Glue, paint, and other dangerous things
Ever thought about sniffing glue before your next flight? Of course not! What a silly question. But you may be doing just that and not know it.
Several months ago, I agreed to conduct an instrument proficiency check with a fairly experienced pilot with whom I had flown several times before. The pilot flew from his home base to meet me at another airport after work. I heard him announce downwind on the unicom frequency and went outside to meet him. As I watched his final approach, I noticed that the airplane was high and a little fast, and no flaps were extended.
At the runway midpoint, his Cessna Skylane was still about 50 feet above the surface. I fully expected to see a go-around, but instead he touched down with only about 750 feet of the runway remaining. He immediately locked the brakes, causing a wall of smoke to rise from both main-gear tires. He skidded off the end of the runway onto a grassy overrun and finally came to a stop perpendicular to the centerline.
The airport ramp crew jumped in their truck and motored out the end of the runway to lend assistance. They returned a short time later with the shaken pilot on board. As the pilot stepped from the truck, he looked at me, smiled, and said, "How'd you like that?" I was a little surprised at the flip way he asked the question, considering what had just happened to him. His comment should have been my first clue that something was wrong.
"What happened out there?" I asked, and the pilot replied, "I don't know. This has never happened to me before."
We retrieved the Skylane from the overrun. Fortunately, the only major damage was one blown main tire, although the other tire had a serious flat spot and would also have to be replaced. We secured the airplane, arranged for the tires to be replaced, and headed home.
During the trip home, I quizzed him about his flight. He recited accurately everything he had done wrong that led up to the incident. He knew his airspeed was too fast; he was too high; he didn't extend flaps as appropriate; and he did not go around when it looked like the landing wasn't assured. He admitted he was far behind the airplane. "Did the thought of going around ever enter your mind?" I asked.
"Yes, it did," he answered, "but not until it was too late."
I reminded him that I had flown with him about a dozen times in the past, and I had never noticed any problem with his landings. We were both puzzled at the turn of events. He knew the procedures necessary to make a good landing, but that day he didn't execute any of them. I told him we would put the IPC on hold and work on landings the next time we flew. He agreed.
That night he called me at home. The pilot said he had told his work partner about the landing incident - and she was immediately able to unravel the mystery. The pilot is a specialized painter who restores art objects, and he had been working with mineral spirits all day without using a respirator. His partner said she would have never let him out of the shop had she known he was going to fly.
In short, the pilot was partially incapacitated from chemical fumes - much as though he had been sniffing glue before a flight. The sinister part of this condition is that he didn't realize he was impaired.
Exposure to such toxic substances as solvents, thinners, glues, paint, and other chemical agents produces the same effects as alcohol intoxication - poor coordination, confusion, and disorientation. Mechanics working in aircraft paint and fabric recovering shops are particularly vulnerable to this hazard. An aircraft mechanic who spends all day preparing an aircraft for painting without wearing a proper respirator and then goes flying is an accident waiting to happen. One should make certain that a respirator is used - one that traps the toxic fumes, not one that merely filters out solid particles.
Pilots who receive anesthesia during dental or medical procedures may also be somewhat impaired for 24 hours or more. A few years ago a friend and very experienced aviator inexplicably taxied a J-3 Cub into a pile of rocks during an instructional flight. Like the Skylane pilot, he didn't know why or how he did it, but later concluded that he was still under the effects of the sedative he had been given for a medical diagnostic procedure the day before.
Most primary students are drilled on the danger of alcohol and illicit drugs from day one, but little is covered on more subtle hazards involving other sources of physical impairment. If one of your students does something that is uncharacteristic or abnormal for which there is no clear reason, it would be a good idea to dig deeper into what the underlying cause might be.
FAR 61.53 makes it clear that no person should act as PIC or as a required pilot crew member if he or she has a medical condition that would render him or her unable to operate the aircraft safely. Impairment by chemical fumes or sedatives can be just as deadly as impairment by alcohol or illegal drugs. As a flight instructor, you have the responsibility to ensure that your students are aware of this sinister hazard.
Richard Hiner retired from the AOPA Air Safety Foundation as vice president of training. He can be contacted at firstname.lastname@example.org.
By Richard Hiner