The best 2-engined bomber in 1944-45?

[Shortround6]

Did later designed medium (twin) engine bombers really have a larger bomb bay or more internal capacity?

A quick glance over specs of various well known mediums doesn't really strike me of superior bomb lifting capacity for those later and supposedly 'more advanced' bombers .....

Well, the A-26 might have only held 4000lbs inside but that could consist of two MK 13 Torpedoes (although the doors did not close). Or carriers for 56 fragmentation bombs or various combinations. 2 x 2000lbs, 4 X 1000lbs, 8 X 500lbs, 8 X 250lbs, 12 X 100lbs. The weight capacity may not have gone up but the volume and flexibility may have.

An A-26 can be looked at two ways. An A-20 with a lot more firepower (bombs and guns) or a B-25 with a LOT more speed. A-26 could cruise about 9mph faster than a B-25Js top speed.

 

[Denniss]

Do 217M can load 4 tons internally but only SD (4x1000), for the SC load max would be 2800 (2x1400)

Do you have a source for this? I only have a source for the E-2 stating 3x SD1000 or 2xSD1000 + 2xSD/SC500 and both loads (as well as 2xSD1400) are stated as exceeding the rear CoG limit.

 

[mhuxt]

Mhuxt,
thanks for the data, that´s solid data enough to justify a correction. From what I can tell, "Höchstzulässige Dauerleistung" is specified usually as "max. rich mixture" and "Sparleistung" -in it´s different variants as "weak mixture".

Max. cruise speed should be at a little less than 6000m from these tables (to attain the full benefit of 1.20ata rather than 1.19 ata at 6000m) Cruise speed may correspondingly be slightly higher (~5 km/h) but I´m not going to quibble on that. Noteworthy that range figures are with alarger than specified safety figure (consumption is given with 970 ltr/h instead of the 800 ltr/h from the engine manual, thus 21.25% rather than 15% specified in the table). Interesting.

Cheers, glad the info was useful.

The only other twin-engine bombers the RAF seems to have been operating with any regularity in 1944 and 1945 were the Mitchell and the Boston, both with 2 Group in 2nd TAF.

 

[Shortround6]

I think Wellingtons were still in use in the Med and/or Far East.

 

[Vincenzo]

Do you have a source for this? I only have a source for the E-2 stating 3x SD1000 or 2xSD1000 + 2xSD/SC500 and both loads (as well as 2xSD1400) are stated as exceeding the rear CoG limit.

the source it's this PALBA.CZ • Zobrazit téma - Dornier Do 217, read on K-1 description and use a translator if like me don't speak czech
the max load with SC was 2x1800kg i was wrong in previous topic,


we (the forum) had the abwurfwaffenanlage here http://www.ww2aircraft.net/forum/other-mechanical-systems-tech/new-do-217-manuals-thread-5141.html but i can't speak Deutsch so i don't know if this confirm the palba web page

 

[mhuxt]

I think Wellingtons were still in use in the Med and/or Far East.

Very true, I stand corrected.

 

[Sydhuey]

for me it has to be the A-26, longevity of service, multi role , weapons load, multi environment (arctic to desert to tropics), able to take punishment in airframe and radial engines , it was designed to replace 3 (A-20, B-25,B-26)and supliment 1 (P-61 if it failed) aircaft, was to replace multple aircraft in RAF service if war continued (A-20 Boston,Baltimore, B-26 Maurader, B-25 Mitchell, Ventura, Wellington (Med theatre) Mosquitos were for europe, Mosquito was an absolutly fantastic aircraft but in europe never was good in Desert or Tropics (eg the RAAF got the Mosquito to replace the Beaufighter the Beaufighter out lasted the Mossie in RAAF service as it was not as durable being wood .....it literaly fell apart as told to me by some old boys who worked on both after the war), Russian aircraft not in hot climates, even today operating Russian aircraft in hot /tropical places , no ventilation ( you are in a flying sauna)

 

[tomo pauk]

What were the experiences of the in-topic plane (Tu-2) in hot climates? You do know that steppes in Southern Russia and Ukraine can have 35°C in summer?

