FORT WORTH, TX—Union members at Lockheed Martin’s assembly plant here have voted to ratify a new contract that includes wage hikes and improvements to retirement benefits. The facility produces the F-35 fighter.

Some 5,000 members of the International Association of Machinists and Aerospace Workers District 776 in Fort Worth approved the deal that their negotiating committee had unanimously recommended, according to a statement.

Terms include a 16 percent effective general wage increase over the four years of the contract, cost-of-living adjustments, a $4,000 per person ratification bonus, and a continuation of the union’s health care plan.

“We have once again proven why the IAM is the largest and strongest aerospace and defense labor union in the world,” IAM International President Robert Martinez Jr. said in the statement. “Our members stood strong and demanded a strong contract every step of the way.”

Lockheed did not comment on the contract. Negotiations over the new labor deal began in February. The new contract officially took effect April 25 for four years and two months.