100 Hawk sofr China

Pilot's Manual for the Curtiss Tomahawk

[This material is adapted from 100 Hawks for China: The Story of the Shark-Nosed P-40 That Made the Flying Tigers Famous with contributions by Daniel Ford, Erik Shilling, and Tye Lett, copyright 2014 by Warbird Books.]

This manual probably accompanied the AVG Tomahawks to Rangoon. It was published by the British Air Ministry, and the title page says Tomahawk I. However, internal evidence (the engine designation and references to the RAF blocks from which the China-bound Tomahawks were taken) tie it to the Tomahawk IIBs sent to Burma for the AVG. There is also some internal evidence (including references to French instrumentation) suggesting that the text was not brought entirely up to date.

I copied it in 1989 at the National Air & Space Museum, which in turn had copied it from Larry Pistole's large collection of AVG memorabilia. Pistole's collection was later acquired by the Flying Tigers Association. I have no idea what finally happened to either copy of the manual.

I follow the original as exactly as possible, including spelling and typography. Words in brackets [like this] have been added. Comments beginning DF: are mine; those beginning ES: are by Erik Shilling, a pilot with the AVG. Erik's comments (with other information) seem to suggest that the planes sent to China may have had components of older aircraft installed, possibly so Curtiss could use up its inventory of parts, and that the planes were actually closer to IIA models than the IIBs shown in Curtiss records. -- Dan Ford

Pilot's Notes



1. The Tomahawk I is a single-seater, low wing, monoplane with retractable landing gear and enclosed cockpit, powered with an Allison V-1710-C15 engine, which drives a Curtiss multi-position, constant speed, electrically operated, tractor propeller. The following are the main dimensions:

Span 37 ft., 3 1/2 in., Overall length 31 ft. 8-9/16 in.

Overall height with tail down 9 ft., 7 in.

2. The cockpit is totally enclosed. The windscreen is in three sections of laminated glass and behind the windscreen there is a section of 1-1/2 inch glass for protection from gunfire. The transparent cabin cover slides fore and after for entry and exit purposes. An emergency release is provided by which the entire sliding section has an emergency exit on the port side, for us in event of turnover. The structure behind the pilot is of sufficient strength to withstand a turnover landing. Three pieces of armor plate are provided; one piece 7 mm. thick ahead of the pilot from the windscreen line down to the top of the engine, a piece 7 mm. thick behind the pilot's back, and 9 mm. thick behind his head.

3. The main plane is a cantilever multi-spar, skin stressed type built in two pieces and joined at the centerline of the airplane. The wing tips are detachable. The joint where the two wing sections are connected will serve as a skid in case of an emergency landing with the wheels retracted.

The ailerons are both dynamically and aerodynamically balanced. They are operated by the conventional stick control. A fix type trimming tab, adjustable in the ground is provided on each aileron. The ailerons have a stressed metal skin leading edge and are fabric covered.

The flaps are of the split trailing edge type, extending from the aileron to near the centerline of the airplane and are operated hydraulically by an electrically driven pump or by an emergency hand pump. An indicator on the instrument boards shows the position of the flaps at all times when the battery switch is on.

4. Cooling system - Air passing through prestone radiators and oil cooler and exhausting into a common exit duct. Airflow through this duct is controlled by cowl flaps operated by a lever on the starboard side of the cockpit with a locking device incorporated.

5. Wing Guns - Two rifle caliber guns may be carried in each panel. Wing gun charging handles are located on the centerline of the airplane beneath the instrument panel. Ammunition boxes hold 500 rounds per gun. The trigger switch is located on the stick.

6. Fuel Tanks - The fuel is carried in three tanks two in the center of the wing and one in the fuselage aft of the pilot. The total capacity of the three tanks is 132.6 imperial gallons. (See fuel system diagram.) All fuel tanks have "Superflexit" covering. [DF: See Erik's comments in Part II about fuel tanks. The reference to Superflexit suggests that the Tomahawk IIB had an exterior membranes. At first I believed that this was a carry-over from an earlier version of the manual, but it tracks with Erik's recollection.]

Oil Tank - Oil is carried in a 12.7 imperial gallon tank in the fuselage behind and above the fuselage fuel tank. Climbs up to 60° and dives up to 90° should be performed only with not less than 1/3 of the maximum oil capacity. The tank should be refilled to 9.6 imperial gallons maximum service capacity at all times.

Coolant Tank - The coolant expansion tank is forward of the firewall and has a capacity of two imperial gallons.

7. The fuselage is of semi-monocoque, skin stressed construction, and has a motor mount of welded steel tube and steel forged links. The fuselage access door is on the port side of the fuselage near the tail.

8. Fuselage Guns - Two synchronized guns may be carried just ahead of the pilot. These are .50 caliber Colt guns, and are charged directly through an opening on each side of the instrument panel. Electrically operated rounds indicator are mounted near the instrument board on the upper longeron. The gun triggers are electrically operated by a selector switch located above the port longeron, and the trigger switch is located on the stick. Ammunition boxes hold 380 rounds per gun.

9. Battery - a 34 ampere hours capacity, 24 volt battery is carried in the airplane and is accessible through the fuselage access door.

