Re: He274/He277
- From: "Geoffrey Sinclair" <gsinclairnb@xxxxxxxxxxxxx>
- Date: Fri, 15 Sep 2006 18:10:46 +1000
"Eunometic" <eunometic@xxxxxxxxxxxx> wrote in message
news:1158158253.562872.319130@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Keith Willshaw wrote:
"Eunometic" <eunometic@xxxxxxxxxxxx> wrote in message
news:1158063140.094444.8050@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
guy wrote:
I know the history of the two types, but how much commonality was
there
between them?
The He 277 was an He177 modded to carry four engines, The He274 was
designed from the start for 4 engines, based around the He177
was much interchangeable?
They seem to have derived from the same He 177,
The He 277 (also known as the He 177B) was a 4 engined He 177; it was
'engineered' in Heinkels Vienna works. It used conventionaly
supercharged engines and was pressurised. It was not supported by the
RLM and was somewhat of a hidden private project but when it was
finally supported was they demanded immediate production. Production
was cancelled on Jult 4th; along with a lot of other projects
presumably due to the allied landings. The aircraft was flown and have
very positive evaluations and very good performance: speed
It was impressive aircraft with a speed of 354mph and range of between
3700 and 4300 miles, it was pressurised and heavily armed with remote
controled turrets; in every way comparable to the B-29.
Hardly
The B-29 could carry a 20,000 lb bomb load and had a combat radius
of over 3000 miles
No.
The B-29 had a ferry range of 5600m which is rounded up to 6000 miles.
The practical opperational radious with 5000lbs of bombs was around
1800 miles.
http://www.csd.uwo.ca/~pettypi/elevon/baugher_us/b029-03.html
Note what the web site actually says,
"Maximum range was 3250 miles at 25,000 feet with 5000 pound bomb
load. Practical operational radius was 1600-1800 miles. Maximum ferry
range was 5600 miles, rising to 6000 miles with the extra fuel.
A load of 5000 pounds of bombs could be carried over a 1600-mile
radius at high altitude. A load of 12,000 pounds of bombs could be
carried over a 1600-mile radius at medium altitude."
The practical operational radius is before or after the weight stripping
program initiated in 1945? Some 1,900 pounds of weight removed.
Plus the reduction in fuel loads when the bombers no longer had to
avoid Iwo Jima.
Now note the bomb load/range performance of the B-29B.
The He-177/277 could carry up to 12,000 lb and had a combat radius
of 1000 miles
The He 277 was a vastly modified from the He 177:heavier, faster, more
armament, bigger bomb bay.
The He 277B-5 had a speed of 358mph and a range of just over 6000km
3750miles.
This is the maximum range.
In case people were wondering the He177 could carry around 14 metric
tons of load, the He277 around 22.5 metric tons of load.
The He 277B-6 had a slightly higher speed and a range of about
4500miles. It was the maritime reconiseance version and used Jumo 213F
engines.
This is a version that was never built. And it was the B-7 version
that was the maritime reconnaissance version.
Even the shorter ranged He 177A-5 had a range of 3105 miles WITH and
external Hs 293 missile. The He 277B-5 had greater range again.
The He277B-5 maximum range was around 3,700 miles.
Smith and Kay note the range of the He177 with 2 Hs293 was
around 3,400 miles, and with two FX 1500 some 3,100 miles.
Of course the bomb bays had been turned into fuel tanks for
the purpose.
To compare the two types you need to give the allied aircraft
bomb bay tanks and carriers for the HS293, which weighed in at
about 1 metric ton, or the FX 1500, which came in at 1.5 metric tons.
The average bomb load of the Lancaster over all bombing sorties
for the war was just over 10,000 pounds. So add between around
2 and 3 tons of fuel in the bomb bay, or around 630 to 945 British
gallons to the maximum fuel load of 2,154 gallons.
Note the Lancaster range is quoted as 2,530 miles with 7,000 pounds
or around 3 metric tons of bombs, and 1,730 miles with 12,000 pounds
or around 5.5 metric tons of bombs.
Meantime the B-17F Ferry range was 3,680 miles and the range with
6,00 pounds of bombs at 10,000 feet and 200 mph was 2,200 miles.
In reality the radious of the He 277B-5 bomber would be somewhat more
than 1500miles with about 2000kg of internal bombs.
Ah one of those guesses again, with 4,400 pounds of bombs.
The usual Lancaster bomb/load range charts do not go to that low
a bomb load.
