Boeing has found a way to fix battery problems with its grounded 787 Dreamliner jets which involves increasing the space between cells, a source familiar with the US company's plans said.
"The gaps between cells will be bigger. I think that's why there was overheating," said the source, who declined to be identified because the plans are private.
The 50 787s in commercial service were grounded worldwide last month after a series of battery-related incidents including a fire on board a parked plane in the United States and an in-flight problem on another jet in Japan.
The logical solution for Boeing would be to install ceramic plates between each cell and add a vent to the battery box, Kiyoshi Kanamura, a professor at Tokyo Metropolitan University who has conducted research with several Japanese battery makers, told reporters on Tuesday.
Earlier on Wednesday, the chairman of state-run Air India said Boeing is hopeful of getting the 787 back in service by early April.
"They said that these planes should start flying again from early April. They can't be sure but they are hopeful," Rohit Nandan said.
Air India has six Dreamliners and has ordered 21 more. The question of the airline seeking compensation from Boeing for the jet's problems would be taken up once the aircraft are flying again, Nandan said.
"Good progress is being made", a Boeing spokesman in Seattle said in response to questions about a possible flight restart in April.
"We have been in close communication with our customers since this issue arose. The details of our conversations with customers are confidential," he added.
Spokesmen for Japan's All Nippon Airways, which has the biggest fleet of 787s, and Japan Airlines said they were unaware of the suggested April schedule.