U.S. Sen. Charles Schumer is urging federal authorities to study whether U.S. passenger jets should be equipped with devices that would protect them against missiles like those that recently shot down a Malaysian Airlines flight over Ukraine and projectiles fired near Tel Aviv airport in Israel.

The New York Democrat is calling for a comprehensive interagency study by the Department of Homeland Security, Defense Department and Federal Aviation Administration.

He notes a federal study on the technology was done in 2004, but no action was taken.

According to Schumer, a Government Accountability Office suggests more than 500,000 portable surface-to-air missiles in existence worldwide, with a substantial number acquired by terrorists.

Portable missiles packaged in tube, the launching mechanism and battery can fit in a car trunk.

(AP)