Messerschmitt Me
155B DB628 engine high altitude. The boss is on the nose is where the
turbocharger TK 11 was installed.
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Messerschmitt Me 155B -1 with complex DB 632 engine with propellers contrarotativs |
In order to
relieve the burden on the already overburdened design office and to accelerate
the development, Messerschmitt decided to transfer the Me155B to Paris. Due to
various problems work progressed slowly during the rest of 1942. In early 1943
things start to go wrong with the project, while the Focke-Wulf moved well with
Ta 152, little had been achieved with the Me 155B. During the first half of
1943, Messerschmitt´s design engineers had evolved over the basic design
parameters of a fighter of extreme altitude, under the name of the company as I
P1091. In mid-1943 Messerschmitt staff was hesitant as always continuing to
build the Me 209H to compete with the Ta 152H and turning the project P1091 as
Me Me 155B.
Three views of the P.1091 project with two different stages or Stuffe |
Messerschmitt
project called P.1091 Stuffe III, which consisted to use the DB603 engine with
turbocharger TKL 15 or DB632 complex engine and propellers contrarotativ
maintaining long fuselage.
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Contrary to what
was thought at Blohm & Voss, Messerschmitt had done very little work on Me
P1091. In the coming weeks the team of Blohm & Voss began to discover this
deficiency by themselves. The engineers at Blohm & Voss were not impressed
with the Messerschmitt´s drawings, and it was just a matter of how much had to
be changed. It soon became apparent that almost all Me 155B systems including
wings, fuselage, rudder, turbosupercharger housing and landing gear, were inadequate.
In September 1943 the construction of five prototypes was decided, however soon
after, Blohm & Voss decided that design problems should be corrected. In
late 1943 these had not yet been fixed. At a meeting of high importance to
address these problems, Messerschmitt´s responsibles did not attend it. The
meeting was finally held, but with little to show despite all the effort. Later
Blohm & Voss was also asked for more workers to put project in motion. By
November 1943 they were still making changes to design and equipping of weapons.
Another change that Blohm & Voss was being contemplated was leaving the
complex series of eight from the beginning and then four radiators located on
the underside of the wings that Messerschmitt supported, for two large scoop
type units mounted above the wings. A model of the design was built and tested
in the wind tunnel LFA, but this time, everyone in Blohm & Voss was fed
with the lack of cooperation from Messerschmitt. In late 1943 Blohm & Voss
officially informed to RLM of their problems with Messerschmitt and implored
them to intervene.
Three views of the Me 155B -1 with the complex system with 8 radiators |
The BV 155A. Radiators still held above the wings which had been designed by Messerschmitt engineers |
With the official
transfer of the Me 155B to the Blohm & Voss, the aircraft designation was
changed to the BV 155A. Finally freed from the limitations imposed by
Messerschmitt, Blohm & Voss immediately points to reassess the new fighter.
After a thorough critical examination of the BV 155A, engineers at Blohm &
Voss concluded that it would be less expensive and more reasonable to leave
this design and take directly the BV 155B. In the meantime he had changed. The
most obvious feature of the B series was the re-positioning of the two large
radiators which went from being up to be below the wings. This was done to
achieve better stability and to improve air flow units. The starboard radiator
used to cool the engine lubricants, while the port is used to cool the heat
exchanger oil cooler to post cooler (aftercooler) and to cool the air before
entering the turbocharger (intercooler ). In the spring of 1944, all major
systems are designed, the issue of engine and armament resolved and plans were
made to immediately begin construction of the first five prototypes.
In mid-1944 it
was proposed that the 5 prototypes BV 155 be completed by the middle of 1945.