It was comparable with the Lancaster/Halifax/B-17 generation
The He 177 was superior to not only the Lancaster/B-17 but the Avro
shakelton as well. Its had a range of 3105 miles WITH an external Hs
293 anti shipping missile. Much more than the Lancaster or B-17. It
was also much faster at 358mph as opposed to around 285 for the B-17and
Lanc.
The He177 had a top speed of around the same as the Lancaster and
B-17, and all you need to do is find the He177 using conventional
bombs to compare the figures with allied types and see the problems
with the claims.
As for the Shackelton this has the problem of the fact the type first flew
in 1949 and was still around in 1970, with considerable modifications.
Assuming we are talking about the mark 1 and 2, then the range was
3,800 miles at 200 mph, maximum internal bomb load was 20,000 pounds.
The type had around 20% more wingspan, 20% more length and 10%
more wing area than the Lancaster.
The He 277 was another class above the He 177 and unlike the Lincoln
was actually pressurised.
The He177 "another class" appears to be the usual generous
praise for a German design. The pressurised claims seem to be
unsupported.
of western bombers in terms of performance but rather less reliable.
The B-29 was extremly unreliable and vast numbers burned out and
crashed due to the propensity of its engines to catch fire and destroy
the main wing spar. Uhdersized crowded cowlings were part of the
problem (just like on the He 177)
This is really quite funny.
Extremely unreliable?
Vast numbers burned out?
Try this for size.
Total B-29s built by the end of August 1945 was 3,763. Some
772 lost by the end of August 1945. The 20th Air force lost
some 502 B-29s in combat and accident.
The 20th Air Force noted B-29 losses on combat operations as
74 to enemy aircraft, 54 to flak, 19 to a combination of flak and
fighters and another 267 to other causes, total 414. Engine fires
would be a major component of the other cause losses but they
also include where the USAAF did not know the cause of loss.
The B-29 flew some 31,387 combat sorties of which 29,153 were
classified as effective. Weather was blamed for 19 of the aborted
sorties, mechanical difficulties for 1,634 sorties and the rest to
other reasons.
Those 29,153 effective sorties dropped some 169,676 short tons
of bombs, or 5.8 short tons, or 11,640 pounds of bombs on average
per sortie.
Tokyo was around 1,500 miles from the B-29 bases.
Some 10 B-29s were lost being ferried to the front line. Which
would mean some 260 were lost in the US.
For the 8th Air Force it had 334,904 heavy bomber sorties of
which 274,921 were classified as effective. Weather was blamed
for 26,930 of the aborts, mechanical failures for 11,839 with other
causes making up the rest.
Some 12,291 heavy bombers, B-17, B-24 and B-32, were lost by
the USAAF overseas plus 1,989 in the US.
The He 177 never had the time to prove itself. The problem does not
seem to have been the aircraft itself though by the A5 vaiant most of
the problems had been solved.
First flight in 1939, production acceptances began January 1942, so
2 years prototype development and it was still considered unreliable
in 1944. The first major use of the A-5 version was in November 1943.
In 12 operations starting in January 1943 flying transport sorties to
Stalingrad some 7 He177A-3 were lost to engine fires. So how much
time is needed for the He177 to prove itself?
Meantime the B-29, first flight September 1942, first production July 1943.
Needless to say with this production schedule there were bugs to work
out, including the engine fires.
By the way the He177A-5 version had so much of the bomb bay blanked
off for fuel tanks the internal bomb load was down to around 1,000 kg.
By the way the remainder of the Eunometic post is from someone
called Huck, see
http://forum.axishistory.com/viewtopic.php?p=532279
Now, I don't want somebody to believe that He-177 service was trouble
free. The problems that He-177 had in service were many and severe,
however they were not caused by mechanical failures. Instead LW own
inability to service and use in effective manner this complex aircraft
caused most of the difficulties.
Actually the engine fires were an intrinsic hazard of the design,
Rechlin did the modifications which eliminated most of the problems,
but these changes were not taken up for quite a while.
Anyway I gather the idea is to shift the blame from the engineers
to the users.
Here's a quote from 'Heinkel 177, 277
274' by Manfred Griehel and Joachim Dressel, ISBN 1 85310 364 0,
containing a German wartime report on He-177 which perfectly summarizes
how the LW failed to exploit the qualities of this advanced aircraft.
Note the quote is from May 1944, when the Luftwaffe was in real
trouble, not say 1941 or 1942. Or is the idea to claim the Luftwaffe
was in crisis from 1942 onwards? So they botched the He177
introduction?
