Henschel 129 built with more powerful engine

[stg 44]

http://en.wikipedia.org/wiki/Henschel_Hs_129
http://en.wikipedia.org/wiki/BMW_132

What if the Hs129 was designed around the BMW 132 radial air cooled engine of 950hp? Historically this aircraft was initially built with the the Argus 410 engine which only put out 450hp, which left the aircraft horribly underpowered. It was undeployable when first delivered in 1941 and required the more powerful Gnome-Rhone engines that put out about 700hp, but this delayed the entry of this CAS aircraft until 1942 and it was still underpowered.
It proved to be a necessary and successful aircraft in CAS, but was always viewed as the 'red headed stepchild' of the Luftwaffe and not really a focus of resources, which prevented it from making a greater impact on the Eastern Front.

So what if the designers were given access to the necessary powered engines? The aircraft would have to be bigger to accommodate the larger engines, which is actually a good thing, as a major complaint about the Hs129 was that it was too cramped. The larger aircraft would be heavier, but with nearly 2000hp instead of the 1400hp of OTL the Hs129 could handle the extra weight (about 1500kg at most). This would mean that it would be designed from the beginning with more powerful engines, so wouldn't need to be delayed to be redesigned for new engines. It would also be able to take the upgrades of weapons packages much better than OTL version.

Where are these extra engines to come from? Well the BMW 132 was used for the Ju52 transport aircraft, which was pretty important to the war effort so the engines will have to come from that pool. Germany in 1939 and 1940 had serious problems with organizing her industry and could have produced extra engines, say in the VW factory built just before the war started and was never utilized to full capacity during the war and between 1939-1942 the factory was using less than 50% of productive capacity. So the engines could have been produced there, as they were already making air cooled auto engines for the Kuebelwagen. Also the BMW 132 was one of the cheapest engines to make during the war for Germany and was produced for a number of years prior to the war, meaning its production wasn't something that would require a major learning curve to open a new live for its production. What was lacking was the will to do so (and the bureaucratic organization/unity of purpose) , not the resources.

So what impact would this CAS aircraft have? The early models had the 20mm cannons, which had access to the tungsten core ammunition stockpiled pre-war in the millions, so would be more effective than the caliber would indicate. Plus in 1941 the Luftwaffe had air superiority over the Eastern Front, not that that was the major problem of the Hs 129, which historically lost many more, by a factor of 3 or 4 to 1, to ground fire from 3cm+ AA guns than to fighter planes.

The testing units received their first models OTL in November of 1940, so that would mean that the mass production of these aircraft would start until 1941 and the time it would take to create units would mean that they would likely miss the first phase of combat in Barbarossa, though the testing units would get to fly in combat, as they did with the other models. So the first squadrons would appear some time in August so would be around for the Kiev pocket and other battles. Obviously 1941 isn't going to be very different.

From 1942 on things start to get interesting, as production increases and more models appear at the front. Also the need for better cannons is revealed earlier, so they potentially would be getting the 30mm cannons earlier than historical. Historically the small numbers of Hs129s flew over 3000 sortees during 1942, so they had a large demand and more of them would help reduce German losses during their advance and increase Soviet losses.

During 1943 would be the large effect. By now the 30mm would be in widespread use, as would the Hs129. It would have all of its issues sorted out and be an effective tank killer.

What effects would the more widespread Hs129 have from 1942 onward in the big tank battles that were occurring? Would the effect of a solid tank buster help the Germans on the Eastern Front enough to influence the outcomes of some battles through the added attrition of Soviet tanks/vehicles?

[phylo_roadking]

Hi....and once again we run into all the same issues as the RLM had with all its aircraft - competing priorities

Where are these extra engines to come from? Well the BMW 132 was used for the Ju52 transport aircraft, which was pretty important to the war effort so the engines will have to come from that pool.

And a few more besides! The Arado Ar 196, Arado Ar 197, Blohm & Voss Ha 140, Blohm & Voss BV 141, Heinkel He 114, Heinkel He 115, Henschel Hs 123, Junkers Ju 160, Junkers Ju 52, Junkers Ju 86 and Junkers W34!

Unfortunately I don't have production numbers for several of those...but what I do, it looks like anything up to ~2,000 BMW132s of various variants were built and fitted to other Luftwaffe aircraft than the Ju52...and of course probably many more engines'-worth of spares While Ju52 usage alone accounted for at least 14,500...

Also the BMW 132 was one of the cheapest engines to make during the war for Germany and was produced for a number of years prior to the war, meaning its production wasn't something that would require a major learning curve to open a new live for its production. What was lacking was the will to do so (and the bureaucratic organization/unity of purpose) , not the resources.

