Douglas DC-7
Being developed in a time when jet transports were on the brink of entering service the DC-7 was the last of the large piston passenger aircraft. It is a further improvement of the DC-6, so they are very similar. They both have four radial piston engines in the wing leading edges, in the case of the DC-7 with four blade propellers. On top of the nacelles are long oil cooler ducts like on the DC-4. The inner nacelles house the two wheel main gears when they are retracted. The single wheel nose gear retracts forward in the nose. The nose gear bay has a round shape at the front and rear, and hence the nose gear doors have quarter circle curves. The nose is similar to that of the DC-6, as are the rectangular cabin windows and unswept vertical stabiliser with rounded corners, with a curved transition from the leading edge to the dorsal fin.
Different versions
How to recognise the different versions of the Douglas DC-7 will be added later.
Confusion possible with
Douglas DC-6
The Douglas DC-7 looks very similar to the DC-6, regarding general appearance, the cabin windows and tail. However, the engine nacelles of the DC-6 have short oil cooler and the engines power three blade props though and these props not always have large spinners.
Douglas DC-4
The DC-4 is also similar looking, but is significantly smaller than the DC-7. More importantly, the DC-4 has nearly round cabin windows. Also the vertical stabiliser is less tall. Finally, the oil cooler ducts on top of the nacelles are even longer.
Handley Page Hermes
The Hermes can be considered the British counterpart of the DC-6 (and DC-4). The Hermes thus has the same basic appearance as the DC-7, including the two wheel main gears, and rounded rectangular vertical stabiliser. It has rounded square cabin windows though, seven cockpit windows and a rearward retracting nose gear. (photo: RuthAS/WikiMedia)
