They decided that they needed the cannons in Afghanistan. A 500 lb bomb against a guy in a pickup near civilians will cause too much collateral damage.

They discovered this in Sierra Leone, with their Harriers, which had had the cannons pulled, and sometimes the target was just a guy on a bicycle.

It was a false economy in the first place.

Cannons will be operable on all UK RAF Eurofighter Typhoons

The 27mm Mauser cannons on all UK Royal Air Force Eurofighter Typhoons will be operable, and will only require ammunition and loading equipment for them to work, contrary to our report last week (Flight International, 17-23 August). The UK Ministry of Defence says it will spend up to £6 million ($11 million) on support equipment, training and ammunition for those aircraft needed for a deployment where cannons were necessary. The timeframe for enabling pilots to use the cannon is two weeks, or similar to the time required for a force to deploy for UN missions or similar operations, says the MoD.

Originally, only the UK’s first 55 Eurofighters were to have guns fitted (Flight International, 9-15 May 2000). The decision to not enable those guns stemmed from the UK’s current air warfare doctrine, which specifies stand-off weapons. “The decision to retain operational flexibility was made in early 2003 after a detailed assessment of the costs of ballast compared with guns,” says the MoD. Ballast would have been needed to replace the gun mass as the aircraft’s flight-control system took into account the presence of the gun. An assessment into the use of ballast for the UK’s planned remaining 177 Eurofighters, carried out by UK Eurofighter partner company BAE Systems, concluded that guns, and not ballast, was the better option. The MoD estimates the decision will save £10 million a year by avoiding training and maintenance costs and ammunition supply.

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