Meanwhile, Blohm & Voss had been working on the BV P205, this had a
different design than BV 155B originally designed to be equipped with an engine
Argus As 413 24-cylinder 4000 hp, water cooled. Due to the unavailability of
this engine, Bv P205 in its final form, was powered by the DB603U. In the BV
P205 were eliminated two wing-mounted radiators, the size was reduced and the
space between the wheels of the landing gear was lowered. A ring radiator
incorporated in the nose, while two moderately large air intakes for the
radiator on both sides of the fuselage were placed near the cockpit. Clearly
Blohm & Voss thought that Bv P205 had potential, reducing the number of
radiators and change the engine cooling system could save weight and reduce
drag. This new aircraft design was approved and received the designation of BV
155C. There was now a need to build prototypes, the prototypes of V1 to V3
corresponded with the B series aircraft, while V4 to V7 prototypes corresponded
with C. The first prototype version Bv 155B was hoped for December 1944. Then
later Blohm & Voss and the RLM decided to build only two prototypes BV 155B
and then directly go to the series C. In early August 1944 the mock-up was
completed and ready for inspection, and this successfully completed
construction of the first prototypes was pushed as quickly as possible.
Blohm und
Voss P.205 project.
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P. 205
Illustrative image in flight and the applied cammo.
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In September 1944
a revised timetable had Bv 155B V1 ready by December 1944 and the V2 ready to
January 1945, while the number of series C preproduction aircraft rose to 30.
In October 1944, the BV 155B was reclassified as "escort fighter"
this was possibly because at this stage there was a massive reevaluation of all
aircraft in production in the German manufacturing indiustry reducing or
canceling orders. During this period the V1 and V2 prototypes were nearing
completion, with full V1 prototype just before Christmas 1944. After several
tests of vibration, the first flight was scheduled for mid-January 1945. At
this stage yet it is carrying out work on finalizing the design for the Bv
155C. Meanwhile, the BV 155 V2 was halfway to being completed, while the BV 155
V3 was only 30% full. In early January 1945, meetings were held in an effort to
determine how and where the production of the BV 155 could be decentralized. It
was proposed that the Focke-WuIf and Dornier were involved. However, both
manufacturers strongly committed to their own programs and placed little hope
in entering production line until at least March 1945. Finally, on Monday,
February 5, 1945, the BV 155 V1, W.Nr . 360051, was delivered to Blohm &
Voss flight section.
Three views and
drawing as had been the BV 155B - 1 with cammo applied
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Meanwhile the Blohm & Voss officials
decided to end all further work on the incomplete BV 155 V3 and concentrate all
efforts towards the completion of the first prototype of the C series, the BV
155 V4. At the time, it was moment for the maiden flight of the BV 155B V1
which was held on February 8, 1945. This first flight was cut short by coolant
leakage, but fortunately the BV 155B landed without further incident. Working
against time, the necessary repairs were made and the modifications were
completed on February 10, 1945, a second flight was conducted, this time
without repeating coolant leaks. However, the test pilot said that the takeoff
was difficult due to the muddy conditions of the grass field. This was the
result of rainfall in the past two days. It was also noted that the aircraft
had a wide distance between the main landing gear (6702mm) which was the main
reason for the tendency of the aircraft to make a loop, even during soft
landings. There was also a problem with the main gates of the wheel as they do
not close properly, there was a potentially serious problem as it could block
the flow of air through the radiators mounted on the wing. Low clouds also
prevented the high speeds that were planned for this flight were developed,
only a top speed of 218 mph was reached while landing approach speed was
modest: 106 mph. After the second test flight, the BV 155 V1 returned to the
hangar 2 where he underwent additional work to correct the problems. In the
next two weeks plans were made to conduct flight tests with special measuring
equipment carried on board and operated by the pilot. It was scheduled to fit a
semiautomatic camera to record certain flight conditions. A total of forty
tables have been provided with what is expected that much additional flight
information could be recorded. Then, on February 20, 1945, a secret directive
from OKL based in Berlin came to the Blohm & Voss P212 warning that the BV
155 and BV had been included in the current emergency program. February 21,
1945, was a busy day for the engineered Flight of Blohm & Voss as they
rushed to complete vibration test system lubricants motor BV 155 V1 in anticipation
of the upcoming tests of flight. This was on 26 February 1945. With the gross
weight of 5900kg apparatus in the third off the BV 155 V1 was flawless, despite
the very soft condition of the field. The pilot had no difficulty keeping the
aircraft on course meanwhile accelerated and left the track. As in the two
previous flights, the short take-off was impressive. After taking off again
there were problems with the doors of the main landing gear as they do not
close properly, possibly in the third attempt the doors are completely closed
but in the process there was additional damage to these doors.
