The retired pilot who safely landed a passenger jet in the Hudson River in 2009 after a crippling bird strike to the aircraft says there's another potentially worse danger lurking in the skies: recreational drones. 

Capt. Chesley "Sully" Sullenberger, who now works as an aviation safety expert, tells Fortune magazine in a story published Monday that he wants to see improved regulation of the recreational drone industry. 

But he said regulation needed to be done right and with some sense of urgency. "How do we balance between undue delay and forcing people who fly to accept risk that they shouldn't have to accept?" 

The Federal Aviation Administration reported last week that pilot sightings of drones had more than doubled between the beginning of the year and Aug. 9 compared to last year. There were more than 650 reports compared to 238 in all of 2014. 

Aviation experts and policymakers are increasingly concerned that a collision between a passenger jet and a recreational drone is increasingly likely as unmanned aircraft proliferate in the skies. The results of such a collision could be devastating.  

In an interview with "Face the Nation" on Aug. 2, 2015, he speculated what that might look like given that an eight-pound bird can bring down an airplane. "Imagine what a device containing hard parts like batteries and motors can do that might weigh 25 or possibly up to 55 pounds to bring down an airplane -- it is not a matter of if it will happen," he said. "It is a matter of when it will happen."