CONFIDENTIAL REPORT ON TACTICAL TRIALS – FW190

BRIEF DESCRIPTION OF THE AIRCRAFT

General

The Fw 190 is a small, compact, single-seater, single-engined, low wing monoplane fighter. There are fittings under the fuselage to enable it to carry bombs or a jettisonable fuel tank. It has a fully retractable undercarriage and partially retractable tailwheel. The mainplane is fully cantilever and is fitted with split flaps of metal construction. The flaps have four positions: retracted, 15° for take-off, 30° for use in the event of a balked landing, and fully down for landing. Operation is by means of three electric push buttons.

The power unit is a BMW 801-D, 14-cylinder, 2-row radial engine, fitted with a two-speed supercharger giving the best performance at 9,000 and 18,000 ft [2,745 and 5,490 m|. Between 5,000 and 8,000 ft 11,525 and 2,440 m| the performance of the engine falls off as it is just below the height where the two-speed supercharger comes into operation. The estimated power of the engine is 1,700 h.p. at the maximum power altitude of 18,000 ft. The engine oil coolers and induction system are totally enclosed by an extremely neat cowling and cooling is assisted by an engine driven fan behind the propeller.

The constant speed VDM 3-bladed metal propeller is electrically operated. It is automatically controlled by a hydraulic governor and, if required, manually by an electric switch on the pilot's throttle lever.

The undercarriage is retracted by pushing a red button. The operation for lowering the undercarriage consists of pushing a green button and releasing the undercarriage locks by pulling a lever which is situated on the left-hand side of the cockpit. In the event of an electrical failure, the only emergency method of lowering the undercarriage is by means of this lever, gravity completing the operation. The tailwheel is partially retracted and lowered mechanically by a cable attached to the starboard undercarriage leg. It is fully castoring and can be locked for take-off and landing by holding the control column right back.

All the control surfaces are fabric covered and are fitted with metal trimming tabs which can be adjusted only on the ground. For trimming, the tailplane is adjustable in flight over the range of +5° to -3°. It is operated electrically by two push buttons governing the up and down movements. There is a visual indicator in the cockpit.

The armament consists of 4 x 20 mm guns in the wing and 2 x 7.92 mm machine-guns in the engine cowling. The all-up weight of the aircraft, including pilot, is approximately 8,600 Ib [3,900 kg) and the wing loading is 41.8lbsqft[3.88kg/m2l.

Pilot’s Cockpit

The cockpit is fully enclosed and although rather narrow is otherwise extremely comfortable. The pilot's position is excellent and as his feet are level with the seat, it enables him to withstand high acceleration forces without 'blacking-out'. The positioning of instruments is excellent and all controls fall easily to the pilot's hand, the absence of unnecessary levers and gadgets being particularly noticeable. The front panel is in two pieces, the top containing the primary flying and engine instruments and the lower panel the secondary instruments. Cut-out switches for the electrical circuits are housed in hinged flaps on the starboard side.

The switches and indicators for the operation of the undercarriage, flaps and tail incidence, are situated on the port side. The control column is the standard German fighter type with a selector switch and firing button for guns, and a send/receive button for the wireless.

The cockpit canopy, which is made of moulded plexiglas, is well shaped and extends far back along the fuselage. The bullet-proof windscreen has a pronounced slope which is unusual. The canopy can be slid back for entry and exit and for taxiing, operation being by means of a crank handle similar to that in the Westland Whirlwind. The enclosure can be jettisoned in an emergency by pressing a red lever on the starboard side; this unlocks the hood and detonates a cartridge which breaks the runners and blows the canopy off. Heating for the cockpit appears efficient, and cooling is effected by a small flap on the port side and seems quite sufficient for the pilot's comfort.

Armour Plate

The pilot's bucket seat is made of 8-mm armour plate and in the unprotected gaps behind are fitted shaped strips varying in thickness between 5 and 6 mm. The pilot's head and shoulders are protected by shaped armour plate 13 mm thick and the windscreen is of bullet-proof glass about 1X in thick. Both fuel tanks are self-sealing. The oil tank, which is situated in front of the engine cowling, is protected by a ring of armour plate varying in thickness, and the tank itself is surrounded by a toughened steel ring.

Radio

The wireless installation is the old type FuG7 and the only unusual feature is that there is no wireless mast, there being instead a short aerial between the tail fin and the cockpit canopy.

