Boeing EC-135 / EC-18 ARIA
Summary
| Category | Other aircraft |
| Origin country | 🇺🇸 United States |
| First flight | 1 January 1961 |
| Year of introduction | 1968 |
| Number produced | 45 units |
| Average unit price | $150 million |
Description
The ARIA (Advanced Range Instrumentation Aircraft) program was established in the 1960s to meet the telemetry measurement and tracking needs of the US space program. It involved modifying several Boeing 707 aircraft to serve as advanced instrumentation platforms. These modified aircraft included EC-135Bs (modified C-135s) and EC-18Bs (former American Airlines converted Boeing 707-320s).
The initial need arose from the necessity to establish a global network of telemetry measurement and tracking stations for the Apollo lunar missions, as well as for ballistic and orbital missile testing. To overcome geographical constraints and the slow speed of specialized ships, it was decided to develop a fast aircraft capable of providing coverage for these missions.
NASA and the US Department of Defense signed a contract with McDonnell Douglas and Bendix to modify eight Boeing C-135 Stratolifter cargo aircraft into Apollo/Range Instrumentation Aircraft (A/RIA). The first operational aircraft, the EC-135N A/RIA, were deployed in January 1968. The US Air Force was responsible for maintaining and operating these aircraft until the end of the Apollo program in 1972. Subsequently, the US Air Force renamed the A/RIA program to Advanced Range Instrumentation Aircraft - ARIA, and new missions were added, such as telemetry measurements, international treaty verifications, and measurements related to space launches and ballistic missiles.
Each modified ARIA aircraft featured external and internal modifications. External modifications included a bulbous nose housing a steerable antenna, wing and fuselage antennas, and satellite transmission equipment. Internal modifications included the installation of electronic instrumentation, known as Prime Mission Electronic Equipment (PMEE), distributed across eight subsystems.
The typical crew comprised six to nine PMEE specialists, a mission commander, two pilots, a navigator, and a flight engineer. ARIA teams needed to be self-sufficient in maintenance during deployments, and each mission required thorough three-day preparation to configure the onboard electronic instruments.
Telemetry data was primarily collected in oceanic areas or remote regions where ground stations were not available. The data was transmitted in real-time via UHF satellite for live tracking and recorded on magnetic tape for further analysis.
Over time, the high cost of this technology, along with advancements in satellites, led the US Air Force to transfer the ARIA missions to other platforms such as the EC-8 Joint-STARS. By 1997, the ARIA fleet consisted of three EC-135Es and three EC-18Bs, but only two EC-135Es remained in active service. In 2001, the last EC-135E was retired and put on display at the National Museum of the US Air Force. The two remaining EC-18Bs were retired from ARIA service in 2001 and transferred to the Joint STARS program before being permanently retired in 2003.
Technical specifications
| Version: EC-135E | |
|---|---|
| Crew | At least 11 |
| Operational range | 8300 km (5157 mi) |
| Maximum speed | 927 km/h (576 mph) |
| Wing area | 223 m² (2400.3 sqft) |
| Wingspan | 31.6 m (103.8 ft) |
| Height | 12.7 m (41.7 ft) |
| Length | 43.1 m (141.5 ft) |
| Service ceiling | 10058 m (32999 ft) |
| Max. takeoff weight | 136304 kg (300499 lbs) |
| Powerplant | 4 × turbojets Pratt & Whitney TF33-PW-102 delivering 8165 kgp |
Current operating countries
No country is operating the EC-135 / EC-18 ARIA in 2025.
All operators
Photo of EC-135 / EC-18 ARIA
