FAA Aviation Mechanic Powerplant (AMP)Fuel, Induction and LubricationEasy
A line technician is servicing a piston-powered aircraft and must select the correct fuel. The aircraft fuel filler placard specifies 100LL. What color should this fuel be, and what does this help prevent?
- AClear; helps prevent confusion with automotive gasoline, which is yellow
- BGreen; helps prevent contamination with 80/87 fuel, which is red
- CBlue; helps prevent misfueling with Jet A, which is clear or straw colored
- DPurple; helps prevent confusion with 100/130 fuel, which is green
Show answer & explanationAnswer & explanation
Correct answer: C. Blue; helps prevent misfueling with Jet A, which is clear or straw colored
100LL (low lead) aviation gasoline is dyed blue, while turbine fuel (Jet A/Jet A-1) is clear to straw colored. Color coding helps line personnel visually verify they are dispensing the correct fuel type and avoid dangerous misfueling.
Why the other options are wrong
- A. 100LL is not clear; automotive gasoline color is irrelevant to this aviation fuel comparison.
- B. 80/87 avgas (now obsolete) was red, not part of the 100LL comparison being asked.
- D. 100/130 avgas (green) is a discontinued grade, not the relevant comparison here.
Aviation Fuel Color Coding
Aviation gasoline grades are dyed different colors to allow quick visual identification and prevent misfueling.
- 100LL avgas = blue
- Jet A/A-1 = clear to straw colored
- Color coding is a critical safety check before fueling
- Misfueling a piston engine with jet fuel can cause catastrophic failure
Memory trick: Blue Bird flies on 100LL, Jet flies clear as glass