Aviation fuel identification, fueling safety and fire classes
Ground operations questions favor the rules that prevent the worst accidents on a ramp: putting the wrong fuel in an engine, a static spark at the filler neck, and the wrong extinguisher on a burning magnesium wheel.
| AVGAS colors | 80 red; 100 green; 100LL blue; 115 purple |
| Jet fuel | Marked black on piping; the fuel itself is clear to straw colored |
| Grounding order | Aircraft, then truck, bond them, then nozzle to aircraft before opening the tank |
| Never ground to | The propeller |
| Ground radar | Do not fuel within 500 feet of operating ground radar |
| Class A / B / C | Ordinary combustibles / flammable liquids / energized electrical |
| Class D | Burning metal; never water or CO2 |
| Engine start fireguard | CO2 extinguisher of at least 5-pound capacity |
Where the point is lost: The fuel color question is easy to lose by mixing up 100 (green) and 100LL (blue). Learn them as a pair.
Aviation fuel identification, fueling safety and fire classes
8 questions on aviation fuel colors and fire classes, each with an explanation and statute citation.
8 questions
Pass line: 70%, same as the real exam
Questions and answers, explained
All 8 questions above, with the correct answer and why it is correct. Everything here is on aviation fuel identification, fueling safety and fire classes.
A fire involving spilled jet fuel and hydraulic fluid on the hangar floor is classified as
Why: Class B fires involve flammable petroleum products and other flammable liquids, greases, solvents and paints. Class A is ordinary combustibles, Class C is energized electrical equipment, and Class D is flammable metal.
Reference AM.I.F.K6 · FAA-H-8083-30B, Ch. 1 (Classification of Fires)
A magnesium wheel catches fire after a hard braking event. Which extinguishing agents must NOT be used on it?
Why: Burning magnesium is a Class D fire. The handbook says never use water or CO2 on Class D fires: their cooling effect on the extremely hot metal can cause explosive expansion. Use a dry powder agent intended for metal fires.
Reference AM.I.F.K6 · FAA-H-8083-30B, Ch. 1 (Types and Operation of Shop and Flight Line Fire Extinguishers)
Why must extreme caution be used when discharging a CO2 extinguisher in a closed or confined area?
Why: CO2 smothers a fire by displacing oxygen, and the handbook warns that in a closed space it can deprive the operator of oxygen as well. The extinguisher also gets extremely cold, so protection against frostbite is needed.
Reference AM.I.F.K6 · FAA-H-8083-30B, Ch. 1 (Carbon Dioxide Extinguishers)
Grade 100LL aviation gasoline is identified by which color?
Why: The handbook's AVGAS color code: 80 is red, 100 is green, 100LL is blue and 115 is purple. The fuel's color should match the color band on the piping and fueling equipment.
Reference AM.I.F.K9 · FAA-H-8083-30B, Ch. 1 (Figure 1-31, Aviation Gasoline Color and Grade Reference)
How is jet fuel identified on piping and fueling equipment?
Why: The handbook: jet fuel is identified by the color black on piping and fueling equipment, while the fuel itself is clear or straw colored. Jet A and Jet A-1 are kerosene; Jet B is a blend of kerosene and AVGAS.
Reference AM.I.F.K9 · FAA-H-8083-30B, Ch. 1 (Fuel Servicing of Aircraft)
When refueling from a fuel truck, in what order are the static grounds made?
Why: The handbook's sequence: ground the aircraft, then the truck, then bond them together, then ground the nozzle to the aircraft before opening the fuel tank. Grounds go on bare metal, and never on the propeller, which has no positive bond to the airframe.
Reference AM.I.F.K3 · FAA-H-8083-30B, Ch. 1 (Procedures for Fueling)
Per the FAA handbook, an aircraft should not be fueled within what distance of operating ground radar?
Why: The handbook's fueling precautions include not fueling an aircraft within 500 feet of operating ground radar, whose energy can ignite fuel vapors.
Reference AM.I.F.K3 · FAA-H-8083-30B, Ch. 1 (Procedures for Fueling)
During any engine start, the handbook calls for a fireguard to be standing by with
Why: A fireguard familiar with the starting procedure stands by with a CO2 extinguisher of at least 5-pound capacity, positioned beside the outboard side of the engine in view of the operator, ready to direct CO2 into the intake in case of an induction fire.
Reference AM.I.F.K5 · FAA-H-8083-30B, Ch. 1 (Starting Engines)
Drill the whole domain
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