Oxygen

The aircraft is fitted with standard improved Hohenatem oxygen equipment with Blaser attachment, giving pure oxygen at high altitude. Three bottles of unusual shape are the source of supply. It was not possible to test the efficiency of this equipment but it is understood that the RAE are carrying out investigations and will render a report in due course.

Compass

A Patin Distant Reading Pilot's Compass is installed in the centre of the dashboard and the Master Unit is in the rear of the Fuselage. An aircraft silhouette takes the place of the normal needle and indicates the direction which the aircraft is flying. There is an adjustable verge ring which can be set to any desired course and the aircraft then turned until the silhouette is pointing to the course selected. The compass generally is of excellent design and the dial is situated in a position where it can be easily seen by the pilot. The magnet is many times more powerful than in our compasses, and as a result is less affected by northerly turning and acceleration errors. It is also unaffected by current or voltage fluctuations, or changes in temperature.

Armament Characteristics

The armament consists of:

i. Two MG 17 guns of 7.92-mm calibre fitted above the engine, synchronised, firing through the propeller arc.

ii. Two MCi 151/20 guns of 20-mm calibre, synchronised, firing through the propeller arc are installed in the wing roots about 12in out from the engine cowling.

iii. Two Oerlikon FF 20-mm guns fitted in the wings outboard of the propeller arc.

Gun Buttons and Switches

The guns are fired by means of a button on the front of the control column. A small selector switch at the side of the column enables the pilot to select the following alternatives:

i. MG 17 and M(, 151/20 guns.

ii. Oerlikon FF 20-mm guns.

iii. All guns.

In addition to this it is possible, by means of cut-out switches which are situated on the starboard side of the cockpit, to fire each pair of guns independently. There are ammunition counters in the cockpit for each gun.

Heating

Hot air from the engine cowling is led by means of ducts to the ammunition chutes of the MG 17 guns and thence upwards to the breech mechanism. The Oerlikon FF 20-mm guns are also heated by hot air from the engine cowling. No special provision is made for heating the MG 151/20 guns and it is thought that owing to their position near the engine this is unnecessary.

Sight

A reflector sight, type Revi 12-D, is mounted 1/4 in to starboard of the vertical centre line. The graticule is .5° 48' in diameter, which is the equivalent to approximately 95 m.p.h. for the high muzzle velocity of the German armament. Vertical and horizontal lines are marked off in degree steps from the centre of the graticule. Seven such lines are visible each way, these lines assist the pilot in range estimation and allowing for line.

Harmonization

The harmonization ranges for each pair of guns are:

Two MG 17 guns at 300 metres or 330 yards. Two MCi 151/20 guns at 450 metres or 490 yards.

Two Oerlikon FF 20-mm guns at 250 metres or 270 yards.

The gun lines of the MG 17 guns are not symmetrical about the vertical centre line. The port gun converges whereas the starboard gun diverges with the result that they cross over 1 ft 2 in to starboard. This may be due to incorrect harmonization.

Sighting View

The sighting view, when sitting comfortably in the normal position, is about half a ring jof deflection) better than that from a Spitfire. The view downwards from the centre of the sight graticule of the edge of the reflector plate holder is about 5 degrees. This view is not obtained by elevating the guns (and consequently the sight) relative to the line of flight, but is entirely due to the attitude of the aircraft in flight, which is nose down.

Tactical Trials General

The Fw 190 is considered an excellent low and medium altitude fighter. It is fast, well armed and very manoeuvrable. The fighting qualities have been compared with a Spitfire VB, Spitfire IX, Mustang IA, Lockheed P-38F, Typhoon and the prototype Griffon-engined Spitfire. All aircraft were carrying full war load.

Flying Characteristics

The aircraft is pleasant to fly, all controls being extremely light and positive. The aircraft is difficult to taxi due to the excessive weight on the self-centring tailwheel when on the ground. For take-off, 15° of flap is required, and it is necessary to keep the control column back to avoid swinging during the initial stage of the take-off run. The run is approximately the same as that of the Spitfire IX.

Once airborne, the pilot immediately feels at home in the aircraft. The retraction of the flaps and undercarriage is barely noticeable although the aircraft will sink if the retraction of the flaps is made before a reasonably high airspeed has been obtained.

