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What color is aviation gasoline grade 100LL?
Choices
✓ Bluecorrect
100LL (low lead) is dyed blue.
Green
Green is the dye color for grade 100, not 100LL.
Red
Red is the color of the older grade 80.
Clear or straw
Clear or straw indicates turbine jet fuel, which must not be used in a piston engine.
Why
Avgas 100LL is dyed blue, grade 100 is green, and grade 80 is red; turbine jet fuel is clear or straw and must never be used in a piston engine.
FAA source: PHAK Ch. 7browse the reference library →
This is taught in Mixture, Oil and Fuel — study the lessons free, then practice with grading and mastery tracking.
Original study question written for this course — representative of FAA knowledge-test topics, not an actual current FAA exam question.