B707 being unloaded (Picture Spanish Air Force)
The Boeing B707 is one of the most known and successful jet aircraft ever built, first testing aircraft Boeing 367-80 made its maiden flight already in 1954.
Boeing itself named the aircraft B717 – and the derived civilian version became B707. But before several different civilian versions were built including one for commercial air transport (slightly larger), Boeing developed a military transport- as well as a tanker version for the U.S. Air Force: C-135 and KC-135.
When these aircraft entered service in 1958, they revolutionized aviation - owing to their speed, range, high performance and cost effectiveness. The first military variant flying was a KC-135A “Stratotanker”. It was originally built to only supply the strategic B-52 fleet of the U.S. Air Force.
Numerous Air Forces acquired the Boeing B707 either as new aircraft or as used aircraft reconfigured for the Air Transport, Air-to-Air Refuelling (AAR) or Electronic Warfare roles. The most notable military versions are the E-3A Sentry (AWACS – Airborne Early Warning and Control System) with a large rotodome on the fuselage, the E-6 Mercury and the E-8 Joint STARS. Since the beginning of military and civilian service more than 1.000 aircraft have been built while most of the civilian aircraft still in existence have been modified into cargo aircraft.
The Spanish Air Force acquired its B707-300b in 1987, because it had become necessary to replace the DC-8 aircraft of Air Force Squadron 408 and at the same time to ensure AAR of the F-18 and F-1 aircraft by the two Sargent Fletcher wing-mounted refueling pods. These pods feature a probe-and-drogue refueling system with which the aircraft can be operated as tanker aircraft called KC707.
The aircraft is furthermore able to perform worldwide Aeromedical Evacuation missions. As a peculiarity, the Spanish 707 fits an Air Transport Isolator (ATI) stretcher, a cell that isolates and treats infected victims in flight, e.g. Ebola patients. It can also take cargo containers, pallets, passengers or a combination of all of them.
So far the aircraft has been operated in different missions that include Europe, Middle / Far East, the Balkans, Iraqi, and Africa scenarios as well as diverse countries around the world, where the aircraft has been in use for several civilian relief missions.
The Spanish aircraft codes are: T-17 for transport and TK-17 for the tanker version.
There are plans to replace the B707 with new Airbus A330 MRTT by the beginning of the next decade.
KC707 supplying F-18 (Picture by Nils van de Burg)