Pratt & Whitney disagrees with the conclusions drawn relative to engine reliability by the GAO. Our current F135 CTOL engine achieves and exceeds specification requirements (147 percent of required levels). The reliability of the F135 STOVL engine meets 119 percent of its current requirement. The report incorrectly assessed engine reliability, as it did not account for new designs that have been validated and are being incorporated into production and fleet engines. While the report lists some propulsion reliability concerns, the F-35 Joint Program Office and Services have validated our reliability performance and we will continue to enhance reliability for the fleet as it matures to minimize life cycle cost and support continued high rates of engine availability.