United was planning to use the large jets more in March on as it tries to tap into an expected bounce in leisure travel.
Numbers from aviation data firm Cirium show United had scheduled 3,329 flights on wide-body planes in March, up 31% from February. Of those flights, 961 were scheduled on the now suspended 777-200, a 84% jump from their usage in February.
The suspension, which follows an engine failure on a United flight to Honolulu from Denver on Saturday, affects 52 planes. While United has dozens of narrow-body airplanes in storage due to the pandemic, it only has parked 48 wide-body planes with more than 190 seats, and none with as many seats as the 777-200, according to Cirium.
"As we continue working through updating our schedule based on aircraft availability, we will do so with the goal of impacting as few customers as possible," United spokeswoman Leslie Scott said.
Earlier this week United warned its cargo customers of possible disruptions to its flight schedule in March as it juggles its fleet.
Even if flights are impacted by the 777-200 withdrawal, analysts said the ramifications are likely to be far less severe than the grounding of Boeing's 737 MAX jets in 2019, which forced U.S. airlines including United to cancel thousands of flights at a time when the industry was flourishing.
United has options to replace the 777-200, said aviation analyst Robert Mann, though they will vary according to the strength of advanced bookings and the timing of inspections ordered by the Federal Aviation Administration.
Raytheon Technologies owned Pratt is handling the thermal acoustic inspections of the engine's fan blades, which showed signs of metal fatigue in preliminary assessments of the United incident, in a process expected to take around 352 hours of work per plane.
The start date and pace are unclear.
United, Japan Airlines Co Ltd (JAL) and ANA Holdings Inc are the main airlines with the affected planes.
JAL and ANA told Reuters they have replaced the routes that were scheduled on those planes with different aircraft types and do not expect to cancel any flights.
United had the largest total inventory of PW4000-equipped aircraft, according to Cirium, which shows a total 843 aircraft in the airline's fleet, including a total 277 in storage.
While the 777-200s are among United's oldest, it had configured some of them to hold as many as 364 seats, more than any other in its fleet. Using 777s on leisure routes like flights to Hawaii could allow the airline to book more revenue per flight by selling more economy seats on routes that typically do not draw many paid business class travelers.
Amid an overall slump in travel during the pandemic, leisure trips are outperforming business and international travel - namely to beach and mountain destinations.
"That is probably why United would be using these aircraft in the schedule rather than other, newer aircraft," aviation consultant Samuel Engel said.
(Reporting by Tracy Rucinski; Additional reporting by Tim Kelly in Tokyo and Jamie Freed in Sydney; editing by Edward Tobin)
By Tracy Rucinski
