The Verification of the Technical Conditions of a Combat-Trainer Jet’s Airframe

The combat-trainer jet aircraft is an important element in the process of fighter pilot training. This type of aircraft provides a means of transition from basic training on low-speed propeller trainers to piloting high-speed and highly maneuverable fighter aircraft. Nowadays, in Poland, the PZL TS-11 “ISKRA” jet trainers, designed in 1960s, are employed for training purposes. Because of financial considerations this trainer hasn’t been yet replaced by modern aircraft that conforms to current specifications and needs. As is the case with other aircraft in service of the PLAF, the TS-11 fleet has a large reserve of remaining Hourly Service Life (HSL). This opens an opportunity to extend the Calendar Service Life (CSL), so as it matches the HSL. To this end, a series of technical and research activities needed to be undertaken. The Air Force Institute of Technology is conducting the necessary verification of airframe structural conditions in cooperation with the Military Aviation Works No. 1 J.S.C. (branch in Dęblin) responsible for the overhaul and repair operations. The AFIT’s activities in this program include:
• deformation analysis of the selected surface areas of the wing and the fuselage;
• assessment of hidden corrosion in riveted joints;
• non-destructive testing of selected riveted joints.
This paper describes the deformation analysis. As of today, the first stage of the deformation inspection has been completed. At this stage, baseline surface measurements were obtained. Further inspections shall be performed cyclically. The future measurements will be used to establish the areas that deform due to the aircraft operation.