Mooney Executiv 21 User manual

MODEL M20F
OWNERS
MANUAL
OPERATE THIS AIRCRAFT ONLY- @after reading
owners manual @with owners manual on board
@ after you are fully qualified & understand all of
the aircraft operating characteristics& limitations
MOONEY AlRCRAF7: lNC.

YEAR
P
1967
OWNERS MANUAL
MODEL SERIAL NUMBERS
M20F 660003 & 660004
670001 TWRU 670539
Issued September 1966
Revised March 1967

aboard your new Executive 21. Enjoy the greater utility
of the long, rooiny cabin. The far-ranging fuel capacity
of the Executive
21 now makes possible one-stop trans-
continental flights.
The same high perforinance and low operating cost which
make its sister ships, the Mark 21 and Super 21, the
world's leading sellers
in the retractable-geared class,
arebred into the Executive
21.
Read this manual carefully, it is prepared to help you en-
joy fully the remarkable perfor~nanceand econorn)r charac-
teristics the Executive
2 1 is prepared to deliver.
MBONEY AIRCRAFT, INC.
XERRVIL 1 E TEXAS

This manual contains Federal AviationAgency- DelegarionOption
Authority approved li~nitarionsand nus st be carried in the Execu-
tive 21 at all times.
EXECUTIVE 21
OWNER'S MANUAL
TABLEOFCONTENTS
PART I DESCRIPTION AND OPERATION
OF COMPONENTS
Page
General
Propeller
Engine
Power Boost
Engine Ignition
Fuel System
Electrical System
Airframe
Landing
Gear
Flight Controls
Moaney Positive Control Systen.
Trim System
Flaps
Vacuum System
Brakes
Heating and Ventilation Systems

PART II FLIGHT PROCEDURES
General
Weight and Balance
Pre-Flight Inspection
Entering the Airplane
Starting the Engine
Cold Weather ond Manual Starting
Taxiing and Ground Operation
Pre Take-Off Check
Take-Off and Climb
Power Changes
Cruise Procedures
Indicated Airspeed
Fuel Management
Let-Down Procedures
Land
ing Procedures
Normal Landing
Stopping the Engine
PART I!! SERVICE AND MAINTENANCE
Page
General
Ground Handling
Propeller
Engine
Battery
Care
of Interior
Care of Exterior
Windows
Landing Gear
Vacuum Operated Step
Required Data
Service Bulletins and Instructions

PART IV PERFORMANCE DATA
Take-Off and Climb Data
Climb Performance
Cruise and Range (2500')
(5000')
(7500')
(1 0,000')
(15,000')
Stall Speed
vs. Sank Angle
Maximum Range
& Glide Range
Landing Data
(Fig.
1)
(Fig. 2)
(Fig. 3)
(Fig. 3A)
(Fig. 38)
(Fig. 3C)
(Fig. 3D)
(Fig.
4)
(Fig. 5)
(Fig. 6)
Page
PART V OPERATING LIMITAT IONS
FAA/BOAAPPROVED MOONEY M20F
Page
Power Plant Instruments
Airspeed Limitations
Flight Load Factors
Maximum Weight
& CG Range
Aircraft Instrumentation Markings and
their Significance
Types of Operation
Power Boost
Placards
Instrument Marking (Except Power Plant)
Maximum Altitude Loss in Stalls at Gross Weight
Revised March 1967

PART I
DESCRIPTION AND OPERATION OF COMPONENTS
GENERAL
The Executive 21 is a single engine four-place low wing, re-
tractable tricycle landing gear airplane. The design and opera-
tion of this aircraft are conventional with few exceptions. This
section will describe some of the components of the aircraft
and operating details.
PROPELLER
The Executive 21 uses an alunlinu~nalloy constant speed pro-
peller of
74 inch diameter. The pitch of the blades is controlled
by engine oil pressure which acts to increase blade angle of
attack and thereby control engine speed. The propeller control
in the cabin operates the propeller governor which controls the
oil pressure provided to the propeller hub. The governor
ser-
ting functions to maintain the engine at a constant speed by
actuating blade angle of attack. In essence then, the function
of the propeller control in the cabin is to regulate and maintain
the rotational speed of the engine at a desired setting.
ENGINE
The Executive 21 is powered by the Lyconling 200 hp 10-360-A 1A
four cylinder engine. This engine uses 100/130 octane fuel.
Four rubber bushings on the aft side of the engine provide
mounting and vibration isolation. Engine ~iianifoldpressure
is
regulated by the push-pull throttle control on the panel.
POWER BOOST
A unique Power Boost feature of the Executive 21 provides in-
creased manifold
p re ss u re when operating at full throttle.
This is
a c co 111 p 1 is h ed by pulling the Power Roost control
out, which causes induction air to by-pass the engine air filter
to perinit the engine to operate
on direct ram air. Because
the engine will be operating on unfiltered air when the Power
Boost is used, it should be operated only in clean, dust free
Revised March 1967

