American International Group reported a net loss attributable to AIG of $4.1 billion and an after-tax operating loss of $3.0 billion for the quarter ended September 30, 2011, compared with a net loss of $2.5 billion and an after-tax operating loss of $114 million for the third quarter of 2010.

AIG said the results for the quarter were negatively affected by several macroeconomic drivers, including declining equity markets, widening credit spreads, and declining interest rates. In addition, ILFC, AIG’s aircraft leasing subsidiary, recorded $1.5 billion of impairments related to its older generation and less fuel-efficient aircraft. The leasing unit reported a third quarter operating loss of $1.3 billion, compared to an operating loss of $218 million in the third quarter of 2010.

AIG’s other operations, which now include results from the non-aircraft leasing operations previously included in the Financial Services segment, reported an operating loss of $4.2 billion, compared to an operating loss of $1.1 billion in the third quarter of 2010, reflecting fair value declines of AIG’s holding of AIA Group ordinary shares and its holding of ML III by $2.3 billion and $931 million, respectively, from their values at June 30, 2011.

“AIG continues to navigate a challenging global economic environment, and our results for the quarter were adversely affected by equity market declines, widening credit spreads, and declining interest rates, as well as property catastrophe losses,” said Robert H. Benmosche, AIG president and chief executive officer. “We also took significant impairments at ILFC, reflecting management’s decision on certain aircraft that would be disposed of prior to the end of their previously estimated life in light of technological developments in the aircraft industry, fleet management announcements by certain airlines, and our newly acquired part-out company.”