Over 1,500 aerospace workers went on strike on Monday over pensions.
The workers at flight systems manufacturer Goodrich Actuation voted to walk out over proposed changes to its pension scheme.
There was picketing at the firm’s sites in Wolverhampton, Birmingham, Merseyside Hemel Hempstead.
Andy Taylor, of the Unite union, said staff were also starting a continuous overtime ban.
He told Socialist Worker that, “Workers are angry the company has closed its final salary scheme to new employees and that it has made changes to members’ contributions and benefits, including raising the contribution rates.
“This is outrageous behaviour from an aerospace company which has a well-funded pension scheme and a £3.5 billion order book.
“The union will not accept any changes to the pension scheme and the workers will make this absolutely clear to the company when they hold a one-day strike.”