Impact of the R4M if it was ready earlier?

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Sid Guttridge
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Re: Impact of the R4M if it was ready earlier?

Post by Sid Guttridge » 30 Aug 2021 08:20

Hi Danebrog,

Thanks. From that it appears that the Germans only really got into the development of these rockets after August 1944.

If so, this rather undermines the original premise of this thread: "Now what would have happened if the development of this weapon was accelerated from 1942 onwards and it was ready for mass production by the beginning of 1944?"

Cheers,

Sid.

Tom from Cornwall
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Re: Impact of the R4M if it was ready earlier?

Post by Tom from Cornwall » 30 Aug 2021 11:29

Sid Guttridge wrote:
28 Aug 2021 17:11
The silly thing here is that much of this hot air is probably unnecessary, as this is to some degree empirically resolvable.

There were, it appears, a number of R4M attacks actually delivered. All that would appear to be necessary to gauge their effectiveness is for someone to marry the after action reports by the German attackers to the after action reports of the USAAF defenders.
Hi Sid,

I've been looking at some RCAF ORBs for 31 March 1945 and there is some evidence on use of "rockets" by Me 262 jet fighters and also of RAF/RCAF losses. The challenge, as ever, in these kind of discussions is to sort out claims against losses against evidence of loss cause.

I'll do a bit more digging and come back with a fuller response. But in essence the standard argument which seems to be given in an "earlier or more numerous wonder weapon" thread is that the Me 262 drivers claimed "x", the RAF/RCAF lost "less than x" therefore all those losses must have been caused by R4M. It's the same argument for Tiger "kills" in Normandy, etc.

There is some evidence from the ORBs that Me 262s attacked, and at least one mention of "rockets", I've also found another website that has a survivor's account from one of the lost bombers which mentions the cockpit being hit by a rocket which killed the pilot. The ORB's do, however, also contain strong evidence that two of the losses were caused by a mid-air collision between a Lancaster and a Halifax, and there is also sporadic mention of flak damage, other German fighters, etc.

I'll try to put together some more details and post them up next weekend.

I think what we have found so far, though, calls into question the veracity of this statement from the OP:
OTL during the last 2-3 months of the war the R4M AA rocket proved to be a higly effective and cost efficent Bomber Killer. Reports are sporadic and sometimes contradictory but it would seem that when just 20-30 German fighters armed with the R4M attacked a bomber formation of several hundred bombers, the Germans would lose a handfull of aircraft compared to several dozen Allied Bombers.
Regards

Tom

glenn239
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Re: Impact of the R4M if it was ready earlier?

Post by glenn239 » 30 Aug 2021 15:16

danebrog wrote:
29 Aug 2021 12:57
My very subjective opinion, what an earlier deployment of the R4M would have caused: The USAAF would have switched to night missions very quickly. And for this kind of highly specialized air warfare, the Luftwaffe and the armament industry of the Third Reich would have been completely overburdened.
What's your thinking why R4M's wouldn't work at night?

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Re: Impact of the R4M if it was ready earlier?

Post by glenn239 » 30 Aug 2021 15:24

T. A. Gardner wrote:
28 Aug 2021 19:05

You need a broadside deflection shot attack to make the R4M really effective. To make that attack effective, you need a lead computing fire control system or gunsight on the attacking plane. Without that, only a very practiced, highly skilled, pilot who knows how to deflection shoot using "Kentucky windage" (eg., by eye) is going to be effective doing this.
I literally had just posted the link saying that the tactic the 262's quickly evolved would fly line abreast and salvo their rockets in unison. By this method, all rockets are being aimed by the most skilled pilot in the formation, and the greener 262 pilots just have to maintain formation and press the firing button when ordered. However, any green pilot that flew in a wolfpack' attack was also being trained on deflection shooting for the R4M, so this just wasn't increasing the lethality of the 'experts' salvo, it was training green pilots on "Kentucky windage".
In any case, so far what we've read on the effectiveness of these rockets appears anecdotal rather than factual in terms of results. We can look at both side's claims and see that. Few if any bombers were shot down with them judging from the USAAF mission results.
The rockets were tiny and moving 500 meters per second. I think a bomber blowing up would look to other crews like a direct AA hit.

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Re: Impact of the R4M if it was ready earlier?

Post by Sid Guttridge » 30 Aug 2021 15:34

Hi glenn239,

Fighters tended not to attack the bombers in heavily AA defended zones for obvious reasons.

cheers,

Sid.

