Controlled flight into terrain or similar near misses (CFIT/near-CFIT)

N.B: For up-to-date information on CFIT/near-CFIT events, change language selection to Finnish. 

Controlled flight into terrain or similar near misses (CFIT/near-CFIT) 2023

The number of cases in manned aviation was approximately half of the average of 2013-2022. 
However, CFIT cases often have serious consequences; this was also true last year, when two of the cases of the year were classified as accidents and one as a serious incident. One of the accidents led to a fatality, when a general aviation aircraft carrying out an aerobatic show in Selänpää crashed down, killing the pilot. So far, it has been estimated that it was a CFIT case. The cause will be updated after the investigation  (External link)into the case is complete, if it is discovered that it involved a LOC-I, for instance.

In the other CFIT accident, a combination of a towing aircraft and a glider encountered a downburst and heavy downpour that occurred rapidly in the area in Nummela at a low altitude after takeoff. The towing combination was unable to maintain the altitude, and the towing aircraft had to disconnect the glider being towed. The glider carried out an emergency landing in to a forest soon after being disconnected. The glider was seriously damaged and the flight instructor and student pilot in the aircraft were injured.

In the serious incident, a helicopter had to take evasive action in order to prevent hitting a mast. The mast had the required aircraft warning lights, but they may have been covered with frost to the extent that their visibility was less than optimal. The currently used LED lights generate less heat than the previously used types of light.

The number of CFIT cases in drone operations remained at the level of the average for recent years. Typically, they involved a drone colliding with an obstacle, such as a tree or building, leading to the drone being damaged. No people were injured in these cases. 

Types of incidents that contribute to CFIT situations

Situations to be monitored that may contribute to CFIT situations include a wrong altimeter pressure setting, insufficient information on obstacles and errors and deficiencies in aeronautical charts. Furthermore, reports of warnings from the aircraft ground proximity warning system (GPWS) are monitored.

Of these types of cases, the numbers of reports about lack of information on obstacles and deficiencies in map data were above the average of the previous years.

The number of reports about lack of information on obstacles was significantly higher than the average of the previous years. 
During the year, topics included reports of e.g. unauthorised cranes in the vicinity of airports as well as reports of deficiencies in aircraft warning lights e.g. on masts and in wind power plants. A serious incident that occurred in helicopter operations was also related to the visibility of aircraft warning lights. Traficom’s website (External link) provides more information on flight obstacles and applying for related permits.
On 1 October 2023, the responsibility for maintaining the registers of flight obstacles and requests for statements regarding flight obstacles was transferred to Traficom. Several reports were submitted at the end of the year related to the adoption of this new process; in fact, this raised the total number above the average.

Slightly more reports than average were received on deficiencies in map data in either published aeronautical charts or the map databases of aircraft. In a typical case, it was noted that information was missing from an approach chart or there was a mistake in a map in the map database of the aircraft. The cases had no serious consequences.

Reports on wrong altimeter pressure settings were at the level of the average. This means that no significant changes were found in the numbers in Finland, but the issue has been identified as a rising risk factor on the European level. On 9 March 2023, EASA published a bulletin (External link) on the topic; it explained the risks of a wrong altimeter pressure setting and gave recommendations to reduce the risk. 

A wrong pressure setting can result in being above or below the clearance altitude, which in turn is a contributing factor to mid-air near misses. During an approach, a wrong pressure setting may lead to the approach being carried out either at a too high or too low altitude. A too low approach may lead to a CFIT situation.