Why the USAAF gave up on the A-36 in favour of the P-47.

[tcolvin]

You tell me, Nick.

I thought the Spitfire IX (416mph) could not compete with the TA-152 (472mph), and was superseded by the Spitfire Mk XIV (439mph) and Tempest V (435mph), which had also replaced the Typhoon (412mph).

But I agree of course that it was fighters that seized command of German airspace.

Some of these same fighters when fitted with air brakes and bombs could also have turned the lights out in Germany and ended the war before D-Day by destroying the 90 large electricity generating stations on which German war production depended. This strategy would have been cheaper and more certain of success than the alternative of trying to destroy the largest 100 German cities.

Tony

[Kutscha]

There was less than a dozen Ta152Hs operational at any one time. It was only above 40,000' that such speeds were achieved by the Ta152H and even then it required GM1 to do so. At sea level it was slower than the Spit IX and had a lower climb rate > up to 1500fpm less.

The Tempest hardly replaced the Typhoon in squadron service with only 4 of the 30 Typhoon squadrons converting to Tempests.

Now that is an interesting concept. Use war weary a/c in the high stress dive bombing role. Not hard to miss the target when one is a lawn dart.

Yes be sure that 250lb or even 500lb bomb dropped by a single a/c could destroy power station complexes. How were these converted fighters to fly into German airspace before D-Day when they could not even reach the German border without carrying drop tanks?

Graham, Spit XVIs had rear fuselage fuel tanks. These were fitted initially in late 1944.

[tcolvin]

Kutscha; your comments reveal misunderstandings.

1. Agreed, that since there were so few Ta152s, and little petrol, nothing much mattered any more.

2. 2TAF did not operate "war-weary a/c", but rather obsolescent designs.
The Typhoon was designed as an air-superiority fighter, and replaced in that role by the Tempest V. But instead of shutting down Typhoon manufacture, the Typhoon IB continued to be built as an inaccurate fighter-bomber for the reasons given by the RAF - stable platform, reliable, big lift, infrastructure in place, etc, etc. Retired air-superiority fighter is surely the right description. RAF convenience trumped military need. The interesting question is how the RAF managed, and still manages, to get away with it.

3. You can be sure that 250lb and 500lb bombs could destroy 'power station complexes' with catastrophic results for the Germans, because the Strategic Bombing Survey said so. Destruction of the five largest German stations would have removed 8% of installed capacity; 45 plants 33%; and 95 plants over 50%. As little as one 500-lb bomb per acre of plant area would have disrupted operations for months, and 1,000 lbs of bombs per acre put the plant out of operation for 6 months to a year or longer. All these tonnages are in the Strategic Bombing Survey, which stated that, “all evidence indicates that the destruction of such installations would have a catastrophic effect on Germany’s war production.” The reason why electricity generating stations are peculiarly vulnerable to small bombs is because it takes only a small shock to disturb the rotor on its bearings, requiring plant shutdown until the bearings are repaired/replaced/re-balanced. The consequences of instantaneous removal of a power station is a nightmare for balancing the load within the distribution grid. And remember, once the Ruhr, or any of the other grids, had been brought down, any attempt to re-start could have been detected by aircraft fitted with equipment to detect the electro-magnetic radiation of the high voltage transmission lines, and triggered the return of the dive-bombers. The Germans could not have won this battle.

Tony

[tcolvin]

Thank you, Graham.

I would only make the point that it is not my repetition that makes "the divebomber .. the best solution for air-to-ground in all circumstances", but the fact that the dive-bomber was uniquely accurate in an environment where a near miss didn't cut it, and was worse than useless because it wasted scarce resources.

Tony

[drgondog]

Originally Posted by Kutscha

Yes be sure that 250lb or even 500lb bomb dropped by a single a/c could destroy power station complexes. How were these converted fighters to fly into German airspace before D-Day when they could not even reach the German border without carrying drop tanks?

Graham, Spit XVIs had rear fuselage fuel tanks. These were fitted initially in late 1944.

