Mooney M20TN, Service And Maintenance Manual

Page: 340 / 1169

MOONEY AVIATION COMPANY, INC.
M20TN SERVICE & MAINTENANCE MANUAL
Date
2006
Rev Date
Page 6
34--10--01 -- HEATED PITOT TROUBLESHOOTING
TROUBLE PROBABLE CAUSE REMEDY
Tube does not heat or clear itself of
ice with switch on.
Switch circuit breaker tripped. Reset circuit breaker.
Open circuit. Repair.
Excessive voltage drop between
battery and Pitot head.
Check for bad connections in con-
nectors and cables leading to the Pi-
tot head.
Heating element burned out. Replace Pitot head.
34--11--00 -- AIRSPEED INDICATOR (TRADITION-
AL)
This indicator registers airspeed in knots. Air pressure
difference between impact air (from the Pitot tube) and
static air (from static ports on each side of aircraft tail-
cone) operates airspeed indicator. An electrically
heated Pitot head prevents ice obstruction in flight.
The airspeed indicator dial markings are as follows:
Radial Red Line -- 194 KIAS
Yellow Arc -- 174--194 KIAS
Green Arc -- 66--173 KIAS
White Arc -- 59--110 KIAS
The Garmin G1000 PFD displays airspeed on a rolling
number gauge using an LCD screen “moving tape” dis-
play. The following information is also displayed:
•
Speed indication
•
Speed ranges
•
Airspeed trend vector
•
Vspeed references
The numeric labels and major tick marks on the moving
tape are marked at intervals of 10 knots, while minor
tick marks on the moving tape are indicated at intervals
of 5 knots. Speed indication starts at 20 knots, with 60
knots of airspeed viewable at any given time. The actu-
al airspeed is displayed inside a black pointer. The
pointer remains black until reaching never exceed
speed (Vne), at which point it turns red.
Speed Ranges
A color coded (white, green, yellow, and red) speed
range strip is located on the moving tape. The colors
denote:
Flaps Operating Range – 59--110 KIAS
Normal Operating Range -- 66--173 KIAS
Caution Range – 174--194 KIAS
Never Exceed Speed (Vne) -- 194 KIAS
A red range is also present for low speed awareness.
Refer to the Aircraft Flight Manual Supplement (AFMS)
for speed criteria.
Refer to Garmin G1000 System Maintenance Manual
for service and troubleshooting information.
NOTE:
See Section 27--95--00 for stall warning systems.
34--11--01 -- AIRSPEED INDICATOR TROUBLESHOOTING (TRADITIONAL)
TROUBLE PROBABLE CAUSE REMEDY
Instrument pointer does not indicate
properly.
Leak in instrument. Check for leak and seal case or stat-
ic lines.
Obstruction in Pitot tube. Clean out obstruction.
Instrument pointer oscillates. Leak in instrument case or in Pitot
lines.
Check for leak; seal lines.
34--12--00 -- VERTICAL SPEED INDICATOR
The Garmin GDC 74A provides digital air data com-
putations (including Vertical Speed) to the G1000 sys-
tem. The unit is mounted behind the PFD. Power is re-
ceived from the “Essential” buss. The GDC 74A
connects to existing Pitot/static ports and converts
barometric pressure changes within the static port lines
to aircraft ascent or descent rate.
The PFD Vertical Speed Indicator displays the aircraft
vertical speed with numeric labels and tick marks at
1,000 ft. and 2,000 ft. in each direction. Minor tick marks
are at intervals of 500 ft.
Refer to Garmin G1000 System Maintenance Manual
for service and troubleshooting information.
34--10--01
AUGUST 2010