The Hs 129 idea done 'right', and for everyone

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Can the concept of "non-strategic" engine include previous generation / models of "strategic" engines? Given how often the engines were upgraded, I imagine it was common to be left with a bunch of inventory when the "important" aircraft switched over to the latest engine versions. ISTR that at the end of the war the Germans had thousands and thousands of Jumo 211's sitting in crates.
 
Can the concept of "non-strategic" engine include previous generation / models of "strategic" engines?

+1 on that idea.
Germans have had the low power versions of their radials still being installed on some aircraft (mostly the legacy BMW 132s on the Ju 52s) as far as 1944. The Polish war booty Mercury on the spin-off on the Fw 187 would've been also interesting, with Mercury being well behind the curve by 1939.

BTW - Argus V12 engines were very much strategic engines (post-war narrative aside), with Germans planing in 1938 to even make new factories for these engines. And, being the supercharged V12s, quite a fancy and expensive way to make a non-strategic engine by the thousands.
 
ISTR that at the end of the war the Germans had thousands and thousands of Jumo 211's sitting in crates.

Too bad that nobody though of retrofitting them with a 2-stage S/C copied by Merlin ...
 

This can go several ways. For the BMW 132s on the Ju 52s, what are you going to use instead on the Ju 52s? Maybe you can restress the engine mounts/local structure to take a more powerful version, but you still need engines for the Ju 52s (new production of plane) and to keep the old ones flying. But now you have complicated logistics for the Ju 52 units. Not a lot.

You could use 9 cylinder radials on the Hs 129 or clones, but there are several downsides. The 129 is a small airplane with not very good vision to begin with. Replacing the under 1 meter 14 cylinder radials with 1.3-1.38 meter radials is going to really screw up the vision in certain directions. They also make bigger targets. They also needed bigger propellers which means less ground clearance, which can be solved with longer landing gear which.............................
You can raise the cockpit to get some of the vision back but? more armor? less speed? Not that it was going all that fast to begin with.
The Germans got lucky, the Hs 129 with the Argus engines was a flop. They fell into possession of the G-R 14M engines pretty much by fluke. And the French had based a large part of their air force around the G-R 14M so there were a lot of them around and there was a decent production line/supply.

Any non-German air force that wants something like the Hs 129 using a 'non-strategic' engine is probably going to wind up with a bigger airplane.
There was a gap between the 600hp engines and the 1000hp engines (aside from the Mercury) and most of the 1930s that fell in there were no longer in production (BMW 132 aside).
For the US P&W was building a trickle of replacement R-1690 Hornets to support existing airplanes. Same with legacy model Wright R-1820s. But building new engines of old models was done at the cost of not building new versions of the engines (or in P&W case, swapping a few Hornets for R-1830 production?).
P&W wanted to stop R-1535 production well before it did, they knew it wasn't going anywhere. They had replaced the R-1690 with the R-1830 except for replacement engines for existing airframes. They had canceled the R-2180 after about 30 engines to build R-2800s.
You need more than an existing design, you need the production capacity to build the existing designs which is going to fight for production capacity for the newer engines.
Unless you can find the magic warehouse.
A lot of times the German eastern allies (or Polish) Engine factories were building a few dozen engines a month. If your anticipated aircraft production can be satisfied with that then fine.


Aside from the Germans I am not sure that any country had hundreds of engines sitting warehouses unallocated. At least not until late in the war.
 
You could use 9 cylinder radials on the Hs 129 or clones, but there are several downsides.

Just a clarification: I'm not advocating an up-engined Hs 129 for this thread, but a better and more capable aircraft all together. Hence also a bit bigger, talk size of Fw 187, not size of Whirlwind.

Any non-German air force that wants something like the Hs 129 using a 'non-strategic' engine is probably going to wind up with a bigger airplane.

'Certainly', not 'probably'
 
You are making good point/s.

The question becomes how much larger (costly) the planes become vs how much extra capability.

You can certainly make more capable ground attack planes but where is the "sweet spot" between a 300sq ft wing, 5000kg (ish) 1400hp plane and a 375-450 (ish) sq ft, 6000-7500kg, 1700-2400hp airplane. Getting into early Douglas DB-7 Territory here (P&W R-1830 engines) and Bf 110s.
Clip the wing on a 110 and replace the DB engines with BMW 132s?
Are BMW 132s non-strategic?
Was some of the BMW 132 production capacity shifted over to BMW 801 Production?

You can take a Mercury engine and change the supercharger gear and go from 725hp for take-off to 830hp but that changes the FTH from 840hp/14,000ft to 890hp/6000ft which is certainly better for ground attack. But is the extra power going to increase the performance of the bigger plane with the larger diameter radials and the extra weight/larger wing?

What are you looking for from the "better" Hs 129? Is an extra 30kph going to do it? or do you need 50-60kph?
 
Just a clarification: I'm not advocating an up-engined Hs 129 for this thread, but a better and more capable aircraft all together. Hence also a bit bigger, talk size of Fw 187, not size of Whirlwind.



