Two-seater plane brings gov to halt

A Cessna 150 is one of the tiniest planes you can imagine: it travels at about 110 mph and can carry only two people who weigh 170 pounds or less each. The plane itself is around 1,100 pounds with a thin aluminum shell--perhaps a third the weight of most cars.

If a Cessna 150 hit a large government building, the impact damage would be localized. People who weren't near the impact site might not even notice. As the Aircraft Owners and Pilots Association notes: "The suicide crash of a Cessna into a Tampa office building demonstrates the ineffectiveness of a general aviation aircraft as a terrorist weapon."

Yet one of these tiny Cessna 150s reportedly strayed into the controlled airspace near Washington, D.C., this afternoon and prompted a panic evacuation of the White House and the Capitol. Politicians, aides, and journalists were told by police to run from the buildings as fast as they could. "Run, this is no joke, leave the grounds," a U.S. Secret Service agent told one CNN correspondent.

But was the panic justified?

By the time the buildings were evacuated, F-16s and Blackhawk helicopters appeared to have been in the air and the feds should have known that the threat was minimal. The area around Washington, D.C., is well-monitored by radar and security agencies should have realized that the plane was a small aircraft (the cruise speed of the Cessna is lower than the slowest speed at which large jets can fly). It should have a very different radar profile too.

There's also a broader question about whether the size of the "controlled airsapce" near Washington, D.C., is too large and raises too many false alarms.

Contrary to popular belief, it's not just the airspace directly over the White House. I'm looking at the FAA's visual flight rules Terminal Area Chart right now, and the "Air Defense Identification Zone" stretches from the east side of the Chesapeake Bay almost to the mountains an hour's drive from DC to the west. Any pilot who wishes to fly in the ADIZ must have an altitude-encoding transponder and open a flight plan.

The Cessna was reportedly N5826G based in Lancaster, Penn. We don't know all the details, but it seems as though the pilot was heading from Pennsylvania to North Carolina, and a GPS-plotted course takes you right through the ADIZ. Older, pre-9/11 maps don't show the ADIZ, and that's led to a series of ADIZ violations especially in 2001 and 2002.

What you won't hear on CNN or Fox News is that the ADIZ was supposed to be temporary. The House Transportation committee said in a report last month: "The ADIZ was never intended to be permanent. The committee believes that the FAA should not make the ADIZ permanent."

For pilots, the timing couldn't be worse: Congress is considering legislation this week to remind the Federal Aviation Administration and the Department of Homeland Security that the ADIZ was only an emergency measure, and to urge the re-opening of Reagan National Airport to general aviation. Now that senators were forced to take to their heels, the fate of that legislation seems to be dim.