air at altitude, and turned off for take-off and landing. Because
the Power Boost is effective only when the throttle is in the
fully opened position, its advantages generally will be realized
at altitudes above
5,000 feet where flight is often with full throt-
tle.
A light is provided on the panel by the Power Boost control
to remind the pilot to push the control in (to filtered air) before
landing. This light will come on when the gear
is lowered
while Power Boost is on.
I WARNING
Do not fly this aircraft in icing conditions.
Turn Power Boost off when icing conditions are
inadvertently encountered. Icing conditions prevail
any time the temperature and inoisture conditions
coixbine to produce the possibility of impact ice.
Using unfiltered induction air when flying in snow
or other
IFR conditions can be hazardous. Snow
can accumulate in the fuel injector impact tubes or
inoisture can freeze in the passages under icing
conditions and cause loss of power. Therefore it
is imperative that the Power Boost not be used when
flying in sleet, snow, rain, or i~~oisture-ladenair
near freezing teii~peratures. Under these condi-
tions ice can for~liin the inlet duct or fuel injector
unit even though no visible moisture
is apparent on
the airframe.

POWER BOOST ON
FUEL-AIR MIXTURE
The fuel injector unit of the 10-360 engine has provisions for
adjusting the fuel-to-air ratio as required at,different altitudes.
The fuel-to-air ratio (mixture) is regulated by the hexagon
shaped push-pull control located between the throttle and pro-
peller controls in the cabin. This control has a vernier adjust-
nlent feature for obtaining precise mixture settings. An exhaust
gas temperature gage is provided to indicate the optiinurn mix-
ture setting.
ENGINE COOLING
The engine baffling directs air flow over the cylinders for cool-
ing in flight. Cowl flaps are provided on the lower cowling to
allow more free air flow on the ground and during low speed,
high power conditions (i.e., climb conditions). Cowl flaps
should always be open on the ground, and prolonged engine
operation on the ground should be avoided to prevent engine
overheating.
A push-pull cofitro'i is provided below the in-
strument panel and to the right of the pilot for operation of th'e
cowl flaps.

.ENGINE LUBRICATION
The engine has a pressure-type wet- sump lubrication system.
It has an eight quart capacity; however, as a general rule, when
the oil level drops below six quarts, one quart
is added. This
will maintain the oil level between the six and seven quart level.
See Part 111 for type of oil used and time between oil changes.
An oil temperature thermostat, located in the oil reservoir,
is set for
180' F. to assure adequate operating engine oil tem-
peratures. The oil cooler is mounted on the lower left side
of the cowling. An oil filter is available as optional equipment.
ENGINE IGNITION
The ignition system has the following features:
1. Two Bendix magnetos, the left magneto being equipped with
a set of retard breaker points.
2. A starting vibrator, located on the upper firewall, which
furnishes a shower of sparks for starting.
3. A switch. which coinbines both ignition and starting functions.
4. Shielded spark plugs and ignition harness to suppress radio
noises.
When the push-type starter switch is activated in the "start"
position, the starter vibrator sends an interrupted current
through the retard-breaker points while the right magneto
is
grounded out. The left magneto then provides a fixed retard and
a long duration, boosted spark for starting.
FUEL SYSTEM
Fuel is carried in integral. sealed sections in the tront por-
tion of each wing root. Each tank will hold
32 gallons of aviation
gasoline
(100/130 octane\. An internally-mounted fuel quantity
indicator (effective
Dn S/N 670074 & ON) can be seen through
each fuel tank filler neck. considering load and range require-
inents. you lxay choose to fill each tank only to its 25-gallon
l~larkon the indicator. Tank vents allow ventilation as fuel is
depleted and overflow when fuel expands in hot weather. The
fnel tanks each have a suinp drain under the wing from which
fuel ]nay be saillpled to check for water or sediment contamina-
tion.
A small plastic cup with anactuator prong is provided to
obtain fuel sa~nples.
If water is present in the fuel, a distinct
line separating the water from the gasoline may be seen through
the plastic cup. Water. being heavier, will be
on the bottom
of the cup, and the light green colored fuel will be on top.
4 Revised March 1967

