Logan SF34 near Shetland Islands on Mar 4th 2014, icing problems

A Logan Air Saab 340B on behalf of FlyBe, registration G-LGNB performing flight LOG-6770/BE-6770 from Aberdeen,SC to Shetland Islands Sumburgh,SC (UK) with 25 passengers, had departed on time and was enroute at FL190 east of Kirkwall,SC and south of Shetland Islands' Sumburgh Airport, when the crew declared emergency due to icing problems, the aircraft descended to FL170. The aircraft subsequently climbed to FL200 and continued towards Sumburgh Airport, the transponder's altitude "jumped" to FL080 feet and back to FL200 within seconds. While descending towards Sumburgh the crew aborted the descent at FL100 and decided to return to Aberdeen, but ultimately to divert to Kirkwall. The aircraft diverted to Kirkwall maintaining FL100 enroute, the transponder showed deviations between FL068 and FL104 over a period of 4 minutes before showing a stable FL100 again, and landed safely at Kirkwall at about 08:55L (08:55Z) about one hour past scheduled time of landing at Sumburgh.

The airline reported there had been a problem with the airframe's de-icing systems which affected the landing performance. The crew initially intended to return to Aberdeen but due to deteriorating weather at Aberdeen finally decided to divert to Kirkwall.

Sumburgh Airport features a runway 09/27 of 1500 meters/4920 feet and a runway 15/33 of 1425 meters/4680 feet length. Kirkwall features a runway 09/27 of 1430 meters/4690 feet length and a runway 14/32 of 680 meters/2230 feet length.

Metars Shetland Islands:

EGPB 040950Z 15012KT 9999 FEW015 FEW018CB 07/04 Q0993 NOSIG

EGPB 040920Z 17015KT 9999 FEW014 FEW018CB 07/04 Q0993 NOSIG

EGPB 040850Z 17014KT 9999 FEW014 FEW018CB 06/04 Q0993 NOSIG

EGPB 040820Z 13005KT 9999 VCSH FEW011 BKN028 06/04 Q0992 NOSIG

EGPB 040750Z 16004KT 9999 FEW011 SCT022 05/04 Q0992 NOSIG

EGPB 040720Z 18005KT 9999 -RA FEW011 BKN024 05/04 Q0992 NOSIG

EGPB 040650Z 20005KT 9999 -RA FEW012 BKN024 05/04 Q0992 NOSIG

EGPB 040620Z 20007KT 9999 -RA BKN018 05/04 Q0991 NOSIG

EGPB 040550Z 20009KT 9999 FEW009 BKN017 06/04 Q0991 NOSIG

EGPB 040520Z 17008KT 9000 FEW010 SCT014 BKN018 06/05 Q0991 NOSIG

Metars Aberdeen:

EGPD 040950Z 20012KT 9999 -RA SCT012 BKN019 05/03 Q0991 NOSIG

EGPD 040920Z 19014KT 9999 SCT011 BKN017 05/03 Q0990 NOSIG

EGPD 040850Z 17016G26KT 9000 -RA SCT010 BKN017 04/03 Q0990 NOSIG

EGPD 040820Z 17015KT 9999 -RA FEW010 SCT013 BKN021 04/03 Q0990 NOSIG

EGPD 040750Z 17014KT 9000 -RA SCT017 BKN023 03/02 Q0991 NOSIG

EGPD 040720Z 17008KT 9000 -RA FEW012 SCT018 BKN022 03/02 Q0991 NOSIG

EGPD 040650Z 16006KT 9999 -RA FEW018 SCT022 BKN041 02/01 Q0991 NOSIG

EGPD 040620Z 18007KT 9999 FEW025 01/00 Q0992 NOSIG

EGPD 040550Z 18007KT 9999 FEW044 01/00 Q0992 NOSIG

EGPD 040520Z 00000KT 9999 FEW041 M01/M01 Q0992 NOSIG

Metars Kirkwall:

EGPA 040950Z 14012KT 9999 VCSH FEW015TCU SCT023 BKN034 06/04 Q0991

EGPA 040920Z 14013KT 9999 FEW015TCU SCT020 06/03 Q0991

EGPA 040850Z 12009KT 9999 FEW015TCU 06/04 Q0991

EGPA 040820Z 13008KT 9999 FEW015 05/03 Q0991

EGPA 040750Z 14006KT 9999 FEW010 02/01 Q0991

EGPA 040720Z 15006KT 9999 FEW012 02/01 Q0991

EGPA 040650Z 16006KT 9999 FEW010 02/01 Q0990

EGPA 040620Z 18006KT 9999 FEW020 02/01 Q0990

EGPA 040550Z AUTO 18007KT 9000 NCD 02/01 Q0990

EGPA 040520Z AUTO 18008KT 7000 NCD 03/02 Q0990