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= SAS A20N Incident at Tromsø on Feb 12th 2023 = [TOC]

Airbus A320 Neo Plane (ICAO Type Designator of the plane: A20N) was involved in an air safety incident in 2023. The incident occurred on the 12th of February in 2023. The flight SK-4434 took off from Oslo Gardermoen and planned to land in Tromsø Airport Langnes (ICAO: ENTC) after two hours, i. e. 20:30 at local time (18:30 in Zulu). The distance was 602 nm, so, the predicted flight duration was 1:50. While the aircraft was approaching the runway 19 (runway length: 2400 meters) it received a lightning strike which caused the loss of thrust on one of the engines (LEAP). The crew needed to declare "Mayday Mayday" and initiated a go around procedure from about 1200 feet MSL. Moreover, the aircraft needed to abort the first landing attempt because of the severe weather conditions like the strong wind and icing in the air. Then the aircraft climbed to FL110, subsequently FL160, and returned to Tromsø Airport for a safe landing on runway 19 on the second approach. The flight was prolonged approximately 30 minutes. The route is presented in the picture on the right.

Background
SAS A20N is Airbus A320 Neo Plane flown by SAS Scandinavian Airlines. The aircraft is registered in Sweden, the registration number is SE-ROD.

Airbus A320 has a capacity for 189 passengers. Airbus A320 Neo is a twin engine plane. The mounted engines: Pratt & Whitney's PurePower PW1100G-JM geared turbofan, and CFM International's LEAP-1A, both of which provide outstanding operational, economic, and environmental performance. These engines have a high power requirements and can generate a thrust of 121 kN/27,120 lbf. Actually, 'Neo' represents the "new engine option" which improves Airbus A320 Ceo. Airbus A320 Neo was launched in 2010, and carried out the first flight in 2014. So, it is a technologically pretty recent and advanced as well as capacious aircraft in 2023. The wear off and fatigue should not be a factor in the issues of the engine.

An interesting detail is that on the same day another SAS A20N needed to reject takeoff from Tromsø Airport due to difficulties with directional control.

Meteorological Data
METAR data are provided below:  From METAR it is possible to deduce that the west or south-west wind was pretty strong: the direction was varying 250-270, the speed varying from 19 kt to 30 kt with the gusts till 48 kt. Temporary the wind speed was predicted to reach 45 kt with the gusts till 68 kt. So, the wind speeds were dramatically high.

The average speed of a severe thunderstorm might be 27 kt (50 km/h), the average maximum can be 29-35 kt (54-64 km/h). During the later stages, some storms exhibit strong downdrafts with winds that can top 161 kilometres per hour (140 kt). Storms reach hurricane strength when winds reach 74 mph. 74 mph is about 64 kt, thus, the wind gusts were speeding almost to the hurricane level (it is assigned as Category 1 hurricane speed according Saffir-Simpson Hurricane scale). Undoubtedly, these maximum wind gusts speeds were a serious hazard for Airbus A320 during the flight SK-4434.

SHSNRA stands for light showers, snow and rain. The sky was covered by cumulonimbus. Air pressure was dropped as well significantly, i. e. to 989 hPa. Actually, these meteorological conditions are obviously related to the thunderstorm.

TAF data is provided below from here: The expected wind direction was 260-280 kt and the speed 20-35 kt with the temporarily forecasted wind gusts of 50 kt. TAF predictions were less severe in comparison with METAR, moreover, METAR were issued and updated more frequently.

The maps illustrates the meteorological conditions in the surroundings.

The images from the areas closer to Tromsø demonstrates that the wind speeds were very high and the gusts were even stronger near the spot of the incident.

Meteorological Analysis
The analysis can be deduced from charts.

Skew-T

Conclusions
The severe weather conditions can cause serious incidents of the aircrafts. The flight planning did not consider enough meteorological data and the probable impact of the strong storm at the destination.

Airbus A320 Neo suffered a loss of the engine due to the lightning strike.