DH Mosquito, daylight bombing offensive?

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I got my hands on the "Germany and the Second World War" volume on strategic bombing during WW2 and it raises an interesting What If about the DH Mosquito being fast and accurate enough to survive and hit precision industrial targets in Germany by day. Was this even possible in terms of accuracy? In terms of surviveability by day apparently the Mosquito, due to it's wooden structure and resulting low radar signature (also a function of the Germans using longer wavelength radar that couldn't pick them up well) as well as speed made it very surviveable even against the single engine fighter defenses of German at altitude. For longer range missions where the target was somewhat obvious they did suffer during daylight, but against say the Ruhr small groups of Mosquitos appear to have suffered low losses historically even by day. The Fighter-Bomber variant was even able to tangle with and win over even Fw190s:
https://en.wikipedia.org/wiki/De_Havilland_Mosquito#Fighter-bombers


As to the bomber model:
https://en.wikipedia.org/wiki/De_Havilland_Mosquito#Bombers
https://en.wikipedia.org/wiki/De_Havilland_Mosquito#Operational_history


https://en.wikipedia.org/wiki/De_Havilland_Mosquito_operational_history#RAF_bomber_operations


Could it have made a precision daylight bomber from 1943 on and done more cheaply and effectively what the USAAF was trying to do and achieve the RAF Bomber Commands mission at a fraction of the cost all around?


I used to work with an oldboy who was a flight engineer on a Lancaster during the war

I suggested to him that it must have been a terrible experience - he shrugged and said they in 40 odd missions his aircraft never got shot at and that his Brother was in the Army and had had a much worse time of it at Monte Cassino!

Point taken!

He also said (and this has stayed with me) that in many of the post mission briefings they were congratulated on their efforts etc and told that - PR Mosquitos had photographed the target - returned back to the UK before the Bombers had all returned - the analysis would show that the target had been damaged but its okay because we sent a couple of Mossie Squadrons to finish it off!

His opinion was and remained - "Why didn't they send the bloody mossies in the first place"

I seem to recall (and this is dredged up from the old grey cells) that a Lancaster squadron would land 2 out of 14 bombs within the target area while a mossie would on average land 2 out of 4!

For my part I have always maintained that the unarmed bomber variant of the Mossie was a better bomber than the Lancaster and other 4 engined types and that if 2 Mossies could have been built for each Lancaster (or other 4 engine bomber) then a very comprehensive and less expensive day light bombing campaign could have been maintained.

And not to mention that a Mossies crew was a Pilot and Bomb Aimer/Co-pilot meaning that in the harsh realities of war a Mossie that was shot down only resulted in the loss of 2 crew while the Lancaster/Stirling etc would lose 7

This would have freed up 4 engine AC for maritime ASW patrols and other duties.

However as this is the internet there are several potential issues with this idea - and I am not sure of the Answers!

Was there enough wood of the correct type used in the laminate wings to build more Mossies than were built OTL?

While we know that there would have been enough Engines - would there have been a limit to the number of Radios, Bomb sights and other 'hi-tech' equipment?

And also while we know there was enough Pilots to allow the Mossie to replace the larger 4 Engine Aircraft on a 1 for 1 basis - was there enough to replace each heavy bomber with 2 Aircraft?

Lastly while the mossie was undeniably 'better' at delivering bombs as has been mentioned it carried just over a quarter of what a Lancaster could carry - so for missions such as Dropping incendiaries or very large bombs the 4 Engine bomber is superior (however large numbers of Mossies' might make such tactics unnecessary in the first place?)

But in answer to the OPs question had the RAF managed to replace each heavy bomber with 1 or even possibly 2 Mossies from 1943+ then this does not bode well for the Axis and I think that such a change would have resulted in a large change to the daylight bombing campaign with greater accuracy and lower losses by the allied Bomber Commands and greater damage to the German War industry.
 
I know that OP suggesting the daylight bombing offesive by exclusively-Mosquito force, but what about doing the same by night? That removes German night fighters from equation, and almost does the same with light Flak?
 
It is worth adding that as aircrew became available mossies were doing two Berlin raids in a single night with two crews. So for four aircrew and one aircraft you get two 4000lb cookies delivered. Whereas a Lancaster IIRC was a crew of 7 for a max load of 14000lb, not sure if that load could be carried to Berlin though.
 
The Mosquito was made of wood laminate which helped save aluminium.

If we are building theminstead of (or at least instead of part of) the Lancaster force, why cant we make them in metal?
Or perhaps the OTL wood/Merlin version, and a metal/griffon version (which should be even faster).

They would be easier to track on radar, but if they were faster there is a reduced interception window, so things could cancel out.
 
