Avionics
Butler National Updates Learjet Standby Instruments
The upgrade will be available to avionics shops for installation in customer Learjets
Mid-Continent Instruments MD-23 aircraft standby attitude indicator
© Mid-Continent Instruments and Avionics

The FAA has issued a supplemental type certificate to Butler National for the installation of Mid-Continent Instruments and Avionics’ replacement two-inch standby altimeter and attitude indicator in Learjet Models 23 through 60.

According to Mid-Continent, the approval allows for the replacement of one or both of the two-inch standby altimeters or two-inch standby attitude indicators installed in most Learjets. The Mid-Continent Digital Attitude Indicator and Counter Drum Encoding Altimeter have liquid-crystal displays and are more reliable than the mechanically-driven instruments they replace.