Sunday, 7 February 2016

Arado Ar234.The Development of the Blitz - versions B and C. Part 2.

Text found in the internet.

"This document with excerpts from several books has been created under ‘fair use’ copyright as background information for trips to Alt Lönnewitz and Rheine that we made in 2015 as part of a study project. All copyrights remain with the copyright holders named in the references. If you wish to use copyrighted material from this document for purposes of your own that go beyond ‘fair use’, you must obtain permission from the copyright owners."

Arado 234B

The first prototype of the Ar 234B variant (Ar 234 V9), that had been ordered on 9th February 1943, was completed in early March 1944. The expected bomb payload was maximum 1,500 kg. Additional rocket boosters, mounted under wings, were necessary for a loaded take-off. Alternatively, two auxiliary 300-leter drop tanks could be carried under the engine nacelles. The first flight of the Ar 234 V9, from Brandenburg to Alt Lönnewitz by captain Janssen, took place on 12th March 1944. During the next two test flights, conducted on 15th March 1944, Janssen experienced problems retracting the flaps after take-off. This issue was partially solved by re-building the flap retraction mechanism. On 21th March 1944, Siegfried Knemeyer carried out a 17-minute test flight of the Ar 234 V9. In the period between 17th - 20th April 1944 at Alt Lönnewitz, tests were conducted with bomb armament. On 29th April 1944, Knemeyer performed a 30-minute demonstration flight over Oranienburg airbase for the Wehrmacht and some RLM officials.
Arado 234 V9

Arado 234 V9

On 7th April 1944 was the first flight of the Ar 234 V10 prototype by Janssen. This machine was the first to be equipped with an RF2B periscope, which gave the pilot some vision to the rear.
On 9th May 1944 the first formation flight took place by two Ar 234s, the V9 flown by Eheim and the V10 flown by Janssen. It was concluded that there had to be at least a 1.5 minute interval between such take-offs due to the smoke produced by the rocket boosters, which limited visibility. A simultaneous take-off of two machines from a 60-meter wide runway was not possible. This led to the conclusion that if ten aircraft were to take-off from the same airfield, the last one would have to wait a quarter of an hour for its turn.
Arado 234 V9 (WNr. 130 009) was the first prototype of the Ar 234B-2 version
Arado 234 V9 with auxiliary rocket boosters under its wings
In late May 1944 the V10 prototype was equipped with a Patin PDS-11 autopilot. The Patin factory pilot Hans Richter tested the autopilot.
At Mid-June 1944, the Ar 234 V10 prototype was presented at Rechlin to Erhard Milch and Albert Speer. A mock dogfight between the Ar 234 and the Me 262 was organised, during which the Ar 234 showed its superior manoeuvrability.
On 27th June 1944 an extraordinary incident occured as the Ar 234 V10 was being flown on its 50th flight by the Patin factory pilot Hans Richter. A strong vibration developed in the port engine. The pilot switched it off, but its temperature, according to a gauge reading, was still increasing. Richter was convinced the engine was on fire and decided to bail out. The machine, controlled by the autopilot, flew around in two wide circles over the airfield, after which it landed smoothly in a nearby field. Exhaust gases from the still-running starboard engine set the surrounding cornfield on fire, and before the airfield fire brigade could reach the spot, flames had destroyed the Ar 234 V10. An investigation of the wreckage established that the engine vibration had been caused by a torn-off turbine blade, which had damaged the temperature sensor.
The third prototype of the Ar 234B, Ar 234 V11, made its first flight on 10th May 1944 from Brandenburg to Alt Lönnewitz, and was tested there the following days for high-speed and high-altitude tests. The last prototype of the Ar 234B was the Ar 234 V12, and was first flown on 15th September 1944. In order to improve directional stability the aircraft was fitted with an enlarged tailfin and rudder. This type of vertical stabilizer was to be used as standard on the Ar 234C variant. Two basic variants of the Ar 234B were planned, the B-1 reconaissance variant and the B-2 bomber variant, but the Ar 234B-1 did not enter series production.
After production of the reconaissance variant was cancelled, provision was made in the Ar 234B-2's rear fuselage for the installation of one or two camera's. The Ar 234B-2 could perform shallow angle dive-bombing and level bombing at both high and low altitude. The first pre-production machines of the B-2 variant were designated S1 through S20. The S-series were used for testing various pieces of equipment. The Ar 234 S1, which was first flown on 8th June 1944, was lost in a fatal crash at Lärz on 25th June 1944. Some machines from the pre-production series were lated passed to operational units. Overall, there were 20 pre-production aircraft and 186 series-production Ar 234B-2s manufactured.

