The Germans needed a better tactical bomber in 1942 (1 Viewer)

[Shortround6]

Having lived in both countries, I can say pretty categorically that lunch, and quality of life in general, is a lot better in France. Americans love to go on at length about the French getting K/O in WW2 pretty quick, but our own W/L track record is looking less and less impressive over time...

Forget modern times, I have no idea what the guys at Wright field were drinking when they kept insisiting that the I-1410 was the way to go or what the guys at Wright were drinking when they came up with the 42 cylinder Tornado or what the guys were drinking when they OK'd the contracts. The US did make a lot mistakes in WW II.
Like the Fisher XP-75.
Designed by the same guy who designed the P-40. A few liquid lunches with a French refugee?

Not necessarily. You seem to keep assuming i want a Ju 88,

Well, I was going by the small engines and referencing the Bréguet 693.

A lot of the most effective, useful and successful bombers of WW2 - Mosquito, DB-7 / A-20, Martin 187 / Baltimore, Ki-48, Pe-2, were all quite small as bombers go. As were most (not all) of the fighter-bombers.

Some of these were a lot more useful than other. I really like the A-20. What hurt it was that they didn't add fuel to it fast enough. It was short ranged in Pacific for too long and the longer ranged, but slower B-25 was the favorite. Not saying that the A-20 could cover the same area as a B-25 but once they got 325 gallons in upper bomb bay a lot of the range problems went away.
The Japanese Ki-48 was not very good. 4 men instead of 3 with a crappy defensive armament and light bomb load and not quite fast enough.
Use 30 fighters to escort 4-6 A-20s or B-25s and see how well the American bombers or use very few fighters to escort the Ki-48s and see how well they do.

 

[Steamed_Banana]

I'm not sure exactly what kind of payload is desired here. From my understanding of what a tactical bomber is here, the French indeed had no domestic project between the Bloch 175 series (up to 600 kg of bombs, e.g 3x200kg or single 500kg + twin 40kg) and the Amiot 35X/LeO 45X (up to 1350kg of bombs). None of these aircrafts were designed around a heavier gun armament either.

One indeed needs a new plane. This is why the French bought the DB-7 in the first place, which filled a neat niche between the bigger twin-engine bombers and the smaller Blochs.

We are looking for something better than a Ju 88A4 or Do 217, basically

 

[z42]

How do you like the Fw 187 as the basis for a new one?

A plane with a fuselage so narrow they had to relocate part of the instruments to the engine nacelles; how are we going to fit a decent sized internal bomb bay into it?

 

[Steamed_Banana]

Forget modern times, I have no idea what the guys at Wright field were drinking when they kept insisiting that the I-1410 was the way to go or what the guys at Wright were drinking when they came up with the 42 cylinder Tornado or what the guys were drinking when they OK'd the contracts.

That's one of the problems with drinking in the US in some cases, they tend to rush past the 'getting there' part and go right into the final state, maybe a little more than needed....

The US did make a lot mistakes in WW II.

Everybody did

Like the Fisher XP-75.
Designed by the same guy who designed the P-40. A few liquid lunches with a French refugee?

Interesting point! Designing aircraft or weapons, or both at the same time, seems a bit like filmmaking. Nobody working on the project at any level can really be sure if it's good or bad until it gets out in the world, and even then sometimes the true verdict may be a generation or two away.

Well, I was going by the small engines and referencing the Bréguet 693.

Ah, gotcha. Well I am a fan of the 693, though I'd probably call it an attack plane or even a strafer more than a bomber. Might have fit into a niche similar to some of the A-20 strafers, in fact, but that is by no means certain, and we'll never know if it could have been good or even great. The 693 and it's engines were definitely very far over on the side of smol. I guess I was thinking 'middling' vs 'real big', per the specific examples I posted.