SAMPLING FUEL FROM MAIN TANKS
Aluminum fuel lines feed the fuel from the tank to a two-way,
positive-setting selector valve on the floor ahead of the pilot's
seat. The selector valve feeds fuel from one of the tanks at a
time, and also has an "off" position for extended periods of
storage or for emergency use. The selector valve also con-
tains a sump drain which
is actuated by pulling the ring adjacent
to the fuel valve handle. Switch the selector valve handle to
the right and left tanks to drain the respective lines. Be sure
sump drain returns to normal closed position after releasing
the .ring. Fuel is fed from the selector valve through the elec-
tric boost pump, then to the engine driven pump and into the fuel
injector unit. The electric boost pump
is turned on for take-off
and landing to provide fuel pressure if the engine driven pump
inalfunctions.

SELECTOR DRAIN VALVE
1 WARNING
Under no circutnstances should aviation fuel of a
lower grade than 100/130 octane be used. Aviation
fuels 1xay be distinguished by their color:
80 octane
is red, 91 octane is blue, and 100 octane is green.
ELECTRICAL SYSTEM
The electrical syscenl is provided with a 50-amp., 12-volt gen-
erator and a
35 amp - hour battery which is located aft of the
baggage compartment. All electrical systems can be turned
off by the master switch which actuates a relay located at the
battery. The inaster switch for the electrical system is located

at the left-hand side of the flight panel. The electrical system
operates all the electrical accessories listed below:
1. Radios
2. Engine starter
3. Starter vibrator
4. Navigation lights and interior lights
5. Landing light
6. Rotatirig beacon (if installed)
7. Heated pitot (if installed)
8. Turn coordinator
9. Cigarette lighter
10. Electric landing gear (if installed)
1
1. Fuel gages
12. Electric fuel puinp
13. Stall warning horn
14. Landing gear warning horn and warning lights
NOTE: The engine has its own separate electrical systelil
and will continue to run, even though the ~naster
switch has been turned off. or even though the ac-
cessory electrical system should malfunction.
Interior Lights
Panel illu~ninationis provided by two adjustable spot lights
mounted on the headliner and individual post lights for the in-
strument panel. These lights are controlled by a rheostat. The
fuel selector valve is illuillinated by a small light lnounted under
the panel on the left side. The intensity of this light is con-
trolled
by rotating the lens housing.
Amineter
The ammeter in the engine instrument clustgr will indicate if
the battery is charging or discWt-ging.
A inalfunction in the
generator or voltage regulator will be shown a3 an ammeter
discharge at flight power settings. A low battery will cause a
high charge indication.
Revised March 1967

Electrical Panel
The electrical panel is divided into two parts:
a. The electrical toggle switches, on the lower left side of the
pilot's panel, act in combination both as on-off switches and
as breaker switches. Should any of these circuits be over-
loaded, the switch auto~~~aticallyturns to the "ofP' position.
These switches are, froin left to right:
1. The electrical fuel puinp
2. An optional equipment switch (Marker beacon)
3. An optional equipment switch (Glide slope)
4. An optional equipment switch (Pitot heat)
5. An optional equipment switch (Rotating beacon)
6. The navigation lights
7. The landing light
b. The breaker switches which are located on the lower right
side of the copilot's panel, are covered by a special breaker
switch cover. These switches are of the push-to-reset
type*
AIRFRAME
The structure of the Executive 21 is of conventional all-metal
design. The cabin section consists of tubular steel structure
covered with alu~ninunlsheet metal. The center windshield
post and the firewall are stainless steel.
'The wing, stabilizer, and fin have
a 11iain spar design and an
auxiliary spar with stressed skin to carry torsional loads. ?'he
tail cone is a conventional semi-monocoque design, The seat
design features contoured construction. The front seats are
adjustable fore and aft and have adjustable three-position backs.
The rear seat back may be retnoved for additional cargo space.
The entire empennage pivots around two attachment points to
the tail cone to provide stabilizer trim.
A screw mechanism
actuates the empennage movement at the rear bulkhead when
the trim control wheel is operated.
Revised March 1967

