The US Navy initially preferred ex-airline Douglas DC-8s as test-beds (EC-24 163050 illustrated), but took NKC-135s as well.

Самолёты на фотографии: Aircrafts on the photo: Douglas DC-8 - СШАUSA - 1958

In addition to working as a tanker test-bed, NKC-135E 55-3135 also provided tanker support for other programmes.

Самолёты на фотографии: Aircrafts on the photo: Boeing KC-135 Stratotanker / C-135 Stratolifter - СШАUSA - 1956McDonnell Douglas F/A-18A Hornet - СШАUSA - 1978

NKC-135A 55-3122 soon after entering storage at Davis-Monthan in late 1993. It had previously been flown by the 4950th TW.

Самолёты на фотографии: Aircrafts on the photo: Boeing KC-135 Stratotanker / C-135 Stratolifter - СШАUSA - 1956

Close-up of the ALL NKC-135A 55-3123 on the museum ramp at 'Wright-Patt'.

Самолёты на фотографии: Aircrafts on the photo: Boeing KC-135 Stratotanker / C-135 Stratolifter - СШАUSA - 1956

In company with several J/NKC-135As used for recording high-altitude events, 55-3124 had a number of large optically flat windows along its fuselage.

Самолёты на фотографии: Aircrafts on the photo: Boeing KC-135 Stratotanker / C-135 Stratolifter - СШАUSA - 1956

Eleven optical windows and a large fairing were installed on NKC-135A 55-3127 initially for Project 'Skyscraper'. Tlte upper surface of the port wing was painted black to reduce glare.

Самолёты на фотографии: Aircrafts on the photo: Boeing KC-135 Stratotanker / C-135 Stratolifter - СШАUSA - 1956

While it is best known as an icing tanker NKC-135A 55-3128 was also used to test the AN/APQ-140 radar in an enlarged nose radome.

Самолёты на фотографии: Aircrafts on the photo: Boeing KC-135 Stratotanker / C-135 Stratolifter - СШАUSA - 1956

Этот JKC-135A входил в число трех самолетов «Vomit Comet», использовавшихся для подготовки астронавтов, а с 1979 года испытывал винглеты.
NASA flew 55-3129 as a research aircraft from mid-1979 to assess the benefits of winglets.

Самолёты на фотографии: Aircrafts on the photo: Boeing KC-135 Stratotanker / C-135 Stratolifter - СШАUSA - 1956

'Big Crow’ NKC-135E 55-3132 flew missions during Operation ‘Iraqi Freedom', deploying to Souda Bay on Crete from March 17, 2002.

Самолёты на фотографии: Aircrafts on the photo: Boeing KC-135 Stratotanker / C-135 Stratolifter - СШАUSA - 1956

Several C-135s associated with nuclear readiness testing had large numbers of windows on one side, including NKC-135A 55-3135.

Самолёты на фотографии: Aircrafts on the photo: Boeing KC-135 Stratotanker / C-135 Stratolifter - СШАUSA - 1956

After being assigned as a tanker test-bed, many of the smaller windows on the starboard side of 55-3135 were filled in. Pictured at Edwards AFB as an NKC-135E, 1997.

Самолёты на фотографии: Aircrafts on the photo: Boeing KC-135 Stratotanker / C-135 Stratolifter - СШАUSA - 1956

Impressive line-up at Edwards, 1997.

Самолёты на фотографии: Aircrafts on the photo: Boeing EC-135E / EC-18 ARIA / Condor - СШАUSA - 1968Boeing KC-135 Stratotanker / C-135 Stratolifter - СШАUSA - 1956

NKC-135E 55-3135 at Edwards, 1997.

Самолёты на фотографии: Aircrafts on the photo: Boeing KC-135 Stratotanker / C-135 Stratolifter - СШАUSA - 1956

'Navy King Crow I' was the second NKC-135A flown on behalf of the US Navy.

Самолёты на фотографии: Aircrafts on the photo: Boeing KC-135 Stratotanker / C-135 Stratolifter - СШАUSA - 1956

Possibly the most famous NKC-135A test-bed was the Airborne Laser Laboratory, the first to destroy a missile in flight.

Самолёты на фотографии: Aircrafts on the photo: Boeing KC-135 Stratotanker / C-135 Stratolifter - СШАUSA - 1956

KC-135A 55-3129 is seen painted in Wright Air Development Center, Air Research and Development Command markings prior to being delivered by Boeing, before becoming a JKC-135A.

Самолёты на фотографии: Aircrafts on the photo: Boeing KC-135 Stratotanker / C-135 Stratolifter - СШАUSA - 1956

top to bottom: NKC-135A 55-3121; NKC-135A 55-3123 HEL; NKC-135A 55-3123 ALL; NKC-135A 55-3128; NKC-135A 55-3129 NASA winglets; NKC-135A 55-3132 SLAR test-bed; NKC-135A 55-3132 'Big Crow'; NKC-135A 55-3124 celestial navigation research; NKC-135A US Navy FEWSG; NC-135A 60-0370 nuclear; NC-135A 60-0376 'Piccolo Tube'; NC-135B 61-2669 SATCOM test-bed.

Самолёты на фотографии: Aircrafts on the photo: Boeing KC-135 Stratotanker / C-135 Stratolifter - СШАUSA - 1956

Самолёты на фотографии: Aircrafts on the photo: Boeing YAL-1A - СШАUSA - 2002

NKC-135s have been involved in extensive flight testing for the 747-based YAL-1A ABL.

Самолёты на фотографии: Aircrafts on the photo: Boeing YAL-1A - СШАUSA - 2002

EC-135E 60-0374 at Tinker in 1995.

Самолёты на фотографии: Aircrafts on the photo: Boeing EC-135E / EC-18 ARIA / Condor - СШАUSA - 1968

For the ARIA mission the EC-135Ns and 'Es had a high-frequency antenna on the tip of the starboard wing.

Самолёты на фотографии: Aircrafts on the photo: Boeing EC-135E / EC-18 ARIA / Condor - СШАUSA - 1968

The most distinctive feature of the ARIAs was the large nose radome, within which was one of the largest dishes ever installed on an aircraft.

Самолёты на фотографии: Aircrafts on the photo: Boeing EC-135E / EC-18 ARIA / Condor - СШАUSA - 1968

AFMC EC-135E 61-0326 at Edwards, April 1997.

Самолёты на фотографии: Aircrafts on the photo: Boeing EC-135E / EC-18 ARIA / Condor - СШАUSA - 1968

Moody image of EC-135E 61-0326 at Edwards in 1997.

Самолёты на фотографии: Aircrafts on the photo: Boeing EC-135E / EC-18 ARIA / Condor - СШАUSA - 1968

EC-135N (top) and EC-135N ALOTS.

Самолёты на фотографии: Aircrafts on the photo: Boeing EC-135E / EC-18 ARIA / Condor - СШАUSA - 1968