Tom from Cornwall
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Re: Impact of the R4M if it was ready earlier?

Post by Tom from Cornwall » 30 Aug 2021 15:44

glenn239 wrote:
30 Aug 2021 15:24
The rockets were tiny and moving 500 meters per second. I think a bomber blowing up would look to other crews like a direct AA hit.
At least one RCAF crew reported seeing a nearby bomber being attacked by “rockets” on 31 March 1945 which was, as far as I know, the first time Bomber Command crews would have seen them being used.

Do we know whether any were used at night? Bomber Command normally operated in a “stream” at night so not necessarily in a box formation that might suffer from “overs”.

Regards

Tom

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danebrog
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Re: Impact of the R4M if it was ready earlier?

Post by danebrog » 30 Aug 2021 20:48

glenn239 wrote:
30 Aug 2021 15:16
What's your thinking why R4M's wouldn't work at night?
The rockets would have worked just as well at night as during the day. However, the glare effect would certainly have been considerable.
But the real problem would have been to bring enough night fighters to the bombers - and there were already OTL quite significant problems.

As far as the actual use of the R4M is concerned: Due to the lack of documents, it is not possible to give exact figures on the number of machines equipped with it...very rough estimates are around 100 aircraft.
The rockets were apparently quite effective, but had no measurable effect at all with the vanishingly small number:
Hits were claimed, but they were demonstrably so few that they apparently caused the USAAF little headache.

The only photographically documented success with R4M that I know of is the B-24 "Red Bow" by First Lieutenant Rudolf Rademacher on March 4, 1945
http://www.jagdgeschwader5und7.de/oblt- ... ademacher/

Sid Guttridge
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Re: Impact of the R4M if it was ready earlier?

Post by Sid Guttridge » 31 Aug 2021 09:58

Hi Guys,

As I understand it, the Luftwaffe technique against bombers at night by 1944 was to home in on them by radar from behind. If nothing else, night time conditions probably made beam attacks very difficult to deliver.

Cherrs,

Sid.

glenn239
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Re: Impact of the R4M if it was ready earlier?

Post by glenn239 » 31 Aug 2021 15:08

Sid Guttridge wrote:
30 Aug 2021 15:34
Hi glenn239,

Fighters tended not to attack the bombers in heavily AA defended zones for obvious reasons.

cheers,

Sid.
Hi Sid,

True, and irrelevant to the observation that R4M hits might appear to be, and reported as, flak hits.

glenn239
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Re: Impact of the R4M if it was ready earlier?

Post by glenn239 » 31 Aug 2021 15:26

danebrog wrote:
30 Aug 2021 20:48
The rockets would have worked just as well at night as during the day. However, the glare effect would certainly have been considerable.
But the real problem would have been to bring enough night fighters to the bombers - and there were already OTL quite significant problems.
Agree on both points, but in terms of night attack with R4M the night fighter can approach closer and take a well aimed shot. There would be glare, but it's debatable that the rocket glare would be more significant to the safety of the fighter than the cannon tracers used in a regular attack.
The rockets were apparently quite effective, but had no measurable effect at all with the vanishingly small number:
Hits were claimed, but they were demonstrably so few that they apparently caused the USAAF little headache.
Yes, the system was introduced with only weeks left. In terms of effectivenes, against 4 engine bombers in large numbers, I would think that jets would be highly effective. Against escorting fighters they would be useless if the attacker were spotted, but probably somewhat effective in a 'bounce' situation.
The only photographically documented success with R4M that I know of is the B-24 "Red Bow" by First Lieutenant Rudolf Rademacher on March 4, 1945
http://www.jagdgeschwader5und7.de/oblt- ... ademacher/
I seem to recall that picture being credited to a direct 88 hit for the longest time.

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Re: Impact of the R4M if it was ready earlier?

Post by Sid Guttridge » 31 Aug 2021 18:11

Hi Glenn,

You post, "True, and irrelevant to the observation that R4M hits might appear to be, and reported as, flak hits."

Not entirely. Rockets could only be launched in the very visible presence of German fighters. If German fighters only tended to engage bombers where AAA wasn't present, why would Allied bombers assume that hits were due to AAA? Their default assumption would presumably be that it was the consequence of the fighter presence in such circumstances.

Cheers,

Sid.

Tom from Cornwall
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Re: Impact of the R4M if it was ready earlier?

