Best medium bomber of WWII?

[fastmongrel]

There was a 3000lb bomb load stage, 2000lbs inside the airplane (four 500lb bombs) and one 500lb under each wing. Performance with underwing bombs didn't suffer too badly.

The 4000lb load was the single 4000lb cookie, it could not carry 4000lbs of smaller bombs. It was not used operationally until 1944.

I don't believe the British thought of the Mosquito as a general purpose bomber during the war but rather a special purpose bomber. Precision daylight strikes and pathfinder.

The idea that the Mosquito could be a general purpose bomber and replace a large number of the 4 engine heavies may be a post war or even internet idea?
Correction welcome in the form of air ministry memos or letters/minutes of meetings.

What is a definition of a 'medium bomber'?

I was thinking that myself. Isn't it more of a function or a role. The Blenheim carried out light bomber roles like Infantry support but also did medium bomber tasks like attacking the Ruhr.

 

[GrauGeist]

In all seriousness, though, the definition of "light", "medium" and "heavy" bomber is rather difficult to define.
Different militaries had a wide range of requirements, each being defined in their own wording.
Many countries had single-engined "light" bombers, but this classification overlapped to twin-engined types, too.
Once into the "medium" bomber class, there were a broad range of types that not only had two engines, but several with three engines as well.
The "heavy" class, seemed to apply to four and six engined bomber types.

Then there was the wide range of bombloads across all the types, with no real limit between each...

 

[tomo pauk]

The nomenclature chaged during the time, and each country have had it's separate nomencalture to begin with. Japanese called the G4M and other 'big' 2-engined bombers as heavy bombers.
My take is that this 'inquiry' needs to have the time span. Ie. what was the best 2-engined bomber between August 1939 and late 1941. Then - the best 2-engined bomber between late 1941 and fall of Italy. Etc.
Granted, not ideal, but might work better than a top-list that spans over 5 ww2 years.

 

[fastmongrel]

Just to be awkward I think the Mossie is in a category of its own. Best strategic light bomber that carried a medium bomber load from 1944.

 

[Dimlee]

The nomenclature chaged during the time, and each country have had it's separate nomencalture to begin with. Japanese called the G4M and other 'big' 2-engined bombers as heavy bombers.
My take is that this 'inquiry' needs to have the time span. Ie. what was the best 2-engined bomber between August 1939 and late 1941. Then - the best 2-engined bomber between late 1941 and fall of Italy. Etc.
Granted, not ideal, but might work better than a top-list that spans over 5 ww2 years.

Indeed, the number of engines does not change (mostly). While heavy/medium/light or long-range/middle-range or strategic/tactical/CAS - those definitions vary between the forces and countries and even within one airforce.
"Medium" B-25 became "long-range" in USSR.
Pe-8, the future backbone of planned (and never built) new strategic Soviet air force, was relegated to tactical tasks mostly.
Ju-88 was used in strategic bombing role in 1942-1943 against industrial targets in USSR.
The first raid of tactical and middle-range Pe-2 in the Black Sea was against Ploesti - the genuine strategic target located over 600 km away - which could be considered as "longe range" in the Eastern Front.
The only war assignment of strategic Tu-4 was to bomb a cinema house in Budapest in 1956 (canceled after the take-off).
Strategic B-29 was out of SAC in Korea.
B-52 has started its combat career in CAS role if I'm not mistaken?

 

[GrauGeist]

It would be quite a challenge to create a clear classification between the types - the Japanese considering the G4M as a heavy bomber (with a bombload of roughly 1,900 pounds), while the P-47 could heft 2,500 pounds of bombs, leaves one to wonder how their classification was determined.

 

[tomo pauk]

It would be quite a challenge to create a clear classification between the types - the Japanese considering the G4M as a heavy bomber (with a bombload of roughly 1,900 pounds), while the P-47 could heft 2,500 pounds of bombs, leaves one to wonder how their classification was determined.

Light bombers = 1-engined types, plus the Ki-48 (880 lbs bombload)? Anything 'better' with 2 engines being the heavy bomber?

 

[pbehn]

The idea that the Mosquito could be a general purpose bomber and replace a large number of the 4 engine heavies may be a post war or even internet idea?
Correction welcome in the form of air ministry memos or letters/minutes of meetings.

