MOONEY
M20TN - MODEL TYPE-S
SECTION V
PERFORMANCE
5 -- 4
AIRPLANE FLIGHT MANUAL
ORIGINAL ISSUE -- 04-02-2008
TRUE AIRSPEED INDICATION
True airspeed indication is included on the instrument panel as an aid to the pilot. This true air-
speed indication is based on the conversion of indicated airspeed (KIAS) with zero instrument
error not calibrated airspeed (KCAS). For this reason the true airspeed indication will normally
be a few knots low at typical cruise speeds. A true airspeed calibration for the Power On, Clean
Configuration based on the primary static system calibration of this manual is given below for
convenience. Actual calibration of both the airframe static system and airspeed indicators can
vary slightly from aircraft to aircraft.
True airspeed indicator correction table; standard temperature day
Power on, clean configuration
Pressure Altitude, ft
KIAS
0
5,000
10,000
15,000
20,000
25,000
Increase KTAS by:
110
1.0
1.1
1.2
1.3
1.4
1.5
120
1.1
1.2
1.3
1.4
1.5
1.7
130
1.3
1.4
1.5
1.6
1.7
1.9
140
1.4
1.5
1.6
1.8
1.9
2.1
150
1.6
1.7
1.8
1.9
2.1
2.3
160
1.7
1.8
2.0
2.1
2.3
2.5
170
1.8
2.0
2.1
2.3
2.5
2.6
180
2.0
2.1
2.3
2.4
2.6
2.8
190
2.1
2.3
2.4
2.6
2.8
3.0
Add 2% of correction for each 10
C above standard temperature
Subtract 2% of correction for each 10
C below standard temperature
Example: 160 KIAS, ISA+20ºC, 25000’ correction = 2.5 + 0.04 * 2.5 = 2.6 KTAS
REMOVABLE STEP
The cruise speed tables herein were established with the aircraft step removed. Aircraft
equipped with a removable step may have it removed or installed by a mechanic. If the step is
installed decrease the true airspeed at normal cruise power setting by approximately 1 KTAS.
LANDING GEAR DOORS
When snow and ice are likely to be present on taxi and runway surfaces, inboard landing gear
doors should be removed. Accumulation of ice and snow could prevent landing gear operation.
If inboard landing gear doors are removed, a decrease in cruise speed and range can be ex-
pected and should be considered in preflight planning. To be conservative the following figures
should be used:
Decrease of true airspeed at normal cruise power setting by approximately 5 KTAS.
RANGE ADJUSTMENT
An approximate adjustment to range data shown in this manual can be made based on flight time
planned with speed adjustment. For example, using the gear door cruise speed decrease for a 5
hour flight will result in a decrease in range of approximately 25 N.M.:
5 HR X 5 KTS =
25 N.M. reduction in range.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
--CAUTION--
Zero wind conditions seldom occur. In addition, varying atmospheric conditions,
aircraft weight, mechanical condition of the aircraft and piloting techniques all
affect the actual flight time and fuel used during a flight.
It is the pilot’s responsibility to determine the actual operating conditions and
plan the flight accordingly.
