A reciprocating engine carburetor or intake fire is best extinguished by the use of what type of extinguisher?

The most effective way to extinguish a fire in a reciprocating engine carburetor or intake system is through the use of a CO2 extinguisher. Carbon dioxide (CO2) works by displacing oxygen in the vicinity of the fire, thereby suffocating the flames. This is particularly important for engine fires, as they can be fueled by flammable liquids and vapors found in the fuel system.

Using a CO2 extinguisher also has the advantage of leaving no residue, which is critical in an aircraft where clean-up and potential damage to electrical systems can be a concern. The gaseous nature of CO2 allows it to penetrate the confined spaces of the engine compartment effectively and tackle the fire at its source.

The other types of extinguishers mentioned are less suitable for this type of fire. Water extinguishers can promote steam and may cause flammable liquids to spread, while certain powder extinguishers, although they can work, may leave residues that could harm sensitive aircraft components. Foam extinguishers are primarily effective for liquid fuel fires and may not be as effective in a high-temperature environment like that of an engine fire. Therefore, a CO2 extinguisher is the best option for safely and effectively addressing a carb