More advanced aircraft during WW2? Germany or Japan?

[machine shop tom]

DonL

I think you need to consider what time periods you are talking about. For instance there is no doubt that Germany had significant problems with the fuses on her torpedos for at least the first 12 months of the war. They were fixed that is true but the million dollar question is when.

Doenitz initiated a temporary fix for the torpedo pistol (detonator) problem by copying the British 21" torpedo contact pistol. This was found on the captured HMS Seal, and the design was copied and used until, 2 years later, a fully reliable German torpedo was perfected.

Japan had no such problems. And nothing by any Navy could compare with the Type 93 torpedo.

But then again, that wasn't an airplane.

tom

 

[Budman]

My 2 Cents, During WWII my Dad who was working at Chandler Evans as a Experamental Carburetor Specialist got to examine a captured Zero carburetor. He always said it was a machinists version of a work of art. He noted that very close tolerances were followed in its construction and additional un-needed work that was applied to its exterior, such as polishing, and deburring.

 

[Glider]

=DonL;627702@ Glider

Sorry Glider then we have different sources about the LT F 5b / LT I.
From my german sources it was in service late 1939 and solved the heavy problems of the LT F 5a.
Then the complete production was canceld in 1940. So the german navy imports the italien arial Torpedos to have a stock of pieces. The new production of the LT F 5b / LT I from 1941 till end was very small because for most people it was not important enough.
Also I'm a big fan of the navyweaps board but my german sources tells an other story of timeline.

Here are some data for the FW 187 night fighter projekt

Fw 187 - Kampfzerstörer 1942

Wing span: 15,3
Wing Surface Area: 30 qm
Length: 12,45

Crew: 2 (200 kg)
Empty weightt: 5600kg
Maximum weight: 8200 (with 1 x 1000 kg Bombe)

Engine: DB 605

range: 1200 km without
----------------------2100km with Droptanks

Guns:
4 x 151 / 20 with 250 bullets
2 x 131 mit je 450 bullets -
1 x MG 81 mit 750 bullets
(gesamt: Waffen 392 kg; Mun 306 kg)

Bombs:
maximal 2.000 kg
1 x 1000 kg + 2 x 500 kg or
1 x 1000 kg + 4 x 250 kg or
10 x 50 kg bzw. 10 x AB 23 / 24

Thanks for the information, at least you could see where I was coming from. Re the FW187 again it seeems to depend on the timescales, clearly this NF version differed considerably from the early war versions. For whatever reason the Luftwaffe had a hole in their capability for approx the first 18-24 months of the war.

 

[Glider]

Kurfurst
Your figures are interesting but all hey prove is that Germany had the F5B and the F5W over this period. The F5W is the german designation for the Italian Torpedo and as we agree the F5B was the German torpedo which according to the NAV site entered service in 1941.
You have to ask the questions
a) If the German Torpedo was effective pre war then why take it out of production?
b) If the German Torpedo was effective why buy the Italian Torpedo in the first place?

 

[Kurfürst]

Well both of your questions were already answered by DonL and partially my post, so I wonder what point is asking them again?

We have already established that the Germans had their own torpedoes and torpedo bombers at the start of the war; the site is simply wrong in claiming that their own torp did not arrive until late 1941.

 

[cherry blossom]

Well both of your questions were already answered by DonL and partially my post, so I wonder what point is asking them again?

We have already established that the Germans had their own torpedoes and torpedo bombers at the start of the war; the site is simply wrong in claiming that their own torp did not arrive until late 1941.

The issue of whether the Germans had air dropped torpedoes in 1939 depends on whether you count useless torpedoes. There are torpedoes that can be used successfully and others that give little chance of success or survival of the aircraft against a target with anti-aircraft guns. The data at NavWeaps - Naval Weapons of the World - 1880 to Present explains the difference by giving for several torpedoes the speed and height at which the attacking aircraft must fly in its straight approach before dropping. The Germans did have the F5 air dropped torpedo in 1939. It was possibly the worse air dropped torpedo of WW2 and could be dropped at up to 75 knots from 15 to 25 m. Its speed was 33 knots. Thus an attacking aircraft needed to approach the target flying at 75 knots or less. It probable had the same defective striker as their other torpedoes. For comparison, the F5b of 1941, which was copied from the Italians, could be dropped from 183 knots and 120 m after some development (I could only find data from the L2 version) and ran at 40 knots. I think that the Japanese Type 91 Mod 1 in service in 1939 was already capable of being dropped faster and higher than the F5b L2 but I have not found the data (the attacks on Prince of Wales and Repulse showed the performance). Later Japanese torpedoes could be dropped from 350 knots. Japanese torpedoes ran at 41-43 knots depending on models. Early American torpedoes were poor but slightly stronger than the early German F5s and could be dropped from 15 m at up to 110 knots and ran at 33.5 knots. However, this improved to 730 m and a speed of 410 knots by 1944 and quoting directly "On one occasion in early 1945, six torpedoes were dropped from altitudes between 5,000 and 7,000 feet (1,500 to 2,100 m). Five out of the six were observed to make their runs hot, straight and normal."

