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The short answer is NO! The The best answer is to cite NFPA Standards and other published documents:
NFPA 410 Aircraft Maintenance (Addendum) A-7-3.1
All-purpose (ABC) dry chemical-type extinguishers should not be used in situations where aluminum corrosion is a problem.
NFPA Fire Protection Handbook Chapter-Basics of Fire and Science
Extinguishment with Dry Chemical Agents:
One reason that dry chemical agents other than monoammonium phosphate are popular has to do with corrosion. Any chemical powder can produce some degree of corrosion or other damage, but monoammonium phosphate is acidic and corrodes more readily than other dry chemicals, which are neutral or mildly alkaline. Furthermore, corrosion by other dry chemicals is stopped by moderately dry atmosphere, while phosphoric acid has such a strong affinity for water that an exceedingly dry atmosphere would be needed to stop corrosion.
Air Transport Newsletter, by Ronald Horn, Nov./Dec. 1983, "Class A-B-C Extinguishers Damage Aircraft."
"The A-B-C extinguishers have excellent fire-fighting capability, but the mono-ammonium-phosphate chemical agent melts and flows when it comes into contact with heat. This is how it gets its Class A rating. This chemical is highly corrosive to aluminum, and once it contacts hot aluminum and flows down into the structural cracks and crevices it cannot be washed out as the B-C dry chemical agents can."
"Once an A-B-C extinguisher is used on an airplane, it is necessary to disassemble the aircraft piece by piece and rivet by rivet to accomplish cleanup. Failure to do so will result in destruction of the aircraft by corrosion."
NFPA 410 Aircraft Maintenance (Addendum) A-7-3.1
All-purpose (ABC) dry chemical-type extinguishers should not be used in situations where aluminum corrosion is a problem.
NFPA Fire Protection Handbook Chapter-Basics of Fire and Science
Extinguishment with Dry Chemical Agents:
One reason that dry chemical agents other than monoammonium phosphate are popular has to do with corrosion. Any chemical powder can produce some degree of corrosion or other damage, but monoammonium phosphate is acidic and corrodes more readily than other dry chemicals, which are neutral or mildly alkaline. Furthermore, corrosion by other dry chemicals is stopped by moderately dry atmosphere, while phosphoric acid has such a strong affinity for water that an exceedingly dry atmosphere would be needed to stop corrosion.
Air Transport Newsletter, by Ronald Horn, Nov./Dec. 1983, "Class A-B-C Extinguishers Damage Aircraft."
"The A-B-C extinguishers have excellent fire-fighting capability, but the mono-ammonium-phosphate chemical agent melts and flows when it comes into contact with heat. This is how it gets its Class A rating. This chemical is highly corrosive to aluminum, and once it contacts hot aluminum and flows down into the structural cracks and crevices it cannot be washed out as the B-C dry chemical agents can."
"Once an A-B-C extinguisher is used on an airplane, it is necessary to disassemble the aircraft piece by piece and rivet by rivet to accomplish cleanup. Failure to do so will result in destruction of the aircraft by corrosion."