That at least means fewer aircrew for the RAF Bomber Command, but it sharply reduces its bombardment ability. There are most definitely trade offs here. However the Sterling, Halifax and Wellington do have uses. They could serve in the CBI and they are needed for Coastal Command.
.

snipped - pedantic nitpick - RAF Bombers had a habit of being named after towns/cities, as in Wellington, Halifax, Lancaster, Bombay, Harrow, Henley, Battle etc., Shorts too made a bomber which was named after a Scottish city called Stirling - sadly, it seems too many confuse it with the British currency - Pound Sterling.
 
It is worth adding that as aircrew became available mossies were doing two Berlin raids in a single night with two crews. So for four aircrew and one aircraft you get two 4000lb cookies delivered. Whereas a Lancaster IIRC was a crew of 7 for a max load of 14000lb, not sure if that load could be carried to Berlin though.

Lancaster was good for 1660 miles of range with 14000 lb bomb load.
Excellent site helps a lot: link

Re. extra crew: one of 1st things Harris did was to cut number of pilots per aircraft from two to one, thus doubling the pool of pilots.
 
But Mosquitos put their ordnance on target much more accurately. The Lanc and other heavies were kind of a shot gun approach to bombing and were only advantaged in terms of area targets like city centers (or major oil facilities like Leuna that were city center sized), while smaller industrial targets were more accurately hit by Mossies in small groups with small payloads with limited dispersion; the heavies had major dispersion of their ordnance, so most was generally wasted just by how much was being dumped all at once. Like with B-17s operating by day (more accurately than the British heavies), they found that after the master bomber dropped his loads the rest of the bombers didn't aim and just dropped as soon as they saw the master bomber dropping, while following on groups found the target obscured by smoke from the previous bombing runs; most of the heavy payloads then used on industrial targets were wasted and scattered all over the place because they either couldn't see the target, didn't air properly, or the sequenced release of multiple bombs carried them outside the aiming point due to delayed release action. Against non-area targets the dispersion inherent in heavy bomber payloads in large groups made they wildly inaccurate and the vast majority of their payloads a total waste. If a Mossie could put all four 250kgs on target, but the Lancaster could only put 500kgs out of 6000 or more on target, the Lanc is a waste of explosives, crew, aluminum, etc. compared to the lighter bomber.

Much of the accuracy issue would appear to be a function of number of aircraft/weight of bombs/crew skill rather than aircraft type.

Small groups bomb better because there's less smoke; Mosquitos are more accurate because the crews are more trained/experienced in "precision" bombing; accuracy of a Mosquito and Lancaster bombing from high altitude, all other things being equal, should be the same.

So this is less an issue of aircraft type and more one of aircraft use and crew training.
 
To repeat a point. The UK had plenty of aluminium for airframes. Bauxite from Jamaica in particular and hydro electricity in Scotland developed for the aluminium industry. The collection of scrap aluminium in Britain in WW2 was more about promoting public spirit than needing scrap aluminium.

The limiting factor in Mosquitos would be the supply of suitable balsa wood from Equador. Today it is plantation grown and in other parts of the world but WW2 production relied upon wild harvesting. The airframe being two thin plywood sheets sandwiching a balsa wood core. In aero use post war balsa wood cores were sandwiched between aluminium sheets in products like Mallite and demand is still high.

Today one has foam or resin honeycomb sheets and sheet film glues to let you use alternatives but only balsa wood was available in sufficient lightness, glue compatability and ease of use for the Mosquito task. Ironically the plywood sheets would be easier to replace with a flax reinforced phenol-formaldehyde resin matrix like Gordon Aerolite from which a satisfactory experimental Spitfire fuselage was made early in the war. Or by aluminium when phenol–formaldehyde/polyvinyl–formal adhesives like Redux of Aero Research Ltd, as used in the DH Hornet wings, could bond to wood or metal but that would only be at the very end of the war.

So if any aeroplane made in wood in the UK during the war could have a metal alternative that would be a way to release wood production capacity for the Mosquito, as long as all the balsa production in Ecuador could meet the demand. 1942 would be too late to exploit other growers who would lack the infra structure to extract and kiln dry it. Nowadays balsa plantations are being expanded across the globe with planned infrastructure but in the 1940's you only have wild timber that grows in forest clearings.
 

Deleted member 1487

Much of the accuracy issue would appear to be a function of number of aircraft/weight of bombs/crew skill rather than aircraft type.

Small groups bomb better because there's less smoke; Mosquitos are more accurate because the crews are more trained/experienced in "precision" bombing; accuracy of a Mosquito and Lancaster bombing from high altitude, all other things being equal, should be the same.