Remains - A Story of the Flying Tigers

10. Landing Gear - The landing gear is equipped with oleo-pneumatic shock struts which are hydraulically retracted to rotating backward about a trunion at the top of the strut. During retraction the strut is rotated 90° about its longitudinal axis by gears, so that the wheel lies flush in the wing. The gear is locked in both the up and down positions by hydraulically operated mechanical locks. The upper half of the strut has members attached to take side and drag loads and is attached to the lower half of strut through a scissors to take torque. The landing gear is equipped with 30 inch diameter smooth contour tires and wheels with 12 x 2 1/4 inch hydraulic brakes. An indicator on the instrument panel shows the position of the landing gear at all times when main battery switch is turned on.

11. Tail Wheel - The tail wheel assembly consists of a standard steerable knuckle unit and a 12 1/2 inch heel with earth conducting tire. The steering mechanism disengages at approximately 35° deflection from the longitudinal axis and when disengaged will swivel through 360°. The tail wheel is fully retractable and operates "clam shell" doors which enclose it completely after retraction. An indicator on the instrument board shows the position of the tail wheel at all times when the battery switch is turned on.

12. Fixed Tail Surface - The tail plane and fin are of all metal constructions attached in fixed alignment to the fuselage.

13. Control surfaces - The rudder and elevators are aluminum alloy construction, fabric covered. They are dynamically balanced and are equipped with trim tabs controlled from the cockpit. Rudder and elevators are controlled by the conventional pedals and stick.

14. Additional Equipment - In addition to the armament, the airplane is equipped with parachute flares, landing light, recognition device, oxygen, life preserver, radio, map case, engine and cockpit covers, navigation, formation, identification and cockpit lights. (See Section 1.)

15. Tie Down Rings are located inboard of the wing tips on the underside of the wing and marked "Tie Down".

16. Tool Box - A tool box for carrying the airplane and engine tool kit as an overload is provided in the fuselage and is accessible through the fuselage access door.

17. First Aid Kit - is located on the port side of fuselage being accessible through fuselage service door.

18. Propeller - The propeller is a Curtiss multi-position and/or constant speed type. The propeller is operated electrically from the airplane electrical supply thru brushes mounted in a housing, attached on the engine section, to slip rings mounted on the rear boss of the propeller hub, and thence to the pitch changing motor.

Automatic electric cutout switches limit the pitch range for ordinary operation and give high and low pitch settings.

Two types of control, manual selective and automatic, are available for selection by the pilot. The change from one to the other is made by a toggle switch located on the propeller control panel. (See Section 1, para. 11).


Pilot's Controls and Equipment


This section gives the location and, where necessary, explains the function of the controls and equipment in the pilot's cockpit.

NOTE: On aircraft Nos. A.H. 741 to A.H. 970 inclusive certain of the electrical switches are "on" when in the "Up" position and care should be taken to identify these. All switches are clearly marked "Off" and "On".

1. Cockpit - The cockpit is fully equipped and has the normal stick and rudder pedal controls which are dealt with individually in the following paragraphs. The sliding hood can be pushed right back from the cockpit and is operated by a crank mounted on the upper right longeron. A pin on the crank engages hole sin the drum and locks the cabin in the full back, full forward and intermediate positions.

An emergency hood release is also fitted and is a lever painted red, located at the top forward frame of the cabin roof. In case of an emergency, while in flight, the entire enclosure may be released from the fuselage by pulling on this lever. In the event of turnover on the ground, pull the panel release handle and push open the emergency exit on the left hand side of the cabin enclosure. This emergency exit may be operated from the outside by means of a handle located on the lower rear left hand cabin frame.

An emergency release which disengages the catches from the crank is located at the top of the windshield and consists of a turnbuckle and wire painted red. This eliminates winding the crank for rapid opening but the enclosure must then be pushed back by hand.

A ventilator for the cockpit is operated by a push-pull control located below the instrument board on the port side. When the control is pulled out hot air is admitted to two vents,: one permitting hot air to enter directly into the cockpit, the other deflects the hot air between the windscreen and bulletproof safety glass, acting as a defroster, before passing into the cockpit.

2. The seat is adjusted vertically by a lever on the starboard side of the seat. The lever is moved upward and to the rear permitting the seat to be raised manually. A release lever controlling the position of the pilot's harness belt is provided at the port side of the seat. To operate, push button on top of lever and move lever to rear locking position. This permits free movement of the pilot in a fore and aft direction. A pilot's relief tube is suspended from the bottom of the seat.

Flying Tigers
revised and updated

3. Control Column - The control column is of the conventional design. The control column hand grip has two switches; the one on the top of the grip is a push button and operates the landing gear; the other is a trigger switch and operates the firing of the guns. [ES: Ours did not have the top button. The hydraulic switch was a light weight switch just below the pistol type control handle, and operated by the little finger.]

4. Rudder Pedals - The rudder pedals are of conventional design and they are adjustable for leg reach by releasing a pin by means of the lever on the inboard side of the pedal, and moving forward or aft as required.

5. Brakes - Brakes are operated by toe pedals and the parking brake lever is located below the instrument board and may be engaged by being pulled back when the pedals are depressed. It is automatically disengaged when the pedals are depressed.

6. Trim Tabs - The adjustable trim tabs for the rudder and elevators [sic] controls are located at the port side of the cockpit near the pilot's seat, and work in the same plane as the controls concerned. The elevator wheel has a crank handle for rapid adjustment. Dials at the hand wheels indicate the positions of the tabs. [ES: the ailerons [also had] a cockpit trim control which was located in front and just below the rudder trim vertical to the rudder trim.]