Kutscha - technically the P-51B-7 or its modified equivalent B/C could perhaps reach Hanover and Brunswick/Kassel and maybe Freiderichshafen radius with 500 pound bombs on the internal fuel including the 85 gallon fuse tank. Certainly could make it with one 500 pounder and one 75 gallon tank.. Ditto P-38J - both of which in ops prior to May 1944.

Having said that, I have no idea what percent of the Electrical Power Generation plants coud be reached.

[Juha]

Hello Tony
Again I have difficulties to understand Your thinking. There was no need for A-36s, what was lacking was the deep understanding of Germany’s electrical grid. There had been attacks on German power stations but if there has been will to all out attack on power stations, it could have been done with Mosquitos and P-38s if you think that heavy bombers would not hit anything. Mossies could destroy big houses as were shown in numerous cases and P-38s could carry one or two 750lb bombs depending of range needed.

Glider bombing wasn’t so inaccurate, here in Finland Maj. Luukkanen got 4 out of 4 50kg practice bombs inside a 20x30m target in his second try, F/Sgt Tani 2 out of 4 in his first try. They were fighter pilots flying Bf 109Gs. That was in training but with minimal practice.

Juha

[tcolvin]

You may be right, Juha, about the accuracy of glider bombing, but from my knowledge of what actually happened on the battlefield in February-March 1945, 2TAF could not do it effectively. However, that may be explained by the politically correct attitude of the RAF brass in never getting close to the army (evidence the crap thrown at Broadhurst for doing so) and their poor equipment - never let it be said 2TAF pilots were the problem.

Previously I have suggested Mosquitos could have done the job of taking out the German electricity generating system - 2 engines, 2 crew.
But that was before I understood what the A-36 could achieve with 1 engine, 1 crew, at half (?) the unit cost of a Mosquito, whilst providing more accuracy and offering a smaller target to the defence.

Your suggestion, however, that a deep understanding of Germany's electrical grid was missing is not borne out by the facts. Please forgive me for copying part of something I wrote several years ago on this subject. Today I would substitute the A-36 for the Mosquito, and place less emphasis on electronic navigation since in clear skies pilots could easily find a generating station - and even in cloud since cooling towers produce a tell-tale bump, although you can't always dive-bomb through cloud;

The third priority after surviving Hitler’s invasion attempt - even easier to repel as a result of strengthening the Admiralty - would have been to endorse not area bombing but the objectives laid down in the US AWPD-1 of August 1941. These were disruption of the enemy’s electrical power system, their transportation and oil & petroleum production. The intermediate objective of AWPD-1, however, which was the establishment of air superiority over the Reich through destruction of the GAF, would have been rejected as unnecessary. Instead a thousand DH98 Mosquitos, which first flew in November 1940 with production starting in July 1941, should have been ordered. Until the arrival of jets, this ‘wooden wonder’ was unstoppable and carried four 500-lb bombs. These would have been placed accurately by the new navigation devices such as GEE, which began service trials in July 1941; H2S with first trial at end 1941; and Oboe, first tried in the summer of 1942 and very accurate up to 270 miles from Britain but able to control only one bomber at a time. Oboe was first used against a Dutch power station in December 1942. The first operational sortie by a Mosquito was made on May 31, 1942 on Cologne. The right target would have been the electrical generating and distribution system as laid down in AWPD-1 but never made a priority target. The Mosquito fleet would quickly have eliminated the RWE and 20% of total electrical generating capacity by the autumn of 1942. The large rotors in generating stations were vulnerable to bombs and their destruction would have prevented electricity transmission while destabilising the entire system. If repairs were made and transmission restarted, low-flying Mosquitos would have detected the electro-magnetic field and promptly shorted out the switchgear by dropping steel cables over the transmission lines before returning to bomb the generating stations. The Ruhr would have been shut down in exchange for the destruction of several hundred Mosquitos.

I even have evidence that the idea of taking out the RWE was alive in 1943 and being discussed by some aircrew, who couldn't understand the targeting of city centres. Butcher Harris, of course, dismissed with contempt everything except area bombing as "panacea targets".

Tony

[Kutscha]

A Lancaster could carry 14 1000lb bombs.