 

[Glider]

Well both of your questions were already answered by DonL and partially my post, so I wonder what point is asking them again?

We have already established that the Germans had their own torpedoes and torpedo bombers at the start of the war; the site is simply wrong in claiming that their own torp did not arrive until late 1941.

Kurfurst
Cherry has covered the main points. The site points out that the Germans did have a very poor aerial torpedo pre war, that the Germans own torpedo came into service in 1941 and that the Germans used Italian torpedo's.

If you have support for your statement that Germany had an effective home grown torpedo in service at the start of the war then supply your evidence. Your chart was interesting, but only showed the stocks of the Italian and later German torpedo's.

My questions were for you to think about and they key part of the question was Why.

a) If the German Torpedo was effective pre war then why take it out of production?
b) If the German Torpedo was effective why buy the Italian Torpedo in the first place?

Do you really think that you are going to war against one of the largest Navies in the world and take your only effective torpedo out of production. I don't think so.

 

[parsifal]

I am relying on three principal sources

1) , Naval Weapons Of WWII, John Campbell Conways Maritime Maritime Press, 1985
2) NavWeaps - Naval Weapons, Naval Technology and Naval Reunions - Navy Weapons
3) The Luftwaffe and the War at Sea 1939–1945: As Seen by Officers of the Kriegsmarine and Luftwaffe, D.C. Isby (ed.), Journal For Maritime research

Campbell states at Page 262…." Airborne 45 cm torpedoes had been used by the German Navy to a limited extent in the First World War, and had sunk three merchant ships….it was manifestly impossible to develop them in secret (in the interwar years). (The Germans) decided that the Noregians at Horten were ahead of other countries in the area of Torpedo attitude and roll during the drop and a contract was placed in March 1934. The target was 600 by 1939, but this figure was never reached in delivery. Production at the outbreak of the war was only 5 per month (Campbell states elsewhere the German stockpile of air torpedoes was less than 100, which accords to the list provided by Kurfurst, except that they are F5as and not F5bs).

In October the torpedo stocks underwent a series of trials. In a practice exercise, of 52 drops there were 26 failures. Attempts were made to purchase Italian Fiume torpedoes, but there were difficulties over the supply of scarce materials, and the contract was not signed until March 1939 Eventually (source three says 1941) about 1000 of these torpedoes were delivered. At the beginning of the war there thus only the modified Horten torpedo F5 carried by the slow He 115 seaplane, and neither inspired much confidence.

From March 1940, all further development (of aerial torpedoes) was stopped altogether by the Navy… (Some time after this) the Luftwaffe took air launched torpedo development over from the Navy. Development continued at a slow pace, resulting in late 1941 in the development of the F5b, which with some modifications remained in service until the end of the war. . The F5B was a compromise solution"…..

Campbells technical data reveal in glaring terms why the F5a was a failure. This torpedoe had a effective range of 2000 metres @ 33 knots. Launch speed was 75-80 knots, and drop height could not exceed 25 metres, explosive charge 200 kg

The F5b which was introduced in November 1941, though it took some time to build up stocks. I still think it was inferior to the Italian Fiume Torpedo. The characteristics of the two torpedoes according to Campbell are

F5b: 2000 metres @ 40 knots, 6000 metres @ 24 knots, launch speed 120 knots (later increased to 150 knots in 1942 with the K3 tail). With further modifications (the L2 tail) in 1944, the F5b achieved safe drop speeds of 183 knots. Drop heights also increased. In 1941 it was 30 metres, increasing to 40 metres in 1942, and finally reaching 120 metres in 1944. Explosive charge 200 kg

F5w (Italian type) 3000 metres @ 40 knots, 8000 m @ 30 knots , launch heights and speeds not stated. Explosive Charge 200 kg

None of these sources ever make reference to the g7e torpedoes being used in the aerial role.