It also happend to require the tooling for a full production line (or several), and the skilled manpower to built them. In the meantime, while a cadre of experienced personnel is transferred to VW to train the new production line staff...production at BMW of the 132 goes down

And of course...Germany is meanwhile experiencing all her historical problems with skilled manpower

None of these decisions were ever easy for the RLM, as your own source shows...

One last requirement, a non-technical one, ended up dooming the designs: the RLM demanded that the aircraft be powered by "unimportant" engines of low horsepower that were not being used in other designs, so the plane's production would not interfere with that of other types deemed more essential to the war effort.

Hard to magic that particular requirement...or more importantly the reasons for it...out of the way!

[stg 44]

Of course there is always the Milch option: deskilling and specialized tooling in lieu of general purpose machinery. Seeing as the VW plant was tooled up anyway with general purpose machinery during the war, why not request machinery that would eliminate the need for skilled machinists. Later in the war the aviation industry was returning general purpose machinery that was being produced to get specialized machines for mass production equipment, so why not earlier? Again I know its the issue of bureaucracy that was the problem, but assuming some sort of POD, like Wimmer not pissing Göring off and getting replaced by Udet, materially it shouldn't be a big stretch. Ultimately it came down to the will to create the necessary equipment, rather than a material lack, as you demonstrate above; we could eliminate those useless aircraft mentioned above and have the necessary engines and resources to build the HS129.

[kfbr392]

What if the Hs129 was designed around the BMW 132 radial air cooled engine of 950hp?

once again, I pondered and contemplated a what if for many months, finally did a forum search on it - and user “stg 44” already went there!
great post, my friend!

First of, could the BMW 132 even have been physicaly mounted in the Hs 129? BMW 132 engine diameter is 1380mm and propeller diameter (in Hs 123A-1) 3100mm vs. 964mm and 2600mm for the GR 14M in OTL Hs 129B. Propeller diameter increase may be a no-go.

[stg 44]

What if the Hs129 was designed around the BMW 132 radial air cooled engine of 950hp?

once again, I pondered and contemplated a what if for many months, finally did a forum search on it - and user “stg 44” already went there!
great post, my friend!

First of, could the BMW 132 even have been physicaly mounted in the Hs 129? BMW 132 engine diameter is 1380mm and propeller diameter (in Hs 123A-1) 3100mm vs. 964mm and 2600mm for the GR 14M in OTL Hs 129B. Propeller diameter increase may be a no-go.

I did say that 'designed around' which means the Hs129 would be different in this 'what if', as it would be designed initially to mount the BMW 132.

[kfbr392]

true.

Well, such a Hs 129 would have been an excellent little aircraft, even better than the fine OTL Hs 129B.
And production could have been much greater since the French engine factory would not have been the bottleneck it historically was.

I estimate the switch from As 410 to GR 14 engines in OTL caused a delay of ca. 9 months.
So all other things being equal (meaning there are Hs 129A-0 with terrible cockpits which are rejected), you would have had Hs 129B-1 delivered from Apr 1941 (OTL: Jan 1942), and sorties flown from Aug 1941 (OTL: May 1942). MK 101 would first be used in combat in small numbers in Sep 1941 (OTL: June 1942).


Rommel could have had a Gruppe (~53 a/c) from late 1941.

A full Geschwader (~160 a/c) could have been thrown against the Soviet encirclement attempt of 6. Armee at Stalingrad in Nov 1942. It could have severly reduced the tank strength of the Soviets there.

[Ifor]

Due to the latest research i was under the impression that the amount of armour lost to air support was a lot less than originally thought(Western front). Were the figures more favourable in the Eastern Front?

[thaddeus_c]

still think it would have been better to continue with HS-123 (using the BMW 132 engine) and use the French engines to upgrade the FW-189 and convert more Gotha gliders to powered flight.

[stg 44]

Due to the latest research i was under the impression that the amount of armour lost to air support was a lot less than originally thought(Western front). Were the figures more favourable in the Eastern Front?

Depends on the situation. In Normandy the attacks were made by fighter-bombers who were moving too fast and using too inaccurate of weapons (rockets largely) to really pull off knock outs of armored targets. In the East there was certainly overclaiming, but the slower moving airplanes with cannons had a much better hit and knockout ratio. Carpet bombing with HEAT submunitions or incendiaries probably wasn't as effective as claimed and during Kursk overclaiming was proven to be a problem for both sides, but dive bombing was much more effective and during fighting like around 2nd Kharkov bombers did smash large road marching formations of vehicles confirmed by later ground overruning of the wrecks:
https://en.wikipedia.org/wiki/Second_Ba ... terattacks

The Luftwaffe had pretty huge success in Crimea (both Kerch and Sevastopol) plus during Case Blue and later the battle for Stalingrad. Having a dedicated platform for low, slow close air support while the Luftwaffe had air superiority would help a lot.