Post by Tom from Cornwall » 31 Aug 2021 18:45

glenn239 wrote:
31 Aug 2021 15:08
that R4M hits might appear to be, and reported as, flak hits.
Or vice versa, obviously! Or in one case, a collision between two RCAF bombers is counted as two R4M kills as it happened on the right day!

Did LW Me 262s have gun cameras?

Regards

Tom

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Re: Impact of the R4M if it was ready earlier?

Post by danebrog » 31 Aug 2021 19:59

The entire development of cannons and rockets was primarily to combat American bomber pulks during daylight:
Preferably, the interceptors were to remain out of range of tremendous defensive fire. Or, at least, the dwell time should remain as short as possible. This led to the introduction of 3-cm and 5-cm guns, WGr 21 and R4M rockets

For night hunting, the problem never existed in this form. With the comparatively small speed differences and always very short combat distances, the 2-cm guns were completely sufficient for a kill until the end. Here it was much more important to find the target at all, which is why the focus was on the development of efficient radar, ECM, ECCM, and IFF systems.
In general, the requirements regarding technology, equipment and training were much more demanding than for day hunting.
(Hence my opinion that a change of the USAAF to night attacks would have completely overtaxed the Luftwaffe: It was already at the limit of its capabilities against the RAF alone.)

With the extremely fast flybys of the 262s, it was certainly extremely difficult for Allied crews to determine exactly whether a bomber was shot down by a concentrated cannon salvo or by rockets - the extent of destruction was probably quite similar in both cases.

From many years of experience I can say that reports from and about air battles are quite unreliable. This is certainly due to the stress and chaos of air combat.
Toward the end of the war, however, a relatively widespread phenomenon occurred on the German side:
When the war was lost for any halfway rational thinking person, quite a few soldiers wanted at least a Knight's Cross shortly before the end by issuing completely exaggerated claims (be it airplanes or tanks).
For propagandistic reasons and to strengthen morale, such heroic tales were then often taken over by the higher authorities completely uncritically and medals were distributed very generously.

The fact that the documentation situation on the German side towards the end of the war is abysmally bad makes it quite difficult today to distinguish fact from fiction.

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Re: Impact of the R4M if it was ready earlier?

Post by danebrog » 31 Aug 2021 21:15

Entries chief of technical air armament (Chef d. Technischen Luftrüstung/TLR) regarding development R4M:

27. Dec. 1944
Series preparation for R 4 M on-board missiles pushed ahead. Deployment of some 1O OOO targeted for front-line use in February.
28. Jan. 1945
Shortage of detonators. Preliminary planning for February: 25 OOO.
05. Feb. 1945
Run-up to shortened requirement (75 OOO pieces) can take place at short notice, material situation clarified.
05.March 1945
R 4 M propellant chamber production had to be changed again. Since manufactured propellant chambers cannot be used, large-scale production will not start in March as planned. The operational aircraft will be supplied by selected ammunition and laboratories at the development company. Securing of 5O % of production by underground (production) transfer to "Mittelwerk" in preparation. Production of the final rail for R 4 M has started.
25. March 1945
Meeting in Carinhall with Mr. Reichsmarschall. Installation of as many R 4 M as possible in the aircraft. As a quick fix, development of the 48 mount for the 8-262
16.March./4. April
The R 4 M on-board rocket was used by the troops in the month under review. Excellent shooting results were achieved with it.
(...)
Production expected to be severely impacted by western front situation, as drives are only manufactured in the Horn area. Other companies only just starting up.

Source: https://www.cdvandt.org/KTB-Chef-TLR-Be ... lorian.pdf

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Re: Impact of the R4M if it was ready earlier?

Post by danebrog » 31 Aug 2021 23:59

MACR for Rademacher's kill. The eyewitness accounts are interesting: none mention missiles....
However, no parachutes were reported either, although Radio Operator, Technical Sergeant Charles E. Cupp, Jr. did survive.
So it can be assumed that the evidence for this comes from Rademacher himself.
MACR 1.jpg
MACR 2.jpg
The problem are the totally insufficient original documents: There are wild rumors even in serious library literature about enormous kill numbers (up to 500), which were allegedly achieved with the R4M, which, however, with absolute certainty do not correspond to the reality of spring 1945:
Out of about 1200 262s built, only a small number ever reached the operational units, and about 60 of these were said to be equipped with R4M. The preserved documents about the actually operational aircraft of JG 7 are also very informative in this respect.
Logically, therefore, only a few individual successes could have been achieved with these rockets.
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