Accident Vickers 838 Viscount SE-FOZ,

ASN Wikibase Occurrence # 329229

Date:	Saturday 15 January 1977
Time:	09:05
Type:	Vickers 838 Viscount
Owner/operator:	Linjeflyg
Registration:	SE-FOZ
MSN:	372
Year of manufacture:	1961
Total airframe hrs:	12208 hours
Engine model:	Rolls-Royce Dart 525F
Fatalities:	Fatalities: 22 / Occupants: 22
Aircraft damage:	Destroyed, written off
Category:	Accident
Location:	4,5 km NW of Stockholm-Bromma Airport (BMA) - Sweden
Phase:	Approach
Nature:	Passenger - Scheduled
Departure airport:	Jönköping-Axamo Airport (JKG/ESGJ)
Destination airport:	Stockholm-Bromma Airport (BMA/ESSB)
Investigating agency:	SHK
Confidence Rating:	Accident investigation report completed and information captured

Narrative:
Linjeflyg flight 618 originated at Kristianstad (KID) with stops at Växjö (VXO) and Jönköping (JKG) en route to Stockholm (BMA) in Sweden. On the final leg of the flight, while on approach to Stockholm-Bromma Airport, the aircraft suddenly pitched down from an altitude of 1150 feet. It went into a vertical dive and crashed on a parking lot in the Kälvesta neighbourhood.
Because the no. 2 and no. 3 engines had been running with reduced power for a long time, the anti-ice system temperature was too low.

Probable cause (translated from Swedish):
The accidnt was caused by the stabilizer stalling due to the air flow around it being disturbed by ice accretion.

The reason why ice was formed is that the de-icing system's temperature had been too low due to insufficient power on engines 2 and 3 for a long time. This can be attributed to deficiencies in the pilot's flight manual regarding the operation of the de-icing system, which, in turn, should be due to deficiencies in the flight manual of the manufacturer's aviation authority. Insufficient information in the pilot's flight manual on the effects of ice formation on the stabilizer may also have affected. The pilots have also not been informed of the occurrence of severe ice formation in the Stockholm area.

Accident investigation: