The FAA has issued a supplemental type certificate (STC) to Butler National subsidiary Avcon Industries and its affiliate Butler Avionics to replace portable Halon fire extinguishers with non-Halon units for all Learjets from the Model 24 through the Learjet 75.
Replacement portable extinguishers, manufactured by Amerex, use Halotron BrX, and they are size-equivalent, “having minimal impact on fit and compatibility,” according to Avcon.
While Halon is still allowed to be used for aircraft fire extinguishers, its manufacture has been prohibited since 1994 because it is an ozone-depleting substance. Recycled Halon is used to recharge portable aircraft fire extinguishers, aircraft cargo compartment fire extinguishing systems, and fuel inerting systems, but supplies of Halon eventually will be exhausted.
Though the U.S. still allows Halon fire extinguishers in aircraft, EASA has ruled that Halon portable aircraft fire extinguishers be replaced by Dec. 31, 2025, and other systems by 2040. This rule does not apply to non-EU-registered aircraft, according to NBAA.
Avcon is applying for EASA validation of the Learjet STC and plans to add other aircraft models to the STC’s approved model list.