LANDING GEAR
Manual Systern
The landing gear is unique in that it is manually retracted by
the pilot by means of a lever in the cabin. The systein is op-
erated by direct mechanical linkage and has proven to be one
of the most reliable and maintenance-free retraction systeins
available. An electrically powered landing gear retractipn sys-
ten1 is also available at extra cost and is described in the fol-
lowing section.
The inanual system is aided
by bungee type springs in the fuse-
lage and assist springs in the wing, which balance the weight of
the gear. ~ubberdiscs are used for shock absorption in the
welded steel tube gear structure. Grease fittings are provided
at certain iinportant lubrication points on the landing gear.
The position of the gear is indicated by lights on the panel which
will warn of an unlocked condition. These lights may be dinllned
by rotating the lens housing to prevent glare at night. Press the
lens housing in to test the bulbs. The red indicator light will
coine on if the handle on the retraction lever is not sufficient-
ly engaged in the down and locked position, thereby indicating
an unsafe-to-land condition. The green light indicates that the
handle is properly engaged in the down position, and the gear
is in the landing configuration.
A thumb operated latch is pro-
vided on the down socket to prevent unlocking of the gear when
it is down unless it is deliberately released.
To retract the gear, depress the safety latch button and slide
the gear handle fro111 the down-lock socket. Move the handle
rapidly to the floor between the seats. Slide the gear handle
into the up-lock socket, and the operation is complete. The
more rapid the lnovernent of the handle, the easier it is to re-
tract the gear. The gear retracts easiest at low airspeeds.
To lower the gear, slide the gear handle from the up-lock socket
and move the handle forward to the instrument panel. Slide the
gear handle into the down-lock socket and check the gear warning
light for a gear-down indication (a green light).

Electrical Gear Systein (optional)
The optional electrical landing gear retraction systetn is op-
erated by the wheel-shaped switch on the upper portion of the
flight panel. To raise the gear, the knob is pulled out and the
switch moved up to its upper detent. An "airspeed switch" is
incorporated in the electrical circuit which prevents landing
gear retraction until a safe airspeed is attained.
Never rely on the airspeed safety switch to keep
the gear extended while taxiing, taking off or landing.
Always check the gear switch for the down position.
A litilit switch will stop the gear in its retracted position; the
gear-up light will coine on, and the gear switch will require no
further attention until landing. To lower the landing gear, the
knob is pulled out, ~noveddown, and placed in the lower detent.
A liinit switch will stop the gear system when the proper lock-
ing force has been exerted to hold the gear down, and the green
gear-down-light will come on.
A discharged storage battery lnay prevent the land-
ing gear fro111fully extending.
There are three ways to check that the gear is completely down
and locked:
1. The green "safe-to-land" indicator light (on the left panel)
will coine on.
2. The black indicator marks, as seen through the glass in the
floorboard, will be aligned.
3. Retard throttle fully, and if no warning horn is heard the
gear should be down and locked. The gear warning horn
eniits an interrupted sound of a different pitch than the stall
warning horn.
When these conditions are fulfilled, the aircraft inay be landed
with no further attention to the landing gear syste~i~.