Well, it was a private venture, any documents would have to be before work was suspended and they asked for a turret to be put on it. In hind sight many branches of the allies could have used more Mosquitos but it wasn't clear at the time and there is a limit to precision bombing and also what a Mosquito could do.

 

[Greyman]

The idea that the Mosquito could be a general purpose bomber and replace a large number of the 4 engine heavies may be a post war or even internet idea?

The numbers were crunched several times by 'the brass' and the Lancaster was always the most efficient type in terms of tonnage dropped vs every factor.

The Mosquito was generally the closest to the Lancaster, but as pointed out in one of their papers:

In order to put down the same weight of bombs in a given time it would be necessary to fly many more Mosquito sorties than Lancaster sorties and thus a considerably larger force would be required. This would lead to the need for increased numbers of aerodromes, maintenance personnel and pilots.​

 

[Milosh]

The numbers were crunched several times by 'the brass' and the Lancaster was always the most efficient type in terms of tonnage dropped vs every factor.

The Mosquito was generally the closest to the Lancaster, but as pointed out in one of their papers:

In order to put down the same weight of bombs in a given time it would be necessary to fly many more Mosquito sorties than Lancaster sorties and thus a considerably larger force would be required. This would lead to the need for increased numbers of aerodromes, maintenance personnel and pilots.​

It would also mean the enemy would require many more interceptors.

 

[ThomasP]

I believe the Japanese called the G3M and G4M (both 2-engine) "land-based attack aircraft" in their specifications, not as light, medium, or heavy bombers. The G5N (4-engine), on the other hand, was called a "large land-based attack aircraft" and was capable of carrying ~3.2x the load of the G4M.

I think if we are calling the Wellington (2-engine, 4500 lb bomb load) a medium* bomber, then the G3M ( 2-engine, 2000 lb bomb load) and G4M ( 2-engine, 2200 lb bomb load) should be considered mediums as well. The G5N (4-engine, 7200 lb bomb load) should be classed as a heavy. In the Japanese AC cases it could perhaps be said that the smaller bomb load was a trade-off for very long range.

*At the time of the development of the Wellington, the AM Specifications that led to its heavy counterparts (Warwick, Manchester, Halifax) only required an 8000 lb bomb load.

 

[Koopernic]

I would have thought the Vickers Wellington:
1 It was there at the start of the war.
2 It had long range and high bomb load. So much so it pretty much outperformed the Shorts Sterling at long range.
3 It had good armament. (In theory 50 calibre guns could have been fitted).

-Aircraft like the B-25 and B-26 just weren't around in 1939,1940, 1941,1942 so although you might argue they were better in some way (certainly not speed, bomb load or range or toughness compared to Wellington) they simply weren't around.

-The Mitsubishi Betty kept getting improved and final versions hand laminar flow wings and self sealing fuel tanks.

-Ju 88 is a funny one in that it was more of a light bomber but was famous for being an excellent dive and slide bomber, torpedo bomber, night fighter, pathfinder etc. As a medium bomber it wasn't much but it was these other rolls that made it extremely useful and it was there from 1939 till the end of the war . It's hard to imagine the Luftwaffe having a fraction of success with something else.

-The Do 217 is an interesting one having used guided weapons such as Fritz-X and Hs 293 it also became quite a fast bomber (347mph for the Do 217M) and might have been quite hard to deal with if the Luftwaffe had the resources for a larger bomber force.

 

[GrauGeist]

Aircraft like the B-25 and B-26 just weren't around in 1939,1940, 1941,1942...

The B-25 and B-26 were both introduced into service in 1941.

