How long should my gyro last?
There are many factors that determine the life of a gyro. If a gyro sits stationary for a long period of time the bearings become unusable. If your vacuum hoses and filters are not replaced periodically the carbon dust from your vacuum pump can end up in your gyro. We have seen gyros with everything from corrosion from sea air to excessive bearing wear from rough landings. Ideally you should receive hundreds of hours of use, but it is completely dependent on how the unit is treated and the environment in which it is used.

How much vacuum is needed for my gyro to run properly?
The rotor in your R.C. Allen gyro will start to spin at 2.5 in Hg, and will become fully functional at 4.5 in Hg. It requires approximately 3 minutes of run time to accomplish full run up of the gyro.

Should my vacuum gyro shake when powered up?
During the 3 minutes it takes for the gyro to “run up” you might see the instrument “shake” this is normal and will stop when the rotor reaches full speed. This does not mean your instrument is defective.

At what voltage level will my electric gyro become unreliable?
● For a 14VDC system a minimum of 12VDC is required for the unit to operate accurately.
● For a 28VDC system a minimum of 26.5VDC is required for the unit to operate accurately.
Our RCA26EK and RCA15EK Series of instruments will operate in the 12-30VDC range allowing you to be secure in the knowledge that your instrument is receiving the correct amount of voltage regardless of the input power setting.

What is the recommended circuit breaker for my electric gyro?
● Starting current for a 14VDC system is 2.4A max. with a recommended circuit breaker of 3A.
● Starting current for a 28VDC system is .6A max. with a recommended circuit breaker of 2A.
Starting currents and circuit breakers for the RCA EK series are the same as above depending on the voltage system of the aircraft.    

My instrument is showing a climb/dive what can I do?
You can check your aircraft owner’s manual or contact the aircraft manufacturer to determine if your aircraft’s panel is tilted (pitched foreward from 90 degrees). The tilt angle is any deviation from vertical of your instrument panel in level flight. Your instrument needs to be calibrated to compensate for this angle.

My instrument is showing a turn in level flight, what can I do?
It is also very important to have the instrument level (left and right tilt) in your panel. If the instrument is not level it will show a turn when in level flight. To level the instrument place an “L” level on the lip of the bezel at the bottom of the glass and adjust the instrument until the bubble is centered.

How do I get my instrument repaired?
For any overhaul or repair questions you can contact the Service Department at Kelly Manufacturing Company. Go to the SUPPORT page to download an information sheet to send with your instrument.

Do you sell remanufactured instruments?
We do on occasion have remanufactured (we call them Overhaul Certified) instruments for sale. They come with a full one-year warranty like new instruments. Contact us or your favorite distributor for availability.

Frequently Asked Questions