7. Retractable Landing Gear - The retractable landing gear is operated hydraulically by either the emergency hand pump or the electric pump. An operating instructions plate is locate don the left hand side of the cockpit. On aircraft Nos. A.H. 741 to A.H. 999 and A.K. 100 to A.K. 155 inclusive, a selector lever extends forward along the port side of the cockpit and has a push button on the end which must be depressed to move the handle from neutral. (The handle may be returned to neutral without depressing the button.)

To retract the landing gear depress the button on the end of the handle, and raise the handle to the "Up" position. Then operation the electrical pump by pressing the switch button on the top of the control column. As a precaution the gun selector switch should be "Off" in case the trigger switch is squeezed by mistake. The switch must be held "On" during the period required for the retraction of the landing gear. To lower landing gear move handle to down position and operate switch button as before. [DF: Note what Erik says above, that on the AVG Tomahawks the button on top of the stick was replaced by a toggle below the pistol grip.]

NOTE: - On aircraft A.K. 156 and onwards the push button on the undercarriage selector lever is replaced by a safety latch bolt which must be pulled forward before the lever can be moved.

To ensure positive engagements [sic] of the locks, the switch should be held on for a few seconds after the indicator and the warning horn show that they are down. As a final check the pilot should try and move the hand pump lever on the right hand side of the cockpit. If this lever cannot be moved, except by a high load which brings the hydraulic bypass valve into operation, the pilot can be sure that the landing gear is locked down. The selector lever should then be raised to its neutral position. This hydraulic valve control lever should be in neutral when taking off or landing.

An indicator on the instrument board indicates the position of the landing gear whenever the battery switch is turned "On." A warning klaxon which operates when the throttle is closed with the wheels retracted, is only connected to the locks and consequently will sound when the wheels are down if the locks are not engaged.

This klaxon circuit is controlled through a toggle switch which is mounted just ahead of the throttle quadrant and is actuated by a cam mounted on the throttle rod. This came may be pulled out to turn the klaxon off temporarily during a throttled dive with the wheels retracted. It engages automatically when the throttle is opened to the stop.

Emergency operation: In the event of the electrical system failing, select the required position for the undercarriage on the selector lever and operate hand pump on right hand side of the cockpit.

Warning - Never operate pump with selector lever in "Up" position when airplane is resting on its wheels.

[ES: In the event of electric failure the gear was dropped by operating the emergency hydraulic hand pump. In the event of a hydraulic failure, the handle was removed from its normal position, and placed on a second position outboard of the normal position. In this position, would direct pressure to the main gear and lower the mains, but it would not lower the tail wheel which was left retracted.]

Before starting engine or taxiing, check landing gear lock by shifting selector to "down" position and operating the hand pump until it is solid to fore and aft movement. Return valve lever to neutral position.

8. Wing Flaps - The wing flaps are operated hydraulically by either the hand pump or an electrically operated pump. The selector handle is located on the port side of the cockpit beside the pilot's seat and moves fore and after; - forward for "Down" and after for "Up" and neutral for "Off". The hand operated hydraulic pump (see para. 7) may be worked back and forth to raise or lower the flaps after the up or down position has been selected on the handle. The flaps may be operated manually in order that partial setting may be obtained more easily. With aid loads on the flaps they will close automatically as soon as the selector switch is moved to the "Up" position.

[ES: our flap control lever had a push button on the end which had to be depressed in order to move the flap handle out of the neutral position. When placed in the up position, the little finger was used to turn on the electric hydraulic pump. The same switch was used to acctuate the hydraulic pump both for the Flaps and Gear.]

NOTE: - Flap selector lever cannot be set to "Up" position until undercarriage lever has been returned to neutral. [ES: We did not have this type of flap control.]

9. Undercarriage and Flap Position Indicator - The position indicator is located on the lower port side of the instrument board. The wheel and flap images simulate the actual position of the landing wheels, tail wheel and flaps. The images disappear from view when the electrical power is off, thereby indicating failure of the instrument, or open battery or generator circuit. The batter switch must be "On" to maintain operation of the indicator. The battery switch should be "Off" before leaving the airplane.

Poland's Daughter

Engine Controls

10. Throttle Quadrant - The throttle, automatic mixture and propeller controls are located on the throttle quadrant. The mixture control locates the automatic rich and automatic lean positions. Approximately the last 10° movement of the "lean" mixture on the quadrant is the engine "idle cut-off" position. There is a spring stop included to prevent mixture control from entering the "idle cut-off" position when normal pressure is applied.

11. Airscrew Operating - This may be either "Automatic or "Manual Selective". When on automatic control, a selected engine speed is held constant by an engine driven governor. Speed selection is accomplished by adjustment of the propeller control on the throttle quadrant, and the toggle switch on the propeller control panel is in the "down" or "on" position.

When on manual selective control, that is with switch in "Hand control" position, the propeller acts as a controllable pitch propeller by the operation of the "Increase R.P.M.", or "Decrease R.P.M." switch. Circuits are independent of the governor so that if the governor fails the propeller can be used as a multi-position controllable propeller.

Since the markings on the propeller control are for approximate settings, the tachometer should be relied up to obtain the desired R.P.M.

