By Allison Lampert

MONTREAL WestJet Airlines pilots will get a 24% hourly raise over four years, plus other pay and benefits as part of a tentative agreement reached in May, according to a copy seen by Reuters on Friday.

The tentative agreement was reached by Onex Corp's WestJet and the Air Line Pilots Association (ALPA) less than 24 hours before the start of an expected strike at Canada's second-largest carrier.

The deal, pending approval by WestJet pilots, is expected to put pressure on Air Canada as the larger rival faces a call from its pilots to narrow the earnings gap with higher-paid aviators in the United States.

North American pilots are pressing for higher salaries and better scheduling after U.S. aviators made big gains in a recent deal with Delta Air Lines that delivers a 34% pay increase over four years.

Besides the 24% raise, the WestJet deal also provides back pay to Jan. 1, along with additional benefits and restructuring of retirement funds, according to an executive summary, which was reported earlier by the Canadian Press.

Air Canada's estimated 4,500 pilots who joined ALPA this month, must decide by Monday whether to stay within the framework of a 10-year agreement reached in 2014, or use a type of escape clause to enter into full negotiations this year.

Air Canada, which is not currently in negotiations, has said it abides by the 10-year contract.

After 11 years, a top-paid Air Canada B787 pilot earns C$313.81 ($234.68) an hour, according to an internal table seen by Reuters. According to WestJet's deal, a comparable B787 pilot would earn C$319.25 as of July 2023, with pay increasing to C$347.16 by 2026.

The deal would also fully integrate the flight operations of WestJet's budget carrier Swoop into its mainline by October 2024.

($1 = 1.3372 Canadian dollars)

(Reporting By Allison Lampert in Montreal; Editing by David Gregorio)