Wing and Tail Covers for Aircraft Kept Outdoors:
An Interview with Ron Kensey, President of Kennon Aircraft Covers
We asked aircraft cover guru Ron Kensey of Kennon Aircraft Covers in Sheridan, Wyoming, why on earth his wing and tail covers are made of mesh instead of tightly-woven nylon, and what those funny bumps on the top are there for. Ron showed us some interesting photos and gave us a real education in aircraft cover design.
Ron, in past interviews, we've discussed using sunscreens and cabin covers to protect the cockpit from the damaging effects of the sun, and using insulated engine covers together with preheat systems to avoid cold starts. What other benefits do aircraft covers offer?
The next most cost-effective purchase are covers that protect the wings and horizontal tail — the aircraft surfaces that are most directly exposed to the sun.
Why don't you just make a total airplane cover...something like a car cover?
We would like to, and we are often asked to. But it's easier said than done. A car is compact and built so it doesn't catch the wind. An airplane is much larger and more awkward in shape, and is poised to catch the wind. If a strong wind catches a parked aircraft, it will fly...but not far.
Take a look at this picture. It was sent to us by a customer in Palmer, Alaska, whose plane was parked not far from this one. The wind blew, and this floatplane flew. But like I said, not far.
The customer told us he was sure glad that he had a set of Kennon's Spoiler Mesh Wing Covers on his airplane! His plane didn't budge.
What do the Spoiler Mesh Wing Covers do?
Our covers include raised spoilers on the leading edge of the wing cover. They disrupt the airflow over the top of the wing, thereby destroying the lift. So even in a strong wind, your airplane won't fly without you. You can see the spoilers quite well in this photo of a Piper Super Cub that is wearing a set of our wing and tail covers.
Our unique mesh design keeps snow, ice and frost off the flying surfaces — because those particles are larger than the openings in the mesh — but they "breathe" and don't trap moisture the way nylon covers do. They are our most popular winter cover for use in high wind areas. They are also excellent insurance against wind damage any time of year.
You build covers for specific sections of an aircraft. How much of a plane can you cover doing it that way?
Practically all of it, if you're so inclined. But for practical purposes, most owners cover only the most critical areas. What those are depends on the type of airplane, the geographical location, the season, and how much time the owner is willing to spend putting covers on, taking them off, and storing them.
So what do you suggest?
Yes. First, keep the cockpit cool and dry, using either internal sun screens or an external cabin or canopy cover. Next, begin covering the areas that are most directly exposed to the sun — the top of the wings and horizontal tail. This is especially crucial on a fabric-covered aircraft because it can greatly prolong the life of the fabric.
You're saying that fabric-covered aircraft that are tied down outdoors should always be covered?
Absolutely! Here is a picture that another customer sent us. This Maule is tied down in British Columbia. Dr. Gerke had used our Sunblocker Wing and Tail Covers and our wrap-around cabin cover. But you can see the discoloration of the fabric on top of the aircraft where it was not covered.
The cabin cover actually did cover a lateral area across the cabin roof, and you can see clearly in the photo how the covered area escaped sun damage. Needless to say, Dr. Gerke came back to us to cover the remainder of his plane.
It looks like there's a longitudinal strip up the centerline that isn't discolored. Was that strip covered somehow?
No, that is a peak or ridge on the top of the Maule's cabin. It has extra-thick reinforcement, plus the sun doesn't hit its sloping sides quite as directly as it does the flat horizontal surfaces on either side. That's one reason we're pretty sure that the discoloration was caused by the sun, rather than by acid rain. In British Columbia, you wouldn't suspect acid rain anyway.
What's the material you use to build wing and tail covers?
For year-around wing covers, we use a material called "Sunbrella" — the same soft, woven acrylic canvas used to build boat tops and awnings. We use this material because it "breathes" and because it withstands sun exposure very well.
By "breathes" you mean it doesn't trap moisture?
Exactly! Trapped moisture caused mildew and corrosion. That's why we don't use Nylon or similar materials. Besides, Nylon doesn't hold up very well in sunlight.
How do the wing covers fasten to the aircraft?
Every set is made specifically for the particular make and model of aircraft involved. Typically, the cover is fitted to go over the wingtip, and then fastens under the wing with a bungie cord, with a loop tied at the end to soft nylon hooks sewn onto the trailing edge of the wing cover.
What about colors?
Sunbrella comes in lots of colors. We have selected a light gray for building most of our covers this year. I really like it because it goes with almost any paint scheme and doesn't show dirt. Other colors can be special-ordered, though.
Summing up, by covering the windows or canopy, the wings and the horizontal tail, you have most of the critical areas of the plane covered, right?
Yes, those are the most critical areas to protect from exposure. But there's also one more that most owners forget: the prop blades. They are perhaps the most critical flying surfaces on the aircraft, and we think it's a good idea to keep them covered...particularly since our prop covers cost only fifty bucks.