What’s So Bad About Vacuum Systems?
You guys produce a great magazine—keep up the good work. But, regarding your December 2015 article about switching to electronic attitude gyros, you act like maintaining a vacuum system is akin to electrics in an old British sports car. Now the FAA is joining the bandwagon of bashing vacuum systems. Vacuum systems are not that bad.
I have flown my Beechcraft Debonair 3900 hours over 20 years in all kinds of weather, including approaches to minimums and in icing and thunderstorms. My vacuum system has never failed. I replace the wet pump every time I replace the engine, which the last time was at 2250 hours. My gyros are reliable, probably because I fly frequently. My vacuum attitude gyro failed once right after I bought the plane probably because the last owner did not fly much. My vacuum directional gyro was replaced once due to excessive precession and will need to be replaced again soon. My RC Allen backup electric attitude gyro also failed once. New vacuum gyros cost $800 new, on average, or $500 for overhauled ones. Electronic attitude gyros cost $5000 to $8000. I’ll keep my vacuum system.