Cleaners employed by Mitie at Manchester airport struck for the second time in a month on Friday of last week, against a £90 a month pay cut.
They are members of the Unite union.
They overwhelmingly rejected an insulting offer of a one off payment of £200—with possible further discussions next year—at a mass meeting.
Some supervisors had been threatened with losing their jobs if they struck, but others were on the picket line.
At least one manager called in sick rather than have to clean the airport.
Workers organised rotas to make sure there was picketing all day. Taxi drivers and others blew their horns in support, showing the potential for solidarity if workers escalate their action.