Calibration Labs
A World or National Altitude record must be confirmed by a Category One lab calibration after the flight. A Category Two calibration will suffice for all other flight confirmations.
For a list of Calibration Labs click here.
Category One Laboratory: All conditions must be met.
- Barometry equipment for calibration shall adhere to the guidelines set in DOT Advisory Circular AC 43-2 B, dated 10/16/80. This AC lists accuracy minimums, temperature corrections and maintenance necessary for mercury manometer systems. A mercury manometer shall be used.
- Pressure measurements must be accurate to + - 5.4 ft. at sea level and 50 ft. at 55,000 ft. Instrument sen sitivity to + - .006 in. Hg.
- Cold soak equipment must be available.
- Lab must be an FAA Approved Station, Bureau of Standards or military facility to ensure periodic inspections of laboratory equipment and procedures.
Category Two Laboratory: All conditions must be met.
- Altitude may be measured by a mercury manometer or a certified sensitive altimeter.
- When a manometer is used, a factory ICAO altitude scale is preferred for use to avoid pressure/altitude conversion errors.
- A certified sensitive altimeter should be new or recently rebuilt. A certification per FAR 43, Appendix E made within 24 months must be on hand as reference for altitude corrections. A table vibrator should be used to reduce friction effects in the altimeter. Calibrations shall run as the altimeter was calibrated, during ascent. The altimeter shall have a sensitivity of 5ft at sea level and 20 ft. at 30,000 ft.
- Repeatable accuracy to + - 10 ft. at sea level (.01 in Hg) and to + - 40 ft. at 30,000 (.02 in Hg) must be demonstrated.
- FAA Approved Stations are preferred, persons sensitive to the specific needs of soaring pilots are permitted.