Rating	Revs Per Minute	Boost.     ata   lbs.		Horse Power Nx.    No.		Consumption Litres per hour.
Take off (5 mins). Climb and Combat (30 mins). Max. Continous. Econ. Cruising.	2700 2490 2300 1790	1.42 1.3 1.15 1.05	5.46 3.76 1.63 0.21	1425 1236 1017  722	1390 1205 993 705	381 298 209

DB. 605A. Tested July 1942.

Rating	Revs Per Minute	Boost.     ata   lbs.		Horse Power Nx.    No.		Consumption Litres per hour.
Take off (5 mins). Climb and Combat (30 mins). Max. Continous. Econ. Cruising.	2810 2612 2312 2120	1.42 1.3 1.15 1.05	5.46 3.76 1.63 0.21	1496 1321 1076  884	1496 1321 1076  884	400 310 257

16.           The flaps of both the oil and coolant radiators are thermostatically controlled. The operating fluid is engine oil for the oil radiators, and hydraulic system oil for the coolant radiators' flaps. Control of the coolant radiator flaps by the pilot is possible but normally he will set it to automatic. The flap operation is mechanical, by a wheel and the undercarriage retraction is hydraulic without emergency hand pump.

Cockpit.

17.           The fuselage is clearly designed to be as small as possible to give the maximum performance, and consequently the cockpit is rather cramped for anyone over 6 feet tall. The controls are laid out so that all ordinary ancillary controls are worked by the left hand, the right side of the cockpit having only switch buttons. This layout, combined with the automatic setting of airscrew pitch and of coolant flaps for water and oil, simplifies the task of the pilot.

18.           Details of the controls, which are similar to those on some allied aircraft, are given in the German handbook of which a translation is held in the Enemy Aircraft Section, H.Q., M.E. A photo of the cockpit, consisting of three photos put together, is Figure 6. The rudder pedals are level with the seat so that the pilot is in a good position to resist acceleration; all ancillary controls are convenient to reach and to use.

19.           Owing to the inverted engine, the top of the front cowling is narrow and the view forward on each side is reasonably good. The instruments supplied are:‑

                    Flying
                       combined Artificial horizon and turn indicator
                       repeater compass
                       altimeter
                       air speed indicator

                    Technical
                       Boost gauge
                       R.P.M.
                        Airscrew pitch indicator
                        Oil and coolant temp. (combined)
                        Fuel and oil pressure (combined)
                        Clock
                        Undercarriage lights.
                        Undercarriage mechanical position indicator.
                        Fuel warning light (20 minutes to go).

20.           The hood is small and has no curved surfaces. The thick perspex panels are flat and allow a good view through them. A sliding panel on top and each side allows a clear view in bad conditions. The hood is jettisoned by a red lever on the left side.

Armour.

21.           This is almost identical to the Me.109F-4 and consists of one flat and one curved 10 m.m. plate protecting the back and top of the pilot's head. Three plates, the upper one 8 m.m. and the lower 24 m.m. [Note: This must be two 4 m.m. thick plates as noted elsewhere] protect the pilot's back. A 63 m.m. bullet proof glass shield set at approx. 60° is mounted 13 m.m. behind the 8 m.m. plexiglass windshield. A dural bulkhead consisting of 30 layers of 0.8 m.m. sheet bolted together is fitted to the lower 2/3 of the fuselage cross section. The fuel tank is 'L' shaped and is situated behind and below the pilot. It is of flexible rubber construction enclosed in a plywood box for support and consists of inner and outer layers of hard black rubber and a centre layer of soft self sealing rubber. The capacity is 85 gallons. The oil tank is of unprotected light alloy, ring shaped, fits round the airscrew reduction gear, and holds 8 1/2 gallons. The coolant header tanks are also of unprotected light alloy and are mounted on either side of the crankcase. Occasionally fuel tanks made of unprotected light alloy have been found on Me.109'Es and F's and once on a G. [Note: This was an occasinal trait of lightened high altitude fighters.]

Radio.

22.           The standard German fighter R/T set, FUG VII a, is fitted as on the Me.109F. For further details reports are available through the Enemy Aircraft Section, H.Q., M.E.

Oxygen.

23.           The standard Draeger Unit as on Me.109F is fitted, the supply being drawn from 3 light alloy bottles of normal type mounted on the bulkhead behind the fuel tank. The oxygen-air mixture is regulated by a barometric capsule up to 33,000 feet, above which height pure oxygen is delivered, the rate of flow being controlled all the time by the pilot's breathing, though a hand operated button is provided to give a sudden extra supply if desired at any time.

Compass.


Stalling Speed.

36.           Stalling speed is 102 m.p.h. indicated flaps and wheels down, and 112 m.p.h. with flaps and wheels up. With flaps and wheels up, the ailerons control becomes distinctly lighter at about 140 m.p.h. when the slots open.