 

[fastmongrel]

Interesting factoid about the Wellington the Blackpool Squires Gate factory built one in a day.
Great little film


Edit, I have just found out that the film was made not at Blackpool but at Broughton in Flintshire N Wales. Apparently my Great Aunty is in the crowd as the aircraft taxies away. I have been told off by my cousin for getting the family history wrong

 

[Maromero]

Ju 388

 

[Koopernic]

Ju 388

The Ju 88 roots were very clearly evident. Speed 388mph/625kmh with a service ceiling around 46,000ft with the BMW 801TJ1 and speed of 407mph/655 kmh with the Jumo 213E1 using MW50. With the Jumo 222E/F a speed of 444mph/715kmh was estimated. There were two more advanced versions of this engine on the test bed: the BMWW 801TJ2 and the BMW801TQ

As far as I know EK388 flew very few 'evaluation missions with the Ju 388L, it almost missed the war. The last 3 piston engine combat aircraft on the Luftwaffe production program when the war ended were the Ju 388, Do 335 and Ta 152. The wanted to be an all jet air force but the jets just didn't have the range or airfield performance.

An interesting spin of from the Ju 388 was the 4 engine Ju 488. They lengthened the fuselage, used the tail and twin tails and remote armament of the Ju 288, added a wing section and engine of the Ju 388 inboard to extend the wing to give it 4 engines. The resulting heavy bomber had a ceiling of 48500ft with BMW801TJ engines and probably would exceed 50,000ft.

Almost neared completion and a test flight.

 

[wuzak]

The original series (1 and 2) of the Mosquito were rated at 1,000 and 2,000 pound bombloads respectively.
It wasn't until the Mk.IV that a 4,000 pound bombload was incorporated into it's design - in 1943.

The series i and series ii were B.Mk IVs. The B.Mk IV series i had the short nacelles and the short span No 1 tailplane.

The series ii had the long span tailplane and the long engine nacelles that was common on all subsequent Mosquitoes.

Only 10 B.Mk IV Mosquitoes were built. They may have been restricted to 1,000lb only until the short tail 500lb MC bombs became available.

 

[wuzak]

There was a 3000lb bomb load stage, 2000lbs inside the airplane (four 500lb bombs) and one 500lb under each wing. Performance with underwing bombs didn't suffer too badly.

The 4000lb load was the single 4000lb cookie, it could not carry 4000lbs of smaller bombs. It was not used operationally until 1944.

I don't believe the British thought of the Mosquito as a general purpose bomber during the war but rather a special purpose bomber. Precision daylight strikes and pathfinder.

The idea that the Mosquito could be a general purpose bomber and replace a large number of the 4 engine heavies may be a post war or even internet idea?
Correction welcome in the form of air ministry memos or letters/minutes of meetings.

The "3,000lb bomb stage" came after the introduction of the universal wing, which coincided with the production of the FB.VI. This was in 1943.

Development to carry the 4,000lb bombs (4,000lb HC "cookie" and 4,000lb MC bomb) began in 1943 on the Mk.IV, and was applied to B.Mk XVI in production, after the first few were built. Not sure if the B.Mk IX had that conversion as well.

The maximum load for a B.Mk XVI was 5,000lb for short range missions - 1 x 4,000lb + 2 x 500lb on wings.

 

[wuzak]

Towards the end of the war there was a new system which carried 6 x 500lb inside the aircraft, presumably they could also carry the 2 x 500lb bombs externally, but if they ever did I have no idea

The "Avro carrier"?

In my (limited) research I have not found evidence of such a device.

However, I did find that there were plans to install a modified Wellington bomb beam into the Mosquito in order to increase the number of target indicators that could be carried.

The beam would have allowed the carriage of 8 x 250lb target indicators (target indicators came in 250lb and 1,000lb) inside the bulged bomb bay.

Inevitably the Air Ministry asked de Havilland if 8 x 500lb MC bombs could be fitted instead. The answer was that the bombs would fit, but the CoG would have been too far rearwards, and made the aircraft unstable. Perhaps the Air Ministry should have advocated for the removal of the IFF....

Further enquiries were made to the possibility of carrying 4 x 500lb forward and 4 x 250lb aft on the bomb beam. But I did not see any reply to this suggestion.

Some Mosquitoes were modified from the 4,000lb model to carry a single 1,000lb TI (same size as 1,000lb MC). Fewer were modified to carry 2 x 1,000lb TIs, from memory these were all for 618 Squadron.

Fun fact: if Little Boy had been fitted with a British style round tail rather than the US style box fins, it would have fitted inside the Mosquito bomb bay with bulged doors. Taking off may have been a problem, though.

 

[Vincenzo]

Only 10 B.Mk IV Mosquitoes were built.

you miss series I