Re: WWII 4 Engine Bombers

On Nov 24, 7:33 am, "Keith Willshaw"
<nospamforke...@xxxxxxxxxxxxxxxxxxxxxxxxxxx> wrote:
"Eunometic" <eunome...@xxxxxxxxxxxx> wrote in message

news:ba518be4-8140-4ec1-8f3f-52d8d54cc891@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx



On Nov 21, 4:14 pm, Albert <albertche...@xxxxxxxxxxx> wrote:
On Nov 20, 11:37 pm, "deemsb...@xxxxxxx" <deemsb...@xxxxxxx> wrote:

Ernst Udet, in charge of such matters as procurment, wouldn't sign off
on the project unless the aircraft could 'dive bomb'. In a 4 engined
bomber with 4 equally distributed engines acrross the wings the
torsional loads generated by the outer pair of engines during a dive
and pullup are such that the arrangement is for all practicable due to
the extra stiffening that would be required and for all considerations
impossible especially as the He 177 had very demanding speed and range
requirements. There were apparently some aerodynamic advantages but
the structural advantages driven more by the need for stressing for
dive bombing was the prime driver.

Ernst Udet was apparently a likeable and affable man with tremenous
piloting skills but he was not qualified for such decisions.
If you ever get to see a video of the flying displays he did in the
USA in the 1920s you'll be left amazed at his airmanship.

Uded commited suicide probably in part due to the He 177 and Me
210/410 fiascos which were managerial rather than technical failures.

Udet died before the He-177 entered service and the policy of requiring
2 nacelles persisted long after his death so its not really correct to blame
him.

Ok I agree, but he had his part to play in setting the stage. He
can't be blamed for unrealistic production plans; there wasn't enough
aluminum for instance.


As for the 210/410 they were rather definitely technical disasters. The
chief test on the Me 210 is on record as saying it had "all the least desirable
attributesan aeroplane could possess." It was prone to nasty stalls and had a
terrible reputation for lethal spins. The Hungarians on the other hand produced a
versionwith most of these vices reduced to manageable levels.

The Me 410 never had any handling problems in fact it handled and
performed rather well, only the Me 210.
In fact it performed rather well when it entered service though by
that time it was 2 years late and far to late to make a difference.
Some Me 210 were produced with the handling problems resolved.

According to Rudiger Kosin, Author of the book "The German fighter
1914-1980" and designer of the Me 210/410 rival the Ar 240/440 and
designer of the Ar 234 the story goes like this.

1 Project is fast tracked and 5 million RM in jigs produced before the
aircraft Me 210 is test flown.
2 Test pilot after first flight says the aircraft steps from the
aircraft somewhat pale and states that the aircraft needs an
lengthened tail and slats. Messerschmitt resists since the scarpping
of the jigs is so expensive and alternative fixes are sought.
3 Kosin states that "it is said that Willy Messerschmitt personally
intervened in the design process to remove the slats and shorten the
tail"
4 Slats, being easily added without scrapping the jigs, are tried but
actually make the problems worse as they snatched, the twin tails are
converted to a single fin with an insignificant improvement in
handling.
5 Contra-rotation of the engines helps but the complications of left
and right turning types had been resisted.
6 The solution turned out to be childishly simple and known from day
1, a lengthened tail improved stabillity and when slats were added
they fixed the problems entirely as the snatching problem came from
the instability of the aircraft.

Somehow it was the Hungarians managed to bypass the bureaucratic
problems and got their Me 210C built with the lengthened tail.
How this happened I don't exactly understand. One gets the impression
that as the Hungarians were planning to build their own under liscence
they were liberated from the managerial politics and were able to act
on what they had been discreetly told.

The Me 210C worked fine. When the DB605 engines were replaced by the
Much larger DB603 engines and in order to escape the Me 210's bad
reputation the name was changed to Me 410. A few Me 210 with
lenghtened tails did Luftwaffe service.

The fact that the Me 410 was over 2 years late cost the Luftwaffe and
fast light bomber (it had an modular internal bomb bay pack in the
nose that could also carry radar and guns), it cost them a relaively
fast night fighter and it cost them a long range interceptor that
might have kept coastal command beufighters, wellingtons and even
mosquitos off the backs of the u-boats and it cost them an aircraft
that could have inflicted heavy damage to US day bombers, at least
untill escorts came in use in numbers. The Me 210/41 not only was to
replace the Me 110 but also some of the Ju 88's functions.

Willy Messerschmitt was dispossesed of his ownership of his own
company and proably barely avoided jail over the affair. Having said
that the buerocrats in the RLM and Luftwaffe were probably just as if
not more responsible. They both made mistakes and to hide their own
sense of guilt lacked were too ashamed to do their job and and point
out the deficiencies of each other. In the end both sides bungled on.

The most serious cost was in the damage it caused to manufacturing
industry.

For instance Heinkel Nord in Rostok was ordered to gear up and tool up
to produce Me 210/410, when the program became delayed they had to
switch to Ju 88 production which it could only do inefficiently. The
disruption was immense and it prevented the efficient implementation
of low labour manufacturing throughout German industry and several
airframe companies as well as sucking up scarce resources.

The Me 210/410 could have been ready slightly delayed, perhaps delayed
by the need to make new jigs and tools.

Having said that, the whole managerial mess might have been better
dealt with by *** caning the whole project to dispose of the
managerial difficulties and relying on that private venture' the He
219 which could have fulfill many of the Me 410s intended roles. It
had good handling and very good speed but was only developed as a
night fighter. If chosen for mass production the He 219 had been
configured to be very efficient to mass produce though it was only
ever produced in small runs so could not exploit this.

The Me 210/410 program failure was rather one of organizational and
cultural failure since it was for this reason that they could not
'bite the bullet' to implement minor design changes because they were
embarrassing to to many people.. The He 177 seems to have suffered
from the same kind of political problems.

In fact the political and managerial problems seem to have been
overcome after the Me 410 program was finished. These problems which
in any case emanated from using what would today be called "fast track
project management" witch has a big payoff but needs enormous skill to
pull of. With appropriate cultural and risk management processes
fast tracking can work.

You can see after the Me 210/410 project that Messerschmitt advanced
projects such as the p.1112 v2 http://www.luft46.com/mess/mep1112.html
and p.1011 http://www.luft46.com/mess/mep1101.html (really a test bed
for the former)
that the development programs were being phased with good feedback and
feed forward between programs and identification of high risk areas
with remediation through a secondary plan or flexibility in the risky
area eg the abillity to vary wing sweep within the design.

For instance to overcome the handling problems of span wise flow on
swept wings provision was made in designs to adapt wing changes and to
increase slat area from 13% to 20% if required. Provision was made
for power controls and hydraulic flutter dampers should they be
required etc.

.