Quick Reaction Alert

Quick Reaction Alert, known colloquially as QRA, is state of readiness and modus operandi of air defence maintained at all hours of the day by NATO, mainly involving the Royal Air Force (RAF).

Some non-NATO countries also maintain QRA, although not necessarily full-time. These include Switzerland, Sweden and Austria.

Pilots on QRA duty are at immediate readiness twenty-four hours a day fully dressed in the Aircrew Ready Room, which are next to the hangars (a hardened aircraft shelter known informally as Q-sheds) which houses the interceptor aircraft, since 2007 the Eurofighter Typhoon. Pilots are on QRA duty around once or twice a month, each a twenty-four-hour shift. Two Typhoon aircraft are on duty, each with two 2,000 litre drop tanks, four Advanced Short Range Air-to-Air Missiles (ASRAAM), and four AIM-120 Advanced Medium Range Air-to-Air Missiles.

Civilian aircraft in the UK are monitored by NATS Holdings at:

Military radar in the UK is controlled by the UK Air Surveillance and Control System (ASACS), looked after by ASACS Force Command. It has Remote Radar Heads (RRH) at:

The radars were Type 93, and are being replaced by the Lockheed Martin AN/FPS-117 system.

Air traffic across Europe is controlled by Eurocontrol in Brussels. Military aircraft from Russia can be tracked across Norway, and reported to the Norwegian Joint Headquarters near Bodø, or the Combined Air Operations Centre 2 (CAOC UE) in Uedem, North Rhine-Westphalia close to the border with The Netherlands. The Russian Tu-95 Bear aircraft originate from the Olenya base on the Kola Peninsula and the Tu-160 Blackjack aircraft come from the Engels-2 base near Saratov.

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