The Taiwan Transportation Safety Board (TTSB) released the final report on the Investigation of the Taiya Aeronautical Association WR2711 ultra-light vehicle crashed during landing at the Wuri activity field, Taichung City.

On July 1, 2024, a Taiya Aeronautical Association Savannah S ultra-light vehicle, control number WR2711, took off from the Wuri activity field in Wuri District, Taichung City at 1138L, with 1 operator and 1 occupant. The vehicle crashed into the woods on the north side of runway 13 at 1154L during landing. The vehicle suffered substantial damage and the occupant was seriously injured.

According to the Transportation Occurrence Investigation Act, and the content of Annex 13 to the Convention on International Civil Aviation, the Taiwan Transportation Safety Board (TTSB), an independent transportation occurrence investigation agency, was responsible for conducting the investigation. The investigation team is composed of members from Civil Aeronautics Administration (CAA) and Taiya Aeronautical Association. The final investigation report was reviewed and approved during the 73rd TTSB Board Committee Meeting on March 14, 2025.

The investigation report identified a total of 6 findings and proposed 3 recommendations to enhance transportation safety.

The finding related to probable causes is as follow:

1. Taiya's management of the trees near the Wuri activity field, which affect the runway transitional and the approach surfaces, was insufficient. As a result, the trees intruded into the area that needed to be cleared. At the time of the occurrence, there may have been a zone with noticeable wind direction and speed changes above the field, causing the vehicle to roll left and deviate from its flight path. The left wing struck trees higher than the approach area, leading to the crash.

The 3 findings related to risks are as follows:

1. The operator of the occurrence had an expired operator license but still engaged in flight activities. The runway length applied for by Taiya was insufficient, the fixed obstacles did not meet the clearance requirements, the activity site was poorly managed, and actions such as not reporting the occurrence and moving or dismantling the wreckage by themselves show that Taiya needs to improve its compliance with regulations.
2. The Wuri activity field has obstacles that are higher than the runway approach and transitional surfaces, which do not meet the flight safety standards required for ultra-light vehicle management regulations.
3. The Civil Aviation Administration should fully consider the practical operational conditions when reviewing and inspecting Taiya's activity field to maintain flight safety.

The 2 other findings are as follows:

1. The weight and balance of the occurrence vehicle were within the limits, and there were no abnormalities in the airworthiness information before the flight. The engine was operating normally before the occurrence.
2. Taiya maintained a runway length of over 240 meters at the Wuri activity field, but the length applied for did not meet the requirements in the pilot operating handbook for the occurrence vehicle.

The 3 Transportation Safety Recommendations are as follows:

To Taiya Aeronautical Association

1. Strictly comply with all regulations, standard procedures and the association's activity guidebook when conducting ultra-light vehicle activities.

To Civil Aeronautics Administration

1. Examine the review and inspection mechanisms related to ultra-light vehicle activities to improve the management of ultra-light vehicles.
2. Supervise and ensure that Taiya Aeronautical Association strictly complies with all regulations, procedures, and manuals when conducting ultra-light vehicle activities.

Full Final Report in Chinese is available for download at https://www.ttsb.gov.tw

Ya-Ting Chang, Secretariat Office

Tel: +886-2-7727-6210

E-mail: yating@ttsb.gov.tw

Kuo-Chih Chang, Aviation Occurrence Investigation Division

Tel: +886-2-7727-6310

E-mail: kcchang@ttsb.gov.tw