BENGALURU: The HTT 40 basic trainer aircraft -- began the most awaited phase of the `spin test’ by successfully entering in to two turn spin and subsequently recovering with the appropriate controls. Two test pilots undertook the first ever spin entry testing today around 1.30 pm. The aircraft was piloted by Gp Capt (Retd) KK Venugopal, DGM-Test Pilot (FW) from front cock pit and Gp Capt S Chaki (Retd), Sr. Test Pilot (FW) from rear. The stall testing was already completed and the project galloped its way to spin tests, the HAL said in a media release.HAL Chairman R. Madhavan said that the successful start of the spin testing gives a boost to HAL and also restores credibility of HAL in successfully designing a spin worthy aircraft.The spin testing is the most crucial and challenging aspect of flight testing of any aircraft development programme. HAL’s Aircraft Research and Design Centre (ARDC) had conducted extensive wind tunnel testing and mathematical model analyses to arrive at the spin chacteristics of the aircraft. The entire study is put to test during those first few moments of spin testing, he saidAccording Mr. Arup Chatterjee, Director (Engg and R&D) the PSQR test points have been met and the spin completion is the last metric which needs to be accomplished before the aircraft enters service. As a matter of fact, HTT 40 exceeds the Preliminary Services Qualitative Requirements (PSQR) on most fronts and offers a technologically advanced product than its competitor.The project started its detail design in August 2013 with internal funding and quickly made its way to the spin tests in matter of five years. The Defence Acquisition Council (DAC) has approved procurement of 70 Basic Trainer Aircraft from HAL.