Wheels up the wrong way

One of the most amazing feats of aerial wizardry I’ve ever seen occurred before my very eyes in the 1980s. A fellow named Craig Hosking was on the air show circuit. While flying a highly modified Pitts he did something that I would have considered impossible: Craig landed upside down.

The modifications to that Pitts included a complete set of landing gear on what would normally be referred to as the top side of the aircraft. This gave the airplane a unique look in the air, with a set of main wheels and a tailwheel protruding from both the top and bottom of the airframe.

Hosking performed an impressive air show routine that came to a conclusion at touchdown, where the pilot set that amazing little biplane down while inverted.

It was something to see.

Normally, we like to keep the greasy side of the aircraft downward, with wheels firmly touching the ground.

Yet insurance claims and video evidence attest to the fact that an unfortunate number of aircraft mimic the basic look of Hosking’s Pitts by extending their gear skyward — usually unintentionally.

While the Pitts I witnessed landing inverted was good to go that same day, that’s not the case for most airplanes that find themselves upside down on the pavement. They suffer significant damage.

So, let’s look at a few examples of how these fine aircraft find themselves bottom side up and see if there isn’t a way to prevent such nastiness from occurring.

As a Floridian I’m familiar with storm cells that are truly violent. Thunderstorms can roll in from otherwise blue skies, kicking up high winds and pelting rain. For those who have their aircraft tucked safely away in an enclosed hangar, these storms are not of great concern. For those on the ramp, however, there is real danger to be found in and around such powerful meteorological phenomena.

A quick search of YouTube will reveal plenty of examples of aircraft that went temporarily airborne due to high winds, with nobody at the controls. A disquieting percentage of them end up on their backs.

Ouch!

Tie-downs can be our salvation. But tying down an aircraft is not a casual event. It takes planning and some Boy Scout quality knot-tying skills.

Some of us employ ratcheting straps that are easy to use, but these handy dandy devices can cause some pilots to tighten up their tie-downs to a degree the builders never imagined. I’m no structural engineer, but I’m not sure that putting a heavy downward load on a wing is a good idea — especially if there is a risk of a powerful wind coming along to make that wing flex and pull against its restraints.

My theory has always been to tie the airplane down securely enough that it can move, but not far. Like a tree swaying in the breeze I want the airplane to be able to relieve tension when the tie-down ropes hit their limit. It may bounce up and down a bit and dance back and forth, but it won’t fly away. That’s all I’m trying to do. To keep the wheel side down and the airfoils in good working order.

That goes for the tail tie-down, too. A little motion is okay in my book.

However, attempting to make the aircraft an immoveable object fastened securely to the Earth is beyond my intent, and perhaps not good for the airframe in the long run.

Another cause of inadvertent inversion involves straying from the runway. Most often this occurs on landing.

Admittedly, tricycle gear was a serious improvement for aircraft design. Moving that third wheel up front provided a level of stability and directional control that is difficult — if even possible — to achieve in a taildragger. That being said, tricycle gear aircraft are not infallible.

If we should lose directional control for any reason including, but not limited to inattention, that high speed foray into the greenery surrounding the runway may not go well. Nosewheels tend to be small and nose gear tends to be far less robust than our main gear. Should the nose gear fail, the airplane is likely to pitch downward rapidly, digging into the soft soil, resulting in a lightning quick inversion of the aircraft and its occupants.

This can be of great concern if the aircraft has a flip-up or sliding canopy. With the weight of the aircraft upon the only means of exit, this can be an exceptionally exciting time for a pilot and their passengers — and I don’t mean that in a good way.

Speaking of passengers, those in the front seat can be of special concern to a pilot.

I often reiterate before landing, “Keep your feet off the rudder pedals, flat on the floor.”

I may even repeat that admonition more than once. Not so much because I’m prone to repeating myself for pleasure, but because I have seen what can happen when a passenger feeling a bit more anxiety than they’re admitting attempts to brace themselves for landing by using the best footrest they can find. These footrests are also known as the brake pedals.

The least of our worries in that scenario will be buying a new set of tires and tubes, and possibly new rims if the slide along the runway is long enough. That’s a pricey ticket to pay for a nervous passenger who isn’t thinking clearly.

Worse is the possibility that extreme braking during touchdown can cause the aircraft to swap the bottom for the top more quickly than the pilot can react to the problem. Even if the pilot does respond quickly, a pair of locked mainwheels has far more authority than the elevator can muster at landing speeds.

The long and the short of it is, unless you’re Craig Hosking, you should probably make a serious effort to keep the wheels downward on a regular basis. From takeoff to landing and even to temporarily storing the airplane on the ramp, that goal should be included in our mission plan.

If nothing else, the successful execution of that plan will prevent us from having a humbling conversation with our insurance carrier.