| New
            Delhi, 15 May 2002
            
            
            
               In
            the last decade the IAF has been bugged with a plethora of air
            accidents and the figure of 239 crashes has been floated in the
            media and out of these the major casualty has been the MiG 21
            series. Over 100 MiG 21 aicraft have gone down and have taken over
            38 lives  the lives of pilots trained at great cost and of
            great value to the nation. 
 There
            have been many reasons for the accidents. The landing speed of the
            MiG 21 is the highest in the world and at 320 knots it is fatal if
            the pilot makes the slightest mistake while landing. The former
            Chief of Air Staff ACM A Y Tippnis went for a sortie and had to
            abort his first landing and there was panic in the control tower.
            Being a MiG veteran though, he landed the aircraft safely.
            
             The
            MiG 21 aircraft design is old and the earlier versions  MiG 21
            Type 75 is a truly obsolete machine and only skilled operators can
            cope with an emergency on this machine. 
            
             The
            engines of the earlier MiG 21s are the R-11, which are of 1960's
            vintage. Since then however, the engine and compressor systems have
            progressed immensely. Today the MiGs are powered by the HAL Koraput
            manufactured R25 engines.
            
             When
            there is a flame out i.e. engine failure  due to a fuel line
            problem or drop in pump pressure or such other problem that the
            pilot begins to loose height very fast and in the panic of
            restarting the engine, it can happen that the compressor gets an
            uneven fuel-air mixture, leading to a small explosion or over
            exertion on the compressor blades. 
            
             Combined
            with this problem has been the inadequate training of pilots to
            transit from the Iskara and IJT trainers to the fast supersonic MiG
            21. Therefore, reports by ACM La Fontaine and Dr. A. P. J. Abdul
            Kalam in the past had cited pilot error, mechanical failure and bird
            hits as the problem areas and the Air Force has not been able to
            lick them. It is good that ACM S. Krishnaswamy has grounded the Type
            75, which may even have to be phased out.  
 More
            recently the media had cast doubts over the efficacy of the R25
            engine manufactured by HALs Koraput Division, which powers the
            MiG 21 BIS multi-role fighter aircraft. The engine is a twin spool,
            axial flow, turbojet engine incorporating an after-burner system and
            variable area jet nozzle. The engine has provision for an emergency
            after burner thrust boost, which can be selected below 4.5 km
            altitude. The media reports suggested that substandard spares were
            used to overhaul the engines, which resulted in their failure. Back
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