Some of these were a lot more useful than other. I really like the A-20. What hurt it was that they didn't add fuel to it fast enough. It was short ranged in Pacific for too long and the longer ranged, but slower B-25 was the favorite. Not saying that the A-20 could cover the same area as a B-25 but once they got 325 gallons in upper bomb bay a lot of the range problems went away.

I agree, though the A-20C / Boston III version was close enough to a sweet spot to be quite useful, and even the early / short ranged ones were useful. The A-20G was better but it came a bit late. A-20 in general is one of those nice systems which seems to be little thought of initially but gradually finds more and more niches an more and more success. B-25 is good too mind you and it is also a bit counter-intuitive in some ways (it seems a bit too heavy, too slow -especially for the later war- and overbuilt, but it proved useful in many parts of the world and for a long time, and like the A-20 fit into many roles. Which brings me to....

The Japanese Ki-48 was not very good. 4 men instead of 3 with a crappy defensive armament and light bomb load and not quite fast enough.
Use 30 fighters to escort 4-6 A-20s or B-25s and see how well the American bombers or use very few fighters to escort the Ki-48s and see how well they do.

... ultimately it comes down to whether they could make it work. And they made the Ki-48 work. The heavy B-25 and the lighter weight / faster types I listed - Mosquito, Ki-48, Baltimore, Pe 2 (we could also say later on, the Tu 2) and many fighter-bomber types did prove to have a useful niche and were made to work. It's super difficult to predict, at the design level, everything that is going to be needed when it's in the field, and after it's been in action for a year or two years etc.. What had to be done was to create something with the right traits to survive and do the job somewhat effectively initially, and be amenable to improvements and upgrades over time. All of the successful types shared these traits to some extent.

 

[Shortround6]

A plane with a fuselage so narrow they had to relocate part of the instruments to the engine nacelles; how are we going to fit a decent sized internal bomb bay into it?

I kind of like the original Fw 187 and I like what it might have been with 1940/41 DB 601s but some of the "developments" seem to need pixie dust.
For Wing area/size it was about same as a P-38.
So take a P-38 and make it a two seater (proper, not the nightfighter hack job) or not (?).
add internal fuel for longer range without drop tanks?
install bomb bay of desired size (???)
Perhaps had dive brakes for dive bombing?

How big did the fuselage get?
How heavy did the plane get?
FW 187 with Jumo 210s was about 11,000lbs, a P-38F was around 15,000lbs clean with 300 US gallons of fuel
Granted you can ditch some of the guns/ammo and you can ditch the turbos but over 13,00lbs with low fuel and no bombs?

 

[Steamed_Banana]

I don't know about P-38 as a bomber, two crew plus a bomb bay sounds like a really big redesign. Maybe there is room in the booms for bombs if you take out the turbo and all the turbo plumbing? I don't know, seems dubious.

But speaking of French planes, what if the Germans developed the LeO 451? That seems like a very promising early war design with a lot of room for growth, and right out the gate it's faster than a Ju 88, long ranged, good altitude performance, has a big theoretical bomb load of 1400 kg (not sure about the bomb bays?) and carries defensive guns (albeit kind of an oversized main one on the dorsal spot), but I'm sure the Germans could improve on that (and also ditch the ventral gondola)

 

[tomo pauk]

A plane with a fuselage so narrow they had to relocate part of the instruments to the engine nacelles; how are we going to fit a decent sized internal bomb bay into it?

Bomb can be hung outside.

I kind of like the original Fw 187 and I like what it might have been with 1940/41 DB 601s but some of the "developments" seem to need pixie dust.
For Wing area/size it was about same as a P-38.
So take a P-38 and make it a two seater (proper, not the nightfighter hack job) or not (?).
add internal fuel for longer range without drop tanks?
install bomb bay of desired size (???)
Perhaps had dive brakes for dive bombing?

As above - I'd suggest not fiddling with an internal bomb bay on the Fw 187.
As-is, it already have had 300+ US gals of fuel That is plenty enough for the tactical duties. There is some free volume in the wings for more fuel; drop tanks are not a bugaboo, need be.

