John Plueger has become the second chief executive of AIG’s airplane leasing arm to step down in the last two months. His departure triggered speculation that he would join the founder of the business, Steven Udvar-Hazy, in setting up a new aircraft leasing venture.

AIG said International Lease Finance (ILFC) will be run by chief financial officer Alan Lund until a permanent replacement is found.

Plueger, 55, was named acting chief executive in early February when Udvar-Hazy stepped down from the top job.

Udvar-Hazy has been planning to buy back parts of ILFC for some time, and is thought to have won backing from private-equity groups to acquire up to $4.5bn of the portfolio last October. The lessor has about 1,000 aircraft in its fleet valued at more than $44bn.

“The implication would seem to be that Hazy is starting a venture and Plueger will be joining him,” Richard Aboulafia, vice president of US consulting firm Teal Group, told Bloomberg.

Udvar-Hazy built ILFC into the world’s biggest plane leasing company and sold it to AIG in 1990. Plueger helped lead the company for more than two decades and had been president and chief operating officer since 1995.

AIG president and chief executive Robert H. Benmosche said the company expects “a smooth transition” as it searches for a permanent CEO for the aircraft leasing divison. “ILFC and AIG are confident in the long-term potential of ILFC as a leader in its marketplace,” he added.

ILFC hasn’t had access to the usual funding options since 2008 when its parent company nearly collapsed and had to be bailed out by the US government. But the aircraft leasing business managed to sell $2bn of debt earlier this month, and also secured $1.3bn in term loans.

AIG initially planned to sell ILFC as part of an effort to repay taxpayers for its $182bn bailout.

Douglas Steenland, an AIG board member and the former chief executive of Northwest Airlines, replaced Udvar-Hazy as chairman of ILFC in December.

Lund, who has served as finance chief for the last 28 years, is replaced in this role by the company’s senior vice president of finance, Fred Cromer, who joined ILFC in July 2008.