Trim.

37.           The trim is effective and not too sensitive. At high diving speeds it becomes almost solid.

Landing.

38.           Approach should be made at 120 m.p.h. indicated.

39.           The aeroplane is rather skittish and the pilot concentrated on keeping straight and did not look at the A.S.I. in the cockpit to see speed at touch down.

40.           From the known stalling speed, the speed at touchdown can be deduced as 105 to 110 m.p.h.

41.           The minimum landing run to be expected in still air with a normal pilot is 550 yards.


Performance.

42.           Climb and speed readings are tabulated on subsequent pages. Results are also plotted as Fig. 1. Speed Fig. 2. Rate of climb Fig. 3. Rate of climb — Different speeds Fig. 4. Rated Height Fig. 5. Time to Height. All tests were done at maximum engine power. (Germans have cancelled maximum emergency power, apparently owing to engine failures.)

Dive.

43.           The dive and shallow dive are very fast. Controls become heavy but large deflections are still possible at 350 m.p.h. indicated. N.B. The handbook warns against rough movement of aileron controls during dive and particularly during recovery, as likely to cause a crash. Limit speed 467 m.p.h.


Endurance.

44.           The petrol consumptions are tabulated on subsequent page. Duration must vary greatly with operational conditions and the time spent in dog fighting; the duration to be expected normally is one hour.

Instrument Flying.

45.           The complete standard German set of instruments was not fitted. Instruments flying is judged to be normal and straightforward.


Night Flying.

46.           Cockpit and exhaust shielding are similar to the 109 F.


Enging Starting.

47.           The engine was always started by hand. It often started at the first attempt and always started (when in our hands) at the second or third attempt. An experienced crew can probably count on a start in good weather conditions at the first attempt.

48.           A small separate tank is provided for the priming pump which can be filled with specially volatile starting fuel for starting in bad weather conditions.



                                                            (signed)  G.M. BUXTON Gp. C. (?)








1.            The Me. 109 G. was made serviceable by 451 Squadron Detachment.

2.            The aeroplane had been restored to standard good condition except that the oil radiator flap was locked open as received, as the functioning of the thermostatic control was apparently bad; no oil thermometer was available; there was a splinter hole and score mark in one airscrew blade.

3.            Close examination of the airscrew blade is therefore made between flights.

4.            During take off, there is a marked swing to the left which occurs towards the end of the run as full power is given. Acceleration is quick and take off run fairly short.

5.            After take off, climb was started, partial climbs being made at each height; full speed level runs were made mostly on the way down. The figures are tabulated in Appendix "A" and the air temperatures for compiling true speeds are tabulated in Appendix "B".

6.            The air filter was cut out at about 8000 feet and was put in again after all tests had been done, before coming in to land.

7.            The propeller pitch control was left in automatic throughout, and the figures of boost and revs given in Appendix "A" are therefore those set by the automatic mechanism.

8.            The radiator flaps were left in automatic and kept the temperature at 80°C most of the time in the easy conditions of cruising used between test runs. The maximum temperature seen was 100°.

9.            The altimeter readings were not exact as the needle was swinging.

10.           At 15000 to 20000 feet in the climb, the engine hesitated and petrol pressure was seen to be low. This immediately rose on switching on the electric pump, and the engine then ran normally.

11.           The engine has some rough periods, but usually, and particularly at high r.p.m., runs sweetly.

12.           Owing to the high rate of climb, it is necessary to allow a margin of up to 3000 feet to settle down into a steady climb; thus for timing a climb from 15000 to 17000 feet it is desirable to pull up to climbing speed (e.g. 150) at 12000 feet. In full speed level flights, speed is picked up quickly.
13.           The control is steady and it is easy to maintain accurate speed with reasonable care.

14.           After almost 45 minutes flying, the red fuel shortage (15 minutes to go) warning light showed. Owing to the fuel swishing about, the light shows intermittently and is an effective warning.

15.           In the approach to landing, torque can be distinctly felt and so the engine should be opened up slowly when "rumbling".







1.            A series of 1000 feet timed climbs were done at various heights. Owing to the high rate of climb, and to the fact that the sensitive altimeter needle was swinging over a considerable arc, the time was not likely to be accurate, and therefore climbs at certain heights were repeated for a height difference of 2,000 feet so that any error in timing would have less effect.

2.            The cooling flaps on the radiator are automatically controlled and they open as the engine temperature rises. They are big enough to cause considerable drag when wide open. Therefore they will cause more drag on a long continuous climb and so decrease the performance. To test this point, a long battle climb will be made.

3.            Tests are being continued in cloudy weather as the effects of the up currents and bumps are not thought to be so important as speed in getting some preliminary figures.






