REVUE THOMMEN reported that Bombardier selected their AD20 two inch Electronic Standby Altimeter as a retrofit option for the fleet of Bombardier Challenger 601-3A/3R and 604 aircraft. The AD20 is the first electronic standby altimeter in the industry per RTCA DO-178B designed with software level A required for installation in a Part 25 jet aircraft.
After careful review of the various options available on the market, Bombardier selected the THOMMEN AD20 in order to offer customers enhanced features not available with mechanical standby altimeters, as well as improved reliability. This improvement is part of Bombardier’s on-going engagement to enhance its out-of-production aircraft.
The THOMMEN AD20 standby altimeter provides both a dedicated digital liquid crystal display (LCD) and an analog pointer, and features high intensity backlighting for daylight conditions. The altitude can be displayed in both lmperial Format ( inHg-ft or hPa- ft) as well as Metric Format ( hPa- m) and it also allows operation at lower barometric settings (20.67 inHg). The extensive Built-ln-Test (BlT) ensures normal operation with each power on.
