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with "better" engines, and you aren't going to save much in materials and labor by making 725hp BMW 132s vs 880hp BMW 132s, there were several options they could have used.So not quite a 'German DC-3', but it might be what Junkers can quickly introduce in production after the 1-engined Ju 52. There was ~4200 of Ju 52s produced in Germany, so there is ~4200 of engines & props saved. Yes, the engine-out situation is trickier, if indefinitely better than with 1-engined transports. A move to the 'better' 132s (-F and -N, like what Ju 86 had) will be needed once these are available.
You have got a good very good idea of the trade offs.If the engines stay the same, would the tradeoff between losing 1/3 of your power, and lugging the weight of retraction gear (which might weigh close to the engine we've removed), be compensated by the reduced drag and increased aerodynamic efficiency? Would the complication of retractable gear have a real impact on servicing what was apparently a simple and reliable airframe?
I don't know enough to argue one way or the other, but these are the questions that popped in my head immediately.
You might as well keep the tri-motor around for a while until you get the propeller situation sorted out. A twin with 2 pitch props isn't going to fly much further than a twin with fixed pitch. You need either constant speed and a propeller brake or the fulling feathering propeller. And even then you need a certain power to weight ratio to maintain altitude, depending on the route for commercial traffic. Maintaining 5000ft doesn't work crossing the Alps.
To replace the Ju 52 you need ruggedness, capacity/load (12 passenger plane won't do it) and less fuel burned per ton/mile.
with "better" engines, and you aren't going to save much in materials and labor by making 725hp BMW 132s vs 880hp BMW 132s, there were several options they could have used.
You have got a good very good idea of the trade offs.
More power limited than lift limited.Interestingly enough, the 1-engined Ju 52 carried about 10-15% less of cargo than the 3-engined versions.
Installing the 2 better 132s instead of 3 'worse' ones will remove 400-500 kg per aircraft, and it should also gain a less draggy nose. retractable U/C is not a panacea, just another way of removeing some drag from the Ju 52.
All of this should improve the mileage, too.
I misunderstood you. I was thinking of a new airplane and a twin along the lines of the Ju 86 and He 111 commercial aircraft with 10-12 passenger fuselage wasn't going to do it.Ju 52/3m was supposed to carry 15-17 passengers.
Agreed.More power limited than lift limited.
But taking a Ju 52 and putting larger engines on the wings, smoothing up the nose and having the landing gear retract wasn't really going to do it either. It will help but as has been point out by others it may not be worth the expense and extra maintenance.
The Italian S.73 was considerably faster using similar engines.
Max speed over 200mph?
One source says it was about as fast on two engines as the Ju 52 was on all three?
I don't know if the low speed (landing) was better than the Ju 52.
The Savoia-Marchetti SM.75 showed what could be done with a tri-motor using low powered engines in 1937-38.
You won't get your reduction in engines used directly but since the SM. 75 could carry more payload (or at least more men) further and faster using about the same fuel you might need fewer planes to do the same job.
You never saw a ju52 land or take off i think. Very STOL like. Take that and the manner the germans fought and perhaps you can see some befits to Auntie.The Germans should have thrown the Ju-52 to the dump and build the Italian Savoia-Marchetti S.M. 82 as a twin engined transport, powered by Gnome-Rhone 14N radials of 1,140 HP each or the BMW-Bramo 323 engine of 1,000 hp. The vertical stabilizer and rudder would have had to be enlarged to address engine out maneuvering capability. The resultant airplane could have carried 15,000 lbs of weight for at least 1,500 miles at 186 mph. For comparison, the C-47, with 2 R-1930s of 1,200 hp each, could carry about 10,000 lbs at least 1500 miles at 185 mph. The Ju-52 with its antiquated (even for the time) structure could not have made any better no matter what.
The Germans should have thrown the Ju-52 to the dump and build the Italian Savoia-Marchetti S.M. 82 as a twin engined transport, powered by Gnome-Rhone 14N radials of 1,140 HP each or the BMW-Bramo 323 engine of 1,000 hp. The vertical stabilizer and rudder would have had to be enlarged to address engine out maneuvering capability. The resultant airplane could have carried 15,000 lbs of weight for at least 1,500 miles at 186 mph.
The Ju-52 with its antiquated (even for the time) structure could not have made any better no matter what.
Can fitting retracting landing gear on a Ju 52 make up for about a 10% loss in power (two 1000hp engines=2000hp vs three 725hp engines=2175hp) combined with a better nose cone and perhaps straightening out the nacelles so both engines point in the same direction?
And whatever you have to do to the vertical fin and rudder to maintain control in an engine out situation.
Not sure what a 10% loss in take-off power does to the take-off run?
The Ju 52 cruised between 130-150mph? Not saying that drag isn't important but it's real effects go up much faster than actual speed.
A little factoid, the Ju 52's wing was about 20% larger than the wing on a DC-3.
You may save on engines, it doesn't do much for the saving on fuel.
The Germans should have thrown the Ju-52 to the dump and build the Italian Savoia-Marchetti S.M. 82 as a twin engined transport, powered by Gnome-Rhone 14N radials of 1,140 HP each or the BMW-Bramo 323 engine of 1,000 hp. The vertical stabilizer and rudder would have had to be enlarged to address engine out maneuvering capability. The resultant airplane could have carried 15,000 lbs of weight for at least 1,500 miles at 186 mph. For comparison, the C-47, with 2 R-1930s of 1,200 hp each, could carry about 10,000 lbs at least 1500 miles at 185 mph. The Ju-52 with its antiquated (even for the time) structure could not have made any better no matter what.
The Germans had to know just how far behind the Ju 52 was. The Bombay was about 30mph faster and at these speeds that is 18-20%, a substantial difference.
True but the Bombay and the Harrow show that you could have a bit more speed and a bit more capacity while using the same installed power as the JU 52 without the need to go to 4 engines. The two British planes also had low stalling speed and very good short field performance.Anyone air-minded in Germany knew that Ju 52 was behind the curve once the companies started buying DC-2s. With the 'widebody' DC-3, the writing was at the wall.
Junkers upped the bar with Ju 90, Fw with Fw 200, but those were not proceeded with as series- or mass-produced military transports because of different reasons.
True but the Bombay and the Harrow show that you could have a bit more speed and a bit more capacity while using the same installed power as the JU 52 without the need to go to 4 engines.