Manual Operation of the Electrical Landing Gear System
If the gear does not come down due to electrical malfunction.
etc., the syste1.11 {naybe operated manually as described below:
1. Pull landing gear circuit breaker to OFF position.
2. Put gear switch in the gear down position.
3. Push crank engage knob forwal-8.
4. Crank clockwise approximately fifty (50) -turns to lower the
gear.
5. Gear is down when green gear light is on. If a total elec-
trical lnalfunctiori occurs. check gear visual indicator.
IJO N0'1' RE'I'RAC'I' GEAR IN 1, LIGII?' IVI'TH MANIIAI> MAN11
CRANK.
FLIGHT CONTROLS
The ailerons, elevators, and rudder operate conventionally.
Push-pull tubes with self-aligning rod end bearings actuate these
control surfaces. The ailerons have a differential linkage (i.e.,
up travel is greater than down travel) to lninilnize adverse yaw
when they are deflected. Gap strips on the hinge line niinirnize
air spillage fro111 the high to the low pre: ;ure side of the con-
trol surfaces. The ailerons have beveled tiailing edges to lower
pilot control force.
POSITIVE CONTROL SYSTEM
The Mooney Positive Control (PC) system provides a high degree
of roll stability by supplying pneumatic inputs to servo units
linked to the rudder and aileron control systeins. Since the en-
gine-driven vacuuu~pu~~lpsupplies the pneumatic power, PC is
'in operation whenever the engine is rucning and the vacuuli~
sys-
tem is functioning properly.
The
PC system cut-off valve located in the pilot's left-hand con-
trol wheel handle provides systell-I cut-off when depressed. The
aircraft can be n~aneuveredeasily when this valve is held down.
When the valve is released, the airplane will tend to return to
straight and wings level flight froin any attitude. The turn co-
ordinator instrlllnent supplies the controlling signals for the PC
system. The "Roll Trim" knob in the turn coordinator provides
an aileron trill-I function. Clockwise rotation triims to the
Revised ,March 1967 11

right; counterclockwise rotation trilns to the left. In the event
of malfunction. the pilot can easily override the systein at any
time. Co~npletedisengagement lilay be accomplished by depress-
ing the cut-off valve. In the event of coinplete loss of vacuum
(indicated by a red light above the gyro horizon), the
PC system
will autonlatically become inoperative. Excluding malfunction
of the vacuuln system.
PC will continue to operate even after a
complete engine power loss as long as the propeller is wind-
milling at approxi~nately 1000 rpm or above.
The turn coordinator operates on both vacuuln and electrical
power, thereby providing fail-safe turn coordinator operation.
This aircraft is not approved for spins. In the event that the
pilot inadvertently approache., or enters a spin, the Positive
Control system can be overpowered from either the pilot's
01-
copilot's side and the controls used for normal spin recovery
techniques. ?'he pilot should use the cut-off valve located in
the pilot's left control wheel handle to cut off the
PC systeix
when employing spin recovery control procedures.
Revised March 1967

While taxiing before take off. the PC system should
be checked -for proper functioning by noting move-
ments of the flight controls in taxi turns. When PC
is functioning properly, the control wheel will tend
to rotate in the opposite direction of the taxi turn.
The absence of flight control 112ovement during taxi
turns, or extreme control movement in either direc-
tion without prompt return to neutral, indicates a PC
malfunction that should be corrected before flight.
The pilot must become familiar with the flight char-
acteristics of the airplane with the PC systein inop-
erative. This is accomplished simply by holding
down the cut-off valve button while making turns and
maneuvers. Frequently check the
PC system during
flight to see that it is functioning properly, particu-
larly if
IFR conditions are anticipated. To check for
a malfunction while in flight, first establish a mod--
erate bank. Then release the controls to see if the
aircraft will return promptly to straight wings-level
flight as shown
by the artificial horizon. Repeat the
procedure with a turn in the opposite direction.
Sluggish, erratic, or incomplete bank recovery warns
of a malfunction in the
PC system, PC is installed
to help alleviate pilot fatigue, but the systein should
be monitored frequently to check for proper function-
ing like any other system in the aircraft.
TRIM SYSTEM
A small control wheel on the floor between the front seats actu-
ates the adjustable stabilizer via a g-sar reduction and torque
tube linkage which actuates the empennage jack screw.
A fric-
tion lock
is provided on the pilot side of the trim control ped-
estal. Rotating the friction screw clockwise increases trim
friction. The position of the stabilizer is indicated by a pointer
on the aft side of the nose wheel well. The intermediate mark
in the pointer range is the normal take-off setting of the trim
control. The trim system also changes the setting of the trim
bungees connected to the elevator horns 20 obtain trim assist
from the elevators.