BV-155

The Bv-155 was built as i high altitude fighter/interceptor in parallel with the Ta-152, developed by Kurt tank. The Bv-155 barely made enough flights be noteable, while the Ta-152 went into production and service, and saw some action. The delay for the Bv-155 was in most part due to the Messerschmidt company, who lagged behind on the design. They were developing the aircraft with the Blohm und voss company, but Messerschmitt wasnt keeping up its end of the bargain, not supplying the proper amount of workers, supplies for the program, and unwilling to change the overwing air intakes that would cause problems. Finally the Bv-155 was handed over fully to the Blohm und voss company, and real work began. The desing was thoroughly looked over and examined, moving the air intakes to under wing positions, eliminating the intake problems. Finally a BV-155B model flew, in prototype form, but suffered from leakage problems, quickly corrected, cracked wing spars, and the main problem was the landing gear doors had trouble closing. Then the luftwaffe ordered that the BV-155C model be produced, much higher numbers of prototypes and evaluation models that the B series. However none were completed. The B model that flew, never reached its full speed, and held it for more than a short period, but the test flights were scheduled to be between 49,250ft and 55,000ft!!! Amazing, something i dont think many aircraft at the time could do, much less carrying cannon, including Mk-108 and Mg151/20's. What are your opions on the potential of the possibly remarkable aircraft?

The desing was thoroughly looked over and examined, moving the air intakes to under wing positions, eliminating the intake problems.

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The air intake for the TKL 15 turbocharger was under the fuselage, slightly behind the wing's trailing edge. What was under the wings was the coolant radiators.

The Mtt initial Me155B design had 2 underwing radiators also. They were simular to those on the 109. The Me155B-1 design 8 radiators under the wing with the a/c retracting into posd at mid span.

http://www.samoloty.ow.pl/str404.htm

There was no trouble with the landing gear doors closing. Just before the wheels went into their wells they blanked the radiators causing some overheating. During a test flight on Feb 26 Rodig could not get retraction switch to operate the gear. Another throwof the switch and the landing gear began to retract but the port door closed to soon and was damaged. Rodrig threw the switch again and the gear retracted correctly but further damage was done to the doors.

The a/c was to have MK103 and MG151/20 cannons. No MK108s.

As most bombers (including the B-29), flew to their targets at around 24-27,000 feet, the test flight schedule altitudes seem a little silly. As with the TA-152C, there is really no need for that much performance at that kind of altitude. Its almost as if they wanted performance at altiude simply for the sake of it. There is nothing to intercept or escort above about 33,000 feet.

The LuftWaffe would of been better-off if it had concentrated on aircraft that produced their best speeds at about 27,000-33,000 feet, right in the zone to dive in on bomber formations and escorts and then run away. If combat was important I'd rather be flying an aircraft capable of 430-450 mph at 30,000 feet, than one that can fly at 450 mph at 49,000 feet.

The BV-155C was destined to get the DB-603U, a specialised high-altitude variant of the excellent DB603, fitted with a turbosupercharger, specialised intakes and a more effective annular radiator. While there were a few B serise test flights in very late 1944 and early 1945, the C serise never got off the ground. Esatimated speeds with the 603U were 650 kph at 12,000 m (404 mph at 39,400 feet) and 690 kph at 16,000 m (430 mph at 52,500 feet).

Going off these figures the Ta-152 woulbs seem to have better performance. Besides that, it was actually in limited production, whereas the BV-155 was months away from seeing any service.


Hypothetically, if the Allies need a counter, fitting the Spitfire VIII airframe with 100 series Merlins with ADI, altered cooling, the revised supercharger and injection pumps would of been an excellent start, at least for a fill-in. Similarly, the V-1650-9/11/17 family could of been similarly altered with a further blower stage to produce more power up high. Spitfire VIIs with pressurised cockpits and Merlin 71s were doing ~410mph at 40,000 feet by 1943.

Turbosupercharged P&W R-2800s could have been further boosted on 150 octane. The P-47M and N wee absolute monsters at high altitude combat. Also, the Griffon 100 serise with ADI and the 3 stage supercharger could of made an excellent high altitude powerplant. A Griffon engine Mustang would of been a fearsome beast, even if armament and range had to be reduced for high alt flights. Cut the internal tankage down and fit some turboocharging into the rear.

Me 155B Me P1091 Bv 155A Bv155B Bv P205 Bv 155C
Stage Design Design Design Flight test Design Prototype
Engine DB 603U DB 628 DB 603U DB 603U DB 603U DB 603U
Wingspan 21 m 20 m 20.8 m 20.33 m 18.72 m 19.05 m
Length 11.65 m 11.95 m 12 m 12.1 m 12.276 m 12.10 m
Weight full 5,530 kg 6,037 kg 6,200 kg 6,384 kg
Weight Empty 4,870 kg 5,199 Kg 5,682 kg
Max speed 690 km/h 690 km/h 700 km/h 690 km/h
Ceiling 16,590 m 16,950 m 16,830 m
Armament 3 x MK 108 3 MK 108 1x MK108 2 other MG 1x MK108 2 x MG 151/20 1x MK108 2 x MG 151/20 1x MK108 2 x MG 151/20


thats a chart that i found on this site
http://www.geocities.com/Heartland/Village/4082/int_air/bv155-1.htm

it also talks about the landing gear doors i was discussing above the chart.

