Smugglers facing strengthened border defenses have turned to an old and risky tactic — using single-seat ultralight aircraft to fly marijuana loads into the country.
Officials know of at least three such attempts in recent months — all of which ended badly for the smugglers — but they don't know how many others have been made or whether any have been successful.
The incidents are worrisome to federal officials. They believe more such attempts are happening or will be, though there's no agreement on whether use of the small aluminum tubing aircraft represents a trend or a novelty.
"If the cartels feel they're successful, they'll go with it," said Rick Crocker, deputy special agent in charge with Immigration and Customs Enforcement in Tucson. "If we can shut it down, they'll go with other means."
The recent flights all came late at night at different points along the Arizona-Mexico border, the busiest region for smugglers.
One pilot was tracked and caught in October near Marana, just northwest of Tucson. Another crashed and died in November in a lettuce field north of the border community of San Luis in southwestern Arizona. The third pilot slammed into power lines southwest of Tucson in December and was paralyzed.
In each case the ultralights were loaded down with marijuana, upward of 200 pounds in one instance.
U.S. Border Patrol officials said airborne loads of 150 or 200 pounds aren't necessarily efficient but they show smugglers are trying different things out of necessity and frustration.
Border Patrol agents seized more than 800,000 pounds of pot in Arizona during the 2008 fiscal year. That represented a downward trend from the previous year, suggesting fewer drugs are being brought in.
The flights are only the latest move in a perpetual cat-and-mouse game between smugglers and U.S. agents. Officials say Border Patrol progress in fortifying the border with more agents, fencing and technology has spurred smugglers to rethink strategies.
Now, short-distance air hops and smuggling tunnels are supplementing primary smuggling methods such as using backpackers and pickup trucks to bring loads through remote areas, or driving vehicles with hidden stashes through official border crossings.
The use of ultralights is a reincarnation of similar efforts in the late 1980s and early 1990s, said Juan Munoz-Torres, a spokesman for U.S. Customs and Border Protection's air and marine program.
"History is repeating itself," he said.
Munoz-Torres said ultralights were common before traffickers switched to larger aircraft to ferry contraband between clandestine and often crude border runways.
The airplane flights flourished until the mid-1990s, when six blimp-like radar-equipped balloons called Aerostats were tethered along the U.S.-Mexican border. Their effectiveness in detecting drug-smuggling aircraft squelched those operations.
Munoz-Torres said the air and marine program is using existing technology and acquiring new systems to go after recent illicit ultralight activity.
Officials and experts generally agree that ultralights are harder to detect.
Typically, an ultralight's aluminum framing, triangular-shaped dacron wings and open-truss fuselage give off a scant radar signature, especially when flying at treetop-level, said Joe Clark, an assistant professor of aeronautics at Embry-Riddle Aeronautical University in Daytona Beach, Fla.
They're also relatively cheap for smugglers. A used ultralight can cost around $5,000; a new model easily double that. They're sometimes sold as kits.
Under Federal Aviation Administration regulations, ultralights should only have a pilot's seat, weigh under 254 pounds, carry just five gallons of fuel and fly at a top speed of 63 mph. They're not supposed to carry anything other than a pilot.
No pilot's license or airworthiness certificate is needed.
Regulations say the aircraft shouldn't be flown over populated areas or in the dark.
But drug smugglers aren't known for playing by the rules, and they clearly have adapted by modifying their aircraft. The ultralight that crashed near San Luis was carrying 141 pounds of pot strapped into a specially outfitted aluminum-tube basket.
"Somebody who's going to use an aircraft for drug smuggling probably is not too concerned about making sure they're flying a true ultralight," said FAA spokesman Ian Gregor in Los Angeles.
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