So this is less an issue of aircraft type and more one of aircraft use and crew training.
By day they could see better and survive lower level strikes, while at night they were OBOE and later Gee-H guided, which were more accurate than even using bomb sights by day. Training was certainly part of it, but then all this speaks to things being achieved better by fewer, smaller, better trained bombers and their crews. Keep the heavies for special tasks, like using the special bombs and flattening Leuna by night with Pathfinder guidance.
 

Deleted member 1487

So what changes would a metal Mosquito have to make structurally?
 
The bomber offensive would be waged by the general bomber, not the bulged 'cookie' bomber, except for special missions.

So long-nacelle, two-stage blown merlins, standard RAF bombsight, 4 x 500/1000lb bombs doing 380-410mph at altitude but dropping bombs from maybe 20,000' for accuracy?

What is the bombing CEP of Mozzies operating in this fashion? What was the loss rate per mission?

I think that before we start talking about production rates and all that crap we should know exactly what was technically possible, because the standard bomber Mozzie isn't going to be doing low level bombing missions on Gestapo HQ.
 
The Mosquito was made of wood laminate which helped save aluminium.

If we are building theminstead of (or at least instead of part of) the Lancaster force, why cant we make them in metal?
Or perhaps the OTL wood/Merlin version, and a metal/griffon version (which should be even faster).

They would be easier to track on radar, but if they were faster there is a reduced interception window, so things could cancel out.

Well the proposed Hawker P.1005 needed two engines in the 2,000hp range to get 400mph at 25,000ft, admitedly a larger aircraft at Span 70.0ft, length 54ft (est 51ft as a fighter), wing area 677 square feet, max weight 31,255lb (34,000lb overload) but it gives an indication of the engine power you would need for a metal Mosquito.
 

Deleted member 1487

So long-nacelle, two-stage blown merlins, standard RAF bombsight, 4 x 500/1000lb bombs doing 380-410mph at altitude but dropping bombs from maybe 20,000' for accuracy?

What is the bombing CEP of Mozzies operating in this fashion? What was the loss rate per mission?

I think that before we start talking about production rates and all that crap we should know exactly what was technically possible, because the standard bomber Mozzie isn't going to be doing low level bombing missions on Gestapo HQ.
If OBOE guided even higher flying Mossies got within 35m. This link says 10 yards:
http://www.qsl.net/pe1ngz/stories/story-oboe-h2s.html
The two men operating the system could release a bomb with an accuracy of 10 yards which was greater than could ever be achieved by heavy bomber aircrew but the final result would depend upon the characteristics of the individual bomb or target indicator.

For Gee-H it was about 150 yards:
https://en.wikipedia.org/wiki/Gee-H_(navigation)
Gee-H achieved accuracy of about 150 yards at 300 miles.[5
Haigh 1960, p. 250.
  • J. D. Haigh, "Gee-H - AMES 100", The Services Textbook of Radio, Volume 7, Radiolocation Techniques, 1960

http://www.radarpages.co.uk/mob/navaids/geeh/geeh1.htm
With these refinements a range accuracy of the order of 20 yards was obtained at 200 miles.

https://en.wikipedia.org/wiki/De_Havilland_Mosquito_operational_history
Despite an initially high loss rate, the Mosquito ended the war with the lowest losses of any aircraft in RAF Bomber Command service. Post war, the RAF found that when finally applied to bombing, in terms of useful damage done, the Mosquito had proven itself 4.95 times more cost-efficient than the Lancaster.[2]

There were much longer, much more detailed posts here with links, I just did a short post:
http://www.warbirdsforum.com/topic/1545-bomber-losses/
I picked June 1944

Mossie - 7 lost in 1487 sorties for a 0.47% loss rate
Lancaster - 182 lost in 8614 sorties for a 2.11% loss rate
Halifax - 105 lost in 5095 sorties for a 2.06% loss rate

American heavy bomber, ETO - 520 lost in 28,925 sorties for a loss rate 1.798% (ref AAFSD)

http://www.warbirdsforum.com/topic/2153-some-mosquito-info/
A while back we had the stats for Mosquito losses on night bombing operations, from May 1943 to May 1945. This amounted to 106 lost and 88 damaged beyond economical repair, in a total of 26,936 sorties.

This gives a loss rate of 0.39%, a rate of 0.33% damaged beyond economical repair, a total of 0.72%.

REading Ian Thirsk's de Havilland Mosquito, An Illustrated History, Volume 2 I cam across an interesting statistic:
Mosquito bombers flew a total of 39,795 sorties during the Second World War, delivering 26,867 tons of bombs. Losses amounted to 254 aircraft, representing a loss rate of 0.63 percent, the lowest of any aircraft in Bomber Command

This means that in 12859 (presumably) daytime sorties there were 148 Mosquitos lost, at a rate of 1.15%. Not unsurprisingly, significantly greater than for night time operations. But still way below the loss rate of Lancasters (which flew mostly at night).

