| R-4 AA-5 Ash | |
| Origin: | Soviet Union |
| Type: | Heavy air-to-air missile |
| Is Missile: | yes |
| Service: | 1963-1990 |
| Used By: | Soviet Air Forces |
| Manufacturer: | Bisnovat |
| Spec Label: | R-4R |
| Weight: | 492.5kg (1,085.8lb) |
| Length: | 17feet |
| Diameter: | 310mm |
| Filling: | High explosive |
| Filling Weight: | 53kg (117lb) |
| Engine: | Solid-fuel rocket |
| Vehicle Range: | 2kmto25kmkm (01milesto16mileskm) |
| Speed: | Mach 1.6 |
| Guidance: | Semi-active radar homing (R-4R) Infrared homing (R-4T) |
| Launch Platform: | Tu-128 |
The Bisnovat (later Molniya) R-4 (NATO reporting name AA-5 'Ash') was an early Soviet long-range air-to-air missile. It was used primarily as the sole weapon of the Tupolev Tu-128 interceptor, matching its RP-S Smerch ('Tornado') radar.
Development of the R-4 began in 1959, initially designated as K-80 or R-80, entering operational service around 1963, together with Tu-128. Like many Soviet weapons, it was made in both semi-active radar homing (R-4R) and infrared-homing (R-4T) versions. Standard Soviet doctrine was to fire the weapons in SARH/IR pairs to increase the odds of a hit. Target altitude was from 8 to 21 km. Importantly for the slow-climbing Tu-128, the missile could be fired even from 8 km below the target.
In 1973 the weapon was modernized to R-4MR (SARH) / MT (IR) standard, with lower minimal target altitude (0.5–1 km),[1] improved seeker performance, and compatibility with the upgraded RP-SM Smerch-M radar.
The R-4 survived in limited service until 1990, retiring along with the last Tu-128 aircraft.