Date:	Monday 22 July 2019
Time:	18:30
Type:	Guimbal Cabri G2
Owner/operator:	HeliGroup Operations Ltd
Registration:	G-CILR
MSN:	1090
Year of manufacture:	2015
Engine model:	Lycoming O-360-J2A
Fatalities:	Fatalities: 0 / Occupants: 1
Other fatalities:	0
Aircraft damage:	Destroyed
Category:	Accident
Location:	Wycombe Air Park (EGTB) -   United Kingdom
Phase:	Standing
Nature:	Private
Departure airport:	Dunkeswell Airport (EGTU)
Destination airport:	Wycombe Air Park (EGTB)
Investigating agency:	AAIB
Confidence Rating:	Accident investigation report completed and information captured

Narrative:
AAIB investigation to Guimbal Cabri G2, G-CILR: Aircraft destroyed by fire due to electrical short circuit, Wycombe Air Park, 22 July 2019. The incident was the subject of an AAIB Investigation, and the following is an excerpt from the AAIB Report, published on 19 March 2020:

"History of the Flight
The helicopter was being flown from Dunkeswell Airfield, Devon, to Wycombe Air Park, Buckinghamshire. Prior to the flight, the helicopter had last flown on 17 June 2019 with no reported issues.

The pilot conducted the pre-flight checks and found the helicopter to be in a satisfactory condition. The fuel level was below the minimum to hover-taxi to the pumps, so the pilot used a jerry can to uplift 20 litres of fuel before initiating the start procedure. When he attempted to start the engine the starter motor would not turn. The pilot thought that the battery may be low on charge due to the elapsed time since the helicopter’s last flight so he charged it using a dedicated 12V DC charger. After charging the battery for approximately 2.5 hours the engine was successfully started. The pilot let the engine to idle for approximately 15 minutes, to further charge the battery, before he hover-taxied to the fuel pumps. Whilst waiting for the battery to charge the pilot contacted Wycombe tower to ask permission to land at the airfield outside of normal operational hours, which was granted.

Once the helicopter was fuelled, the pilot completed inter-flight checks, started the engine and departed Dunkeswell at 1600 without issue. During the flight the pilot made specific note of the ammeter indication to confirm that the alternator was charging the battery. He noticed nothing unusual during the flight.

The pilot made a blind radio call on the Wycombe frequency before the helicopter entered the ATZ to the north of the airfield. After crossing Runway 06/24 the helicopter landed on helicopter pad 10. After landing the pilot commenced the normal shutdown procedure.

He bought the engine to idle, disengaged the clutch, waited 10 seconds and then shut the engine down. As he did so, he noticed a static noise being received on the radio.

He also noticed that the ammeter was at its full negative deflection for approximately 2 seconds before stabilising at around 1/3 negative deflection. In addition the Exhaust Gas Temperature (EGT), which would normally read ‘- - -’ shortly after shutdown, indicated approximately 350°C and the carburettor temperature reading was steadily increasing from 30°C to above 50°C. The pilot applied the rotor brake and shortly before the rotor had stopped the he observed smoke rising over the left side of the helicopter.

He left the helicopter and saw flames coming from within the cowling around the left side of the main rotor mast. He went back to the helicopter and pulled the emergency fuel shut-off and switched off all electrical switches before retrieving the on-board fire extinguisher.

He expended its contents, half into the mast cowling and half onto the underside of the engine, but this had no effect. He then retrieved a personal bag from the cockpit before retreating to a safe distance.

A witness called the emergency services and a local fire and rescue appliance arrived approximately ten minutes later. The fire was extinguished but by this time the helicopter had been destroyed. There were no injuries"

Safety actions taken by the helicopter manufacturer:
● A Service Bulletin was issued by the helicopter manufacturer to inspect the clips to ensure correct installation.
● The helicopter manufacturer has completed a redesign of the clipping system to ensure the cable clipping cannot be installed incorrectly. The new design of clip is being fitted to new production helicopters and will be available via service bulletin from the manufacturer".

G-CILR was completely burnt out. As a result the registration was cancelled by the CAA (and the airframe de-registered) on 12 February 2020 as "Destroyed"

1. AAIB Correspondence Report: https://www.gov.uk/government/publications/aaib-current-field-investigations/air-accidents-investigation-branch-current-field-investigations
2. AAIB Annual Safety Review 2020 p.106: https://assets.publishing.service.gov.uk/media/60d2e72ed3bf7f4bd4662d67/Annual_Safety_Review_2020.pdf
3. https://www.bbc.co.uk/news/uk-england-beds-bucks-herts-51959648
4. https://www.helis.com/database/cn/40645/
5. https://en.wikipedia.org/wiki/Wycombe_Air_Park

Built 2015. First registered (from new) as G-CILR to the 1st owner from 30 January 2015. Re-registered to the 2nd owner 12 April 2019. Total amount of flying hours accumulated on the airframe: 894 as at 9 May 2019.

After the incident at Booker (Wycombe Air Park) on 22 July 2019, G-CILR was completely burnt out. As a result the registration was cancelled by the CAA (and the airframe de-registered) on 12 February 2020 as "Destroyed"

Photo: AAIB

G-CILR Guimbal Cabri G2 Helicopter at Gloucestershire Airport (GLO/EGBJ) 21 July 2018

Date/time	Contributor	Updates
22-Feb-2020 20:09	sharla82	Added
19-Mar-2020 11:00	harro	Updated [Photo, Accident report, ]
19-Mar-2020 11:07	harro	Updated [Operator, Location, Nature, Accident report, ]
26-Jun-2021 22:32	Dr. John Smith	Updated [Source, Narrative, ]
02-Sep-2024 05:53	Dr. John Smith	Updated [Operator, Location, Source, Embed code, Narrative, Category, ]