'Certainly', not 'probably'
Certainly not certain! There are many other tradeoffs that can easily be made to get more performance WO new engines, such as using better fuel and suping up the old engines reducing wind area, etc...
 
Surely the first matter is to define in what the HS129 deficient? And to do so in a manner that acknowledges that any change has consequences elsewhere. For example it is easy to say that it needed more power but if that comes at the cost of more weight then the wing loading goes up, centre of gravity changes, it needs longer and better quality landing grounds and one must allow for the extra fuel weight and position unless you accept a shorter endurance or range (which are not synonymous).

Define the task and then look to see what can achieve it afterwards. How many do you need/can build in what timescale and at what cost to other programmes?

A passing thought is the Rolls Royce/Rover/Perkins Meteor tank engine. Whilst it came to be made from new it began as a reuse of condemned aero Merlin engine parts reworked to make a normally aspirated engine to run on low octane Pool Petrol. Were there German engines which could be remade in a similar fashion to use low grade fuel at low altitudes? The late Meteors produced about the same 800+bhp power as the initial aero supercharged Merlins, albeit on better than Pool Petrol and with fuel injection.
 

Sweet spot is already at 300 sq ft wing. Two 'normal' radials = 1700+ HP total at 1st (talk low level Mercuries, or short-stroke 9 cyls of German origin).
Bf 110 is a no-go, IMO. Even with clipped wings.

Are BMW 132s non-strategic?
Was some of the BMW 132 production capacity shifted over to BMW 801 Production?

By the time Do 17 was being phased out, the BMW 132 is well behind the curve. Have the 132 (or Bramo 323) production receive support instead of the Argus V12s. Once France is conquered, the G&R 14N can be considered as an upgrade.


I'm looking for a better payload capacity, that can also include the rear gunner. So both the substantial guns' firepower can be carried + some bombs, etc.
Speed is not that relevant.

There are many other tradeoffs that can easily be made to get more performance WO new engines, such as using better fuel and suping up the old engines reducing wind area, etc...

Please, do elaborate.
 
Sweet spot is already at 300 sq ft wing. Two 'normal' radials = 1700+ HP total at 1st (talk low level Mercuries, or short-stroke 9 cyls of German origin).
Bf 110 is a no-go, IMO. Even with clipped wings.
Problem is the field performance.
By the time Do 17 was being phased out, the BMW 132 is well behind the curve. Have the 132 (or Bramo 323) production receive support instead of the Argus V12s. Once France is conquered, the G&R 14N can be considered as an upgrade.
Well, they built around 28,000 Argus engines according to Wiki, if you want to significantly Argus production you need to come up with something for Arado 96 trainers, the FW 189, and the Sibel 204. Maybe you can come up with a 450-600hp 9 cylinder radial. Save 10-20 % ?
I'm looking for a better payload capacity, that can also include the rear gunner. So both the substantial guns' firepower can be carried + some bombs, etc.
Speed is not that relevant.
Back to #1. Getting better payload out of small crappy airstrips requires not just power. Getting back into small crappy airstrips often requires a bigger wing.
 
Problem is the field performance.
Not worse than when compared with bomb-toting Bf 109s of 1940?


Either 9 or 7 cyl engine of that power.

Back to #1. Getting better payload out of small crappy airstrips requires not just power. Getting back into small crappy airstrips often requires a bigger wing.

Starting out with a lot more power is certainly a way to 'beat' the problems of the small airfields. Getting back with landing flaps was a known 'way around' the small airfields well before ww2 started.
 
Not worse than when compared with bomb-toting Bf 109s of 1940?
The idea is to get something better, If the 109 bombers can't take off you need something that will (Hs 123s, Hs 129s, Fw 189s, etc)

Flaps can only do so much. P-38 had flaps.
P-38F at 13500lbs landed (approach at 100mph) and needed about 2500ft from 50ft on hard surface. On wet slipper surface it need about 3300ft just for the ground run. It needed about 1200ft just get from the 50ft altitude down to the runway.

P-47s had flaps, at 10,500lbs (115mph approach) it need 2000ft from 50ft and 1200ft for the ground run. On wet slippery it needed 3600ft from 50 ft and 2800ft of ground run.
 
By the time Do 17 was being phased out, the BMW 132 is well behind the curve. Have the 132 (or Bramo 323) production receive support instead of the Argus V12s. Once France is conquered, the G&R 14N can be considered as an upgrade.
Tomo, if this enhanced Hs129 project is early enough, perhaps BMW could provide the 139 radial as an engine source?
 
Tomo, if this enhanced Hs129 project is early enough, perhaps BMW could provide the 139 radial as an engine source?
The BMW 139 was with even worse reliability problems than the early 801s, due to the in-built heart failure so to speak.
Even if it was a workable engine, the resulting aircraft designed around the two 139s would've been the size & weight of Bf 110/210.
 

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