 | This articleneeds additional citations forverification. Please helpimprove this article byadding citations to reliable sources. Unsourced material may be challenged and removed. Find sources: "Martin X-23 PRIME" – news ·newspapers ·books ·scholar ·JSTOR(September 2024) (Learn how and when to remove this message) |
| X-23A PRIME | |
|---|---|
 Preserved X-23A PRIME at USAF Museum, Dayton, Ohio | |
| General information | |
| Type | Lifting body |
| National origin | United States |
| Manufacturer | Martin Marietta |
| Status | Out of service |
| Primary user | United States Air Force |
| Number built | 3 |
| History | |
| First flight | 21 December 1966 |
| Retired | 19 April 1967 |
| Variant | Martin Marietta X-24 |
TheMartin X-23A PRIME (Precision Reentry Including Maneuvering reEntry) (SV-5D) is a smalllifting-bodyre-entry vehicle tested by theUnited States Air Force in the mid-1960s. UnlikeASSET, primarily used for structural and heating research, the X-23A PRIME was developed to study the effects of maneuvering during re-entry ofEarth's atmosphere, including cross-range maneuvers up to 617 nmi (710 mi; 1,143 km) from theballistic track.
Each X-23A was constructed fromtitanium,beryllium,stainless steel, andaluminum. The craft consisted of two sections—the aft main structure and a removable forward "glove section". The structure was completely covered with a Martin-developedablativeheat shield 0.75 to 2.75 in (19 to 70 mm) thick, and thenose cap was constructed ofcarbonphenolic material.[1][2]
Aerodynamic control was provided by a pair of 12 in × 12 in (305 mm × 305 mm) lowerflaps, and fixed upper flaps andrudders. Anitrogen-gasreaction control system was used outside the atmosphere. AtMach 2 adrogueballute deployed and slowed the vehicle's descent. As it deployed, its cable sliced the upper structure of the main equipment bay, allowing a 47 ft (14 m) recoverychute to deploy. It would then berecovered in midair by a specially-equippedJC-130B Hercules aircraft.[1][2]
The first PRIME vehicle was launched fromVandenberg AFB on 21 December 1966 atop anAtlas SLV-3launch vehicle. This mission simulated alow Earth orbit reentry with a zero cross-range. The ballute deployed at 99,850 ft (30,434 m), though the recovery parachute failed to completely deploy. The vehicle crashed into the Pacific Ocean.[1][2]
The second vehicle was launched on 5 March 1967. This flight simulated a 654-mile (1053-kilometre) cross-range reentry, and banking at hypersonic speeds. The recovery parachute deployed properly and was located by two of the deployed recovery aircraft. During an inspection fly-by of the descending parachute system it was seen that reefing cutters had failed to actuate. These cutters are on the harness suspending the vehicle from the parachute to ensure stability of the vehicle behind the JC-130B recovery aircraft during reel-in, and permit safely boarding the vehicle. As a result, the parachute and vehicle were allowed to descend to the sea. Subsequently, the vehicle separated from its flotation "balloon" in the rough seas and, with the parachute, sank before a nearby ship could arrive to retrieve it from the ocean.[1][2]
The final PRIME mission was flown on 19 April 1967, and simulated re-entry from low Earth orbit with a 617 nmi (710 mi; 1,143 km) cross-range. This time, all systems performed perfectly, and the X-23A was successfully recovered. An inspection by a USAF-Martin team reported the craft "ready to fly again", although no later missions were carried out. The third X-23A is now on display at theNational Museum of the United States Air Force atWright-Patterson Air Force Base in Ohio.[1][2]
Data from The X-planes : X-1 to X-29[2][3]
General characteristics
Performance
Aircraft of comparable role, configuration, and era
