A military aeroplane - a Vickers Wellesley Mk.1 general purpose bomber operated by the Royal Air Force (RAF).
Although its serial number is indistinct in this photograph, it is almost certainly either L2638, L2639 or L2680.
Part of the RAF Long-Range Development Flight that broke the world's long-distance record, with modified aircraft, in 1938.
On 5th November of that year, led by Sqdn Ldr. R. Kellett, the three aircraft took off from Ismailia, Egypt, to fly to Darwin non-stop.
L2639 had to land at Kupang, Timor, to refuel but the other two aircraft continued on and arrived at Darwin at 4am GST on 7th November 1938, having cover 7,350 miles in just over 48 hours.
The record was ratified by the Federation Aeronautique Internationale.
The Wellesleys then departed for an around-Australia tour before returning to Egypt.
(Primary source: Aircraft of the Royal Air Force 1918-1957, by Owen Thetford, Putnam, 1957).,