 

[Shortround6]

I agree, though the A-20C / Boston III version was close enough to a sweet spot to be quite useful, and even the early / short ranged ones were useful. A-20 is one of those nice systems which seems to be little thought of initially but gradually finds more and more niches an more and more success. B-25 is good too mind you and it is also a bit counter-intuitive in some ways (it seems a bit too heavy, too slow -especially for the later war- and overbuilt, but it proved useful in many parts of the world and for a long time, and like the A-20 fit into many roles. Which brings me to...

The US switched direction in 1941 with the B-25 and somewhat the B-26.
The early B-25 was good for around 315-322mph? which is not bad but it is around 25mph slower than the A-20 which kind of puts in the not quite fast enough category.
They were also looking for a lot of range, like close to 2000 miles when flying slow at optimum speeds. Which meant co-pilot for 8-10 hour flights, which never happened aside from the raid on Tokyo. First 40 or so B-25s were the really fast ones but they had no turret. A single .30 cal (not .50) firing out of hatch in the roof. Either a limited field of view/fire or gunner and gun are fighting a bad slip stream. There was also a hatch in the floor (.30 cal. gun) and a window in each side, however there were not 4 guns. gunner/s had to move one of the guns to the needed mount. Front gun was also a .30 and the rear gun was finally a .50, except the gunner fired it laying on his stomach in the narrow tail cone. Also little or no armor or fuel tank protection? After looking at the BoB results teh Americans figured that very low 300mph was not going to work and 3-4 .30cal guns and single .50 was not going to work they were willing to swap a little speed for better gun armament. Unfortunately while the upper turret worked the lower, retractable, aimed by periscope, turret did not and since they got rid of the rear/tail gunner they wound up with some large blind spots.
With the 'require' crew of Pilot, co-pilot, radio operator and navigator (gunners are optional?) (long over water flights) they can't shrink the fuselage much and they can't reduce the fuel load much so they are sort of stuck with the size of the plane.

Early B-26s were also in the Mid 320mph range when running light. But they never went into combat that way. Early Specifications are the things of dreams. The 320 + mph was done without bombs and about 400 gallons in tanks and you don't fly very long feeding a pair of R-2800s with only 400 gallons
Going into combat with only 200rpg for the upper turret was never going to happen either. An extra 400 rounds was listed as optional overload.

Perhaps the US swung too far the other way towards guns but with the B-26 they were already using the largest engine and the smallest wing (least drag) they could and they found out they gone too far that way. B-26 lost a lot of speed when they enlarged the wing and the tail for better handling with in a one engine out situation and when they tilted the wing 3 degrees of shorter take-off distance they lost more speed. Keeping the larger/tilted wing and larger tail and getting rid of guns was not going to get most of the speed back.

 

[Shortround6]

I don't know about P-38 as a bomber, two crew plus a bomb bay sounds like a really big redesign. Maybe there is room in the booms for bombs if you take out the turbo and all the turbo plumbing? I don't know, seems dubious.

But speaking of French planes, what if the Germans developed the LeO 451? That seems like a very promising early war design with a lot of room for growth, and right out the gate it's faster than a Ju 88, long ranged, good altitude performance, has a big theoretical bomb load of 1400 kg (not sure about the bomb bays?) and carries defensive guns (albeit kind of an oversized main one on the dorsal spot), but I'm sure the Germans could improve on that (and also ditch the ventral gondola)

depends, as I have said, what you what a tactical bomber to do.
A leO 451 might be excellent for bombing railroads, bridges, supply dumps and even airfields in the rear areas.
But with a wing about 14% bigger than a B-25 wing (unless you clip it) and fuselage about 1 meter longer maybe you don't want to use it for trying to bomb front line troops very often?
Unless from around 10,000 ft or higher? Bombload for short range missions may be bigger than you think. The LeO 451 could trade a lot of fuel for bombs.
The ventral gondola was actually the retractable ventral gun and yes there were better ways to protect the belly of the airplane than lowering a man with a single rcmg into slipstream even if the man was protected from the slipstream.

