12/31/2007. Remarks by Johan Visschedijk: "First of two AWACS prototypes, 71-1407 was first flown on February 9, 1972. Above it is pictured about to hook up to the Boeing 717-100A NKC-135A Stratotanker 55-3135 from the 4950th Test Wing at Edwards AFB.

Boeing 707-320B EC-137D (71-1407)

Boeing 707-320B EC-137D (71-1407)

After completing testing the two EC-137Ds were brought up to production standard and redesignated E-3A Sentry. Later they were converted to E-3Bs, the conversion of 71-1407 was completed on July 19, 1984."