(Reuters) - Canadian airlines are making preparations for the day when Boeing's BA.N grounded 737 MAX jet can fly again, but one executive said work must be done to regain travelers' trust in the U.S.-made narrowbody involved in two deadly crashes.

An Air Canada Boeing 737 MAX 8 aircraft is being towed in as another Air Canada Boeing 737 MAX 8 aircraft is seen on the ground at Toronto Pearson International Airport in Toronto, Ontario, Canada, March 13, 2019. REUTERS/Chris Helgren

WestJet Airlines WJA.TO Chief Executive Officer Ed Sims told Reuters on Tuesday that over 50% of people questioned by the carrier have expressed reluctance, or a lack of confidence to fly on the MAX.

“There is a very major job to be done...to remind our guests of the previous safe track record and to give people confidence that the changes that have been made will make this the safest narrowbody domestic aircraft that has ever flown,” he said in an interview.

The 737 MAX has been grounded worldwide since mid-March while Boeing BA.N updates flight control software at the center of two crashes in Indonesia and Ethiopia that together killed 346 people within a span of five months.

North American carriers, including WestJet and rival Air Canada AC.TO, are taking steps to prepare for the plane's ungrounding, even as they scramble to meet demand with slimmer fleets.

Air Canada, the country's biggest carrier, has pulled the MAX from its schedule until Feb. 14, 2020. Calgary-based WestJet, which has agreed to a C$3.5 billion ($2.68 billion) takeover by an Onex CorpONEX.TO-led consortium, has taken the MAX out until Jan. 4, but is reviewing whether to extend that into February.

Sims added he would fly on a planned MAX demonstration flight with media and would “happily” bring his family when the aircraft again takes to the skies.

Air Canada Chief Executive Officer Calin Rovinescu told analysts on an earnings call that the carrier would await the U.S. Federal Aviation Administration’s decision to clear the aircraft before taking steps to hire pilots for its MAX fleet expansion.

“We’re looking at potentially hiring up to 350 incremental pilots next year,” he said.

Air Canada, which now has 400 MAX pilots and 24 grounded MAX jets, had initially expected to operate 50 of the narrowbodies by mid-2020.

Boeing Chief Executive Officer Dennis Muilenburg on Tuesday started a two-day testimony before U.S. lawmakers in Washington, where he acknowledged that the planemaker made errors.

Air Canada has forecast capacity growth of 3% during the fourth quarter, following a 2% dip during the third quarter. Air Canada shares traded up 3.54% midday after carrier executives said the grounding has not derailed several key targets and raised the prospect of future share buybacks.

“Looking ahead to the fourth quarter, we anticipate year over year traffic and revenue growth despite the MAX grounding,” Air Canada chief commercial officer Lucie Guillemette added.