Air Vall‚e flight 233 made a nose gear-up landing at Catania-Fontanarossa Airport (CTA), Italy. The aircraft, a Fokker 50, operated by Amapola Flyg on behalf of Air Vall‚e, departed Rimini at 08:49 on a domestic service to Catania. The aircraft was approaching runway 08 at Catania Airport when the nose landing gear failed to deploy. The approach was abandoned about 10:37 hours. The airplane climbed to 2900 feet and entered a holding pattern to the east of the airport while the crew tried to troubleshoot the problem. Finally a forced landing was carried out on runway 08 at 11:34 with the nose gear doors open but the nose gear retracted. CAUSES The accident was caused by the failure of the nose landing gear (nose gear up) due to over-extension of the shock absorber which caused interference between the tires and the NLG compartment and locked the NLG in a retracted position. The over-extension was caused by the incorrect installation of some internal components of the shock absorber during the replacement of the internal seals the day before the accident. The following factors contributed significantly to the improper activity conducted at maintenance: – the insufficient experience of technical personnel in carrying out the maintenance tasks conducted on the NLG; – the lack of controls on the operations carried out, deemed unnecessary by the CAMO engineering department; – the lack of definition of roles and tasks during the planning phase of the maintenance work; – the operational pressure on maintenance personnel, arising from the need to conclude maintenance operations quickly in order not to penalize the management of the aircraft; – the insufficient clarity and lack of sensitive information in the maintenance tasks and related figures contained in the AMM, regarding the replacement of internal shock absorber seals, subsequently made clearer by the manufacturer; – the reported black and white printing of the applied AMM procedures, which could have made the warnings in the manual barely legible.