I overheard the conversation between the student and the controller on the radio as I was preparing to take off. I wondered how the student could have made such a mistake and where it was written that inactive runways couldn't be used for taxiing. Later, discussions with FAA Flight Standards, runway safety offices, and ATC policy people revealed uncertainty about whether or not this student pilot was in the wrong.
I received almost 50 comments from readers. Holifield's analogy to railroad tracks summed up most of the responses. "Taxiways are for taxiing, runways are for takeoffs and landings."
Some readers said there shouldn't be any confusion about the notion that "Cleared to cross any runway except the active" doesn't mean to taxi on. They point out that it's made perfectly clear in both the Aeronautical Information Manual and the federal aviation regulations:
A clearance must be obtained prior to taxiing on a runway, taking off, or landing during the hours an ATC tower is in operation. [AIM 4-3-18 a(4)].
The interpretation here is that this means taxiing on any runway, not just the active.
No person may, at any airport with an operating control tower, operate an aircraft on a runway...unless an appropriate clearance is received from ATC. [FAR 91.129(i)] Again, it is assumed that this applies to any runway.
Other readers weren't so sure that the student pilot's action was a violation, but they added that pilots should err on the side of safety. "If in doubt, ask, ask, ask," wrote one CFI. "Safety comes before efficiency. On the runway I get nervous whenever my backside is pointed a direction that something big and fast could be coming from." Another wrote, "As a 12,000-hour ATP, I can tell that you every second I'm on the runway, I'm nervous."
Some readers noted that an inactive runway suddenly could become active. "What would have happened had there been an emergency for an aircraft on takeoff, and the student was on the only runway the disabled airplane could make in returning to the field?" "What if ATC hadn't noticed that the student was taxiing on the inactive runway, and cleared an aircraft to takeoff or land on that other runway?"
Good points.
A few CFIs took the position that the student was not at fault and the controller should have provided explicit taxi instructions. "For decades the policy used by pilots when dealing with the FAA has been 'if it's not prohibited, we can do it.' If the controller wanted this student to use a certain route, it should have been specified."
One said that the taxi clearance without restriction is "pretty much an invitation to have the pilot taxi to the runway any way they feel fit. When they receive a 'taxi to' clearance with no restrictions, in a way they own the airport." He added, however, "But they are ultimately responsible for their own safety. The quickest way is not always the safest."
Another comment suggested that the student's instructor might have led him to believe that taxiing on the runway was permitted. "I'll bet the student learned taxiing on a runway from the example of his instructor. Being an efficient lot, many CFIs 'work the system' to get the more direct route to the active runway. It may have become ingrained in the student's mind."
One instructor noted that we should train our students to inform controllers on initial contact that they are student pilots. "Inserting the words 'student pilot' into the initial call would have given the controller a 'heads up,' and he could have been alert to the first sign of an errant turn."
And finally, one CFI was exasperated that this issue should come up at all. He wrote, "Come on, this should be a no-brainer. Let's not get into an undisciplined frame of mind where the Feds feel it necessary to restrict us even more because we won't use some common sense." He has a point. Most flying boils down to common sense
Blake Holifield is right. I can't see myself driving up a railroad track to get to the next crossing. A road would be better...and certainly smoother. Plus, I wouldn't run the danger of being overtaken by a locomotive.
There was disagreement in the responses over whether or not the student or the controller was at fault. But there was no dispute that the pilot is first and foremost responsible for the safety of the flight. Our conclusion is that cross means cross, not on. Don't use runways at towered airports for taxiing without ATC clearance - and not at nontowered airports either, except when absolutely necessary, and then only with great caution.
Thanks to all readers who responded. Your comments contributed to safer flying for all of us.
Richard Hiner is vice president of training for the AOPA Air Safety Foundation.