The American Airlines crash has stoked new fears for the safety of air travel. On the ground the nation's airports are still struggling to improve the quality of the private companies that operate passenger security checkpoints. Some of those firms have been sharply criticized for myriad shortcomings ... including a failure to detect concealed weapons and hiring checkers with criminal records. Globe Aviation Services handles security screening at Minneapolis-St. Paul International Airport. The company says it's ...... done much to tighten procedures since the September 11 attacks. Minnesota Public Radio's Kaomi Goetz reports.