1.            On the third tests, repetitions were made of climbs and level speeds which seemed necessary to fill gaps in the performance curves plotted from the previous two test flights. A test was also made to find the rated altitude at 1.3 at: boost and corresponding revs in automatic (i.g. interconnected) airscrew control.

2.            During the climb from 30070 to 32000 feet, the cooling flaps were seen to be wide open, owing apparently to a sticky thermostat. They were adjusted to normal position by using the manual control but the rate of climb obtained must have been somewhat reduced by this.

3.            Some variation was noticed in the airscrew r.p.m. presumably due to the automatic control functioning slightly irregularly.
 
4.            The rated height of the engine was found by doing a steady climb at 200 mph. indicated and noting the boost pressure at each thousand feet. The automatic boost control keeps the boost constant below rated height, and it decreases above. By plotting a graph of boost against height, the line of the decreasing boost can be drawn and this meets the position of 1.3 boost at 21300 feet which is taken as the rated height as governed r.p.m. (2750).

5.            Level speed was tested at 23,200 feet (true) which gave 262 m.p.h. indicated equal to 378 m.p.h. computed.






1.            The original good maintenance crew under Sergeant Osborne left with their squadron, and a new crew has taken over. No.4583 Sergeant Dill-Franzen of No. 7 S.A.A.F. came to change the airscrew. The new airscrew is in normal adjustment and appears to give the same results.

2.           During take off, the engine was opened up nearly to full power, and firm right rudder was needed to stop swing to left. Take off run is tabulated. Landing was made in reasonable tail down attitude, nearly three point, and brakes were initially applied to stop swing, and then both brakes were put on firmly. Landing run is tabulated.

3.            Tests were then made (at 5,000 feet) on stalling. Stall was read first with flaps and wheels retracted, then with flaps and wheels fully down. The figures show that 120 m.p.h. (195 km/hr) is the minimum safe speed of approach, and only gentle turns should be made below 150 m.p.h. (240 km/hr).

4.            Partial climbs from 4,000 to 6,000 feet were then made to find best climbing speed. Radiator flaps were set with the top flap level with the wing flap (control on "RUNE"). An inexplicable quick climb at 160 m.p.h. was repeated and a more normal time was got. Air intake filter was in use.

5.            Partial climbs were then made from 19,000 to 21,000 feet (Altimeter). First 140 m.p.h. climb was probably slow as engine hesitated owing to low fuel pressure which was raised by switching on electrical fuel pump. A repetition was also slow as boost fell during climb owing possibly to slight stickiness of automatic boost mechanism. A similar slight fall of boost pressure happened at the 160 m.p.h. climb, but not on the two others, on one of which r.p.m. was slightly high. The intake filter was of course out for this test. The radiator flaps were in "automatic" and were controlling satisfactorily, the temperature being low and the opening small. The opening did not vary by more than about an inch during this series of climbs.

6.            The engine was rather rough at times at low power, but still is reasonably smooth at full power.

5A.           Meteorological Office, A.H.Q. Levant was asked if any currents could occur which might account for the irregular results at 5,000 feet. They state that an up current occurred locally between surface and 9,000 feet with a maximum of 400 feet per minute at 6,000 feet.




                                                                   17th JANUARY 1943



Take off run               Approx. 270 yards.






SEVENTH TEST.

            A climb to height was made to conclude the programme of partial climbs.
            The climb was made at full throttle with the airscrew in automatic.
            stop watch was started quickly after taking off and operating undercarriage retracting button, i.e. about three quarters of the length of the runway. Subsequent readings were made by looking at the watch. The aerodrome is at 130 feet and the altimeter was set to 130 feet (1015 Millibars) before take off.            

            Between twenty and twenty-five thousand feet the coolant temperature was seen to be low and the radiator flaps were wide open. This must have temporarily reduced the rate of climb. The automatic thermostat must have stuck, and the radiator flaps were set by hand to a small opening.

            To keep the (unknown) oil temperature down, the climb was made at 170 m.p.h. up to 25,000 feet and reduced to 150 m.p.h. from 25,000 to 35,000 feet.

            The oil pressure was steady throughout, one division above minimum.


EIGHTH TEST.

            Test of stall was made with wheels and flaps up and wheels and flaps down.

UP.         About 120 m.p.h. the aircraft began to lose height. The nose did not fall appreciably and there was no tendency to drop a wing and there was still aileron control.

DOWN.       Just below 105 m.p.h. the aircraft began to lose height but again it showed no vices and aileron control was maintained.

            A slight and quick vibration was noticed when just approaching the stall. Several bursts of motor were given when near the stall but it was always possible to check any tendency to swing.


[Reproduction of large tables that would be included in the end of the report, showing meterological, calibration, misc. small details about these test, ie. see from 20. to 30., which are generally just repeating the same Figures 1-5, just in tabulated from has been left out from this reproduction as they contain little useful information. They may be added to this report later on.]