Or 6 2000lb bombs



So why waste a squadron of dive bombers when one Lancaster could deliver the same weight of bombs that would shake the earth more than a 500lber?

Then there is this load out of up to 18 500lb + 1 4000lb,



The German power system, except for isolated raids, was never a target during the air war. An attack was extensively debated during the course of the war. It was not undertaken partly because it was believed that the German power grid was highly developed and that losses in one area could be compensated by switching power from another. This assumption, detailed investigation by the Survey has established, was incorrect.

20/20 hindsight is so wonderful.

What you failed to mention Tony is those 95 plants produced 50,000 kw. or more, and those 45 plants produced 100,000 kw. or more. Naturally, all were in easy range of the dive bombers.

Another thing you failed to take into consideration was the German response to the first few attacks on the power plants.

How long would it take from the time pencil was put to paper for dive brakes till at least one squadron of a/c was operational? How long would it take to set up and produce the parts required for the dive brakes and what would you cut from production to facilitate the manufacturing of these components?

You may be right, Juha, about the accuracy of glider bombing, but from my knowledge of what actually happened on the battlefield in February-March 1945, 2TAF could not do it effectively. However, that may be explained by the politically correct attitude of the RAF brass in never getting close to the army (evidence the crap thrown at Broadhurst for doing so) and their poor equipment - never let it be said 2TAF pilots were the problem.

More likely from the stress of being under fire.

Though these are for the 190 and 109, they can be applicable to the Allied dive bombers.




BTW, shouldn't these dive bomb topics be in the WW2 General Forum.

[Juha]

Hello Tony
yes, there were accuracy problems with 2TAF fighter bombers, there were times during Normandy fighting when infantry declined fighterbomber support because they thought that the safety margin of 400y was wide and relied on field artillery instead, which they had plenty in hand. But IIRC it was universal that safty margin of air support was wider than that of artillery, saying nothing on mortars.

IIRC Israelis concluded around 1950 that P-51 was more cost-effective CAS plane than Mossie.

IMHO there was lack of deep understanding of Germany’s electrical grid or there was even deeper understanding on the technical difficulties to implement the grid plan, otherwise it would have implemented. Power stations were rather high on target priority lists in 39-40 at least and in Aug 41 there was a big (54 Blenheims) daylight raid against 2 big power stations near Cologne. British also had first hand knowledge in late 41 on the effects on bombs on power grid and on power stations thanks for the LW. I know that British studied carefully the effects of LW bombing attacks and draw conclusions but cannot recall their conclusions on the effectiveness of attacks on power grid and on power stations. Still in 44 the Allied decided to give priority to transport network and oil targets not to power grid, they had some reasons for that and that wasn’t Harris, who see also those targets as diversions from his main job. But BC did what was ordered and hit the transport and oil targets.

There were constant debate on target priorities and all kinds of ideas were floated, if those who thought that the electricity was the key could have ability to convince their superiors that they had the key and it would be practical option, they would have had good chances to have their idea implemented, after all the dam raid was made, even if they needed much modified Lancs for it, new type of bomb, much special training for the crews etc.

Juha

[Nick Beale]

Originally Posted by tcolvin

You tell me, Nick.

I thought the Spitfire IX (416mph) could not compete with the TA-152 (472mph), and was superseded by the Spitfire Mk XIV (439mph) and Tempest V (435mph), which had also replaced the Typhoon (412mph).
Tony

You only have to read some combat reports to see how seldom aircraft in action came even close to their maximum speed in level flight. For that matter the Me 262 could make 540 mph and look how many of them got shot down.

Fascinating though the type is, the Ta 152 was of almost zero significance, with barely 20 (IIRC) making it into service.

Yes the RAF brought in faster aircraft than the Spitfire IX but that is not the same as the Mk IX no longer being a viable type in combat - it was used in large numbers up until the end and I don't recall reading of any occasions where it was outclassed and massacred by the opposition.

As for the Typhoon, its use for ground attack was consistent with the Luftwaffe's conversion of the Schlachtgeschwader to the Fw 190 F and the USAAF's reliance on the P-47.