Interview with author Robert Forsyth and book review

When faced with similar design goals and timing to the Grumman Tigercat, Dornier took a radically different approach with their unique Do 335. To minimise the frontal surface area, drawing on earlier experience with the Do 18 and the P.59 (a 1937 patent for a tractor-pusher bomber), the ‘335 adopted the rather weird ‘push-pull’ configuration, with both engines mounted in the fuselage. The forward engine is in the traditional location with a tractor propeller. The aft engine is mounted in the middle of the fuselage (for better weight distribution) and is connected to an aft push propeller with a driveshaft. The resulting surface area is only slightly higher than a comparable single-engine fighter.

A pair of Daimler-Benz DB-603 engines, each producing 1,800 hp, allowed for a maximum weight a little higher than a traditional fighter, armed with a 30-mm cannon firing through the propeller hub and a pair of 20-mm cannons in the cowling. The aircraft could carry a lot of fuel and provided a combat range 30 per cent higher than the Focke-Wulf Fw 190 or Messerschmitt Bf 109. The aircraft was too late to see combat in the Second World War, and only thirty-seven were built. Of these, a few reached conversion units for a short duration, but the type did not see combat.

The design produced tremendous performance; despite having 10 per cent less horsepower, the Do 335 was 14 mph (23 km/h) faster than the Grumman Tigercat.

Japan started work on a push-pull fighter, the Tachikawa Ki-94-I, but it was deemed too complex and was cancelled. (the Do 335 is covered in The Hush-Kit Book of Warplanes Vol 2)

Dornier Do 335 (X-Planes Book 9)

Robert Forsyth’s book on the appealing eccentric Dornier Do 335 is excellent. It is a fascinatingly deep delve into the subject, complete with a generous amount of illustrations and photos (and often quite surprising) personal accounts. The macabre world of an evil empire falling to pieces while at the cutting edge of engineering, and the bizarre combination of logical thinking and human madness is brought deftly to life. We met author Robert Forsyth author of Dornier Do 335 (X-Planes Book 9) to find out more.

What was the Do 335?

A big, brutalist, ‘push-pull’ piece of aeronautical engineering from Dornier which first took to the air in October 1943 and was intended to be a high-speed, all-weather, day- and night-fighter. It was one of the small number of German piston-engined wartime designs to feature a nosewheel.

There were plans for a two-seat Do 335 A-6 nightfighter (the radar operator was to sit facing forward in a raised cockpit above and behind the pilot). The various radar aerials were to be fitted as ‘toasting fork’ aerials to the wings, a pair for the lateral beams on the port side and two for the vertical on the starboard side.

Equipment was proposed as:

Telefunken FuG 220 ‘Lichtenstein’ SN-2 D A/I set (later to be replaced by Siemens FuG 218 ‘Neptun’)

Telefunken FuG 350 ‘Naxos’ passive radar to home on to emissions of Allied bombers.

• Was it a good solution to max power with minimum wetted area (compared to, say, the Hornet)?

I’m afraid I cannot comment with regard to the Hornet, which is beyond my knowledge, but it’s an interesting question! Powered by two Daimler-Benz DB 603 engines (one each in the nose and rear fuselage), the Do 335 had, for example, a maximum speed of 732 km/h at 7.1 km. It took 14.5 minutes to climb to 8,000 m.

• Did pilots like flying it? What did they like about it?

The Luftwaffe never flew the Do 335 operationally, although a test unit, Erprobungskommando 335, was established in late 1944. The small group of Luftwaffe pilots who conducted test flights felt the Do 335 could best be deployed as a night fighter.

A test pilot at the Luftwaffe test centre at Rechlin, Flieger-Haupting. Hans-Werner Lerche, summarised: ‘The Do 335 was an unusually powerful aircraft with exceptional flying qualities, and an aeroplane that bestowed on me the pure pleasure of flying, a feeling which I shall not forget as long as I live.’

Lt Cdr Eric Brown, test pilot attached to the Aerodynamics Flight of the Experimental Flying Detachment, recorded: ‘I found the Do 335 lively to fly, and right from the short take-off run under the smooth roar of the two Daimler-Benz DB 603s, it afforded that comforting feeling of being over-powered, a gratifying sensation that one seldom experiences… View in the air was excellent and I had a distinct feeling that the Do 335 was better suited to nocturnal than diurnal fighting…’

• What was its best feature?

Its ambitious experimentalism.

• And worst?

Its ambitious experimentalism. Paradoxically, its design did not live up to the aircraft’s name of ‘Pfeil’ – ‘Arrow’.

How would you rate it in the following:

Sustained turn

Instantaneous turn

Climb rate

Speed

Acceleration

I believe all above were acceptable for 1944, but they would be exceeded and or outclassed by the new German jet types.

Take-off and landing characteristics

These were the two areas where the Do 335 would have probably bettered the jets.

Cockpit layout

Well laid out, and roomy with good vision when airborne, but because of the aircraft’s height when on the ground, tricky when taxiing.

• How much fighting did it do?

None.

• What is the most interesting fact about its development?

Possibly that such a monstrous (and expensive) aeroplane was seen to have multi-role capability: day and night fighter, ‘Zerstörer’ (‘heavy’) fighter, long-range reconnaissance machine, bomber, all-weather aircraft.

• Describe it in three words

Ambitious. Clever. Complex.

What is the greatest myth about the 335?

It was unimportant

What should I have asked you?

About the planned Ju 635 Zwilling (twin-fuselage) long-range maritime reconnaissance aircraft – now that would have been monstrous!