By Erik Peterson, Lead Maintenance Technician, Bismarck Aero Center
From a mechanic’s standpoint, I am always amazed – and somewhat scared – at how many people I see jump into their plane that’s been sitting on the ramp, fire it up, and take off without so much as a simple check of fuel levels. I have been a certified A&P since 2004 and have worked in General Aviation (GA) in Bismarck since 2011. I earned my pilot’s license at the University of North Dakota (UND) in 2002. Due to the fact that the UND aviation environment is much more by-the-book than the regular GA world, I was very surprised the first time I saw someone at an FBO just hop in their plane and go. At UND, as a scared student pilot, I wouldn’t have dared to fly in a plane without pre-flighting it.
There are numerous NTSB reports that have lack of a pre-flight as either the cause or a contributing factor that led to an accident. Sometimes NTSB reports seem like they are distant from ourselves, that events like that would never happen to us. From my time as a mechanic in the GA world, I have witnessed many errors that should have been caught in a pre-flight check. Thankfully, it has never caused a problem but could have easily resulted in a catastrophic failure.
We all make mistakes – trust me, as a pilot and mechanic, I know – so I am not here to point blame. It does unnerve me to see some pilots seemingly comfortable with skipping over the simple task of conducting a pre-flight check. It’s easy to read NTSB reports and think, “Well that wasn’t very smart, I wouldn’t let that happen to me!” However, it only takes one little mistake in aviation to cause a life threatening scenario. The following stories are events I have either witnessed firsthand or were shared with me.
When I was getting my pilot’s license, I learned about the importance of sumping my fuel tanks in order to catch contaminants or water in the fuel. A slug of water or some other foreign contaminants can cause your engine to stumble, lose power, or outright quit. In my small UND world, I never got to see firsthand what fuel in the strainer cup looked like, aside from pictures. After UND, my next flying outings were all in rental planes, so once again, I never saw what the water actually looked like.
It wasn’t until a few years later when I had the opportunity to fly a non-rental, non-flight school plane that I finally saw the water. The plane was kept in a hangar, but at some point must have been parked outside in either snow or rain. I was very surprised to see the water in my sump cup and it took about four sumps to finally get it all out. It was such a feeling of relief knowing that I caught the problem before the problem caught me. It was at a small airport, and after my run up I wouldn’t have had to wait for anyone, so it would have been relatively quick from start up to rotation.
Once I had passed the runway threshold, I looked down at the power lines and swampland off the end of the runway and thought about how bad it would have been to attempt to put it down in that terrain. So even if your plane is always hangared, sump your fuel! You never know if someone had to pull it out for 15 minutes to move something else out, and it was raining for those few minutes. Fuel cap gaskets don’t last forever and dry rot on them is something I see quite frequently during annual inspections. It is a cheap and easy fix that should not be skipped.
Another thing I have seen happen more than once in North Dakota is snow plows hitting aircraft tied down on the ramp. In one case the plow hit it hard, but the plane was so small and light the plow driver didn’t even know it had happened. Hopefully, the pilot conducted a pre-flight and noticed the missing wing tip and the tail tie-down ripped off. Don’t rely on others to tell you what has happened to your plane when you weren’t around. I remember another time where the plow just clipped the very tip of the wing and took out the nav light. Although this wouldn’t have resulted in an accident, it would be nice to catch it in time to avoid paying for the replacement parts yourself.
Although pilots do not always think of it, the most critical time to do a pre-flight is after maintenance has been performed, especially an annual inspection. I remember a story a few years back of a pilot thinking the maintenance on his plane had been finished and hopping in it for a flight. In this case the maintenance had not been completed, and the plane was actually waiting for a part to arrive. While it was waiting, the plane was put on the ramp. If the pilot would have looked at the intake of his engine he would have realized that the air filter housing was disassembled and just hanging there. The pilot in me says, “If the mechanic would have flagged the disassembled parts, the pilot wouldn’t have missed it”. Yes, of course the mechanic should have flagged it, but this doesn’t alleviate the requirement for a pre-flight.
However, what if the mechanic did flag the part and our lovely North Dakota winds ripped it off? Sometimes it doesn’t matter how obvious a mechanic can make it look to indicate that something is not together or not ready for flight, because it won’t make a difference if no one looks.
As I mentioned before, mechanics are not perfect. Just like all humans, we make mistakes. During an annual inspection there are numerous items which are taken apart. There are also so many variables that can affect the odds of maintenance being performed improperly or parts being put together incorrectly. For example, the majority of annuals require parts to be ordered, which usually take a few days to arrive. After a few days, it can be pretty easy to forget the minor details of a project. In some cases, the mechanic that began the job might now be on vacation, working on another project, or any number of things, resulting in a different mechanic completing the maintenance.
There are always best practices that can be used to prevent things from getting missed or forgotten, such as flagging items which have been taken apart, or documenting their steps for a clear turnover. However, as stated before, we are all human and we all make mistakes. All mechanics and pilots can do is try their best.
I share all this with you in hopes that you will take the time to do a pre-check next time you prepare for a flight. With a few extra minutes and a few simple steps, you can not be the pilot that took off and didn’t realize the reason their airspeed didn’t work is because their pilot tube cover was left on. Or the person that has an engine fire because they didn’t notice the bird’s nest on top of their cylinders. Or the pilot that has a prop strike from hitting their own tow bar. Or the pilot that has to test their power-off landing skills when their engine dies over the end of the runway on takeoff because they didn’t sump the water from her tanks. Think about it: those few extra minutes could prevent a minor headache, or even save your aircraft – or your life.