As millions of Americans prepare for a summer of vacation flights, Ben Wallander beats the books and the simulator.

The 27-year-old is one of hundreds of Delta Air Lines pilots (FROM N) and American Airlines (AAL.O) are rushing to exercise after a surge in travel bookings triggered by COVID-19 vaccinations.

Thousands of pilots at Delta and American at some point in the past year lost their active status, which expires after 90 days without a flight when the coronavirus pandemic slammed the brakes on air traffic and brought airlines to their knees.

A long weekend on US Memorial Day starting Friday is expected to usher in a projected spike in summer recreational travel that will test the airlines’ ability to make a long-awaited comeback.

While airlines have already retrained many of their pilots, the travel resurgence has forced Delta and American to seek more simulators and flight instructors to speed up training and clear a traffic jam.

Both airlines are recipients of three COVID-19 aid packages valued at $ 54 billion, mostly in the form of free cash.

Analysts warn that failure to ensure a smooth travel recovery could result in flight cancellations and delays in generating the cash needed to repay pandemic debt.

“It’s quite a puzzle,” said McKinsey aviation advisor Vik Krishnan about the logistics of pilot training, comparing it to a game of Tetris.

Delta and American must train pilots who have flown with fleets that have retired due to the pandemic, as well as those who fill vacancies on various types of aircraft after buying colleagues, in addition to annual recurring training requirements.

“Our pilot training has stayed on track with our planned deployment plans and will continue to do so,” said Delta spokesman Anthony Black.

American spokeswoman Sarah Jantz said: “We have the training capacity ready and are able to handle the expected increase in flying.”

BOOM AND BUST

Before the coronavirus crisis, global air traffic grew at a record 5% per year, requiring 804,000 pilots over the next 20 years, based on Boeing (PROHIBITION) Estimates.

However, volatility in the availability of pilots has plagued the aviation industry, moving from global bottlenecks prior to COVID-19 to unemployment or vacation programs during the pandemic and now renewed concerns about bottlenecks in the major U.S. market.

The problem got worse during the industry’s worst crisis and added further pressure.

Delta has around 12,600 pilots and 1,600 internal captain and first mate positions, as memos show.

Wallander, an Airbus (AIR.PA) The A220 pilot was recalled by Delta in March, but will not be trained until June.

He told Reuters that he had decided to stick with the A220 upon returning to the cockpit as it means he “doesn’t have to go through a long training course”.

Courses can range from days to weeks depending on how long the pilots have been away and whether they are improving their positions or changing aircraft types.

All pilots are required to spend time in simulators, of which airlines have a limited number, followed by flights alongside a training captain who signs off on their return.

However, many of these “check” pilots have to be trained in different types of aircraft after changing fleets or have retired, which leads to knowledge and resource gaps.

“All of this cascades into training,” said Dennis Tajer, spokesman for the Allied Pilots Association, which represents 15,000 pilots at American.

United Airlines (UAL.O), the other major U.S. international airline, has signed a deal with its pilots union that helped nearly 12,000 people maintain active flight status through the pandemic.

Among the efforts to improve training, American is hiring simulators owned by Canada’s CAE (CAE.TO) At its home base in Texas, Delta is conducting more training outside of its Atlanta base and adjusting briefings around simulator time to allow for about 25% more sessions per day.

American plans to fly around 90% of its pre-pandemic domestic flight schedule this summer. Delta is also commencing flights and expects its planes to be 90% full this weekend.

“We hit the brakes very quickly and we’re coming back even faster now,” said Chris Riggins, spokesman for the Air Line Pilots Association at Delta.

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