Kh-31

A ramjet-powered missile that homes on the radar trying to detect it. The Kh-31P is the reason Ukrainian Patriot crews cannot leave their radars radiating, and why air defence in Ukraine is as much a problem of emissions discipline as of interceptor stocks.

Overview

The Kh-31, designated AS-17 Krypton by NATO, is a Soviet-designed supersonic missile built around an unusual propulsion arrangement: a solid-fuel rocket booster accelerates it after launch, is discarded, and an integrated ramjet sustainer then carries it to speeds of roughly 1,000 m/s, with later variants assessed at Mach 4 or above. It exists in two fundamentally different guises that share an airframe:

• Kh-31P — the anti-radiation variant, which homes passively on the emissions of enemy air-defence radars. This is a suppression-of-enemy-air-defences (SEAD) weapon.
• Kh-31A — the anti-ship variant, which uses active radar homing against surface vessels.

In Ukraine the Kh-31P is the operationally significant version. Russian Su-35S fighters have been observed carrying Kh-31P and the improved Kh-31PM against Ukrainian radar-dependent systems, including Patriot batteries. It is the weapon that makes radiating expensive.

🔒 The full Kh-31 file is for BattlePolicy Pro members. Below the line: development history, design and capabilities, variants, the combat record, advantages and limitations, comparable systems, outlook, the full specifications table, our sourcing, and the analyst assessment — procurement, suppliers and the BattlePolicy verdict. Unlock the full file with BattlePolicy Pro →