Airframe Flashcards
How do you determine the total length of a solid rivet for installation?
The grip length +1.5 X the rivet diameter
Give examples self plugging, mechanical lock rivets
- Cherrylock
- Cherrymax
- Hulklock
- Olympiclock
- CherrySST
What is done with the rivet head stem when a self plugging rivet is install installed?
The stem is pulled until it snaps off, and any remaining projecting part is trimmed flush with the head
What power sources are normally used to retract landing gear systems?
Hydraulic or electrical
What methods are used in forming sheet metal?
- Shrinking.
- Stretching
- Bumping
- Crimping
- Folding
What factors are used to determine setback?
Bend radius and material thickness
What calculation must be made when bending sheet metal?
Bend allowance and setback
What must be done when two bands intersect to prevent cracking?
Relief holes are drilled at the intersection or corner
What is a joggle?
An offset formed on a part to allow clearance for a sheet or another mating part
What is the purpose of lightning holes cut in rib sections?
To reduce weight and increase off stiffness
Describe rivet head markings for A, B, D, AD and DD rivets
A rivets – plain, no marks
B rivets – have a cross
D rivets – have a raised dot
AD rivets – have a dimple
DD rivets – have a double dash
What are the correct dimensions on a properly formed rivet head?
Shop head should have a diameter of one and 1 1/2 times the original rivet diameter and its depth should at least be 1/2 the rivet diameter
How do you determine the proper material to be used for a repair on an all metal aircraft?
Use the same type and thickness of material that was used in the original structure
What is the single row spacing and edge distance for protruding head rivets?
Edge is 2 times the diameter
Spacing is 3 times the diameter
Describe the criteria for replacement of a 2024 rivet with a 2117 rivet for general repairs
For 2024 rivets 5/32 or less diameter use the next larger size 2117 rivet using the minimum requirements for edge and spacing distance
What is the major type of damage to aluminum structures that is caused by exposure to weather?
Corrosion
What is the difference between the tools required to pull a cherry lock rivet and a cherry max rivet?
Cherry lock – require a different tool for each rivet size
Cherry max – same tool for all
How can a mechanic determine whether the counter sink for a flush rivet should be dimple or drilled?
By the thickness of the top sheet, thin sheets are dimple and thick sheets may be countersunk
What action is taken to prevent cracks from forming while dimpling, magnesium or some hard sheet metals?
Hot dimpling equipment is used to preheat and soften the metal before the dimple is formed
What type of damage can occur when using a rivet set that does not properly fit the rivet?
The rivet head and the sheet metal may be damaged
Why is it important to use the proper bucking bar when performing sheet metal riveting?
Bucking bar, too large or heavy— difficult to control and you can damage the sheet metal
Bucking bar too light — Will not properly set the rivet before work Hardening occur.
What procedures should be followed to properly remove a solid shank rivet?
Center punched the rivet and drilled to the base of the rivet head using the same size or one size smaller drill, then use a pin punch to break off the rivet head
Which of the five stresses is the most common cause of rivet failure?
Shear
In accordance with 14 CFR 65.85 and 65.87 what type of inspection may a certified airframe and power plant mechanic sign off?
100 hour inspection