In a secret internal briefing entitled "Mile Stones" and marked "Confidential", BA's caterer Gate Gourmet declared "Recruit, train and security check drivers. Announce intention to trade union, provoking unofficial industrial action from staff. Dismiss current workforce. Replace with new staff."

The shocking move was part of a 15-week timetable, first mooted a year ago, to provoke workers into striking so they could be replaced with cheap East European labour trained at secret bases. A steering committee cited the top risk as "potential for wider Heathrow based disruption".

But if the risks were high, so were the rewards. The dossier forecast the £2.5 million sacking plan would save up to £6.5 million a year. An industry expert estimated there could be annual pension savings of up to £7 million.

An insider claimed that action like that detailed in the leaked documents culminated in last week's crippling protests at Heathrow. Gate Gourmet sacked 670 workers following an unofficial stoppage over the employment of 130 casual staff. The move led to wildcat strikes by1,000 other airport workers which stranded up to 100,000 BA passengers, some of them for several days.

An insider said: "This is all about pure greed. They deliberately made the workers lives absolute hell, then told them they were outsourcing their posts to spark a reaction. It's a shocking way to treat people."

TGWU shop steward, Sarijit Singh Sandu, declared: "We've always believed the actions were pre-planned. Now we are in no doubt."

The sacking plan was drawn up by a tight-knit team of hard-line businessmen from Gate Gourmet's US owners, the Texas Pacific Group. Once a month directors came over from America for updates. Towards the end they came every week. The timetable of action kicked in as soon as Gate Gourmet lost a Virgin contract a few months ago.

An insider source said a solicitor was consulted. The source said: "He said if staff could be provoked into unofficial action they could all be sacked and have no legal redress. It would also mean the company could seek damages from individuals."

Referring to the firm's drivers, the dossier details how staff could be told their working conditions were going to be dramatically worsened, so provoking fury. Among the threats listed were "No redundancy packages, no leaving early, no extra pay for extra work, random drug testing, no smoking, eating or drinking in cabs."

The plan also advises how to sack staff. It reads: "Immediate dismissal without legal protection. Collect ID cards, airside passes, locker keys. HR to issue dismissal letters, extra security presence. Security to escort dismissed staff from the premises."