 

[Sydhuey]

Undoubtedly it gets hot there, but 35 is an average day in the tropics and desert, the other 11 months a year its cold , just from my experiance with Russian vehicles and aircraft they are build for the cold not the heat, if the TU2 was tropicalised , filters , cooling ducts for engines , smaller spinners to increase airflow into engine not restrict it, cooling and ventilation in cockpit it would probably be better than the A-26 , but like the Mosquito is the choice aircraft for europe for moderate to cold climates, even today most aircraft are build to and operate in ISO conditions (15oC) and talk about hot and high performance at ISO +5 or +10 or +15 which covers Europe and North America, in Most of Australia ,the Pacific and Africa 15oC is a cold winters day, its hard to compare all these aircraft in all environments, each country build there aircraft for the role in there part of the world, the TU2 and Mosquito are probably the best twin multi roles in Europe but give me a A-26 in the rest of the world .

 

[wuzak]

longevity of service

Longevity of service is not relevant to a discussion on which was the best twin-engine bomber in 1944-45.

multi role

I would dispute that of the A-26, especially during the 1944-45 time frame. After the war and in later wars, maybe.

weapons load

In 1944-45 you are talking 4000lbs internally, which is what the Mossie could carry too. Granted the A-26 could hang a couple of thousand pounds under the wings - but that cost performance.

multi environment (arctic to desert to tropics)

When did the A-26 operate in the arctic? The desert?

Certainly the North Africa campaign was over before the A-26 was available, and before the Mosquito was available in sufficient numbers that they could be used outside the ETO.

If you are talking post war then the Mossie did serve in the middle east and in South East Asia.

it was designed to replace 3 (A-20, B-25,B-26)and supliment 1 (P-61 if it failed) aircaft

That may be so, but it doesn't make it the best twin engine bomber of 1944-45.

was to replace multple aircraft in RAF service if war continued (A-20 Boston,Baltimore, B-26 Maurader, B-25 Mitchell, Ventura, Wellington (Med theatre)

As far as I can tell the only aircraft it was going to replace in British service was the A-20/Boston.

Mosquito was an absolutly fantastic aircraft but in europe never was good in Desert or Tropics (eg the RAAF got the Mosquito to replace the Beaufighter the Beaufighter out lasted the Mossie in RAAF service as it was not as durable being wood .....it literaly fell apart as told to me by some old boys who worked on both after the war)

Now, you know that the last Mosquito in the RAAF served until 1953? As far as I can tell the last Beaufighter finished in 1946.

Also, the Beaufighter was not a bomber. This the roles for bomber Mosquitoes could not be done by a Beaufighter. The Beaufighter could not do PR work, at least not to the standard of the Mosquito. From what little I've read it seems that part of the reason why the RAAF didn't convert to Mosquitoes in SEA was due to slow deliveries, meaning they arrived to late for squadrons to train in them and join the war effort.

able to take punishment in airframe and radial engines

I suppose being a bigger, slower target would require the airframe to take more punishment. Not sure there is the evidence to prove that, though.

 

[Sydhuey]

Good replys don't agree with most but we all have our opinions
1/ longevity , yep didn't realy count in 44/45
2/light Bomber , low level strafer /Attack, Photo recon.
3/all the good ones very similar A-26/TU2/Mossie
4/maybe not arctic but it was Bloody cold in northern France end of 44 , Battle of the Bulge rings a bell coldest winter in years. Ok thats a one off, post war arctic weather service with USAF.
5/Don't think they designed an aircraft to be worse than these 3 !!
6/was ordered by RAF to replace existing types with 4 RAAF and 3 RNZAF sqns in europe(article XV sqns) (ETO and MTO), RAF changed their minds and they were earmarked to replace A-20's and B-25's with 88,342 and 226 Sqns, with there a/c going to MTO, with the MTO sqns getting subsiquent orders in 46 if war had continued on
7/yep last RAAF ops with Mossie 87 Sqn 1953, last target tug Beaufighter retired Mar 1956 with 30 TT(Target Tow) sqn so the first sqn in RAAF to operate the Beau was also the last.
8/matter of opinion, but the liquid cooled Merlins in the Mossie as any liquid cooled machine were always suseptible to damage.