 

[Steamed_Banana]

The US switched direction in 1941 with the B-25 and somewhat the B-26.
The early B-25 was good for around 315-322mph? which is not bad but it is around 25mph slower than the A-20 which kind of puts in the not quite fast enough category.
They were also looking for a lot of range, like close to 2000 miles when flying slow at optimum speeds. Which meant co-pilot for 8-10 hour flights, which never happened aside from the raid on Tokyo. First 40 or so B-25s were the really fast ones but they had no turret. A single .30 cal (not .50) firing out of hatch in the roof. Either a limited field of view/fire or gunner and gun are fighting a bad slip stream. There was also a hatch in the floor (.30 cal. gun) and a window in each side, however there were not 4 guns. gunner/s had to move one of the guns to the needed mount. Front gun was also a .30 and the rear gun was finally a .50, except the gunner fired it laying on his stomach in the narrow tail cone. Also little or no armor or fuel tank protection? After looking at the BoB results teh Americans figured that very low 300mph was not going to work and 3-4 .30cal guns and single .50 was not going to work they were willing to swap a little speed for better gun armament. Unfortunately while the upper turret worked the lower, retractable, aimed by periscope, turret did not and since they got rid of the rear/tail gunner they wound up with some large blind spots.
With the 'require' crew of Pilot, co-pilot, radio operator and navigator (gunners are optional?) (long over water flights) they can't shrink the fuselage much and they can't reduce the fuel load much so they are sort of stuck with the size of the plane.

I don't think the issue was just weight, for either B-25 or B-26, it was the fuselage size, and size overall, as well as the turrets and . The deployed B-25s as far as I know were well under 300 mph top speed, more like 275 mph, with a cruising speed around 230 mph.

The A-20s did suffer for the lack of a co-pilot, mind you. One wonders if they could have done a staggered arrangement like on the Mosquito. The contrast between the A-20 and also the slightly smaller Martin 187 Baltimore vs the B-26 Marauder from the same company, to me kind of looks like a difference in specs for a European client, i.e. France which was the first interested party in the DB-7, and then UK, vs the USAAC / USAAF. Different philosophies, different approaches. Both did ultimately work out.

Early B-26s were also in the Mid 320mph range when running light. But they never went into combat that way. Early Specifications are the things of dreams. The 320 + mph was done without bombs and about 400 gallons in tanks and you don't fly very long feeding a pair of R-2800s with only 400 gallons
Going into combat with only 200rpg for the upper turret was never going to happen either. An extra 400 rounds was listed as optional overload.

Perhaps the US swung too far the other way towards guns but with the B-26 they were already using the largest engine and the smallest wing (least drag) they could and they found out they gone too far that way. B-26 lost a lot of speed when they enlarged the wing and the tail for better handling with in a one engine out situation and when they tilted the wing 3 degrees of shorter take-off distance they lost more speed. Keeping the larger/tilted wing and larger tail and getting rid of guns was not going to get most of the speed back.

Again I think the sheer ... Girth of the B-26 fuselage was a big factor with the ultimate speed, though you are right the wing size increase was part of it too. It was a bit faster than the B-25 (usually shown around 280-285 mph) but cruise speed, oddly enough, was lower at 216 mph. Maybe it just took so much effort to push that beefy fuselage around. It did have good range though.

One big issue with the Baltimore was that takeoffs were dangerous, requiring near perfect throttle control. The British just trained their pilots and sucked up the extra operational losses. The US found it a deal breaker. British also didn't seem to have a lot of problems with their early Marauders .. were those the short winged ones? And they managed to get torpedoes under them which made it vastly more useful as an anti-shipping weapon.

It seems like another missed opportunity that the US didn't do a Reverse Lend-Lease for bunch of British torpedoes and lash them beneath their Marauders, and maybe A-20s too. The Soviets managed to get their torpedoes under the A-20. It was one of their most important bombers.

