Spring House Cleaning

By H. Dean Chamberlain
Reprinted with permission from the FAA Aviation News

Just as many people do annual springhouse cleaning; many aircraft owners do annual spring aircraft cleaning. The reason is simple. Many personal aircraft are not flown as often during the winter as during the summer. And since many aircraft are tied down outside, it is hard to work on them during the winter months because of the limited amount of daylight and cold weather if you are based in the northern tier of the country. Even if your aircraft is kept in a hanger, you may not have heat in the hanger. If you add in some snow and ice, it is even harder to get to the airport, much less work outside, if you don't have hangar space. All of this adds up to the question of how to clean and prepare your aircraft for the upcoming flying season.

Uninvited Guests

The first reminder is a comment and warning about things that fly, crawl, bite, and sting. In a past FAA Aviation News article, we reported about a major bird-nest building project in the tail section of an aircraft. The photographs we published showed just how much material a bird or two could carry into an aircraft in a few days time. Equally amazing was the question of how did the bird or birds get that material into the aircraft.

As some of you may remember, my personal aircraft restoration project has been ongoing for three years. In those three years, the aircraft has been in a well-sealed hanger with electricity and heat for several months. It spent more time in a hanger that gave new meaning to wide-open spaces. But the most surprising discovery during this whole process was finding a major mud daubber wasp 'housing development' constructed in only a few days while the aircraft was in the well-sealed hangar. The construction site was in the small 'hat' storage area above the baggage compartment behind the rear seat. At the time of discovery, the storage area was full of small aircraft parts and rolls of paper towels. The nest or 'vertical condominium' was suspended from the cloth headliner in about the middle of the storage area. What is surprising about the mud nest was that it was made in the well-sealed hanger, and the nest was surrounded by parts and paper rolls. Where the wasps came from, we never could find out. The only thing we knew for sure was the fact that not only did they get into the open aircraft, but they managed to build such a big nest in seemingly only a few days without anyone noticing. The wasps managed to build their nest even though we were working on the aircraft during this period, and we never saw the wasps - or should I say we are fortunate the wasps never saw us.

This is only one example of what insects can do seemingly 'overnight.' Throughout the restoration project we have had to keep looking for other nests in other locations. Since the aircraft's wings and fuselage have been open more than three years, looking for other nests has been an ongoing project. And yes, we have found a few more as we have started closing up the aircraft.

What this means to you, is if you have not carefully inspected your aircraft for evidence of birds or insects, or things that crawl in the night, you might takeoff with guests you don't want to fly with.

The other problem with uninvited guests is the potential damage they can do. For example, bugs in the pitot system can result in erroneous airspeed readouts. If a bug has made its home in your aircraft static system, do you know what can happen to your airspeed reading during ascent, level flight, and descent if the pitot portion of your system is blocked? What happens if the static line is blocked under these three flight conditions? In addition to a blockage of your pitot or static system lines, there is also the risk of additional damage to your vacuum system and instruments if any of the debris gets sucked into your air-operated instruments.

In the case of nests - such as bird nests or those of mice or squirrels or similar type creatures - the nests, dropped food items, and other droppings can all contribute to corrosion and other damage to your aircraft. Then there is always the possibility of the nest or debris causing a fire or blocking a control function. I was surprised at the size of the wasp's mud nest and how hard it was. It might have blocked my controls if it had been built in a critical area.

Because of my personal experience, I recommend that if you have not flown your aircraft recently that you or your mechanic inspect your aircraft for possible uninvited guests. An inspection mirror and a flashlight are great tools for looking into those hard to see in places. If you find something, not only do you have to remove it, but you need to double check for any residual damage such as the start of any corrosion near or below the nest or for any control interference. And as I have found out, if one critter finds your aircraft a good home, then others may have also found it inviting. You need to really check the aircraft thoroughly.

Cleaning Materials

Depending upon what type of nest you find, you should review your aircraft manual for a list of recommended cleaning material. You don't want to make a minor aggravation into a serious maintenance problem by using the wrong type of cleaner. You can also check with your mechanic for a recommended cleaning method.

Since birds seem to love to sit above hangared aircraft, bird droppings can be particularly difficult to remove. If you plan on cleaning your windshield or side windows, you need to carefully follow your aircraft's recommended cleaning methods. The wrong cleaner or the right cleaner used incorrectly can damage your window or windows even more. You never want to rub or grind anything hard into the surface of the window. If you do, you run the risk of scratching the window. This is why we are all told early in our flying never to rub a dry windshield with a cloth to clean it. This is also why we are told to always gently wash any dirt or dust off a window before using window cleaner on the plastic. It also helps to wipe a window in straight lines rather than in swirls. You want to minimize the risk of causing any type of damage that would make it hard to see through the window. As you know, sunlight passing through a damaged window can make it extremely difficult to see out of the window. This is especially true if the sun is low in the sky.

In replacing all of the windows in my old plane, I discovered an interesting piece of trivia that I had never thought about. I just assumed that breakable plastic was used in my side windows because that was what was available years ago. But I found out there is an important safety issue with replacing windows with the most unbreakable plastic available. If you have an accident and can't open a door, your only way out may be through a side window. If it is unbreakable, you have a problem. If it is breakable, you break it and go out the window.

'House' Cleaning Chores

Other important spring-cleaning areas include the battery compartment. Not only should you check the battery for proper charge and recommended fluid level, if the battery is so constructed, and tight connections; but you should also check for any damage to its casing as well as any corrosive damage to the battery compartment case.

Fuel and oil supplies should be checked for both the proper quantity and quality. If you have not flown much over the winter, water may have found its way into your fuel tanks and lines. Making sure your oil supply is the proper weight for your flight temperatures is important. You may want to replace your oil filter if your aircraft is so equipped.

Cleaning and inspecting your tires and brakes is another good house keeping item. Is the air pressure in each tire the correct pressure? Is everything lubricated?

Have you cleaned out all of the junk and miscellaneous things your aircraft has accumulated throughout its various storage bins, under the seats, and in the baggage area? It is amazing how many items an aircraft can pick up on a trip.

As you clean and wax your aircraft, you might want to replace all of those outdated charts you have onboard.

And finally, as you clean your aircraft and prepare it for another flying season, the most important preparation you can make, as an aircraft owner, is a little self-cleaning. If you have not been flying frequently, you might have a little rust on you. You might want to go to your local flight instructor for a little refresher training. Throw in a few hours of flight time and studying and earn your next phase of 'Wings' under the FAA's Pilot Proficiently Award Program outlined in FAA Advisory Circular 61.91H. The added bonus is that this could also be used in lieu of a required flight review.

So plan now to start the 2003 summer flight season with a clean aircraft and some fun flight training. We wish you a great 2003 flying season, and we hope you avoid those things that fly, crawl, bite, and sting.