The effect of gas turbine lubricant oil soaking, thermal cycling and their combination on morphology and tension and flexure properties of pultruded composite was studied. Two types of lubricant oils were used: Mil-L-7808 and Mil-L-23699. Composite samples were oil soaked for 720 h and microscopic analysis and mechanical tests were conducted. Samples were thermal cycled for 600 cycles (RT to 315 degrees C) and measured tension and flexure properties. Samples were oil soaked, thermal cycled and then tested. Results of these three groups of environmentally aged samples were compared with non-aged samples. The significance of aging effect is discussed in the article. (C) 2007 Wiley Periodicals, Inc.