Fighter-Bomber Mossies could be used too for lower level or tactical strikes.
 
Well the proposed Hawker P.1005 needed two engines in the 2,000hp range to get 400mph at 25,000ft, admitedly a larger aircraft at Span 70.0ft, length 54ft (est 51ft as a fighter), wing area 677 square feet, max weight 31,255lb (34,000lb overload) but it gives an indication of the engine power you would need for a metal Mosquito.

Mosquito B.Mk.IX - 2-stage Merlins, can carry cookie and external 2x500 lb (speed 397 mph in that case; 408 mph at clean,).
Shortcoming - available by some time in late 1943, so let's have RR better churning out the 2-srage Merlins already in 1942.

If OBOE guided even higher flying Mossies got within 35m. This link says 10 yards:
http://www.qsl.net/pe1ngz/stories/story-oboe-h2s.html
For Gee-H it was about 150 yards:
https://en.wikipedia.org/wiki/Gee-H_(navigation)
http://www.radarpages.co.uk/mob/navaids/geeh/geeh1.htm
There were much longer, much more detailed posts here with links, I just did a short post:
...

Thank you for the excerpts. Are those numbers for position of an aircraft, or for position of the bomb once strikes ground?
 
If OBOE guided even higher flying Mossies got within 35m. This link says 10 yards:
http://www.qsl.net/pe1ngz/stories/story-oboe-h2s.html


For Gee-H it was about 150 yards:
https://en.wikipedia.org/wiki/Gee-H_(navigation)


http://www.radarpages.co.uk/mob/navaids/geeh/geeh1.htm


https://en.wikipedia.org/wiki/De_Havilland_Mosquito_operational_history


There were much longer, much more detailed posts here with links, I just did a short post:
http://www.warbirdsforum.com/topic/1545-bomber-losses/


http://www.warbirdsforum.com/topic/2153-some-mosquito-info/


Fighter-Bomber Mossies could be used too for lower level or tactical strikes.

As I expected the numbers are better than the 4 engine heavies, but is a 20 yard CEP enough to generate better operational results and can it be maintained in a larger and less specialized force?
 

Deleted member 1487

Thank you for the excerpts. Are those numbers for position of an aircraft, or for position of the bomb once strikes ground?
AFAIK the CEP of where the bomb hits on the ground for the 150 yard one and the 20 yard at 200km is open to interpretation, I'm assuming it means the position of the bomber over the target.

As I expected the numbers are better than the 4 engine heavies, but is a 20 yard CEP enough to generate better operational results
Oh hell yes considering that heaviest scatting bombers with a CEP of kilometers, not tens of meters. A smaller factory target would be in the 100s of meters, so a CEP of 20-150m is pretty much a guaranteed hit. If then you only need a few waves of the most most that could be guided by say Gee-H, 80 aircraft, you could well smash a factory by night. For larger targets like Leuna you'd need the heavies, say 200 or so with Pathfinder guidance using H2S and OBOE/Gee-H (Leuna is outside that range, but those systems would get them on the right path before H2S navigation took over). Of course using Mossies with cookies could do the same job....

and can it be maintained in a larger and less specialized force?
That's the rub. Of course given the highly specialized and skilled personnel used for Lancasters, I'd say yes. Especially when units like Group 100 become unnecessary because the bombers are uninterceptable by night (and often day).

All of the above leaves out day bombing too, which would be a factor with smaller units of Mossies. If needed they could be escorted later on by US aircraft, LL P-51s, or even the long range Spitfire that was never put into production, but was developed. Just imagine the nashing of teeth that would happen among Nazi high command when the wooden wonder smashes up their industry and they can't even touch them. Precision attacks on the electrical industry would have ground German industry to a halt too had they made the effort. The Mossie is the ideal aircraft to pull that off.
 
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You might be mistaken, since there was a glut of American and Argentine flax seed, and linen production centered in Belfast.
Quite possibly. I was only basing it on the Agricultural Guidelines issued by HMG which encouraged farmers to to grow flax for the first time to make up for loss of European flax. That's the only source I had, and may refer to an anticipated shortage, possibly filled from overseas.

Having said that, to feed the factories of Belfast, you'll need grown and processed flax, not seed.
 
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The timescales mentioned here (1943 onward) was also the time of the birth of the Guided Bomb, at least in Germany & USA. The Mossie in a high-flying daylight role would have been a perfect fit for such a weapon.

Imagine - 1940 - Churchill suddenly gets the idea (as he did with so many things) that a guided bomb would be a good idea & issues an "Action This Day" notice to cut through the bureaucracy. It's clearly do-able with the technology of the day.
 
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