[T. A. Gardner]

The Argus powered Hs 129 was really badly underpowered and almost a death trap to fly, particularly once loaded with munitions. The switch to the G-R 14M was a needed, if something of a desperation move.
If anything, the Hs 129 needed to be a larger plane than it was and it could have been powered by either a Jumo engine or maybe an Hispano-Suiza 12Y. This would have provided the necessary power to make it capable of carrying a decent bombload, along with a good gun armament and some armor. Shoving one of those tank buster cannon on it wouldn't have doomed it to being a barely airworthy plane. H-S 12Y was manufactured under license in Czechoslovakia, as well as being available in France. That would have allowed production of the engine along with not impacting German production. Maybe the Germans could have gathered up the tooling in France and expanded Czech production.

That would put a 1,000 hp engine on the Hs 129 which should be enough to make it airworthy with a load. If the H-S 12Y is chosen right from the start, it eliminates the issues with switching engines the original plane design had.

[kfbr392]

still think it would have been better to continue with HS-123 (using the BMW 132 engine) and use the French engines to upgrade the FW-189 and convert more Gotha gliders to powered flight.

there was a Fw 189E: Prototype only, powered by two 700 PS (690 hp, 515 kW) Gnome-Rhone 14M radial engines.
Sounds like a good idea to me.

The Gotha Go 244 was useless as it was terribly underpowered. So much so that many were rebuilt to Go 242s gliders in 1943.

I am a strong proponent of the Hs 123 as I have argued elsewhere in this forum.
But the Hs 129 had a number of definite advantages over the Hs 123:
-stronger machine gun armament (i am talking about the 8 to 20mm caliber range) and more ammo; all guns fuselage mounted
-30mm automatic cannon along fuselage centerline
-armored cockpit („steel bathtub“)
-better visibility (especially forward and downwards) for pilot
-twin engines in order to limp home on one engine if necessary

[Sheldrake]

http://en.wikipedia.org/wiki/Henschel_Hs_129
http://en.wikipedia.org/wiki/BMW_132
What effects would the more widespread Hs129 have from 1942 onward in the big tank battles that were occurring? Would the effect of a solid tank buster help the Germans on the Eastern Front enough to influence the outcomes of some battles through the added attrition of Soviet tanks/vehicles?

Virtually none.The physical effectiveness of aircraft in WW2 as tank killers has been exaggerated since the war, with service and industrial interests promoting the merits of aircraft. Closing to attack tanks with cannon was wasteful in aircraft and fatal for lost airmen.

The systematic studies in the west theatre reveal over counting by a factor of 2-3. I have not seen any studies that back the high claims made by the German or Red air force. It is quite likely that more damage was inflicted on the air force if actual losses were compared, factoring in the relative costs of manufacture and training. The British moved to Rocket Projectiles because they could be launched from out of range of Light AA,even thought they were much less effective against tanks than 40mm or 57mm cannon.

However, the morale effect of air to ground weapons cannot be underestimated.RP were good for that.

[thaddeus_c]

still think it would have been better to continue with HS-123 (using the BMW 132 engine) and use the French engines to upgrade the FW-189 and convert more Gotha gliders to powered flight.

there was a Fw 189E: Prototype only, powered by two 700 PS (690 hp, 515 kW) Gnome-Rhone 14M radial engines.
Sounds like a good idea to me.

The Gotha Go 244 was useless as it was terribly underpowered. So much so that many were rebuilt to Go 242s gliders in 1943.

I am a strong proponent of the Hs 123 as I have argued elsewhere in this forum.
But the Hs 129 had a number of definite advantages over the Hs 123:

the FW-189 that they put in competition with HS-129 was armored, almost unrecognizable as FW-189 and they found unsatisfactory? however they schemed a "lightly" armored one with the French radial engines or the larger Argus engine, THAT seems to be a good balance? faster, still a recon aircraft, but able to attack targets opportunistically?

the GO-244, as is, could function as transport behind their lines and a STOL aircraft was useful. however was mainly focused on design form with the ease of loading and unloading and use of wood for construction as was later used on JU-352. my understanding they never added self-sealing fuel tanks? so that would be needed along with increased fuel capacity.

(just IMO) it would have been better to remanufacture HE-111s as Zwillings to tow Gotha aircraft (powered) that could then make return flight under their own power that construct the huge (target) ME-323?

HS-129 seems like odd case, better with the BMW radials from start of course. they could just never construct as many of them as they could have "spammed out" the HS-123 by onset of Barbarossa?