I think all three the A-26 , Mossie and TU-2 were the outstanding twins in that time of the war , just depends on your opinion and were you want to use them .

 

[Shortround6]

In 1944-45 you are talking 4000lbs internally, which is what the Mossie could carry too. Granted the A-26 could hang a couple of thousand pounds under the wings - but that cost performance.

The A-26 may have had the same wight capacity but it could vary the bomb load much more to suit the mission. While a single 4000lb is NOT listed, two 2000lbs are, four 1000lb bombs, eight 500lb bombs.

Four 500lb could be carried under wing.

That may be so, but it doesn't make it the best twin engine bomber of 1944-45.

Because of it's size there some jobs it wasn't quite as suited for. But because of it's size and power there other jobs it could do rather well, like ground attack, with it's heavy forward firing armament. Glass nose versions had the option of replacing underwing ordnance with eight .50 cal guns. Ammo was in boxes mounted within the wing so pods only had to be sized to fit the guns. Perhaps not up to the Mosquito with four 20mm and four .303s but 6-16 .50 cal depending on plane and set up seems like a decent ground attack armament, and the bomb bay could still hold 4000lb of bombs.

I suppose being a bigger, slower target would require the airframe to take more punishment. Not sure there is the evidence to prove that, though.

Considering some of the uses the A-26 has been put to (fire fighting tanker) I think we can assume it was fairly rugged. Douglas was not noted for building flimsy aircraft. The plane carried a fair amount of armor and large panels oh hardened dural plate were used as combination skinning/protection from angle fire to extend the protection envelope.

See: Warbird Information Exchange • View topic - A-26 Invader Armor - Help!!!

 

[parsifal]

Now, you know that the last Mosquito in the RAAF served until 1953? As far as I can tell the last Beaufighter finished in 1946

.

Actually both answers arent completely correct. Both types were effectively retired in 1946, but a few of each were used in various specilaised roles for quite a few years. The last operational usage of a Beafighter that I know of in Australian service (not actually RAAF, it by then a DAP hack) was 1957, whilst for the Mossie it was 1962, for just one airframe, which had been gifted to a University squadron in Queensland.

Of the two types, undoubtedly the Mosquito was retained in greater numbers and was used more for operational purposes (for the most part aerial survey work and Operational Training) , whereas the Beafighter was used for flight school training and instruction mostly (including non-flying instructional airframes)

It is not valid to measure the ruggedness of either type on the basis of post war service, because in both cases their post war service was convoluted and cut short by the rapidly advancing technology.

 

[delcyros]

As promised, I reconsidered my approach.

BASIC CHANGES IN METHODOLOGY.

I keep the z-normalization to create relational units. I also keep the general rating, splitted up between offeensive (payload range), speed (see below) and general defensive (target size and power/weight ratio). Specific defense is not included, it´s determination requires an analysis by it´s own (it´s not measurable like the other entries) and I am limited in the time I can spend here. Of course, this selection maybe simplicistic and I am aware of the problem. Thus, please take the following as the outlines and explenation for my personal selection for the title "best late war twin bomber", rather than an attempt to authoritatively rank them. You may have different criterias than I followed here in this rather arbitrary and simple approach.
I change a bit the speed rating. Speed was earlier the only non-relational but compressed rating (created by an artificial starting point at 200mph). Thus, we know have three setups in speed rating:
[A] Top speed (boost speed at best altitude)
Cruise speed (sustainable cruise speed with bombs but w/o external stores as far as is known -not ferry range with all out fuel loaded)
[C] maneuvering speed realm (cruise speed minus (stall speed clean+10%))

PLANES.

I dismissed the swedish B-18 (a reasonable plane but not warproof). Added are
Do-217M, He-111H, Ju-188A, A-20G, B-25H, B-26G Pe-2FT
I also changes some entries based upon various sources pointed to me.

COMPARISON.

ASPECT 1. OFFENSIVE.
The most important asset of a bomber is to deliver a maximum of ordenance at pinpoint accuracy.
Since accuracy is a relative term dependent on crew skills it will not be touched by this comparison.
Note that I didn´t cared whether or not ordenance is be carried within a bombbay or externally as long as the airplane is capable to restore max. speed once the load is dropped.



