Avcon Industries and affiliate Butler Avionics, subsidiaries of Butler National Corporation, received FAA STC approval for the installation of non-halon portable fire extinguisher replacements in Learjet 24, 25, 29, 31, 31A, 35, 36, 35A (C-21A), 36A, 40, 45, 55, 55B, 55C, 60, 60XR, 70 and 75 model aircraft.

The company received STC No. ST12087CH, covering the replacement of halon fire extinguishers with Halotron BrX-filled extinguishers. These are designed for straightforward retrofit and compliance with European Union Aviation Safety Agency requirements. An application has been made for EASA validation.

Halon has been classed as an ozone-depleting substance. Its production was banned in the EU in 1994, although certain aircraft systems were given exemptions. Regulations now require cabin and crew compartment halon extinguishers to be replaced by 31 December 2025.

“Avcon and Butler Avionics teamed with a leading specialty fire extinguisher vendor to make available non-halon fire extinguishers to comply with the pending EASA mandate and obtain STC installation approval for Learjets,” says Patrick Hupp, avionics manager. “The new extinguishers are engineered for straightforward installation in the same location as existing units, with provisions for additional mounting locations in some legacy Learjet models. We are working diligently to obtain EASA approval for the replacement fire extinguisher installation. Avcon and Butler Avionics are also working to add additional models to the STC-approved model list. Avcon and Butler continue their commitment to supporting legacy aircraft with cost-effective regulatory solutions.”