In a major setback to indigenous development project, the Arjun tank has failed to clear a crucial round of winter trials that were to decide whether the tank will be cleared for bulk production by the Army. While the tank has been consistently suffering transmission problems and trouble in its suspension unit, the latest round of user trials that concluded in March brought out major problems with German engines fitted on the indigenous tank. Now, a disappointed Army Chief has written to Defence Minister A K Antony saying a “lot of improvements” are needed before the tank can be cleared for bulk intake into its armoured regiments. During the five months of Accelerated Usage-cum-Reliability Trials (AUCRT) in Rajasthan, two Arjun tanks that were tested by the Army suffered engine failures on four separate occasions. This, when the Main Battle Tanks had been put through only 1,000 km of trials. The tank is fitted with German MTU 838 Ka 501 engines.While this has come as a major embarrassment for DRDO that has been claiming that all defects on the tank have been rectified, the Army has made it clear that given the present problems on the tank, bulk intake is not an option. The Army has already ordered 124 tanks but had kept its options open for further purchases. “The tanks have performed very poorly. There have been four engine failures so far. The tanks have done about 1,000 km each. There is a problem,” a senior Army officer informed the Parliament Standing Committee on Defence last month. The tanks are now set for an even more gruelling round of summer trials in Rajasthan next month where they will be tested in temperatures of over 40 degrees Celsius.