Grassroots

Budd Davisson,circa 1997

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Of Cement Bags and Airport Hamburgers

Gravity is the enemy. We all know that. It pulls at us constantly, sucking us continually downward making our entire existence a weary battle against something we can never permanently beat.

We can only prove Isaac wrong for annoyingly short periods of time. But when we're flying, we're not really beating gravity. We're just, as accountants like to say about those "special" tax shelters, "deferring" gravity. We're putting off the inevitable. Sooner or later we're going to smack back down where we started. The degree of the smack is directly proportional to the amount of skill and aeronautical cunning we have secreted away in dark corners of our pea sized brains.

Most of us hate gravity. It is the force that stands between us and being able to soar unaided where ever and when ever we want. It's also the force that causes us to continually walk around with our heads down wondering where the next airplane payment is going to come from.

If it wasn't for gravity, all of us would be much better off financially.

If, however, we all feel so incredibly strong about something as insidious and persistent as gravity, why do we aid it in its mission? Why do we continually give it what it needs to help keep us on the ground? We knowingly limit our ability to imitate eagles by supplying gravity with a much needed component of its force.

I am, of course, referring to the universal Airport Hamburger.

If I remember my high school physics correctly, the force of gravity is inversely proportional to the distance between two masses and directly proportional to the amount of mass involved. The more mass, the bigger the pull between two bodies. I'm a little fuzzy on this point (probably reading an av-mag during that class), so don't send me letters because, even if I'm wrong, the argument still holds.

When we're in the air, gravity is a two way street trying to eliminate the distance between us and the Earth. The Earth's mass is trying to pull us down. Our mass is trying to pull the Earth up. I'm pretty sure the Earth usually wins. Or do we meet half way?

The wings, which could be considered our "gravity deferral system," have to generate enough lift to overcome the weight (the mass) they are carrying.

Okay, so now we have gravity trying to suck us back down simply because we're up there and because we have weight/mass. The more mass we have, the harder it pulls. The wings are working their little hearts out to fight gravity and the more weight they have to hold up, the harder they have to work, as well.

And therein is where the airport hamburger comes into play.

We all understand the detrimental effect every pound has on the performance of our airplanes. So we look for light weight starters (12 pounds saved), light weight alternators (4 pounds), and keep the fuel load down (6 pounds per gallon).

We go through all this headache, then, after getting our flying machine all ready to go, we break for lunch.

Here comes The Hamburger! It is incredibly easy after a decade of this kind of behavior to look down and suddenly realize the savings of at least two light weight starters, an alternator, and several gel cell batteries are hanging over your belt. Okay, so I'm not talking about you specifically. But, we all know someone with a few extra pounds. I see one, for instance, every morning when I shave.

As it happens, the "Hamburger Effect" is totally explainable. Let's face it, there's something about having a bad hamburger while watching airplanes that makes it taste good. Ditto airport French Fries: They're often such a weird color, we wouldn't eat them in the real world but at the airport we wolf them down.

I, of all people, should know better. I give forums at Oshkosh where I try to get everyone building an airplane to think of weight in terms of cement bags. 50 pounds added to an airplane doesn't sound like much until you think of it as a cement bag. Cement bags are seldom useful in flight, so why build that much extra weight into the airplane?

Looking at it that way, it's easy to look down and realize we're well on our way to having a cement bag stuffed in our pants.

To make matters worse, we seldom fly alone. I have a couple big-guy friends which means, when we fly together, there is the makings for two miles of cement sidewalk between the two of us.

Of course, when making a bad landing, instead of commenting on the sudden gust, the extreme heat or the weird thermal, we could just blame the airport restaurant "Yeah, I had it wired on short final and then gravity sucked me and that damned hamburger right into the runway!"

We have a wonderful ability to ignore the fact that we are as much a component of the flying machine as the finely fashioned titanium fittings and stringers cross drilled with lightening holes.

But, the Airport Hamburger isn't entirely to blame. Besides, if it wasn't for the lowly burger, a lot of us wouldn't have a rational reason to go places in our airplanes. If we told our non-flying friends we just took off and flew around, at the very least they'd think we wasted time. Going 75 miles away to get a hamburger, however, makes perfect sense.

The fact an Airport Hamburger costs about $100 doesn't enter the argument.

The good news, however, is that winter is coming. With winter comes fat, dense air. Fat air means wings can lift that much more with much less effort. So, I no longer have to feel guilty about overloading my airplane needlessly. Now, the problem has something to do with overloading my jeans.

You'll have to excuse me now. I have a lunch appointment at The Left Seat.