The only reason i can see the germans going for such an absolute cieling of over 50,000ft would have been to climb from the superior numbers of allied fighters and bombers as a safety measure, even though that has its flaws due to the fact that american aircraft have superior range, they could just catch the damn thing whenever it ran out of fuel and had to decend to land. I could think of only one more advantage to being so high and fast, and that would be to have a secondary recon mission as something of a back up in case it didnt pan out as a fighter, though i never head anything about this at all anywhere. But it would make sense to have your recon planes that high, and your fighters down below where there speed and manouverability would be more useful at stopping bombers.

The Bv-155 was actually Stage III of the Messerschmit Me-155 program that was handed over to Blohm and Voss in August of 1943. Blohm and Voss naturally changed the design as they saw fit so it no longer looked like the Messerschmitt Me-155B which looked very similar to the Bf-109. The RLM gave Stage III the number 8-155. The first test flight was flown on Feb. 8, 1945 and it quickly showed the problems with extensive cooling and radiator layout and the program was soon canceled. The Ta-152 was a much better high alltitude fighter than the Bv-155B could have been.

Agreed, i like the Ta-152. Manouverable, not with an overkill of a cieling, good speed and amrament, great climb, good enough range. Everything was there that was needed for a good interceptor. Like i mentioned before, id use the BV-155 as a recon platform, using the unattainable altitude advantage and good speed to avoid enemy aircraft, thereby freeing up the Ar-234 from the role, and allowing the small numbers of the jet bombers to be used as just that, bombers.

That I believe. If you could fix the cooling problems then the Bv-155 coudl have made an excellent photo recon aircraft.

DerAdlerIstGelandet said:

That I believe. If you could fix the cooling problems then the Bv-155 coudl have made an excellent photo recon aircraft.

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Yes it would of.

There was nothing wrong with the cooling. On the first test flight coolant loss was because a sleeve and 2 brackets slipped off a pipe. There was some chaffing of other pipes. Rodig noticed the coolant temperature was over 100C which is not high for the Spit limit was 135C. On further test flights the coolant temperature stayed between 107-110C, which was well within limits.

There was numerous other little glitches, which all prototypes, had.

In Nov 1943, the RLM advised B&V to modify the a/c to substitute the MK108 with the MK103. The 3 wing mounted MG151/20 was reduced to 2.

The BV155 is a bit inferior to the Ta-152 (which still had potential for more development).
Both planes operating at 45.000 ft + could make up for a good escort for the Ju-488 high altitude bombers (from which none took off). But this undoubtly wasn´t a conceptual strategy for the Luftwaffe in late 44. It could be that these designs originated in high altitude (stratosspärenflug) ideas developed in 41-43. Scary?

KraziKanuK said:

There was nothing wrong with the cooling.

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If you read my initial post you will see what I was talking about, not that there was a real problem with the cooling system.

DerAdlerIstGelandet said:

If you read my initial post you will see what I was talking about, not that there was a real problem with the cooling system.

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You mean this? "The first test flight was flown on Feb. 8, 1945 and it quickly showed the problems with extensive cooling and radiator layout and the program was soon canceled."

'problems with extensive cooling and radiator layout' Whatever that means?

The program was never cancelled as right up to the last days of Germany in WW2 B&V personel were working trying to finish the V2, WNr 360052.

Read it agian. Problems with extensive colling and radiator LAYOUT.

Oh well I am not going to argue about this.

With the wing span that plane had it couldn't of had a fast roll rate. Just because it could fly high doesn't mean that it would have been a good fighter.

It was meant to be a high altitude interceptor fighter, mainly used against bombers, but could be used against fighters. Its high speed and armaments, as well as good cieling made it reasonable at both

As I said above I dont think that it would have been a good fighter or interceptor especially not with compared to the Ta-152. I think that the Bv-155 would have been a good high altitude recon aircraft though.

Just like i said, for high altitude recon work, it would have been a godsend to the luftwaffe. Large numbers nor hugh production wouldnt be needed, since attrition would be light, from the un-touchable altitude. Bet the germans would have been greatful if they had them around D-day, using those instead of Ar-234's for high speed, high altitude recon work, and saving the jets for nuiscance and harassment missions from altitude against the beach heads, or maybe even against london, knowing how vengeful and insane hitler was.

In a pinch though, the germans would have pushed it into the fighter/interceptor role, they never seemed to really see the use for something until it was too later, and if they did, they changed it so only half, or something would be for the intended role. Like the Me-262 used as a bomber, would be a good example.

carpenoctem1689 said:

In a pinch though, the germans would have pushed it into the fighter/interceptor role, they never seemed to really see the use for something until it was too later, and if they did, they changed it so only half, or something would be for the intended role. Like the Me-262 used as a bomber, would be a good example.

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They would have pushed it into that role because they had to. Most of the aircraft that were used in that role that were not intended for that role, had to be used into that role. It is trying to survive against 1000 bomber raids against your country.

True, anything even marginally suitable would have been pushed into the role. The german people are mercilessly being bombed by a thousand or more bombers, and the fighter pilots have the duty to defend there people. Everyone had some duty to do to stop or help out. Women manned anti-aircraft guns and worked in the radar stations, wireless operators and etc. Firefighters were formed in towns, and the pilots had to go up there and shoot them down. Fw-190s, Bf-109s, Me-110, Me-410, Me-262, and earlier in the war as night fighters bombers were used, Do-17, Ju-88. Everything that could pose a threat to bombers was utilized. Good thing the German SAMs werent done in time..Though if they had the push from the beginning, alot more bombers could have been brought down.