Arado 234C

In the summer of 1943 the Arado engineering team decided to mount BMW 003 engines on the Arado 234 in place of Jumo 004s. The former were both smaller and lighter. However, in order to achieve sufficient thrust for the aircraft, four BMW engines had to be mounted under the Ar 234's wings.
Two concepts were considered. In the first concept four separate engine nacelles were to be installed. In order to test this concept, the Ar 234 V6 prototype was rebuilt to accommodate two more engine mountings. In the second concept two pairs of twin-engined gondolas were to be installed. For this concept a designated prototype was ordered, the Ar 234 V8.
Arado Ar 234 V6 (WNr. 130 006) equipped with four BMW 003A-0 engines in separate nacelles
Ar 234 V6 at Alt Lönnewitz
On 25th April 1944 Janssen flew the Ar 234 V6. Again, the BMW engines proved very unreliable, while drag that was produced by the spluttering of the outboard engines made it difficult to maintain control over the aircraft. During its seventh flight on 1st June 1944, Janssen made an emergency landing in a field due to engine problems. After landing the only running and overloaded engine caught fire, damaging the plane so that it was written off.

Moving the Ar 234 V6 to the runway

Arado Ar 234 V6 after crash landing on 1st June 1944
The Ar 234 V8 was the first to fly on 4th February 1944, with Janssen at the controls. It was the first four-engined jet aircraft in the history of aviation. The V8 prototype completed six flights, during which many problems were encountered with the engines. The last flight of the V8 took place on 6th May 1944.
Arado Ar 234 V8
Arado Ar 234 V8 (WNr. 130 008) equipped with four BMW 003A-0 engines in twin-engined gondolas
Over some time the quality of the BMW 003 engines were improved, and after evaluating the two four engined test machines, it was concluded that only the V8 variant with the double-engined gondolas was satisfactory.
Further testing of the BMW engines was carried out by the Ar 234 V15 and the Ar 234 V17 prototypes, which were fitted with two BMW 003 engines. The V15 was first test-flown on 20th Junly 1944, and the V17 on 4th October 1944, both times by Janssen. Following testing until January 1945, the aircraft were passed to an operation unit.
Arado Ar 234 V17
Arado Ar 234 V17 (WNr. 130 027) equipped with two BMW 003 engines and auxiliary rocket boosters
On 6th September 1944 Janssen test-flew the Ar 234 V13 prototype, equipped with four BMW 003A-0 engines grouped in two double units mounted under the wings. Due to engine problems Janssen had to make an emergency landing, and the aircraft was written off.

In March 1944 the Arado design bureau proposed two basic variants of the planned Ar 234C series. The first variant, designated Ar 234C-1, was to be a reconnaissance variant equiped with two cameras mounted in the rear fuselage. The second variant, designated Ar 234C-2, was to be a bomber with a maximum payload of 1500 kg. On 16th May 1944 the RLM representatives were shown a wooden mock-up of the future Ar 234C. The project was approved, although some changes to the cockpit and canopy area were recommended.
Arado proposed two new variants, one fitted with a pressurized cockpit. The new bomber variant was designated Ar 234C-3. The first prototype of the Ar 234C-3 was the Ar 234 V19. It was first flown on 16th October 1944 by Janssen and tested until January 1945. The tests were generally successful, but strong vibration of the rear fuselage at high speeds was a serious problem.
Arado Ar 234 V19 (WNr. 130 029) of the Ar 234C variant powered by four BMW 003A engines
The second prototype of the Ar 234C-3 was the Ar 234 V20 with a pressurized cockpit, first flown on 5th November 1944. Three days later a Focke-Wulf Fw 190 wrecked it. The remaining C-3 prototypes were version V21 to V25. The cockpit was redesigned to improve visibility, it had two rearward-firing MG 151/20 cannons, and two nose MG 151/20 cannons. It could also carry a variety of bombs on ETC 504 bomb racks."

References


  • Arado: Geschichte eines Flugzeugwerks; author Jörg Armin Kranzhoff
  • German Aircraft Industry and Production 1933 - 1945; authors Ferenc A. Vajda, Peter Dancey
  • Aircraft Profile No. 215: Arado 234 Blitz; author Richard P. Bateson
  • Arado 234 Blitz (vol I & II); authors Marek J. Murawski, Marek Rys
  • Blitz!: Germany's Arado Ar 234 Jet Bomber; authors J. Richard Smith, Eddie J. Creek
  • American Raiders; author Wolfgang W.E. Samuel
  • airandspace.si.edu
  • wikipedia.org"