Avro Lancaster Long Range Saddle Tanks

As it was expected that the Avro Lancaster was going to be the main bomber of the Tiger Air Force, the Commonwealth air unit destined to take part in the Operation Downfall, the Allied invasion of Japan in late 1945. The Lancasters destined to this unit were painted in white with black undersides and outfitted with additional radio units and navigational aids, in order to adapt them to the Pacific Theatre.
As the average ranges in the Pacific were much longer than in Europe, one Lancaster Mk.I was modified with the addition of external long range saddle fuel tanks on the upper central fuselage and was tested in Australia and India during November 1944, but as they proved to be really vulnerable when attacked, they were discontinued.

Sources:
1. https://en.wikipedia.org/wiki/Avro_Lancaster
2. Signal Squadron - Aircraft In action 52 - Lancaster in Action