Date:	Friday 4 March 2016
Time:	09:15
Type:	ATR 72-500 (72-212A)
Owner/operator:	Aurigny Air Services
Registration:	G-COBO
MSN:	852
Fatalities:	Fatalities: 0 / Occupants: 31
Aircraft damage:	None
Category:	Serious incident
Location:	On departure from Manchester Airport (MAN/EGCC) to Guernsey -   United Kingdom
Phase:	En route
Nature:	Passenger - Scheduled
Departure airport:	Manchester International Airport (MAN/EGCC)
Destination airport:	Guernsey Airport, Channel Islands (GCI/EGJB)
Investigating agency:	AAIB
Confidence Rating:	Accident investigation report completed and information captured

Narrative:
AAIB investigation to ATR 72-212 A, G-COBO: Pitch control difficulty after departing Manchester Airport in icing conditions, diverted to East Midlands Airport, 4 March 2016. The incident was deemed to be a "serious incident" - serious enough to warrant an AAIB Investigation, and the following is the summary from the AAIB Report:

"The aircraft arrived at Manchester Airport from Guernsey and remained on the ground for more than an hour, while it was snowing and the temperature was 0ºC. The flight crew decided no de-icing or anti-icing treatment was needed, as they did not consider the snow was settling on the aircraft, and the aircraft subsequently departed to return to Guernsey.

During the takeoff, the commander exerted less aft pressure on the control column, to rotate the aircraft, than he expected and maximum nose-down pitch trim was then needed to maintain the appropriate climb attitude. The autopilot was engaged four times but, on each occasion, it disengaged, as designed, and the commander had to apply continuous forward pressure on the control column to retain the desired pitch attitude, as the climb proceeded.

Once at the cruising level, the commander decided he was having to exert excessive forward pressure on the control column and he elected to divert to East Midlands Airport (EMA). While descending, the aircraft flew out of icing conditions and the control difficulties dissipated. The crew assessed that ice contamination had caused the problem and they made a normal landing.

No ice was found on the aircraft during a post-flight inspection but analysis by the manufacturer concluded that, from the start of the flight until the latter stages of the descent, the airflow over the horizontal tailplane and elevator was disrupted by ice contamination.

=AAIB Conclusion
The investigation concluded that ice contamination affected the tailplane and caused pitch control difficulty after the aircraft rotated, on departure. The evidence indicated that this would have been avoided if the aircraft had been de-iced/anti-iced and then inspected carefully before flight.

The crew considered, before parking, that de-icing was probably going to be unnecessary. It may then have become difficult for them to change their assessment because of ‘Confirmation bias’, even though they were in freezing conditions and snow was falling. A contributory factor may have been the crew’s lack of experience operating aircraft in such conditions.

The commander optimistically thought that lying snow would blow off the aircraft before rotation; an assessment that was flawed and a possible reflection on the training the pilots had received for such winter conditions. The operator has recognised that recurrent winter training for pilots may have been over-reliant on self-study and has taken remedial action

=Damage sustained to airframe=
Per the AAIB report "None". The aircraft was checked over at East Midlands Airport (EMA) and then returned to service

1. AAIB Final Report: https://assets.publishing.service.gov.uk/media/587dfa40ed915d0b12000141/ATR_72-212_A_G-COBO_02-17.pdf
2. https://aerossurance.com/safety-management/atr72-icing-cognitive-bias/
3. https://www.flightglobal.com/flawed-bid-to-outclimb-icing-led-to-serious-atr-upset/126474.article
4. Incident near Guernsey, Channel Islands 21 December 2016: https://aviation-safety.net/wikibase/192390
5. Incident at Manchester Airport 17 September 2017: https://aviation-safety.net/wikibase/199749
6. https://en.wikipedia.org/wiki/Manchester_Airport#

G-COBO was built in 2009 and was first registered as such in the UK (\\\'from new\\\') on 5 March 2009. In service with Aurigny Air Services G-COBO was involved in three notifiable incidents: on 4 March 2016 (as per the above) on 21 December 2016 and on 17 September 2017 (see separate ASN entries)

The registration G-COBO was cancelled 17 April 2020 upon transfer to France as F-WNUI on 8 February 2020, when it was \\\'traded in\\\' to ATR - Avions de Transport Regional. As at 9 March 2020, G-COBO had accumulated a total of 20,350 flying hours on the airframe. The aircraft next saw service in South Korea from 22 June 2021 with Hi Air as HL5245, before being \\\'traded in\\\' for a second time by to ATR, this time acquiring the Manx (Isle of Man) registration M-NOEL on 20 December 2023.

Other occurrences involving this aircraft

21 December 2016

G-COBO

Aurigny Air Services

0

near Guernsey, Channel Islands, 5 nm N of reporting point ORTAC

non

G-COBO: Aerospatiale ATR 72-500 (72-212A) of Aurigny Air Services departing Runway 27 at East Midlands Airport (EMA) 30 March 2016

Date/time	Contributor	Updates
06-May-2024 06:20	Dr. John Smith	Added
06-May-2024 06:21	ASN	Updated [Source, Accident report]