A Boeing 737-8 (G-CRUX) operating a scheduled passenger flight from London Luton to Athens was involved in a serious incident on 22 April 2025 when the crew departed using incorrect take-off performance data after changing from a full-length runway departure to an intersection departure from Taxiway A.
The crew had originally calculated performance using the full 2,116 m runway length, which required a thrust setting of 81.4%. When they accepted the shorter intersection departure, the available take-off run reduced to 1,771 m and the required thrust increased to 85.2%. However, the flight management system was not correctly updated and the aircraft used only 82.1% thrust during the take-off.
As a result, the aircraft accelerated more slowly than intended and became airborne with less than 162 metres of paved runway remaining. It crossed the runway threshold at a height of only 13 ft above ground level and climbed significantly more slowly than expected. Air traffic controllers observed the unusually shallow climb profile on radar and CCTV.
Photo source: Jonathan Payne from Ayr, United Kingdom, CC BY-SA 2.0 <https://creativecommons.org/licenses/by-sa/2.0>, via Wikimedia Commons