Date:	07-NOV-2016
Time:	06:21
Type:	Avro RJ100
Owner/operator:	BRA - Braathens Regional Airlines
Registration:	SE-DSV
MSN:	E3250
Fatalities:	Fatalities: 0 / Occupants: 55
Other fatalities:	0
Aircraft damage:	None
Category:	Serious incident
Location:	near Gothenburg/Landvetter Airport -   Sweden
Phase:	Initial climb
Nature:	Passenger - Scheduled
Departure airport:	Gothenburg/Landvetter Airport
Destination airport:	Stockholm/Bromma Airport
Investigating agency:	SHK Sweden
Confidence Rating:	Accident investigation report completed and information captured

Narrative:
The incident occurred during a commercial flight from Gothenburg/Landvetter Airport. The aeroplane was operated by Braathens Regional Aviation (BRA). The aeroplane had been parked outside for approximately 40 hours before the incident and was heavily contaminated with precipitation of snow and ice. A one-step de-icing of wings, stabiliser, rudder and fuselage was ordered by the commander. The de-icing was performed by a subcontracted company.
Shortly after take-off, heavy vibrations occurred at an indicated airspeed of around 195 knots. The commander took control of the aeroplane and disconnected the autopilot while the co-pilot made a distress call to air traffic control.
The indicated airspeed was reduced whereby the vibrations ceased. The crew then decided to abort the flight and return to the airport. Thereafter, the speed was increased again and the vibrations returned until the speed was reduced a second time. The engineers of the company inspected the airplane after landing and discovered extensive ice coverage on multiple flight control surfaces.
According to the investigation, the aircraft type appears to be sensitive to mass balances in the control system. This means that even very thin layers of ice are sufficient to make the flight control system unbalanced beyond the tolerances specified in the aircraft’s approved maintenance manuals. In this case, the ice contaminations on the aircraft were relatively extensive. Against this background, SHK has concluded that the vibrations were due to the unbalance of the elevator system that arose due to the ice contamination.
It is apparent from the investigation that the personnel who were to inspect the aircraft prior to the flight did not detect all ice contamination, which meant the de-icing order did not cover all of the ice contamination, and that there were shortcomings in the de-icing actually carried out.
The incident was partly caused by the fact that the operator lacked enough detailed procedures for performing a complete contamination inspection, and that the existing routine’s was not fully applied, partly by the fact that the operator had not properly checked, evaluated and controlled the subcontractor’s working methods.
A contributing factor was that the de-icing operation had insufficient organisational support to help the staff to resist requests of departure on time and to ensure that the de-icing was properly executed despite actual or experienced time shortage.



7 Dec 2012

SE-DSV

Malmö Aviation

0

Around Växjö

non

Safety recommendation RL 2017:10 R1 issued by SHK to ICAO
Safety recommendation RL 2017:10 R2 issued by SHK to EASA
Safety recommendation RL 2017:10 R3 issued by SHK to Swedish Transport Agency

Date/time	Contributor	Updates
16-Dec-2017 18:01	harro	Added