Wichita ? Union Machinists at Wichita aircraft parts maker Spirit AeroSystems have ratified a 10-year contract by default, as a strike vote fell short of the needed numbers.

Union leaders announced Friday night that 57 percent of the voting members rejected the contract, and 58 percent voted to strike.

But the strike required 66 percent approval, so the contract was accepted automatically.

The contract replaces one that expired at midnight Friday.

The Machinists represent nearly 6,000 workers at Wichita’s biggest private employer. Spirit was formed in 2005 after Boeing spun off its commercial aircraft operations in Wichita and Oklahoma.

Union leaders had endorsed Spirit’s offer, which includes cost-of-living adjustments, a 1 percent wage increase in four of the 10 years, an early retirement option and increases in pensions.

Spirit said the unusual 10-year contract showed its commitment to Wichita.