The federal agency in charge of aviation security is considering major changes in how it screens airline passengers, including proposals that, an official said, would lift the ban on carrying razor blades and small knives as well as limit pat-down searches. The Transportation Security Administration (TSA) will meet later this month to discuss the plan, which is designed to reduce checkpoint hassles for the nation's 2 million passengers. The agency proposed the changes after its new chief, Edmund S. Hawley, called for a broad review in hopes of making airline screening more passenger-friendly. An initial set of staff recommendations drafted...