A Eurocopter AS355F1 Twin Squirrel crash in Cheshire, UK, on 22 October, 1996, was a result of the pilot's excessive work load in marginal weather conditions and his inexperience of instrument-flight-rules (IFR) operations, according to the UK Air Accident Investigation Branch (AAIB) official accident report.

The crash at Middlewich, which killed the pilot and all four of the passengers on board, has resulted in the AAIB recommending safety improvements in its report, notably that:

if either the helicopter or its crew are unqualified for IFR flights, stricter weather conditions should be applied before an aircraft is allowed to operate at night under visual flight rules (VFR);

the UK should continue to prohibit any helicopter from carrying out night commercial-air-transport operations under VFR within its airspace.

Source: Flight International