facts are, under operational conditions, He111s had nowhere near that range. Want an idea of the types true operational capabilities.....look at its operations in the Stalingrad operation, when it operated generally at a range of 150 miles, carrying around 2/3 its max lift capacity.
"The necessary aircraft and crews for the Stalingrad airlift were assembled on short notice from the advanced flight training schools, using mostly Ju-52 and He-111 aircraft (Boog, 1978: 142). The Ju-52 carried about two and a half tons of cargo, and the He-111 could carry only two tons (or 4500 lbs). Von Richthofen began airlift operations as ordered on 24 November. Approximately 320 Ju-52 and Ju-86 transports located at Tazinskaya and approximately 190 He-111 bombers at Morosovskaya (150 miles distant from Pitomnik) were available to conduct the airlift. Neither transport type could trade much fuel for freight, because the distance from Tazinskaya to Pitomik, the main airfield at Stalingrad, was 140 miles (Whiting, 1978: 114). The primary load delivered to Stalingrad was ammunition, which the Germans desperately needed to withstand the Russian attacks. The Germans had previously agreed to slaughter and eat the horses that had carried their supplies when they first arrived in Stalingrad. But eventually even the horses were gone.
The high point of the airlift occurred when 700 tons was delivered between 19 and 21 December—that is, 700 tons for all three days combined (Whiting, 1978: 114).
The supply airfields at Tazinskaya and Morosovskaya fell into Russian hands on 22 December, increasing the distance the transports had to fly from 140 to 200 miles. Manstein gave up hope of relieving Stalingrad on 23 December (Jukes, 1985: 125). At 200 miles, the he 111 had to further reduce lift capacity, down to about half its combat rating. Pitomik airfield was overrun on 16 January, and the smaller auxiliary airfield at Gumrak was seized on 21 January (Whiting, 1978: 115). The Sixth Army was split into two pockets by the Russian Army, with no hope of relief or resupply. Paulus, in the southern pocket, surrendered on 31 January, but the German troops in the northern pocket held out for two more days. German radio reported the fall of Stalingrad on 3 February".
Source:
From Stalingrad to Khe Sanh: Factors in the Successful Use of Tactical Airlift to Support Isolated Land Battle Areas, Dr. David K. Vaughan, Air Force Institute of Technology, Major James H. Donoho, Air Combat Command