General Operation: Automatic Control - Set toggle safety switch which is of the circuit breaker type to "On" (Down) (automatic control) position at all times that constant speed control by C.P. lever on throttle quadrant is desired. (If the switch throws out it may be reset by turning to "Off" then to "On". Successive throwing out will probably be an indication of short circuit or overload and the switch should be left off, in this event, the pitch should be changed only if absolutely necessary.)

The desired R.P.M. can then be obtained by moving the constant speed control lever on the throttle quadrant.

Manual Control - Set switch from "on" (automatic control) to "Hand Control". The throttle quadrant lever is then cut out and any change in R.P.M. must be made by operating the manual switch over to "Increase" or "Decrease" until the desired changed in engine revs has been made.

[ES: The propeller control was a four position toggle switch. Up was automatic, down and left was manual decrease, down to the right was in increase rpm, and center was off.]

Fuel System Diagram

12. The Fuel Cock is located on the port side of the cockpit below the hand fuel pump and marked to show the tanks and capacities. [DF: See the diagram above. Measurements are in Imperial gallons, the equivalent of five U.S. quarts. In the manual this is labeled Figure 4. I omit all other figures because they are too difficult to read.]

13. Fuel Quantity Gauge for the auxiliary tank is located on the instrument board and the front and rear main tanks on the floor of the cockpit.

[ES: Fuel tanks were not as shown. The fuel selector had five positions. 1. Res. 2. Main. 3. Aux. 4. Fuse. 5. Off. The reserve and main tanks were one and the same tank . The main tank was feed by a stand pipe in the main tank and the reserve fed from the bottom of the same main tank. The reserve was used for all take offs and landings. When reserve was selected, fuel was taken from the bottom of the main tank and fed fuel to the engine. In other words the stand pipe used all of the fuel in the main tank, but when the main was selected, it used all, except I believe, a positive amount of fuel giving 20 minutes at METO power. This was a positive indication of exactly how much fuel remained, eliminating the pilot having to rely upon a fuel gage which at best was an unreliable.]

14. Carburetor Air Heat Control - is located on the same bracket as the rounds indicator on the starboard side. The carburetor air intake is a scoop built into the top of the engine cowl. A butterfly valve, controlled from the cockpit, is located immediately above the carburetor air screen and permits either cold or warm air or a mixture of both to enter. Warm air for the carburetor is taken from inside the engine compartment. The carburetor air screen is installed to prevent the passage of any foreign matter into the carburetor. The carburetor air control should always be in the cold position when starting the engine.

15. The Engine Primer is located on the starboard side of the cockpit, just below the instrument panel.

16. Starter - A foot operated electric inertia starter is provided. A foot treadle on the cockpit floor is pushed back to operate a starter switch which allows a direct flow of current from the battery to the starter motor. When the starter has reached the desired speed, the foot treadle is pushed forward actuating a starter meshing solenoid and a booster coil; also by the same movement of the foot treadle the start switch contact is broken. The first few impulses of the engine in starting will automatically disengage the starter. On aircraft A.H. 971 and subsequent the foot operated starter is replaced by a two way toggle switch located on the switch panel on the port side of the cockpit. This is depressed to energize the starter and raised to engage it, and the switch automatically returns to the off position when released.

[ES: Starter had the foot treadle starter. DF: This strikes me as particularly significant. All AVG aircraft were taken from blocks higher than AH and therefore should have had the toggle switch. I don't see how Erik could possibly be wrong on this, which leaves only two possibilities: that the manual is in error, or that the planes diverted to China were not equipped the same as those sent to North Africa for the RAF.]

Cowboy: interpreter, warlord, one more casualty

In case of battery failure, the started may be cranked by hand with crank and extension provided for this purpose, both being located in rear access compartment. The starter is operated by turning the crank handle which is inserted in the spiral slot provided in the end of the crank extension, on right hand side of engine cowl. Turn the crank with gradually increasing speed until a fairly good rate of speed is obtained. Remove the crank handle and extension. The engagement of the started will then be accomplished by a pull on the hand starter button located immediately above the crank. Caution: Starter crank and extension must be removed immediately after cranking and before actuating starter pull.

17. Oil Dilution Control is located on the switch panel on the port side of the cockpit.

(a) Before stopping the engine when a cold weather start is anticipated, hold the oil dilution control switch "On" for approximately four minutes at 800 RPM and stop the engine with the ignition switch, continuing to hold the dilution control switch "On" until the engine stops. Then turn the standard fuel cock to the off position.

(b) In starting the engine a normal start should be made. After starting the engine, if a heavy viscous oil is indicated by oil pressure that is too high or by oil pressure that fluctuates or falls back when the engine RPM is increased, the dilution valve should be held "On" to dilute the oil and correct this condition. Over dilution will result in a steady low oil pressure and should be avoided if possible.

(c) If the engine heat is excessive when operating the oil dilution control, the heat may evaporate the fuel out of the oil and leave the normal high viscosity oil in the engine. When this condition is encountered, the engine should first be shut off and allowed to cool for fifteen minutes, then re-started and the instructions outlined in paragraph "a" followed in preparing the engine for cold weather starting.

(d) Take-off may be made four minutes after starting the engine if there has been enough rise in oil temperature (40°c. minimum), if the engine holds its oil pressure and if the engine runs smoothly, or, the take-off may be made as soon after four minutes as these conditions are obtained.

