NEW DELHI: Like western airlines, Indian carriers will now carry restrainers, like plastic handcuffs, to restrain unruly flyers to ensure they remain bound to their seats till the plane lands safely. Jet Airways official said the Directorate General of Civil Aviation ( DGCA ) has recently allowed airlines to carry restrainers (meaning plastic handcuffs) on board."The DGCA's nod came in end-2015. We will have restrainers on board shortly and use them in the interest of flight safety as and when required," the Jet official said. Airlines indicated they will be using this step when needed to curb the menace of disruptive behaviour that threatens safety of aircraft. SpiceJet official said the airline carries handcuffs on all its aircraft and gives martial arts training to its crew.IndiGo on Wednesday said it has been carrying restraint devices -nylon ropes - on all its flights for some time now. Vistara did not specify whether it carries restrainers but said it takes "adequate measures" for tackling unruly behaviour.An IndiGo statement said: "As per DGCA guidelines, crew members must attempt to defuse a critical situation until it becomes clear that there is no way to resolve through verbal communication and written notice to passenger. Restraining devices should be used when all conciliatory approaches have been exhausted. We, at IndiGo, carry a restraint device on all our domestic flights." Made of nylon, these restrainers are called "tuff and tie or tuff-cut".IndiGo has trained its cabin crew to apply restraining devices when needed. The airline has drawn up a four-level threat scenario (see box) and restrainers can be used when the unruly flyer's behaviour threatens flight safety according to that chart.