Citing industry objections, the Transportation Security Administration is preparing to scale back a plan to expand aviation security rules for the first time to thousands of private planes.

TSA officials said this week they expect to issue a revised plan this fall that will significantly reduce from 15,000 the number of U.S.-registered general-aviation aircraft subjected to tougher rules.

Also, instead of mandating that all passengers aboard private planes be checked against terrorist watch lists, name checks in many cases could be left to the discretion of pilots, they said.

The shifts would mark significant rollbacks of security changes that supporters called overdue and essential to preventing terrorists from using small planes to smuggle dangerous weapons or carry out suicide attacks. Opponents, however, called the measures unwarranted, poorly thought out and overly burdensome on aircraft owners and manufacturers.

"With the current threat environment ... I find it rather shocking that they would retreat," said consultant Glen Winn, former United and Continental airlines security chief. "I would hope there's a review in process before this is put in motion."

A May 2009 report by the Department of Homeland Security inspector general, however, said security threats involving general- aviation plans are "limited and mostly hypothetical."