18. Hand Fuel Pump Control is located on the port side of the cockpit forward of the throttle quadrant.

19. Radiator Flap Control is located on the starboard side of the cockpit near the floor. It consists of a long lever and a rack. The latter is provided with a stop at each end and may be set for "full open" (handle fully down), "Full closed" (handle fully up), or any intermediate position.

NOTE: Filling points for:

Wing fuel tanks through left hand wing fillet.
Fuselage fuel tanks through rear vision glass, left hand side, forward.
Oil tanks through rear vision glass, left hand side, aft.
Coolant tank through inspection door, top of engine cowl.

Operational Equipment

20. Gun Firing Switch - See Section 1, paragraph 1 [DF: should be para. 3]

21. Switches and Rheostats are located on panel on the left, below the throttle quadrant. Care must be taken to insure that all rheostats are in the extreme "Off" position when not in use, as they are equipped with integral switches.

22. Oxygen - Two oxygen bottles are carried in supports in the aft part of the fuselage, and accessible through the fuselage access door. The oxygen regulator and bayonet outlet are located on the starboard side of the cockpit. (Aircraft Nos. A.H. 741 to A.H. 990 have one bottle only) [ES: We did not have the oxygen as shown since it was a high pressure system, not the low pressure demand system.]

23. Aircraft Flares - Two M-8 type flares are carried in the flush type built-in wing flare racks. Flare release handles are located on the starboard side of the pilot's seat.

24. Recognition Device - A bracket for mounting the damped rate control is provided on the starboard side of the cockpit which actuates the recognition device mounted on brackets near the top of fuselage accessible through fuselage access door.

25. Landing Lamp - A landing light is fitted to the underside of the port wing and is operated by a switch on the main switch box.

26. Formation Lights - for lighting the upper surface of the wing are located in the fuselage aft of the cockpit. These are controlled through a rheostat on the port side electrical boxes. (Aircraft A.H. 971 onwards)

27. Identification Lights - Provisions are made in top of the fuselage aft of cockpit enclosure and starboard rear wing fillet for upward and downward identification lights. The identification light switch box is locate don starboard side of cockpit.

28. Wireless Controls - [DF: This section omitted. The AVG Tomahawks had after-market radios designed for civilian use.]

Miscellaneous Equipment

29. Dalton Computer - Provision is made for the Dalton computer to be inserted in a stowage on the port side of the cockpit. [ES: no Dalton computer.]

30. Shield - An instrument light shield is provided to prevent reflections on the windshield.

31. Fire Extinguisher - is located in brackets on port side of cockpit floor.

32. Map Case - is fastened to the starboard side of the cockpit.

33. Life Preserver - The back cushion of the pilot's seat may be used as a life preserver. [ES: no life preserver.]

The Lady and the Tigers




Note: - These notes should be read in conjunction with the Flying Training Manual, Part 1, Chapter III, which sets forth in detail the technique which is only outlined here.

1. Full details of the equipment of the aircraft are given in Section 1, and pilots should be acquainted with these details, which are only mentioned hereafter when there is some particular point to which attention should be drawn.

(i) Hydraulic system:- The hydraulic system operates the undercarriage, tail wheel and flaps, and a diagram of the complete system is given at the end of Section 1 [DF: diagram omitted].

(ii) Undercarriage:- See Section 1.

(iii) Flaps:- The operation of the flaps is deal with in Section 1. In the event of flaps being required for take-off, it is advisable to operate them manually in order to obtain more easily the partial setting required. This setting should be 20°. When flaps are down, caution should be exercised not to re-set the selector to the "up" position when there is any possibility that the resultant loss of lift might prove dangerous. Flaps should not be lowered at over 140 m.p.h. and should be raised for taxiing.

(iv) Wheel brakes:- These are toe-operated. They are satisfactory in operation and may be applied reasonably hard to restrict the landing run, but the good taxiing qualities of the aircraft do not necessitate their use under normal taxiing conditions.

(v) Gun firing system:- As the guns are fired electrically through a trigger switch on the stick, great care must be taken that this is not depressed accidentally or when operating the undercarriage and flap switch.

(vi) Trimming tabs:- The elevator trimming tab is efficient and not unduly powerful for small movements of the trimmer wheel. The rudder trim is powerful and must be used at all times whenever speed of the aircraft is varied, particularly when the cockpit hood is open.

(vii) Air screw:- See Section 1, para. 11, for main operating instructions. When it is necessary to check the engine revs on the magneto switches, the propeller switch must first be put to the "Hand Control" position, when any fluctuations of revs will show on the rev counter. Care must be taken to see that the switch is returned to the "On" position, i.e., automatic position, so that C.P. lever on the throttle quadrant is again in operation, before taking off.

(viii) Cockpit hood emergency release: - See Section 1, para. 1.

(ix) Fuel, Oil and cooling systems:- Diagrams of these are given at the end of Section 1 [DF: omitted except for fuel; see Erik Shilling's comments on fuel sytem].

Note:- On aircraft Nos. A.H. 741 to A.H. 970 inclusive, certain of the electrical switches are "On" when in the "Up" position and care should be taken to identify these. All switches are clearly marked "Off" and "On".


2. Ensure that the total weight and distribution of the load are in accordance with the weight sheet summary and ascertain that the aeroplane is in all other respects fit for flight.