The Japanese 18 inch aerial torpedoes had the following characteristics.
Type 91

Model I (introduced 1931)
2000 metres @ 43 knots, launch speeds 260 knots, warhead size 150 kg

Model 2 (introduced April 1941)
Same as above but with 205 kg charge

Model 3 (introduced October 1941)
Same as above, except charge is 240 kg, and launch speed of 350 knots

The Model Type 94 increased the torpedo speed to 48 knots, and the effective range to 3000 metres (at that speed) warhead size was eventually 553 lbs. Drop speed was over 400 knots

Launch heights for all Japanese torpedoes were about the same, at 100 metres altitude, or less

Isbys book, which is really a collection of wartime and postwar accounts by German Naval and air officers, along with some intelligence reports by the US Navy, has been reviewed by the eminent Richard Harding (University Of Westminster ) who makes the following pertinent observation "The review of air operations 1939–40 by the German officers of the US Naval Historical Team and by Gaul is again narrative, but highlights the tactical and operational limitations of the air campaign, from lack of proper co-ordination and the political disputes that led to the Luftwaffe's assumption of complete responsibility for offensive war at sea, to the lack of mines, the slow development of the aerial torpedo and the lack training of airmen for operations over the sea".

 

[parsifal]

Deleted Repeat Post.

 

[DonL]

My questions were for you to think about and they key part of the question was Why.

a) If the German Torpedo was effective pre war then why take it out of production?
b) If the German Torpedo was effective why buy the Italian Torpedo in the first place?

@ Glider

The major problem was with the LT F 5a.
The LT F 5b / LT I solved all the problems and was an major improvement and in service late 1939.
The whole production was cancelled 1940 bei "Führerentscheid" (decision direct from Adolf Hitler) because he and other people (consultants) are thinking that arial torpedos didn't do their job and lack on success and raw materials, manpower and productiontime can get to other weapons.

I realy understand that is very difficult to believe but it's true.
After succesfull missions of the RAF/RN in 1940 with arial torpedos the decision was cancelled and a new production of the LT F 5b / LT I begins. But at that time the germans had only 40 pieces in stock and the production output was so small that they import the italian torpedo to have more pieces. The production output was small the whole war so they import additional italien torpedos to have enough pieces in stock.

And no the LT F 5b / LT I was no cover version of an italien torpedo.
The LT F 5 1934 was a cover version of the norwegian "Horton Torpedo"
The LT F 5a was a german developement and the b too.
The b had no problems and was good and in service end 1939!

Data of the LT F 5b 1939
2.300 Metern @ 40 Knoten, 3.500 m @ 33 kn or 7.500 m @ 24 kn.
launch 50m high; speed 260km/h
200kg explosive

 

[parsifal]

The F5b was not in production, or even under development in 1939, according to three independant sources. Its development was not begun until aerial torpedo development was taken over by the Luftwaffe, in March 1940. It entered service, late in 1941, according to these sources. I have not seen any conclusive evidence from either Kurfurst or yourself to refute these sources

 

[renrich]

In late 1942 the US conducted comparison tests with the latest US fighters and the captured Zero Model 21 from the Aleutian campaign. The US fighters were the P38, P39, P40, P51, F4F4 and F4U1. During the tests, the Allison powered P51 had mechanical problems and failed to complete the tests, the P40 also had major problems so no data was gathered, the P39 ran out of fuel before the tests were completed. The Zero continued to operate flawlessly during all the tests. One could come to several conclusions from this comparison:

The Allison engine was troublesome and perhaps radial engines were more reliable?
The tech people on the Zero were better than those on the US fighters?
The Zero was on the whole a more reliable design than the US fighters?

One conclusion impossible to avoid during the tests was that the Zero was overall a well built and well designed aircraft.

It would be interesting to be able to compare the reliability of the Japanese AC versus those of all the other combatants.

 

[FLYBOYJ]

In late 1942 the US conducted comparison tests with the latest US fighters and the captured Zero Model 21 from the Aleutian campaign. The US fighters were the P38, P39, P40, P51, F4F4 and F4U1. During the tests, the Allison powered P51 had mechanical problems and failed to complete the tests, the P40 also had major problems so no data was gathered, the P39 ran out of fuel before the tests were completed. The Zero continued to operate flawlessly during all the tests. One could come to several conclusions from this comparison:

The Allison engine was troublesome and perhaps radial engines were more reliable?
The tech people on the Zero were better than those on the US fighters?
The Zero was on the whole a more reliable design than the US fighters?

One conclusion impossible to avoid during the tests was that the Zero was overall a well built and well designed aircraft.

