Piper Aircraft Corporation Malibu Mirage PA-46-350P, Airplane Maintenance Manual

Page: 940 / 1956

PAGE 12
Feb 28/07
5C22
34-10-00
PIPER AIRCRAFT, INC.
PA-46-350P, MALIBU MIRAGE
MAINTENANCE MANUAL
5. Airspeed Indicator
The airspeed indicator provides a means of indicating the speed of the airplane passing through the air.
The airspeed indication is the differential pressure reading between pitot air to pressure and static air
pressure. This instrument has the diaphragm vented to the pitot air source, and the case is vented to the
static air system. As the airplane increases speed, the pitot air pressure increases, causing the
diaphragm to expand. A mechanical linkage picks up this motion and moves the instrument pointer to the
indicated speed. The instrument dial is calibrated in knots, and also has the necessary operating range
markings for safe operation of the airplane.
NOTE: If any connections in the static system are opened for maintenance, the entire system must be
rechecked per FAR 23.1325. With optional Meggitt EFIS installation, see Appendix 1 (grid 5K19).
A. Troubleshooting
See Chart 4.
B. Removal and Installation
See 39-10-00, Face Mounted Instruments - Removal and Installation.
CHART 4
TROUBLESHOOTING AIRSPEED TUBES AND INDICATOR
Trouble Cause Remedy
Pointers on instruments stick Leak in instrument case or Check for leak and seal.
or do not indicate properly. in pitot lines.
Pointer of instrument Defective mechanism. Replace instrument.
oscillates.
Instrument reads high. Pointer not on zero. Replace instrument.
Leaking static system. Find leak and correct.
Instrument reads low. Pointer not on zero. Replace instrument.
Leaking static system. Find leak and correct.
Pitot head not aligned Realign pitot head.
correctly.
Airspeed changes as aircraft Water in pitot line. Remove lines from static
is banked. instruments and blow out
lines from cockpit to pitot
head.