Troubleshooting Techniques & Inspection Standards Flashcards
7 cards from real ACS practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Troubleshooting Techniques & Inspection Standards flashcards as text
An aircraft engine has a magneto drop of 175 RPM on one magneto and 50 RPM on the other during run-up. The maximum allowable drop is 125 RPM. What does this indicate?
Answer: The magneto showing 175 RPM drop has an ignition problem requiring investigation
A magneto drop exceeding the maximum allowable limit (175 RPM vs. 125 RPM limit) indicates a faulty ignition component such as spark plugs, ignition leads, or the magneto itself.
During an eddy current inspection of an aluminum wing spar, a large meter deflection is noted at a specific location. This most likely indicates:
Answer: A crack, corrosion, or other discontinuity at that location requiring further evaluation
Eddy current meter deflections indicate changes in conductivity or permeability caused by cracks, corrosion, or thickness variations requiring further investigation.
An aircraft exhaust system inspection reveals blue discoloration on the exhaust stack. This is significant because it may indicate:
Answer: Engine oil leaking into the exhaust or extreme overheating of the exhaust system
Blue discoloration on exhaust components can indicate oil contamination in the exhaust stream or localized overheating, both of which require investigation for engine health.
When inspecting aircraft tires for continued airworthiness, what condition mandates immediate removal from service?
Answer: Fabric cord showing through the tread
Exposed fabric cords in aircraft tires represent a critical safety hazard requiring immediate removal from service regardless of remaining tread depth.
A mechanic is troubleshooting an aircraft electrical system where the ammeter shows a continuous discharge. The most likely cause is:
Answer: A failed alternator or generator not supplying charging current
A continuous ammeter discharge reading indicates the alternator or generator is not producing current and the battery is supplying all electrical loads.
During a 100-hour inspection, you discover a propeller blade with a nick 1/8 inch deep and 3/4 inch long on the leading edge. What is required?
Answer: Dress out the nick per the manufacturer's limits and check if it falls within serviceable limits
Propeller nicks must be evaluated against the manufacturer's damage limits; if within limits, they can be dressed out using approved methods, and the repair must be documented.
An aircraft fuel-injected engine that runs rough at cruise power but smoothly at full throttle most likely has:
Answer: A partially blocked fuel injector nozzle causing a lean condition at cruise
A partially blocked injector creates a lean mixture in one cylinder that is more pronounced at cruise power settings where fuel flow is lower, causing rough running.