Passengers of the Mumbai-bound Rajdhani Express had a narrow escape on Tuesday, when 18 coaches of the train separated from the engine. The engine was kept running alone for one-and-a-half km so that the coaches would not collide with it. Nobody was injured.The 2952 Rajdhani Express departed from New Delhi station at 4.30 pm on Monday. As it neared Billimorya station between Surat and Valsad at 6.36 am, the Centre Buffer Coupler that connects the engine and coaches opened when the train suffered a jolt.“In this situation, the motorman does not have any option but to keep the train running,” said a senior railway official. “Otherwise, the coaches that continue hurtling ahead might collide with it. So it was only after going another kilometre and a half ahead that the motorman stopped the train.”He added, “These are LHB coaches from Germany, which have had other controversies surrounding them when they were purchased for Rajdhanis and Shatabdi Express. There were complaints of technical defects and design problems with the CBC, which might open due to jerks. Several modifications were carried out but such incidents have been continuing due to these couplings.”In another such instance around five years ago, the Centre Buffer Coupler of the Rajdhani Express slipped open near Vadodara but fortunately there was no causalties. This time too, there were no casualties, but officials pointed out that if the route had a slope at that point, there could have been a major accident.Confirming the incident, Western Railway Chief Public Relations Officer (CPRO) Shyam Sunder Gupta said, “It was not dangerous, but it was unusual.”