(FORTUNE Magazine) – The Pension Benefit Guaranty Corp. (PBGC) rang in the new year by announcing that it would take over responsibility for the pilots' pension plan at United Airlines, to the tune of $1.4 billion. The federal agency, which acts as an insurer for corporate pension plans, has spent much of the past few years securing pension plans for Big Steel, and it looks as if airlines are next. The PBGC became the trustee of US Airways' pilot pensions in 2003 and may announce a takeover of that struggling carrier's other three pension plans within the month. The grand total at US Air? It's $2.8 billion, chump change next to the $6.4 billion the PBGC will pony up if it has to bail out all four of United's plans. To date the airline industry, which makes up 2% of participants in the program, has made 20% of claims. Here, how a $6.4 billion bailout would compare with the PBGC's biggest payouts to date. -- Kate Bonamici