Fortunately, refrigeration temperatures
remained constant between 225 and 230 degrees F (107 ~ 110 ° C), which were
within the permissible limits. This third test flight was relatively smooth,
but post-flight inspection revealed that there had been another leak of liquid
in the drain tank, a crack in the wing near the wing welding and the landing
gear doors. With the arrival of March 1945, Blohm & Voss staff was busy
making repairs and modifications to the BV 155 V1 while moving toward the
conclusion of the BV 155 V2. In Blohm & Voss on March 7, 1945, it was
decided that the BV 155 V1 would have at least 10 hours of flight in March and
15 hours in April, with the most flights carried out to astonishing height
ranging from 45,933 and 52,493 feet (14-16 km). It was also envisaged that the
BV 155 V2, W.Nr. 360052, is finished and ready to fly in March, with a maximum
of 10 hours of flights scheduled test to April 1945. In the coming months work
will be continued in the second prototype, while performing repairs and minor
modifications in the first prototype. With so many unresolved problems
associated with the fourth prototype, the first machine of the C series, there
was little progress toward building and only a few elements were built. No
other survivors record test flights carried out with the first prototype before
the arrival of the British. It is very doubtful to be made some more. On May 3,
1945, the city of Hamburg surrendered to the British.
All
the German staff was ordered to leave Blohm & Voss facilities without
exception. Throughout the month of May no German was not allowed into the
forbidden zone. British authorities were very interested in the aircraft and the
facilities found in Blohm & Voss plant. The British lost no time in
declaring things were going to be sent to Britain for examination. Opening
doors to Hangar 2 they were found with the BV 155 V1 and immediately made plans
to transfer the prototype to England. In Hangar 1 who he discovered the still
incomplete BV 155 V2, while the BV 155 V3 prototype was quickly located outside
Hangar 1.
Scale mockup of the unique wood build
prototype BV 155C-0 (partly)
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Determining what happened to the three
prototypes BV 155, once fell into British hands is very complex and has led to
much confusion. It seems that the BV 155BV1 was airworthy when captured. He was
tested by the British after applying logos and serial number PN820? Apparently,
the British pilot experienced flight failure forced him to make an emergency
landing. In the forced landing the prototype was damaged and the
decommissioning. The exact nature of the accident remains unknown. But in any
case, the British were deprived of the only example of the BV 155B airworthy.
British then quickly collected all components of the BV 155 V2 incomplete and
were sent Royal Aircraft Establishment (RAE) in Farmborough, to be displayed
during the exhibition of German planes captured conducted in late October and
running until November 9, 1945.
One of the few pictures of BV 155 B only
survivor in Silverhill in 1973 (USA).
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The second armed but still incomplete
prototype was put on display for the public inside the building "A".
The incomplete third prototype, which meanwhile was also sent to RAE
Farmborough, was transferred to MU No. 47, where he was prepared to be sent to
the United States. It was thought to complete the second prototype and test it
but like other projects at the end of the war were canceled due to lack of
budget. Later the third prototype sailed to the United States where he was
given the designation FE-505. It was then stored at Wright Field's Air
Technical Services Command for several years. It gives then the T2-505 code and
stores it indefinitely in the National Air and Space Museum's Paul E. Garber in
the Installation Restoration in Silver Hill, Maryland.
The Blohm und Voss Bv 155C was a different design than the P.205, possessing a rectangular air intake below the engine and lacking the large air intakes for the radiator on both sides of the fuselage which were placed near the cockpit of the P.205 project. The Monogram Aviation book on the Bv 155 by Thomas Hitchcock published in 1990 and a 2019 book by Dan Sharp regarding the Bv 155 can be consulted for details regarding salient differences between the P.205 and Bv 155C.
ReplyDeleteLinks:
https://epdf.pub/blohm-amp-voss-155-monogram-close-up-20.html
https://www.amazon.com/Secret-Projects-Luftwaffe-Blohm-Close/dp/1911658328