The DC3 and C47 range payload issue is complicated by the fact that as engine power grew so does Maxium Takeoff weight: this means more cargo can be lifted without sacrificing fuel.
In additon C47B carried more than the 3046Litres and some variants had an extended wing span. Moreover the C-47 had access to 100/130 octane which increased takeoff power
enormously and therefore payload. The fuel issue (B4/87 octane for the Ju 52 and 100/130 octane for the C-47 explains some of the differences in performance)
My understanding is that range calculations are given at full internal normal fuel load with maximum cargo permissable at that MTOW at cruise speed.
Greater range is possible at reduced load or reduced speed. Reduced speed gets you nowhere in a head wind and irritates passengers as well as wasting aircraft time.
In the C-47's case an overload was possible: this I suspect required 100/130 fuel, a long sealed runway, no obstacles at the end of the runway and probably accepted increased risk of a crash landing if there was an engine failure immeidatly after takeoff. The Ju 52/3m range figures are clearly given at Max Fuel with Max Payload at that Max Takeoff Weight
at maximum cruise. The Ju 52/3mge3 could econ cruise at 117L/100km which would give a range of 2400km at a mind numbing slow speed with little cargo.
Roughly it looks like the basic 1940 DC3 with 20% more fuel than the Ju 52/3m (circa 3000L instead of 2500L) carried the same cargo as the Ju 52/3mge3 some 66% further ie 1000 miles instead of 600 miles.
Assuming a 15% reserve one could argue that a DC3 could supply 2.5 tons of cargo to a base 425 miles away while the Ju 52/3m only 260 miles. This is a huge difference as it
gets the takeoff point well away from enemy fighter attack. The C-47B and better fuel improved these figures. The Ju 52 proably had better short field performance.
Vanir, Ju 52 continued to opperate in New Guinea till 1970. In some situations over short ranges with rough landing fields rugged simplicity, bush mechnic level may be the key factor.
Its worth looking at the Ju 252 parameters:
Crew: 3-4
Length: 25.11 m (82 ft 4¼ in)
Wingspan: 34.10 m (111 ft 10⅛ in)
Height: 5.75 m (18 ft 10⅓ in)
Wing area: 122.6 m² (1,320 ft²)
Empty weight: 13,127 kg (28,880 lb)
Loaded weight: 22,257 kg (49,560)
Max takeoff weight: 24,050 kg (52,911 lb) (overload)
Powerplant: 3 × Junkers Jumo 211F liquid-cooled inverted V12 engines, 1,007 kW (1,350 hp) each
Performance
Maximum speed: 438 km/h (237 knots, 272 mph) at 5,800 m (19,030 ft)
Cruise speed: 335 km/h (181 knots, 208 mph) (econ cruise)
Range: 3,981 km (2,150 nmi, 2,473 mi) with maximum payload, 6,600 km (3,565 nmi, 4,100 mi) with 2,000 kg (4,400 lb ) payload
Service ceiling: 6,300 m (20,670 ft)
Rate of climb: 12.5 m/s (748 ft/min)
http://www.pilotfriend.com/photo_al... Ju 252.htmcraftwwii.com/blog/archive-201108/
Maximum speed was 272 mph (438 km/h) with a maximum cruising speed of 242 mph (390 km/h). The service ceiling was 20,670 ft (6300 m). Range of 2,473 miles (3980 km) with maximum payload. With only 4,410 lbs (2000 kg) of payload range increased to 4,100 miles (6600 km). Empty the aircraft weighed 28,880 lbs (13100 kg), with a normal loadout it weighed 49,560 lbs (22480 kg) and with maximum overload it weighed 52,910 lbs (24000 kg). It had a span of 111 ft 10 in (34.09 m); length 82 ft 4 in (25.10 m); height 18 ft 10 1/4 in (5.75 m) and a wing area of 1,320 sq ft (122.3 sq m).
My reading of this is that at normal (non overload) the aircraft confifuration was
1 Empty weight 13100kg
2 MTOW (normal) 22480kg
3 Cargo 2000kg
4 Therefore assuming MTOW the fuel capacity might be be 22480kg-2000kg-13100kg = 7380kg = about 10000L
Thus carrying 2000kg cargo , 6600km, 7380kg fuel leads to:
1000kg being carried 1000km for 560kg fuel.
As good as the DC3 but over twice the range.
Assuming that when opperating at 2400 miles instead of 4100 miles the fuel load is reduced pro rata to 59%and 10% added; leaving only 5000kg fuel and 2500kg crago added to make up the weight we have
4500kg, 4000km, for 5000kg fuel
1000kg, 1000km, for 312kg fuel.
Much better than the DC3. This is probably produced by a more modern high aspect ratio wing and the good fuel efficiency of the Jumo 213F.
The Ju 252 design was halted to militarise it for a rear loading ramp (it was alwasy duel Lufthansa/Luftwaffe) and then paused to concentrate on more important armaments work.
The delay in producing the Ju 252 may just have cost the Germans a loss at Stalingrad and hastened the Afrika corps demise in Nth Africa. Not only could the Ju 252 have supplied cargo great distances it could do so efficiently (half the fuel of the Ju 52) and it could avoid vulnerable and congested staging fields and the double handling of transhipping from forward train depots to forward airfields.
If you think about it it was a false economy: the Ju 252 could have carried over 2.5 times cargo 4 times as far as the Ju 52 and done so with half the fuel burn per unit of cargo.
In extreme situations it could fly the same weight of cargo 6.5 times the distance for 70% the fuel burn per km.
I would add that burned out engines of Ju 52 at Stalingrad from lack of maintenance and heavy use meant they were restricted from using max takeoff power and this limited loads to as little as 0.5 tons at times. A pitfull waste of human life when one considers the risk to only deliver a small cargo. Again, if one has an adaquet aricraft does one need to overuse it?