Boeing has reversed its stance that 737 MAX pilots need only computer-based training before the jet returns to service and is now endorsing the use of simulators. The change announced on Tuesday is in line with the thinking of several non-US regulators and is likely to be regarded as a plus in the global recertification process. But it could also delay the plane’s return to service and add significant costs as airlines accommodate the extra training requirements to cover changes to the aircraft’s flight control software prompted by two fatal crashes. The US Federal Aviation Administration will make a final decision on the training requirements and the regulator says it is considering the Boeing recommendation. READ: American staff gain $US30 million from 737 MAX deal. It still remains unclear when the MAX, which has been grounded worldwide since March as Boeing attempts to satisfy the FAA it is safe to fly again, will be recertified The company said in a statement that it was now recommending both simulator and computer-based training due to its “unstinting commitment to the safe return of service as well as changes to the airplane and test results”. "Public, customer and stakeholder confidence in the 737 MAX is critically important to us and with that focus Boeing has decided to recommend MAX simulator training combined with computer-based training for all pilots prior to returning the MAX safely to service,” interim Boeing chief executive Greg Smith said. The ease with which pilots could move between the Boeing NG and the MAX was a major selling point for Boeing and the manufacturer initially stuck with its view that computer-based training using a laptop was sufficient. A draft report by the MAX Flight Standardization Board last year also stopped short of recommending simulator training, prompting criticism from overseas authorities such as those in Canada. The Boeing turnaround reportedly comes after a recent flight analysis of the new MAX software showed pilots were not using the correct procedures to handle emergencies. Some pilots had been required to undertake simulator training when switching to the MAX even before the Ethiopian Airlines tragedy that prompted the global MAX fleet to be grounded in March.