3. Before starting the engine, check the following:

(i) That the ignition switches are OFF;

(ii) That undercarriage, tail wheel, and flap selectors are in NEUTRAL;

(iii) That constant speed toggle switch on control panel is ON; i.e., in "Automatic Control".

(iv) That wheel brakes are ON

(v) Switch on main battery switch and check undercarriage, tail wheel and flap indicator

(vi) Turn on fuel and check fuel tanks for contents

(vii) Check controls for free movement.


Note: For main engine details see Handbooks and paragraph 27 of these Notes.

4. (i) If engine has been standing, turn over by hand.

(ii) Turn carburetor air to "COLD", radiator shutters to "SHUT".

(iii) C.P. control to 2800 r.p.m.

(iv) Throttle to give approximately 800 r.p.m.

(v) Mixture control to idle cut-off. (See note)

(vi) Wobble pump to 4 lbs. pressure.

(vii) Prime engine with two to four strokes

(viii) Mixture control to FULL RICH

(ix) Switch ON

(x) Push heel on starter pedal to energize starter.

(xi) When starter has reached sufficient speed, push down toe of starter pedal to engage.

Note:- Do not increase fuel pressure above 4 lbs. with the mixture control out of the idle cut-out position. If necessary, prime the engine to keep it from stalling, as pumping the throttle does not prime the engine.

Tales of the Flying Tigers


5. (i) Warm up at 800 to 1000 r.p.m.

(ii) Minimum oil temperature before running up over 40°C. - Maximum 85°C.

(iii) Oil pressure - 60 to 80 lbs.

(iv) Radiator temperature for running up - 80°C.

(v) Whilst warming up the engine, check the operation of the flaps.

(vi) Set propeller switch to "manual selective".

(vii) Check the functioning of the engine and magnetos at 2200 r.p.m. and 26 in. Hg. (65 Cm.Hg.)

Note:- Care must be taken to see that the tail does not lift when 1800 r.p.m. is exceeded, and it is advisable to have somebody holding this down whilst running up.

(viii) Reset propeller switch to "automatic" position and check C.P. controls.


6. Owing to the steerable tail wheel, brakes are not necessary in normal circumstances. The view ahead is average and the machine is readily controllable.

If the engine is kept ticking over for any period of time, it should be cleared by being run up against the brakes prior to take-off.


7. Prior to actual take-off, check the following points by means of some suitable reminder, such as "T" - "M" - "P" "FLAPS" - "RADIATOR"

(i) "T" - trimming tab controls for rudder and elevator should both be in neutral as shown by the marks on the indicators.

(ii) "M" - mixture control should be at full rich.

Note:- It should be at auto-rich if aeroplane is above 3500 feet.

(iii) "P" - constant speed control should be set to give 3000 revs, and check that toggle switch is in the UP (automatic) position.

(iv) "FLAPS" - may be used up to 20° for take-off if required, although the advantage of so doing is very small. See paragraph 1 (iii).

(v) "RADIATOR" - position for this will be dependent on the outside air temperature.


8. The aircraft is very easy to take-off and shows scarcely any inclination to swing, although a little right rudder may be needed. As the Allison engine has a particularly quick pick-up, the opening of the throttle must be done slowly and care must be taken to ensure that the specified maximum manifold pressure of 41 in. Hg (104 Cm.Hg. on French instruments) is not exceeded. See para. 27 for full engine take-off limitations.


9. (i) Once clear of the ground, raise the undercarriage and tail wheel by pressing the release knob on the end of the undercarriage selector lever, bringing the lever up to the undercarriage "UP" position, and pressing the thumb operating switch on the top of the control column. [DF: Erik says that on the AVG Tomahawks the button on top of the stick was replaced by a toggle below the pistol grip.] This operation is rather slow and whilst the undercarriage is going up -

(ii) reduce the boost pressure to 35 in. Hg. and reduce revs to 2600, and

(iii) maintain a flying speed of approximately 140 m.p.h.

(iv) When the indicator shows that the undercarriage and tail wheel are finally up, check that they are locked into position by operating the emergency hand pump, and if it is solid then the undercarriage and tail wheel are full retracted. Return undercarriage selector lever to neutral position, and

(v) If lowered, raise the flaps by selecting the "Up" position on the flap selector lever, and press the thumb operating switch on the control column. When the flaps are up return the lever to neutral.

(vi) Set mixture control to automatic rich.


10. If the engine should fail during take-off, put the nose of the machine down and maintain flying speed. See that the undercarriage has commenced to come up and, if possible, select the "DOWN" position on the flap lever and give any possible assistance with the hand pump.

(i) Switch off and land straight ahead.


11. Whilst climbing away, check cockpit instruments systematically.

(i) Best climbing speed up to 14,000 feet is approximately 150 m.p.h.

(ii) R.P.M. and boost as given in para. 27.

(iii) Mixture in automatic rich.

(iv) Radiator control adjusted to keep coolant temperature between 85°C minimum and 12585°C maximum.

Taildragger Tales


12. For high speed cruising the r.p.m. may be 2600, with manifold pressure at 35 in. Hg. and mixture control in automatic rich.

For normal cruising the r.p.m. should be 2280 with manifold pressure at 27.9 in. Hg. and mixture control in Automatic Rich.

For most economical cruising, set revolutions to 2190 and manifold pressure to 25.2 in. Hg. Switch propeller control from Automatic to Manual and weaken mixture on mixture control until engine shows a drop in revs of 40 to 50 r.p.m. Switch propeller control back to Automatic. Provided no change is made altitude or cruising conditions this will be most economical condition.


