On 12th October Ralph Denning
came up from Bristol, with Gordon Lewis, to talk to the Association
about wartime German aeronautical research and development and its
effects on post-war aviation.
Ralph joined Bristol Engines in 1949 and stayed with them for 39 years,
20 years of which he spent as Chief Engineer Future Projects, having a
major influence on powerplants for many types including Harrier and
Concorde. Before joining Bristols he was with the Ministry of Aircraft
Production (MAP) and during 1945-1947 was in Germany with the UK team
assessing German wartime R&D.
The team was amazed by what they found; extensive wind tunnel
facilities for low and high Mach number work, innovative aircraft
designs and engine types, air-to-surface, surface-to-air, air-to-air
and intercontinental missile projects. Clearly the end of the war had
come just in time before these new aircraft and weapons could be
brought to the operational stage. The allies had put their efforts into
fully developing what were really obsolescent types rather than looking
to the future, so, had the war dragged on, they were in danger of being
seriously outclassed.
SETTING THE
AGENDA FOR AEROSPACE
In
Germany academic institutes had always had a powerful influence on
design and major research establishments staffed by expert scientists
had been set up throughout the country. For example, the DVL in Berlin
had a 9 ft wind tunnel, the AVA at Gottingen 2 tunnels, the LFA at
Volkenrode 6 tunnels, ballistic tunnels and a high altitude engine
testing facility, the LFM at Munich a 9 sq ft tunnel, at St Ozal in the
Italian Alps a sonic 26 ft tunnel was under construction and at Kochel
in Bavaria 3 missile research tunnels for Mach 3.3, 4.4 and 10 were
operational!
Ralph was mainly concerned with the Herman Goering Aeronautical
Research Institute, LFA, at Volkenrode, near Brunswick, which was
overrun by the US 9th Army in April 1945 and by July the MAP's
'Operation Surgeon', led by Roy Fedden, was under way. The facilities
were hidden in 1,100 acres of woods with no visible roads, railways or
power lines so, although recce. photographs had been taken, its
importance was not recognised.
Under Prof. Herman Blank the LFA had three divisions: 'A' for
aerodynamics and structures, 'M' for engines and rockets, 'W' for
weapons and ballistics. Working in 'A' was Dr A Busemann who at the
1935 Volta Congress had, unnoticed, given his paper on the significance
of wing sweep. Boeing's Chief Aerodynamicist, George Schairer, visited
the LFA in May and reported Buseman's work on sweepback, which led to
the B-47. The NACA also quickly responded to this information with
dropped body tests on swept wings demonstrating 30% drag reduction at
Mach 1. However, the UK was slow to react.
The 'A' division had six advanced wind tunnels. A1 was a 2.5m low speed
tunnel. Under test was an Arado swept crescent wing with underwing
podded engines. This layout was also reported by Schairer and the wing
planform was adopted by Handley Page. A2 was a 2.8m high speed
(.82-.90M) closed return tunnel that could be run open for engine
testing. The huge A3 8m low speed return tunnel consumed 15,000 hp. The
A6 and A7 pair of high speed intermittent suck- and blow-down tunnels
with a 1,000 cu m reservoir operated at .94M and Mach 2 to 4
respectively. The A9a open working section closed circuit .93M tunnel
could also be used open return for jet engine and ramjet testing. The
A9b closed working section 1.6M tunnel used two 4,500 kw motors which
were taken to RAE Bedford for their 3 ft supersonic tunnel.
The LFA 'M' Institute was an engine development and test facility
including an altitude testing chamber and combustion test rigs in the
woods. Under test were the BMW 003 and Jumo 004 axial flow jet engines.
The latter, of which prototype construction started in 1939, powered
the Me262 twin jet fighter and the Ar234 high altitude reconnaissance
bomber. Also in evidence was a gas turbine powered Panther tank.
The 'W' Weapons Institute was housed in dummy farm buildings with
underground ballistics tunnels, including the 400m W1, and rocket
research facilities. Nineteen guided missile projects were initiated in
Germany, of which four became operational: the Ruhrstal SO 1400 radio
controlled 'smart' bomb, the Henschel Hs 293 rocket propelled
air-surface missile, the V-1 pulse jet propelled flying bomb, and the
V-2 rocket propelled ballistic missile. There were 8 air-air weapons of
which 2 were nearly operational, and the A9/A10 two stage ICBM project,
a winged V-2 with a booster, to attack the USA. The Enzian SAM, based
on the Me163 rocket fighter was in production but was stopped by allied
bombing.
There were several operational jet aircraft types, the most successful
being the Me 262 which originated from a 1938 (!) requirement, flew in
1942 and, after a year's delay for work on a fighter-bomber version,
was in service in 1944 (1,433 built). The specification for the wooden
Heinkel He 162 was issued in June 1944, the prototype flew in December
and the first of 100 production aircraft was delivered in March 1945.
The twin jet Arado Ar 234 was operational in 1944 and the four jet
Junkers Ju 287 bomber was flying as a prototype in 1944. This aircraft
had forward swept wings and was designed using the area rule principle.
Ralph showed a slide outlining the scope of German work on
swept wings with 52 jet projects illustrated, several of which had
reached the prototype stage with a few in production. Layouts included
tailed and tail-less swept back, swept forward, delta, 'W', slewed,
twin boom, with podded and buried engines. Particularly significant was
the Jumo 004 powered Messerschmitt P.1101 with ground adjustable
variable sweep wings and a 'pod and boom' fuselage. The incomplete
prototype was taken to the USA where the Bell X-5 research aircraft was
closely based on the Messerschmitt design but incorporated in-flight
variable sweep. The 'pod and boom' layout was also adopted in the swept
wing SAAB J-29 and the Yak-15 whilst German swept wing technology was
capitalised on by North American in their F-86 Sabre and by Mikoyan in
the MiG-15.
After the war several German scientists worked at RAE Farnborough
including Drs Busemann and Kucheman, the latter developing wing
planforms for Concorde utilising the work of the German delta pioneer,
Dr Lippisch. Lippisch's work also influenced the design of the Vulcan.
In conclusion Ralph listed the technologies taken to a high level by
Germany during the war: high speed aerodynamics, gas dynamics, rocket
propulsion, axial flow gas turbines, ramjets, pulse jets and guided
weapons.
Applications included swept and delta winged jet aircraft,
cruise missiles, strategic rockets, guided bombs, air-to-surface and
air-to-air guided missiles.
After question time Ralph Hooper gave the vote of thanks quoting Sydney
Camm, on seeing the design of the swept wing Messerschmitt P.1101, as
saying "Did you ever see anything so bloody useless?" His first swept
wing aircraft, the P.1052, did not fly until November 1948 although
Hawkers' first swept wing project, the P.1047, was drawn by Vivian
Stanbury in 1945.