What I like is the way maintenance was expensive thanks to parts
of the design.
Quote:
In May 1944 Major Schubert of the Luftwaffengeneralstab and
Reichsmarschall Goring's Adjutancy was finally appointed to establish
the principal reasons for the delays experienced in re- equipping
Luftwaffe bomber units with the He 177. Nothing needs to be added to
his report:
Most of the aircrew of units selected for re- equipment with the He 177
were operationally 'tired-out' and relatively few were from front-line
units. The necessary personnel consisted primarily of Young, often
inexperienced aircrews, and for reasons of capacity their conversion
training at operational training and replacement Gruppen could only be
completed in relatively few cases. Most of the young pilots had only
nine to 12 months of practical flying experience prior to being
transferred to such a complicated aircraft as the He 177.
Apart from that, the new operational crews had been trained on the Ju
88, and most had hardly any training in the art of night-flying. The
necessary conversion training meant the compulsory withdrawal of
operational He 177s for use as trainers, which in turn led to an
overload of work for the technical personnel due to the numerous
instances of damage suffered by these aircraft as a result of the
training activities.
Matters were made all the more difficult by the fact that some of the
ground personnel had not been pre-instructed on the He 177. In
addition, the vast majority of the technical personnel arrived at their
He 177-equipped bomber Gruppen several months after the units had first
received their re- equipment orders. By spring 1944, some units were
still short of about 50 per cent of engine fitters. Some of the other
personnel first set eyes on the He 177 upon arrival at their assigned
unit's airfield, their instruction and training on the Heinkel bomber
having to start there and then.
The supply of aircraft servicing tools and appliances also did not keep
up with deliveries of He 177s. Thus, for instance, the wing attachment
cranes needed to facilitate powerplant changes arrived several months
after the delivery of the aircraft themselves, and even then they were
too few in number. For IV/KG 1 there was no specialised engine-changing
equipment at all, and for this reason the unit had to suspend all
training activities in mid-April 1944.
The 'engine circulation' (service units - repair depots - service
units) also did not flow as it should have done at first, because of a
lack of transportation. Neither the supply of new engines nor the
return of DB 606/610s in need of repair functioned properly, least of
all the supply of exchange powerplants to individual airfields. It
wasn't until April 1944 that these shortcomings were effectively
overcome, but they were never fully eradicated.
According to Major Schubert, the time expenditure required for the
maintenance and servicing of the He 177 was incomparable with that of
any other operational aircraft in service with the Luftwaffe. The
jacking-up operation to change the main undercarriage tyres alone
(which had to done at least twice as frequently as on other aircraft
types) lasted some 2fi hours using the prescribed mechanical spindle
blocks. Yet by early summer 1944 far too few of these 12-ton spindle
blocks recommended by the manufacturer were available to He
177-equipped units.
The layout of the powerplants too did not exactly help attempts to
carry out the necessary servicing work. Because of the inaccessibility
of the coupled engines their dismounting took considerably longer than
similar work on, for example, the Ju 88 or He 111. Due to the low
training level of the technicians, a 25-hour control check on the He
177 usually took two, sometimes even three days.
Criticism was also made of the airfields selected to receive the He
177. Apart from Aalborg in Denmark, all of the others were already
completely overcrowded, and lacked the potential for dispersal,
camouflage and suitable protection of their aircraft against bomb
splinters and shrapnel. For this reason low-level attacks by Allied
aircraft caused great losses amongst the He 177s parked out in the open
from 1944 onwards, especially as the airfields were now constantly
within the range of both fighters and bombers. To make matters worse,
this vulnerability to attack had a knock-on effect on He 177 training
activities, which sometimes had to be reduced by up to per cent because
enemy aircraft were on their way and air raid warnings came into force.
No consideration had been given to the fact that the technically
complex He 177 required sufficient hangar space for maintenance and
repair purposes, especially during the winter months. The delays caused
by this shortcoming alone may well have been responsible for the
postponement of He 177 operations by some six months to a year.
Alternatively no consideration was given in the design to the fact
wartime airfields would be short of hangars and maintenance facilities.
Geoffrey Sinclair
Remove the nb for email.
.
- References:
- He274/He277
- From: guy
- Re: He274/He277
- From: Eunometic
- Re: He274/He277
- From: Keith Willshaw
- Re: He274/He277
- From: Eunometic
- He274/He277
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