soc.history.war.world-war-ii

On Mar 1, 3:56 am, "Tero P. Mustalahti" wrote:
> YMC wrote:
> > Apparently the Luftwaffe were interested in Japan's Mitsubishi Ki-46-II Type
> > 100 "Dinah" recce plane. Did they express serious interest in other
> > aircraft? Especially, in light of the successes at Pearl Harbor and Kuantan
> > (sinking of Prince of Wales and Repluse).
>
> The Ki-46 was an exceptional recce plane, but I can not think of any
> other Japanese aircraft, which would have been similarly superior to
> German developed ones. Th A6M did have an impressive range, but it was
> not at all suited to German fighter tactics.

SNIP stuff about soviet fighters

>
> As for bombers, the Japanese medium bombers were even more vulnerable to
> interception than the standard German medium bombers. Their additional
> range might have been handy in the Eastern Front and perhaps in the Med,
> but without long range escorts their usefulness would have been rather
> limited. SNIP stuff about manufacturing long range japanese fighters and bombers.

> Tero P. Mustalahti

The Germans would have benefited from Japanese technology,
unfortunately their geographic separation made exchanges difficult.

The Japanese had developed laminar flow wing profiles, this was (I
believe) all their own work and owed nothing to Eastman Jacobs at the
USA's NACA that lead to the P-51 and I believe was complete by 1940.
>From about 1942 onwards the technology is incorporated into several
Japanese aircraft. Many of these aircraft still had the exceptional
range of Japanese aircraft (about twice that of US medium bombers and
1.5 times that of the Germans) but now combined with armoring and
self sealing fuel tanks.

The Germans had built laminar flow profiles but didn't like their
stability characteristics and nothing seems to have come of it; don't
know what came of the research (probably the talent was focused on the
supersonic stuffm and it is known that Prandl's report on the P-51
correctly indicated that the wing wasn't laminar in service due to
dirt etc) but it is documented in "a history of aeronautical research
in Germany" which is even on Google books. (German ww2 work was
apparently focused on active boundary layer suction and they were
trying to develop porous membranes)

The Japaneses passive laminar wings however seemed to have been very
successful:

G4M2 Betty from 1942 onwards had laminar flow wings and later models
incorporated Armour.

C6N Saiun, Nakajima 'Myrt'
The need for a high-speed carrier based reconnaissance aircraft
was
unique and reflected the increasing Allied air superiority.
The C6N
was an advanced design, with a small laminar flow-wing with
extensive
flaps and slats. The operational need disappeared when the
carriers
were sunk, and some C6N's were converted to night fighters.
463 built.
Type: C6N1
Function: reconnaissance
Year: 1944 Crew: 3 Engines: 1 * 1460kW Nakajima Homare 21
Speed: 610km/h Ceiling: 10500m Range: 5310km
Armament: 1*mg7.92mm

N1K2-J Shiden Kai (Violet Lightning Modified) and its laminar flow
wings. Considered among the finest fighters of the war.

Ki.93, Rikugun
The Ki.93 was first designed as a twin-engined long-range
fighter, but
emphasis later shifted to a multi-role fighter-bomber. The Ki.
93 looked
very promising, with its laminar-flow wing, powerful engines,
sleek
fuselage, extensive armour and 57mm gun. But it was flown only
once
before an accident and bombing halted testing.
Type: Ki.93
Function: fighter-bomber
Year: 1945 Crew: 2 Engines: 2 * 1970hp Mitsubishi Ha-214
Speed: 624km/h Ceiling: 12050m Range: 2000km
Armament: 1*g57mm 2*g20mm 1*mg12.7mm

J2M Raiden - Imperial Japanese Navy fighter that was intended to
replace the A6M Zero but was constantly delayed for technical
problems. Emphasis was on speed and protection over manuverability,
had armor, self sealing tanks, laminar flow wings, and carried 4 x
20mm cannons.

************************

"The Tripartite Pact of 27 September 1940 for military and technical
cooperation between Germany, Italy, and Japan required reciprocal
exchanges of raw materials, equipment, and personnel. Germany and
Japan encountered difficulties in their attempts to carry out this
exchange, though. Axis blockade running vessels were being sunk
with increasing frequency thanks to MAGIC intercepts and decrypts.
When Germany invaded Russia in June 1941, shipping war material and
personnel via the Trans-Siberian Railway ceased abruptly as Russia
became an Anglo-American ally.[2] The fragile Japanese-Russian
non-aggression pact forced a maritime exchange, although there was
an alternative plan to fly the precious cargo and personnel across
Russia to Japan in three Junkers aircraft.

Between December 1940 and June 1941, five German merchant vessels
departed Japan, with three arriving in Bordeaux. By February 1942,
nine German and three Italian vessels had made the voyage, but three
were sunk en route. Fifteen Axis blockade runners departed the Far
East in the winter of 1942-1943, but only seven reached Europe,
while in 1944 only one of five ships departing Japan reached
Nazi-occupied Europe. In 1942, a Japanese submarine cruiser
completed a mission from Japan to France and back but fell victim to
a mine in Singapore harbor."

************************

The biggest area the Germans lost out on was the Japanese multi cavity
magnetron which was independently developed and built by Dr Shigeru
Nakajima in Japan and actually about 1 year ahead of Randall and Boots
work in the UK. They had the type 22 10cm surface search radars in
service on by 1942 initially about 100 were produced but the super-
regenerative receivers required skilled personnel so they were only
deployed in larger ships. Ironically it wasn't until 1944 that
incorporation of the German Rehbok auto calibration and a super
heterodyne circuit that they set could be widely deployed on subs and
destroyers, some 300 of the upgraded type 22 were produced.

The Japanese never deployed PPI sets but note that the Royal Navy only
had PPI centimetric radar from mid 1943 onwards. The Germans had PPI
by 1940 on a single GEMA 'panorama' but it wasn't deployed till late
1943 with the sets only becoming common by mid 1944 since the antenna
needed to be so large with the large wavelengths in use. Another
irony is the Japanese struggling to build Wurzburg copies in 1945 even
as the Germans were just getting their own microwave sets in service.