It would be interesting to be able to compare the reliability of the Japanese AC versus those of all the other combatants.

I remember reading a post on here a while back that quoted a former Japanese fighter pilot who stated that in the field, many Japanese fighters suffered from unreliability, lack of spares and interchangeability was poor.

 

[timshatz]

In late 1942 the US conducted comparison tests with the latest US fighters and the captured Zero Model 21 from the Aleutian campaign. The US fighters were the P38, P39, P40, P51, F4F4 and F4U1. During the tests, the Allison powered P51 had mechanical problems and failed to complete the tests, the P40 also had major problems so no data was gathered, the P39 ran out of fuel before the tests were completed. The Zero continued to operate flawlessly during all the tests. One could come to several conclusions from this comparison:

The Allison engine was troublesome and perhaps radial engines were more reliable?
The tech people on the Zero were better than those on the US fighters?
The Zero was on the whole a more reliable design than the US fighters?

One conclusion impossible to avoid during the tests was that the Zero was overall a well built and well designed aircraft.

It would be interesting to be able to compare the reliability of the Japanese AC versus those of all the other combatants.

While there may be something to the test data, it would be ill advised to judge too much about the aircraft in question regarding mechanical reliability due to one test only. There seems to have been only one of each type used.

Maybe they got a very well made Zero.

The inverse is true as well. Maybe the Allied birds were all dogs (odd but not impossible to happen, especially with mass production and an expansion in the production capacity) of the production run.

In short, the size of the test sample is on the small side to derive conclusions.

On a different note, it's odd they didn't test the F6F in that sample.

 

[davebender]

The Allison engine was troublesome and perhaps radial engines were more reliable?

Allison engine unreliability is an easy conclusion to reach. However by 1942 the U.S. has plenty of test data for the RR Merlin, DB601 and Jumo211. There was no reason to think that all liquid cooled V12s were as crappy as the Allison. Unless American military leadership were living in a state of denial, refusing to believe that some other nations built superior liquid cooled aircraft engines.

 

[cherry blossom]

Firstly, I must apologise for confusing the F5b and F5w torpedoes in my previous post.
Secondly, may I mention a discussion of shipboard anti-aircraft gunnery in the RN by Philip Pugh, in "The Royal Navy, 1930-2000: innovation and defence" by Richard Harding, p19-41. He notes that the RN's main failure in its pre-war planning was to underestimate the speed of attackers and mentions that ships could generally defend themselves from slow attacks, giving the example of the Channel Dash. This doesn't seem true of Bismarck or of the Italian Fleet but would any reader volunteer to fly a Ju 88 towards a British battleship in a straight line at the speed and height required for a successful launch of an early F5b?

 

[renrich]

I agree that no valid conclusions could be drawn as far as reliability is concerned, which is why I used the question marks, but it is strange that two of the four Allison engined aircraft had engine performance problems and it certainly points out one of the flaws in the P39 design. One wonders why the AAF aircraft were not seemingly well prepped for the tests. I suspect that when the tests were conducted that a production F6F was not available. The Aleutian Zero, according to this book, had an unseemly end. In 1944 a SB2C, Helldiver, inadvertently taxied into the Zero and destroyed it from the tail to the cockpit. "The Beast" strikes again.

 

[FLYBOYJ]

In 1944 a SB2C, Helldiver, inadvertently taxied into the Zero and destroyed it from the tail to the cockpit. "The Beast" strikes again.

It was hungry.

 

[timshatz]

It was hungry.

Or flown by the pilot commonly known around the base as "Herr Jackass"

There's at least one on every base.

 

[timshatz]

I agree that no valid conclusions could be drawn as far as reliability is concerned, which is why I used the question marks, but it is strange that two of the four Allison engined aircraft had engine performance problems and it certainly points out one of the flaws in the P39 design. One wonders why the AAF aircraft were not seemingly well prepped for the tests. I suspect that when the tests were conducted that a production F6F was not available. The Aleutian Zero, according to this book, had an unseemly end. In 1944 a SB2C, Helldiver, inadvertently taxied into the Zero and destroyed it from the tail to the cockpit. "The Beast" strikes again.

Gotcha. Agreed that a 50% failure rate is pretty high, even if it is allegorical. Depending on where the tests were done, it might've (and this all idle speculation) been the aircraft were all training birds that were just plucked off the line. Student pilots beat the crap our of an aircraft.

But that is a high number for failure. Didn't think the Allsion was that bad of an engine. Always heard it was fairly reliable.