WASHINGTON – Amid fierce opposition from charter and cargo airlines, as well as alarms raised by Pentagon officials, the Obama administration has delayed new safety rules aimed at preventing airline pilots from becoming so exhausted that they make dangerous mistakes.

Charter airlines — also called nonscheduled airlines — not only fly tourists and sports teams, they provide the planes and pilots for thousands of military flights every year. Civilian airlines transport more than 90 percent of U.S. troops and 40 percent of military cargo around the globe under contracts with the Pentagon. The trips are frequently long, usually at night and often to danger spots like Afghanistan.

The rules the Federal Aviation Administration proposed last year are designed to address long-standing concerns that pilot fatigue contributes to errors that cause accidents. They would reshape decades-old regulations governing how many hours a pilot can be on duty or at the controls of a plane, to take into account the latest scientific understanding of how fatigue slows human reflexes and erodes judgment.

Administration officials declined to comment on the reasons for the delay. A new schedule for issuing final rules indicates the target date — which has been repeatedly pushed back — is now in late November.

The nation’s top aviation accident investigator blamed the delay on the influence of airlines that put profit ahead of safety.

“There are special interests who are holding this rule up because it’s not in their financial self-interest,” National Transportation Safety Board Chairman Deborah Hersman said. “The American people expect safety to trump special interests, not the other way around.”

The proposed rules would allow some pilots to fly more hours — 10 instead of the current maximum of eight — if they begin their day in the morning so that most of their flying takes place during the daytime. But pilots who fly overnight would be allowed fewer than eight hours because people naturally crave sleep during those hours.