IFR Fix: 'It seemed a reasonable clearance'

May 6, 2014

In a movie scene, it’s a dead giveaway that something thrilling is about to happen when the music grows creepy and one of the characters says, "I’ve got a bad feeling about this."

The equivalent moment for an instrument pilot is hearing air traffic control ask, "Where are you going?" The question and its various responses constitute a genre of scenarios that pilots should review for the human-factors and system shortcomings revealed.

Some pitfalls are well known, with remedies long recognized and published. Here’s a pop quiz: What are you expected to say when picking up your clearance if you have filed a route, but revised it before departure?

According to the Aeronautical Information Manual, the pilot should request a full route clearance "to preclude receiving an ATC clearance based on the original filed flight plan when a filed IFR flight plan has been revised" before departure.

If no revision was made to a filed route, an instrument pilot who calls clearance delivery "ready to copy" is always pleased to be cleared to the destination "as filed." Life gets even better if ATC helps by speeding you direct to distant fixes.

But when the pilot of a Beechcraft BE33 single who had been cleared as filed was sent direct to a fix that wasn’t on the flight-planned route, the appropriate question was, "Where am I going?"

"I realized the routing that was in the system was nowhere near what I had filed. Somewhere the system had changed my routing and no FRC (Full Route Clearance) was ever issued," the pilot reported to the Aviation Safety Reporting System. In the future, the pilot said, reading back route clearances—including those issued "as filed"—would include detailing the expected route, as a precaution.

No procedural safeguard is bulletproof. Getting a full route clearance won’t immunize you from a "Where are you are going?" query if you fly northwest to BASYE when you should be flying eastbound to BAYYS—as a Gulfstream G-IV bizjet crew departing New York’s Westchester County Airport discovered after takeoff.

The error had plausibility on its side: Both fixes appear near the airport on the low-altitude en route chart. So "it seemed a reasonable clearance as departing off Runway 16 at HPN on the WESTCHESTER3 heads the aircraft towards the area of BASYE."

File the crew’s Aviation Safety Reporting System narrative under the heading, "That’s where we were going."