US corporate travellers will be reluctant to board the Boeing 737 MAX when the grounded aircraft returns to service, a survey has found.

The poll by the Global Business Travel Association (GBTA) found eight out of 10 travel managers are “concerned” about flying on a 737 MAX and four out of 10 “very concerned”.

Two-thirds of travel managers (67%) said corporate travellers would change their travel plans to avoid a Boeing 737 MAX flight, with one in five (19%) “very likely” to change plans.

Six out of 10 said company employees had expressed “concern” about flying on the aircraft, with 19% expressing “a lot of concern”.

The Boeing 737 MAX was grounded in March following the crash of an Ethiopian Airlines flight soon after take-off from Addis Ababa. It was the second disaster involving the aircraft – a Lion Air Boeing 737 MAX crashed after take-off from Jakarta last October.

Boeing announced the completion of a software update of the aircraft’s Maneuvering Characteristics Augmentation System (MCAS), which it believes will address the problem on the 737 MAX, in May.

But the aircraft remains grounded pending agreement among US and global safety regulators on its return and the training requirements for pilots.

The chief executive of Ethiopian Airlines said the pilots of crashed plane were not at fault.

Responding to claims from a US congressman that mistakes by the pilots were a factor in the aircraft’s failure, Tewolde GebreMariam told the BBC criticisms of the crew’s actions were “seriously misinformed”.

The grounding has caused a significant number of flight cancellations in the US where American Airlines, Southwest Airlines and United Airlines are among the biggest operators of the 737 MAX.

GBTA’s poll of US corporate travel buyers found barely one in 10 (12%) reported no concerns among employees about flying on the aircraft.

Six out of 10 (59%) of travel managers said they would be concerned about their corporate travellers’ safety on the 737 MAX and one in five (21%) were concerned about their employees’ safety fears.

One in 10 (11%) expressed concern about their liability for employees on the aircraft.

Only one in six (16%) thought travellers would be unlikely to change plans to avoid the 737 MAX.

GBTA noted also confidence among corporate travellers that the aircraft’s safety problems have been fixed was “mixed”.

One in three respondents (32%) were not very or not at all confident and another one in three (30%) were unsure.

GBTA polled its US travel buyer members on June 7-11 and received 155 responses.

The association claims its members manage more than $345-billion worth of business travel globally.

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