The stalling speed of the aircraft is high, being approximately 110 m.p.h. (177 k.m./h.) with the undercarriage and flaps retracted, and 105 m.p.h. [169 k.m./h.| with the undercarriage and flaps fully down. All controls are effective up to the stall. One excellent feature of this aircraft is that it is seldom necessary to retrim under all conditions of flight.

The best approach speed for landing with flaps and undercarriage down is between 130 and 140 m.p.h. |209 and 22.5 k.m./h.| indicated, reducing to about 125 m.p.h. [201 k.m./h.| when crossing the edge of the aerodrome. Owing to the steep angle of glide, the view during the approach i.s good and the actual landing is straightforward, the touchdown occurring at approximately 110 m.p.h. The landing run is about the same as that of the Spitfire IX. The view on landing is poor due to the tail-down attitude of the aircraft. The locking of the tailwheel again assists in preventing swing during the landing run.

The aircraft is very pleasant for aerobatics even at high speed.

Performance

The all-round performance of the Fw 190 is good. Only brief performance tests have been carried out and the figures obtained give a maximum speed of approximately 390 m.p.h. True at 1.42 atmospheres b<x>st, 2,700 r.p.m. at the maximum power altitude of about 18,000 ft. All flights at maximum power were carried out for a duration of 2 minutes only.

There are indications that the engine of this aircraft is de-rated, this being supported by the pilot's instruction card found in the cockpit. Further performance tests and engine investigation are to be carried out by the RAH and more definite information will then be available.

Throughout the trials the engine has been running very roughly and as a result pilots flying the aircraft have little confidence in its reliability. The cause of this roughness has not yet been ascertained but it is thought that it may be due to a bad period of vibration at certain engine speeds which may also affect the injection system. |Later it was discovered that the roughness was due to fouling of the Bosch sparking plugs after a short period of running. The fault was cured by fitting Siemens type plugs taken from the BMW 801A engine of a crashed Do 217 bomber.

Endurance

The total of 115 gallons (522 1| of fuel is carried in two self-sealing tanks and each tank is fitted with an immersed fuel pump for use at altitude. A total of 9 gallons |40.8 I) of oil is carried in a protected oil tank. The approximate endurance under operational conditions, including dogfights and a climb to 25,000 ft [7,622 m| is approximately 1 hour 20 minutes. There is a red warning light fitted in a prominent position which illuminates when there is only sufficient fuel left for 20 minutes flying.

Climb

The rate of climb up to 18,000 ft |5,488 m) under maximum continuous climbing conditions at 1.35 atmospheres boost 2,450 r.p.m., 165 m.p.h. is between 3,000 and 3,250 ft/min |15.24 to 16.51 m/sec|. The initial rate of climb when pulling up from level flight at fast cruising speed is high and the angle steep, and from a dive is phenomenal. It is considered that the de-rated version of the Fw 190 is unlikely to be met above 25,000 ft |7,622 mj as the power of the engine starts falling off at 22,000 ft and by 25,000 ft has fallen off considerably. It is not possible to give the rate of climb at this altitude.

Dive

The Fw 190 has a high rate of dive, the initial acceleration being excellent. The maximum speed so far obtained in a dive is 580 m.p.h. |934 k.m./h.l True at 16,000 ft [4,880 m|, and at this speed the controls, although slightly heavier, are still remarkably light. One very g<x>d feature is that no alteration of trim form level flight is required either during the entry or during the pull-out. Due to the fuel injection system it is possible to enter the dive by pushing the control column forward without the engine cutting.

Search View

The view for search from the Fw 190 is the best that has yet been seen by this Unit. The cockpit hood is of moulded plexiglas and offers an unrestricted view all round. No rear view mirror is fitted and it is considered unnecessary as the backward view is so good. The hood must not be opened in flight as it is understood that tail buffeting may occur and that there is a chance of the hood being blown off. This, however, is not a disadvantage for day search as the quality of the plexiglas is excellent. During conditions of bad visibility and rain, or in the event of oil being thrown on the windscreen, the fact that the hood must not be opened in flight is obviously a disadvantage.

Instrument Flying

The aircraft, although extremely light on all controls, is reasonably easy to fly on instruments. There are no artificial horizon or climb and dive indicators, which are naturally missed by British pilots. It appears that instrument flying is carried out by use of the gyro compass, turn and bank indicator, altimeter and air speed indicator.

