Investigations continue into the crash of a Eurocopter EC135T2 helicopter operated by Scottish police that crashed through the roof of a busy city centre pub in Glasgow at 22:25 on Friday, 29 November, killing at least nine people and at one point hospitalising more than 30.

The fuselage has now been removed from the crash site and will be transported to the UK Air Accidents Investigation Branch headquarters in Farnborough in the south of England.

Eurocopter has dispatched two experts to assist investigators. Bond Air Services,who operated the aircraft on behalf of the police, is also assisting the parallel investigations being conducted by the AAIB and Police Scotland, under the direction of the Crown Office and Procurator Fiscal Service.

All three occupants of the aircraft (G-SPAO) died in the crash at the Clutha Vaults pub: pilot Dave Traill, a Bond employee, and police constables Tony Collins and Kirsty Nelis.

Deputy chief constable Rose Fitzpatrick describes Traill as “very much part of the Police Scotland team”. She adds: “I would like to pay tribute to all three and recognise the important contribution they made to our public service and to the communities they have served.”

Flightglobal's Ascend Online database lists the helicopter as a 2007-built example which had accumulated 4,401h.

On 17 May 2012, EASA issued an emergency airworthiness directive relating to EC135 helicopters after a crack was detected on the lower hub-shaft flange of a main rotor hub-shaft. Further inspections later identified an additional three affected helicopters, leading to EASA in October that year to mandate pre-flight visual inspections of the affected area. However, there is no suggestion that this issue played a part in the Glasgow crash.

According to Flightglobal Ascend Online data there are 765 civil-registered EC135s in operation globally, with the vast majority used in the EMS role in North America. Eurocopter says that since first delivery in 1996, the EC135 has accumulated 2.9 million flight hours, including almost 400,000h in the last 12 months.

The EC135T2 – the variant which crashed in Glasgow – replaced the T1 in production in August 2002.

In the UK, including Scotland, 57 EC135s are in operation: 20 by police, 20 for emergency medical services, seven for utility companies and 10 in private/business use. Bond is by far and away the largest single operator of the type, with 23 in service and a further seven aircraft on order, according to Ascend Online.

Eurocopter describes the EC135 as the “backbone of the UK’s emergency services”, flying 15,000 missions annually. UK police perform some 19,000h on the EC135 each year.