13. Whilst this aircraft has a good view and is very maneuvreable, it is directionally unstable, and this instability most pronounced with the cockpit hood in the fully open position. It is necessary to use the rudder on all turns and it is also necessary to readjust the rudder bias for all changes of speed. As speed is increased the aircraft tends to yaw to the right, and left rudder bias must be applied. (See para. 14)

The controls themselves are powerful at all speeds. It is possible to obtain high acceleration loadings by coarse use of the elevators. Trimmer tabs are effective.


14. Owing to the directional instability of this aircraft with the hood open, it is essential that the hood be shut before any blind flying is attempted. It will be necessary to fly with the feet on the rudder bar, and particular care must be taken to avoid yaw. It would be advisable to lower the seat in order to obtain a better view of the instruments, which are somewhat masked by the reflector sight bracket. [DF: The AVG Tomahawks used a jury-rigged optical sight, and some had none at all.]


15. The stalling characteristics of this aircraft are good. At minimum speed the stall is gentle and there is some buffeting and pitching before the wing, generally the right, drops gently, followed by the nose.

At high speed the machine can be stalled as a result of the coarse use of the elevators producing high acceleration loadings, but due warning is received, particularly on the high speed turn, by a shuddering of the aircraft, and loads of over 5g. can be applied to 180 to 200 m.p.h. without the aircraft stalling.

The stalling speeds of the aircraft at normal operational loads, were as follows:

Undercarriage up and flaps up - 80 I.A.S.

Undercarriage down, flaps up - 82 I.A.S.

Undercarriage up, flaps down - 73 I.A.S.

Undercarriage down, flaps down - 75 I.A.S.


16. This aircraft has been spun up to 5 turns and recovery was normal. The commencement of the spin is erratic and the aircraft tends to come out unless held in the spin. As soon as the standard actions for recovery are taken the spin ceases.


17. This machine handles quite normally on the glide both with flaps up and flaps down.

(i) The glide with flaps up is flat and the view ahead is restricted.

(ii) With flaps and undercarriage down, the glide is steep and a good view is obtainable ahead. The lowering of the flaps makes the aircraft slightly nose heavy. Gliding turns with flaps and undercarriage down should be done at 105 to 110 m.p.h. at normal loadings.

(iii) The engine assisted glide is considerably flatter and should be done at 100 m.p.h., but the view forward is rather restricted by the high angle of the nose.


18. The aircraft can be side-slipped, although it is only just possible to hold the nose up and prevent the speed increasing unduly.


19. The maximum permissible diving speed is 470 m.p.h. indicated. [ES: An indicated speed of 470 mph at 20,000 feet was a true airspeed of 658 mph ... or well into compressibility. A speed at which the controls became useless, and the plane could not recover from the dive.... This is what happened to Pete Atkinson over Toungoo.]

(i) Before commencing a dive propeller should be put into coarse pitch to prevent over revving and the throttle should be left slightly open.

(ii) Flaps must never be used in an attempt to reduce diving speed.

(iii) As speed increase the aircraft tends to yaw to the right, this must be counteracted by the application of left rudder tab. With the hood open this tendency to yaw to the right is considerably worse than when the hood is shut.

(iv) As speed increases there is a tendency for the aircraft to become left wing low and roll to the left, which must be counteracted by the ailerons.

(v) Rate of descent is extremely rapid and speed is picked up very quickly.

(vi) Recovery is normal but elevators are powerful and considerable acceleration loads will result if too much force is used during recovery.

Rising Sun Over Burma


20. Subject to any current restrictions, normal aerobatics may be carried out on this aircraft. Due to the controls being powerful and moderately light the aerobatic qualities are good, but great care must be exercised to see that all aerobatics are carried out at sufficient height to enable the pilot to recover from a dive without exerting excessive loads on the aircraft. Care should also be taken to ensure that speed is maintained during aerobatics in the looping plane.


21. This aircraft is very easy to land, but the following features should be noted:

(i) Landing must always be made with flaps down.

(ii) The angle of descent with flaps and wheels down and engine off is steep.

(iii) If an engine assisted approach is made with too much engine, the view ahead is apt to be restricted owing to the high position of the nose relative to the horizon.

(iv) When in the tail-down landing position this aircraft is at a considerable angle of attack so that if a 3-point landing is desired, some excess speed must be held in order to give sufficient elevator control to change the attitude of the machine from the steep gliding angle to the landing attitude, and to overcome any tendency to stall when making this change.


22. Reduce speed during the initial circuit of the aerodrome and -

(i) Open hood,

(ii) Ensure mixture control is in full rich,

(iii) Carry out the following vital actions in good time prior to the final approach, as the undercarriage takes some time to come down,

(iv) "U" - undercarriage and tail wheel down; depress button on the undercarriage selector lever and select "Down" position and press the operating switch on the top of the control column. [DF: toggle switch on the AVG Tomahawks?] Check that the undercarriage and tail wheel are locked down by operating the emergency hand pump. Undercarriage and tail wheel are fully down when this is solid. When down, return selector lever to neutral.

Note:- Do not lower undercarriage above 175 m.p.h.

(v) "P" - pitch. Set constant speed control to give 3000 r.p.m., and check that the toggle switch on control panel is "ON" (in the down position).

