The corporation, which is funded by insurance premiums paid by pension funds, regularly operates at a deficit, including a record deficit of $33.5 billion in May.
Last November, acting PBGC director Vincent K. Snowbarger conceded that the corporation needed help.
"We won't fail to meet our obligations to retirees, but ultimately we will need a long-term solution to stabilize the pension insurance program," he said in a statement.
Montgomery argued that the PBGC's problems will only get worse as the stock market fails to deliver the kinds of returns pension funds had been counting on, meaning they'll be more likely to rely on PBGC insurance.
"They're going to have trouble making payments and having enough money to meet their obligations" by either 2010 or 2011, Montgomery told ABCNews.com. "The federal government is going to have bail them out."