By contrast the Argus
company was making good progress with its pulsejet
development and made the first pulsejet flight test
earlier in 1941. This contrast in success between
the intransient turbojet and the mechanically simple
pulsejet must have lead to some overenthousiasm for the
latter when, in January 1942, the He 280 V1 made its
ill-starred and only flight under the power of four Argus
109-014 pulsejets.
1.Exhaust nozzle, 2.Valve control,
3.Fuel and air lines. 4.Orifice,
5.Inlet-diffusor, 6.Trunnion,
7.Spark plug.
The shutter controller of the Argus 014 engine
showing the flat spring valves and injectors.
Ramjet
Mechanically even more simple, the ramjet was receiving
only scant official attention from the RLM (Reichsluftfahrtministerium) althoug
Otto Pabst (at Focke-Wulf), Eugene Sänger and
others had by 1941 followed Walter’s lead in
experiments to develop an aircraft ramjet. Trommsdorf,
on the other hand, had full backing from the Army for
development of ramjet-accelerated artillery missiles
(which were reaching full succes in 1943).
A Do 217E-2 employed to test a Säger ramjet with a 39.37-in. diameter
combustion chamber during the summer of 1944.
Thirty-two flight tests were conducted with
this unit.
Junkers 109–004
The first flight test of Junkers 109–004 turbojet were
made in March 1942, in which month two P.3302 engines
powered the Me 262 V1 (see previous page). At this time,
the BMW engine was only giving some 550 kp (1213 lb)
thrust while the Junkers engine was giving 600 kp
(1323 lb) or more. The less-advanced Junkers engine did,
in fact, initially overhaul the BMW engine and two
Junkers 109–004A turbojets powered the
ME 262 V3
for the fighter’s first all-jet flight on July 18, 1942.
Me 262 V3 was fitted with extended wing leading edges between
the fusulage and engines. Adolf Galland was
particularly enthused with the design after
flying it on 22 May 1943.
Me 262 V3 taking off on July 18, 1942
Fi 103, WNF 342, Ar 234
Another first flight occured the following December when
the first Fi 103 (V1) flying bomb was test launced with an
Argus pulsejet.
Possibly the best-preserved Fi 103 (V1) flying bomb, now in Canada.
(National Aeronautical Collection – Ottawa).
An He 111 H-6 modified to carry a single
FZG 76 (V1) missile under
the port wing.
New programmes instituted in 1942
inlcuded work on a 8.000 eshp turboprop engine at BMW
and a research project for a jet helicopter under
Doblhoff at WNF, Vienna. The prototype of this, the
world’s first jet helicopter, the WNF 342, flew
in the spring of 1943 and utilised compressed air and
fuel burning in rotor-tip chambers to power its rotor.
The Doblhoff WNF 342.
By January 1943, pre-production Junkers 109–004B turbojets
were ready and two of these were used in June to power
the prototype of the world’s firt jet bomber, the
Ar 234 V1. The
Arado Ar 234 V1 flew for the first time
on June 15, 1943 with flight-cleared Junkers Jumo 004A
engines.
The Ar 234 V1 on its take-off trolly.
The Ar 234 V1 taking-off on its initial flight.
Me 328, He 280
The year 1943 also saw the first pulsejet-powered
fighter (the Me 328) tested and, in August, the first
pure jet flights with BMW 109–003 turbojest
(using the He 280 V4).
One of the initial pre-production Me 328s used for gliding trials.
Me 328 on take-off dolly with pulse jets fitted.
Long before this, the Heinkel He 280 had lost the
competition contract, briefly on the grounds that the
He 280 was short on range. From the start, an over
optimistic estimate of the fuel consumption of Heinkel
turbojets had led to internal fuel tanks of insufficient
capacity.
Me 262, Ar 234, He 162
During 1944, the first pre-production
Me 262 A-0 fighters and Ar 234 B-0 bombers began tests,
experimental sorties and, finally, full operations. Most
of these used the Junkers 109–004 turbojet since the
BMW 109–003 turbojet was earmarked chiefly for the
Heinkel He 162 Volksjäger fighter.
He 162 V1 simplified
fighter plane, powered by
the BMW 003 A-1 engine. Only 74 days elapsed
from the time the contract was awarded to the
airplane’s maiden flight. Below
He-162 V6
23 january 1945.
Future development
Apart from the Junkers 109–004 and BMW 109–003
turbojet engines, which were ready for operational aircraft
by the end of the war, there were a great number of projects
and developments in every stage. To finalize, the status
of some of this work can be mentioned.
The class II Heinkel-Hirth 109–011 turbojet, though being
readied for mass-production, was not fully developed and a
tuboprop derivative of this engine (the 109–021) was
turned over to Daimler-Benz in May 1944 when that company
abandoned its complicated 109–007 turbojet.
DB 109–007 dual-flow turbojet engine
with counter-rotating axial compressors
was ready for static testing in 1943.
Uder the designation DB 109–021, Daimler Benz
continued with the development of the HeS 021
turboprop which it had aquired from Heinkel-Hirth
Triebwerkbau. The engine was claimed to have
an output of 2000 hp and a standing thrust of
790 kp.
The P.1101 experimental design used for experimenting
with wing sweep angles, fitted with a HeS 011 turbojet.
After the war ten HeS 011 V4, capable of producing
1300 kp of thrust, were built at the insistence of
the Americans and sent to the USA and England for
studies.
Drawing of the HeS 011.
Other
class II turbojets such as the Junkers 109–012 and
BMW 109–018, together with their turboporp derivatives,
saw less headway than the Heinkel-Hirth effort.
BMW 018, designed for 3500 kp thrust, was finished
and ready for static testing when it was
destroyed in a bombing raid in 1945.
During 1944,
the official priority was raised for development of aircraft
ramjets (though only Sänger ramjets were actually flown
using test beds) and also of expandable turbojet missiles.
The BMW and Porsche companies made a start in the latter
field. In the hybrid jet engine field, most headway was
made with BMW’s 109–003 R turbojet/rocket unit
which was tested by an Me 262 in March 1945.
The BMW 003 R is a combination of a BMW 003 A and a BMW 718 rocket engine,
with a thrust ouput totalling 1800 kp.
Another development was the Me 262C-1a
(Werk-Nr. 130 186) Heimatschützer I which had a rocket moter (R II-211/3) mounted in the
rear fuselage. It could attain an altitude of 11.704 meters from a standing
start in 4,5 min.