The maximum ordenance to be dropped by a qualified twin engined bomber is 4t., to be shared between Do-217M and Tu-2S (=1.0 rating). Both, the He-111H, Ju-188A, A-26 and B-26 also have very credible payloads. This is not surprising as all four types doubled in the heavy bomber role occassionally. The 1 t. bombload of the Me-410A on the other end of the comparison is roughly one quarter as heavy as that of the two leading types (=0.25 rating, which is correct as four times 0.25 = 1.0 -true, four times 1t = 4t., z-normalization works).



Range also appears to be of fundamental importance for a bomber A/C. The japanese Ki-67 rules here. It follows a smooth transition, beginning with the He-111H and ending with the Ar-234B before - to my surprise, the rather short legged tactical twin engined bomber Pe-2FT follows.
The composite rating for this comparative offensive aspect is calculated as following:
rating= sqrt(payload*range)




For the offensive count, my choice is the He-111H, a good blend of payload and range (if You can afford the aerial superiority to expose this type of bomber). Followed by Tu-2S, Do-217M, Ju-188A and A-26. The last places are shared between Pe-2FT and Me-410A, the primary result of them beeing devoted to different types of attack under different tactical envelopes.


(to be continued)

 

[Shortround6]

I think you have seriously underestimated the B-25H. Either it carries more bombs or you have to give it it's true forward firing armament, eight. 50 cal MG AND the 75mm cannon. I would also be a bit leary of of the He 111 and a 4 ton bomb load. Same goes for the TU-2S. They may get off the ground with such loads but their operational radius is might short compared to their "normal" range.

Like the B-17. Some of them could carry over 17,000lb of bombs but they would be lucky to reach the coast of France and get back to England.

 

[delcyros]

II SPEED RATING

The Top Speed is for me considered to be an primarely defensive asset. Bombers may be forced to drop their load in emergancy in order to attain the maximum speed possible. The advent of the jet engine greatly benefitted the Ar-234B in this regard, whiches top speed of 461mph is only little slower than twice the maximum speed of the old´He-111H:



Both, the Mosquito and the Me-410A are significantly faster than the bulk of the other bombers, except for B-26, B-25 and He-111H, which are distinctly slower than the bulk of them.




The cruise speed, however, is a general asset of the bomber (in my personal opinion, cruise speed is to often underscored in these types of comparisons), again demonstrating the superiority of the jet engined bomber over it´s piston engined competitors. The difference is more marked with the jet driven Ar-234 beeing able to cruise at twice the speed of the B-26 (!), making sort of intercept very difficult. Both, Pe-2FT and Me-410A are also cruising very fast (for a prop), beeing bested by the Mosquito B.Mk XVI and Tu-2S fourth.

I have attempted a stall speed comparison but owing to a lack of valid data, this part is intentionally left open for a later time.

The composite rating once again = sqrt(topspeed * cruisespeed)



Unsuprisingly, the jet engined Ar-234B holds a tempting superiority and is able to cruise among the top speed of many single engined piston fighters of the day. The 2nd place goes to the Mosquito B.Mk. XVI, depending on whether You prefer top speed or cruise speed ratings with a very close fellow third, the Me-410A. On the other end of the scale, no difference can be found between B-25 and B-26 with the He-111H beeing the slowest all-around- bomber of the day.

 

[delcyros]

I think you have seriously underestimated the B-25H. Either it carries more bombs or you have to give it it's true forward firing armament, eight. 50 cal MG AND the 75mm cannon. I would also be a bit leary of of the He 111 and a 4 ton bomb load. Same goes for the TU-2S. They may get off the ground with such loads but their operational radius is might short compared to their "normal" range.

Like the B-17. Some of them could carry over 17,000lb of bombs but they would be lucky to reach the coast of France and get back to England.

to be corrected to 5000 lbs from the Boing manual. It´s late already here.

 

[wuzak]

What are you using for cruise speed - max range, max weak mixture, max continuous?

 

[delcyros]

I used the aequivalent to "max rich mixture". Please notice me if You encounter a problem.

 

[wuzak]

So, what is that in mph for each?