 

[Steamed_Banana]

depends, as I have said, what you what a tactical bomber to do.
A leO 451 might be excellent for bombing railroads, bridges, supply dumps and even airfields in the rear areas.
But with a wing about 14% bigger than a B-25 wing (unless you clip it) and fuselage about 1 meter longer maybe you don't want to use it for trying to bomb front line troops very often?
Unless from around 10,000 ft or higher? Bombload for short range missions may be bigger than you think. The LeO 451 could trade a lot of fuel for bombs.

Well, if you combined that with long range FW 190G for both escort and fighter-bomber duties, you would have had a major asset that the Germans sorely lacked in the Western Desert from mid 1942 through 1943, and one (had it been available in numbers etc.) that they really could have benefited from I think.

If LeO 451 makes 300 mph with a 1,000 hp Gnome Rhone 14N, how fast is it with a pair of Jumo 211 with 1,400 hp?

The ventral gondola was actually the retractable ventral gun and yes there were better ways to protect the belly of the airplane than lowering a man with a single rcmg into slipstream even if the man was protected from the slipstream.

Ventral gondolas seem to be one of those 1930s Buck Rogers things that never really worked out in practice. The quicker they were rid of them the better.

(Mind you, not disparaging Buck Rogers space ships by any stretch, it's just unfortunate that we never developed the necessary gravity beams to make them work properly)

 

[don4331]

I kind of like the original Fw 187 and I like what it might have been with 1940/41 DB 601s but some of the "developments" seem to need pixie dust.

Most of the "developments" for the Fw.187 needed the whole shaker of pixie dust...

Fw.187 with Jumo 210s has empty weight of ~8,000lb.; DB601s weigh ~350lbs each, you need radiators 1/3 bigger than for Jumo, etc.​

(We will note Fw.187 gained ~2k lb. going from V1 to V4 to add a 200lb* navigator and 2 - MG/FF cannon @ ~60lb each)​

The biggest thing the Fw.187 did was demonstrate Dr. Tank could indeed design a state of the art aircraft after the fiascos of the Fw.57 and Fw.159. And that got him the contract for the Fw.190 (2nd fighter using a non-strategic engine aka BMW801). Reducing Bf.110 production by the number of Fw.187 would be boon for RAF night bombers.

Messerschmitt needed to have a unified design team on the Me.210, to get the weight and balance correct out of the box.

Having the tail designed by an independent team (and come in heavy) made the plane unstable.​

​

*200lbs includes the navigator, his cold weather suit, his parachute and his extra oxygen bottle.

 

[Steamed_Banana]

I thought the problem with Me 210 was the wing...

 

[Shortround6]

I thought the problem with Me 210 was the wing...

Most or all of the handling problems went away when they lengthened the fuselage by about 1 meter.
There were 3 planes in the series. The original 210s, The Hungarian 210s (most or all with longer fuselages) and the 410 with different wings, DB 603 engines and the long fuselage.
The 410 may have used the different wings to compensate for the Db 603 engines.

 

[yulzari]

Tongue in cheek, but if only one could dive bomb at night then the JU87 can stagger into the air with a 1,000kg bomb for precision tactical targets. IOTL it was actually used over Britain in single aeroplane sorties but not in the full 90 degrees dive. Perhaps with a low-high-low profile?

 

[tomo pauk]

Most of the "developments" for the Fw.187 needed the whole shaker of pixie dust...
Fw.187 with Jumo 210s has empty weight of ~8,000lb.; DB601s weigh ~350lbs each, you need radiators 1/3 bigger than for Jumo, etc.(We will note Fw.187 gained ~2k lb. going from V1 to V4 to add a 200lb* navigator and 2 - MG/FF cannon @ ~60lb each)

Trick was that there was actually a Fw 187 with DB 601 made in metal.
There was no pixie dust when Bf 109 went from D to E and then to the F version, no pixie dust to arrive at Spitfire XIV, no pixie dust when Mustang grew from the Mk.I to Mk.III. People generally have no objections when the P-51F/G/H still carries the P-51 Mustang name, despite having perhaps a ~95% parts difference with the Mustang I. Pixie dust when MC.200 grew to MC.205, and Re.2000 to 2005. LaGG-3 into La-7 anyone? P-47B into P-47N?

