United Airlines' fleet of 14 Boeing 737 Max aircraft are set to take off again – but without paying passengers.

The Chicago-based airline has received regulatory approval to ferry the otherwise-grounded narrowbodies from Los Angeles and Houston to the Arizona desert, where they will be placed in "short-term storage."

United says it started the relocations today, flying the aircraft to Goodyear airport near Phoenix.

The carrier has three 737 Max jets at Houston's Intercontinental airport, nine at Houston's Hobby airport and two at Los Angeles International airport, it says.

The airline wants to move the aircraft away from Houston due to the threat of hurricanes, which occasionally make landfall along the Texas coast.

Airport construction and space constraints at Los Angeles make that airport a less-than-ideal storage choice, United says.

"Arizona is a much better place to store aircraft due to lack of humidity and other more-favourable weather conditions," says United.

United's flight schedules still have the 737 Max returning to revenue service after 3 November, though exactly when regulators will clear the aircraft to fly remains subject to speculation.

American Airlines' schedules also have the Max returning in November, but Southwest Airlines has been less optimistic, leaving the Max out of its schedules until 6 January.

Boeing has said it hopes to submit a certification-related package to the Federal Aviation Administration in September, starting a review period that experts say could take four to six weeks.

Source: FlightGlobal.com