(vi) "F" - flaps. When in the correct position for the final approach, select "flaps down" on the flap selector lever (lever forward), and press the thumb switch [DF: toggle switch on the AVG Tomahawks?] on the control column until flaps are fully down. Do not lower flaps at over 140 m.p.h.

Note:- In the even of failure of the electric motor, undercarriage and tail wheel and flaps may be operated by selecting the required position on the selector levers and operating the emergency hand pump.

(vii) Radiator closed as necessary.


23. The final approach should be done at the following speeds under normal load conditions:

(i) For the engine off approach, a speed of 95 to 100 m.p.h. should be maintained. This will give a steep angle of glide and a good view will be obtained of the landing area. Control at these speeds is good.

(ii) An engine assisted approach should be carried out at approximately 90 to 95 m.p.h. For this, very little engine is required and if too much engine is used, whilst serving to reduce the approach speed slightly, the angle of approach is too flat for the pilot to obtain a satisfactory view of the landing area.


24. (i) The landing itself is easy, but if a 3-point landing is made, the angle of attack as the aircraft settles on to the ground is high, and if the flattening out process has been commenced too soon it might be possible to stall the aircraft and drop a wing, and this point should be watched.

(ii) Normally there is no tendency for this aircraft either to drop a wing or to swing after landing.

(iii) Brakes may be applied to reduce the landing run.

(iv) Flaps should be raised as soon as the run is finished and before taxiing in, but care must be exercised to see that the undercarriage and tail wheel selector lever is not moved instead of the flap lever.

Note:- If this mistake is made, the tail wheel will retract first before the undercarriage, so that the pilot should have warning that he has made a mistake and should cease to press the thumb operating switch immediately. [DF: toggle switch on the AVG Tomahawks?]


25. In the event of a forced landing, the pilot must decide whether or not it is advisable to lower the undercarriage or whether the landing should be carried out with the undercarriage retracted.

(i) If in doubt, decide to land with the undercarriage up;

(ii) Turn off the petrol and switch off engine; open hood.

(iii) Lower the flaps to reduce forward speed.

(iv) In the event of a forced landing on water, undercarriage, tail wheel and flaps should be UP. Hood must be open and harness done up.


The Only War We've Got


26. The corrections for position error are as follows:

At 60 mph I.A.S. reading subtract 2.5 mph
80 mph I.A.S. reading subtract 2.5 mph
100 mph I.A.S. reading subtract 0.5 mph
120 mph I.A.S. reading add 1.0 mph
140 mph I.A.S. reading add 3.5 mph
160 mph I.A.S. reading add 5.0 mph
180 mph I.A.S. reading add 6.0 mph
200 mph I.A.S. reading add 8.0 mph
220 mph I.A.S. reading add 8.5 mph
240 mph I.A.S. reading add 9.0 mph
260 mph I.A.S. reading add 10.5 mph

(Using 100 Octane Fuel)

27. The following should be carefully noted:

(i) Limited operational conditions

Take-off* Maximum r.p.m. 3000
Maximum boost at S.L. 41.0 in.Hg.
Maximum boost above 2600 ft. 38.9 in.Hg.
Mixture control below 3500 ft. "Full-rich"
Mixture control above 3500 ft. "Auto-rich"

Climb* Maximum r.p.m. 2600
Maximum boost 35.0 in.Hg.

* Note: - For take-off and climbs of short duration (not exceeding 5 min.) from sea level, the throttle should be adjusted to give 41 in.Hg. and left in this position until the boost falls to 38.9 in.Hg. This boost should then be maintained by adjustment of the throttle. For climbs of longer duration the boost should be adjusted to 35 in.Hg.

Maximum cruising
(mixture control
Maximum r.p.m.
Maximum boost
35 in.Hg.
Maximum cruising
(mixture control
"Auto-rich" or
Maximum r.p.m.
Maximum boost
29.2. in.Hg.
Maximum level
(5 minute limit)
Maximum r.p.m.
Maximum boost
38.9 in.Hg.
Maximum dive Maximum r.p.m.
Maximum boost
38.9 in.Hg.

(ii) Oil Pressure

Normal 60-65 lb./sq.in
Minimum 50 lb./sq.in

(iii) Oil inlet temperatures

Minimum for take-off 40°C
Normal 70-80°C
Maximum 85°C

(iv) Coolant temperature

Maximum 125°C
Minimum for take-off or flight 85°C


28. Note the following:

(i) Fuel capacity (in Imperial gallons)

Main tank 50 gallons [62.5 gal U.S]
Fuselage tank 47 gallons [58.75 U.S.]
Reserve tank 33 gallons [41.25 U.S.]
Total 130 gallons [162.5 U.S.]

(ii) Fuel consumptions (in Imperial gallons per hour):

Approximate consumptions at 12,000 feet are as follows:

Climbing: at 2600 r.p.m. and 35 in.Hg. boost: 84

Cruising: at 2600 r.p.m. and 35 in.Hg. boost: 84
-- (("Auto-rich") at 2280 r.p.m. and 29.2 in.Hg. boost: 52
-- ("Auto-rich") at 2280 r.p.m. and 27.9 in.Hg. boost: 50
-- ("Auto-rich") at 2190 r.p.m. and 25.2 in.Hg. boost: 42

Note: It is possible to improve on the last cruising consumption by weakening the mixture as described in para. 12.

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