Low Flying

The good all-round view from the aircraft, particularly over the nose, makes the Fw 190 very suitable for low flying and ground strafing. Another good point is that the sight is depressed, which would probably help in preventing pilots from flying into the ground. In conditions of bad visibility, however, low flying is likely to be unpleasant as the hood must not be opened in flight.

Formation Flying

The aircraft is easy to fly in formation and due to the good view, all types of formation can be flown without difficulty. The aircraft has a wide speed range which greatly assists in regaining formation, but care must be taken to avoid over-shooting as its clean lines make deceleration slow.

Night Flying

The aircraft was not flown at night but was inspected with the engine running on a dark night, with no moon. The cockpit lighting appeared very efficient and did not reflect on the canopy. The exhaust flames viewed from about 100 yards ahead were seen as a dull red halo, and viewed from the beam could be seen from about .500 yards away. The flame can be seen from astern 200 yards away. It is considered that the glare will badly affect the pilot, particularly during take-off and landing. Although the aircraft carried full night-flying equipment, there is no indication that flame dampers are normally fitted. It is possible that the cause of the red flame may be due to faulty mixture.

Engine Starting and Takeoffs

It is possible to start the engine by means of the internal battery, or an external battery, and in the event of emergency by hand. The method of starting is similar to the Me 109, being an inertia system. If the engine is cold it will require running for a considerable time before the oil temperature reaches the safety level for take-off and even with a warm engine some minutes are necessary as the cooling is so effective on the ground. This is obviously a disadvantage and coupled with the fact that the aircraft is not easy to taxi, makes the Fw 190 inferior to our aircr.ift for quick take-offs.

Fighting Qualities

The fighting qualities of the Fw 190 have been compared with various aircraft, and each comparison is dealt with separately. The trials against the Griffon Spitfire were only brief and against the Typhoon had to be abandoned before completion owing to the unsatisfactory state of the engine of the Fw 190.

CONCLUSIONS

The Fw 190 is undoubtedly a formidable low and medium altitude fighter. Its designer has obviously given much thought to the pilot. The cockpit is extremely well laid out and the absence of large levers and unnecessary gadgets most noticeable. The pilot is given a comfortable seating position, and is well protected by armour.

The simplicity of the aircraft as a whole is an excellent feature, and enables new pilots to be thoroughly conversant with all controls in a very brief period.

The rough running of the engine is much disliked by all pilots and must be a great disadvantage, as lack of confidence in an engine makes flying over bad country or water most unpleasant.

The armament is good and well positioned, and the ammunition capacity should be sufficient for any normal fighter operation. The sighting view is approximately half a ring (of deflection) better than that from the Spitfire.

The all-round search view is the best that has yet been seen from any aircraft flown by this unit.

The flying characteristics are exceptional and a pilot new to the type feels at home within the first few minutes of flight. The controls are light and well-harmonised and all manoeuvres can be carried out without difficulty at all speeds. The fact that the Fw 190 does not require re-trimming under all conditions of flight is a particularly good point. The initial acceleration is very good and is particularly noticeable in the initial stages of a climb or dive.

Perhaps one of the most outstanding qualities of this aircraft is the remarkable aileron control. It is possible to change from a turn in one direction to a turn in the opposite direction with incredible speed, and when viewed from another aircraft the change appears just as if a flick half-roll has been made.

It is considered that night flying would be unpleasant, particularly for landing and take-off, due to the exhaust glare and the fact that the cockpit canopy cannot be opened in flight.

The engine is easy to start but requires running up for a considerable time, even when warm, before the oil temperature reaches the safety level for take-off, and this coupled with the fact that the aircraft is not easy to taxi makes the Fw 190 inferior to our aircraft for quick take-offs.

The comparative fighting qualities of the Fw 190 have been compared with the Spitfire VB, Spitfire IX, Mustang IA, Lockheed P-38F, 4-cannon Typhoon and prototype Griffon Spitfire, all aircraft being flown by experienced pilots. The main conclusion gained from the tactical trials of the Fw 190 is that our fighter aircraft must fly at high speed when in an area where the Fw 190 is likely to be met. This will give our pilots the chance of 'bouncing' and catching the Fw 190 and, if 'bounced' themselves, the best chance of avoiding being shot down.

The all-round search view from the Fw 190 being exceptionally good makes it rather difficult to achieve the element of surprise. Here again, however, the advantage of our aircraft flying at high speed must not be overlooked, as they may even if seen by the pilot of the Fw 190 catch it before it has time to dive away.