Reducing Bf.110 production by the number of Fw.187 would be boon for RAF night bombers.

No boon there.
A Daimlerized Fw 187 can take the role of a fast bomber from the slow Ju 88, meaning that more Ju 88s can be night fighters.
The Fw 187 can also be better as a night intruder than the slower types, to harass the bomber bases.

 

[Howard Gibson]

The other bomber design issue which does seem to be tricky, and maybe harder than I tend to assume, is the size of internal bomb bays. If you have a large internal bomb bay with the capacity for bigger bombs, say at least four 500 lb / 227 kg sized bombs, the bomber is going to be much faster on ingress and could maintain a high cruising speed, and will also have much better range. This was one of the advantages of the Mosquito Mk IV.

An interesting problem with WWII bombers was the position of the wings. The bombs must be mounted somewhere close to the centre of lift, so inevitably, they wind up at the same station as the wings. If you have a low-wing monoplane like a B17 or a Ju88, the wing main spar(s) pass through the bomb bay, limiting the size of your bombs. The de Havilland Mosquitos and Avro Lancasters were mid-wing, leaving lots of open space. The B24 Liberators were high wing, potentially leaving even more space.

 

[z42]

An interesting problem with WWII bombers was the position of the wings. The bombs must be mounted somewhere close to the centre of lift, so inevitably, they wind up at the same station as the wings. If you have a low-wing monoplane like a B17 or a Ju88, the wing main spar(s) pass through the bomb bay, limiting the size of your bombs. The de Havilland Mosquitos and Avro Lancasters were mid-wing, leaving lots of open space. The B24 Liberators were high wing, potentially leaving even more space.

A recent example of this conundrum being the P-8, a maritime patrol version of the B-737. Wing box and wheel wells being in the way, they decided to put the bomb bay behind the wing. Granted, a B-737 is a huge bird compared to any WWII bomber, and a few sono buoys and torpedoes(?) don't affect Cg that much I presume. Still looks somewhat jarring.

 

[Dimlee]

Since 1943 is mentioned in the first post...
This is the year of the first flights of the Do 335 and Ar 234. Aren't they the best tactical LW bombers for what-if 1944-1945?
I'm not sure whether the Do 335's development could be sped up, or whether such problems as overheating, vibration, and pilot ejection safety could be resolved at all.
However, Ar 234's history could be different if:
- Arado concentrates first and mostly on this model, dropping the "dead ends", such as Ar 240/440.
- Conventional landing gear from the outset, probably, would save half a year at least.
- RLM already in 1941 foresaw the deficit of nickel and chromium (required for Jumo 004A blades), prioritised Jumo 004B, directed the required resources accordingly, and Junkers started to work on the hollow blades. Another year saved?
- Decision makers such as Milch were less sceptical about jet technology.
Even in real life, Ar 234, arguably, was the best tactical bomber of its period. What if production/deployment/training began 1.5 years earlier and en masse?

 

[Howard Gibson]

A recent example of this conundrum being the P-8, a maritime patrol version of the B-737. Wing box and wheel wells being in the way, they decided to put the bomb bay behind the wing. Granted, a B-737 is a huge bird compared to any WWII bomber, and a few sono buoys and torpedoes(?) don't affect Cg that much I presume. Still looks somewhat jarring.

View attachment 871913

A de Havilland Mosquito BXVI had an empty weight of 14,600lb and a maximum weight of 23,000lb. Presumably, this could include a 4,000lb "cookie". A Boeing 737 has an empty weight of 65,300lb. What was the bomb load?