Aircraft Wiring Practices and Standards Flashcards
6 cards from real AET practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Aircraft Wiring Practices and Standards flashcards as text
Which wire specification is the current standard for most aircraft applications due to its lightweight PTFE insulation?
Answer: SAE AS22759 / MIL-W-22759 (PTFE-insulated)
SAE AS22759 (formerly MIL-W-22759) uses PTFE (Teflon/Tefzel) insulation, which provides excellent heat resistance, low weight, and durability — making it the current standard for most aircraft wiring applications.
What is the preferred method for splicing aircraft wiring according to FAA Advisory Circular 43.13-1B?
Answer: Approved crimp splices with calibrated crimp tools
Crimp splices using approved tools and correct positioners are the preferred method for aircraft wiring splices. They produce consistent, reliable connections without the risk of cold solder joints or flux contamination associated with soldering.
What is the purpose of using shielded wire in aircraft wiring systems?
Answer: To protect the signal from electromagnetic and radio frequency interference (EMI/RFI)
Shielded wire surrounds the conductor(s) with a conductive braid or foil that is grounded at one end, preventing external EMI/RFI from inducing noise into sensitive signal lines such as audio, sensor, and data bus wiring.
According to aircraft wiring standards, what is the minimum bend radius typically required when routing a wire bundle to prevent insulation damage?
Answer: Three times the outside diameter of the wire bundle
AC 43.13-1B specifies that wire bundles should not be bent to a radius less than three times the outside diameter of the bundle. Tighter bends stress the insulation and conductors, potentially causing cracks or breaks.
When terminating aircraft wiring with a circular MS-series (MIL-DTL-38999) connector, what is the most critical requirement for the crimping operation?
Answer: Use the correct approved positioner and die set matched to the specific contact size and wire gauge
Approved crimp tool positioners and dies are engineered to produce the precise crimp geometry (height and width) required for each specific contact size and wire gauge combination. Using incorrect tooling will produce a non-conforming crimp that can fail in service.
On an aircraft wiring diagram, a wire labeled '20AWG' indicates what about the conductor?
Answer: The conductor size is American Wire Gauge 20, indicating its cross-sectional diameter
AWG (American Wire Gauge) is a standardized system for wire conductor sizing. A higher AWG number means a smaller conductor diameter. 20AWG is a common gauge for aircraft signal and low-current power wiring.