural Repairs Flashcards
7 cards from real Airframe Mechanic Certification practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Sheet Metal Structural Repairs flashcards as text
When bending sheet metal, the 'bend allowance' is the amount of material:
Answer: Added to the flat pattern length to account for the curved section
Bend allowance is the additional flat material length that becomes the arc of the bend, added to the flat pattern to get the total blank length.
Springback after bending aluminum sheet is compensated for by:
Answer: Overbending the material slightly beyond the desired angle
Overbending compensates for springback so the sheet returns to the correct angle after the bending force is released.
Which rivet material is required when repairing magnesium alloy aircraft structure to prevent galvanic corrosion?
Answer: Magnesium or aluminum 5056 alloy rivets
5056 aluminum rivets must be used with magnesium structure because they are galvanically compatible; other aluminum or steel rivets cause severe galvanic corrosion.
What condition exists when a rivet exhibits a 'smile' or crescent-shaped crack in the manufactured head after driving?
Answer: The rivet was overdriven (too many hammer blows)
A crescent crack in the rivet head is a sign of overdriving; the excessive deformation stress cracks the head, requiring the rivet to be removed and replaced.
When a structural repair is made to a pressurized fuselage, special attention must be given to:
Answer: Restoring the original pressure-sealing capability using sealant
Pressurized fuselage repairs must restore the original airtight seal using approved sealant to maintain cabin pressurization and structural integrity.
The 'grip length' of a rivet is defined as:
Answer: The thickness of the material being fastened through which the shank passes
Grip length is the total thickness of material being joined, which determines the required rivet length for proper bucktail formation.
When inspecting a completed rivet installation, an acceptable shop head (bucktail) should have a diameter of approximately:
Answer: 1.5 times the rivet diameter and 0.5 times the rivet diameter in height
An acceptable bucktail should be 1.5 times the rivet diameter wide and 0.5 times the rivet diameter tall, indicating a properly driven rivet with full bearing strength.