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Test Flying an Airplane

What has to happen in order to test fly an airplane?
a) Live in a country that allows it. What would we be, do, if we lived in China?
b) Have a philosophy of life that makes you want to do stuff even if it doesn't pay money. You are a group of purists, who are not motivated by money. Those who interact with us, mostly officialdom, hasn't dealt with, or is not willing to recognize our essential character and what drives us.
c) Arrange your life so that you can make it all happen. Unless you've done it, people won't believe you when you tell them that this is the most difficult part about building & flying your own.
d) Acquire the skills, money, place, friends, family to permit this activity of building. Building and flying is not a solitary activity, at least not the path getting us into the air. Once up it is very much a solitary activity. One's personal life must be in order if we are to succeed. The many abandoned projects speak to this. Those of you who actually got to fly your creation are unique. Proof is that magazines can publish the names, with pictures, of all those who actually flew their creation.
e) Develop a thick hide against officialdom which insists on wanting to play with your toy, even if remotely. Aviation is subjected to regulations not foisted on most other solitary activities. Why is that bureaucracies wish to play with our toys even if vicariously. Is it envy? Why do those who have never built an aircraft, or perhaps don't even own one, largely ignore our needs and cries for help, yet presume to make all decisions for us?
f) Expose yourself to severe criticism from those whose job it is to look over your labour of love before you take to the air. You did your best, and now you find out that perhaps it wasn't good enough. You lay your heart on the line.
g) Psych yourself up to fly. That is easier said than done in that you must muster courage to do it yet check yourself from being negligent.
h) Do it
I did it. I went through all the stages. After 12 years of dreaming, slaving, quitting, agonizing, dreaming, hoping, sweating, dreaming , it flew. I spent most of my nervous energy during the taxi trials. I think my voice on the radio must have been very squeaky and excited. One day I guess I was taxiing a bit too fast and the thing became airborne. From then on I knew I had an airplane, not just a machine.

The inspector came and gave me a list of 37 snags to fix. That took a month. I received my flight permit, which was a major milestone and effectively got one wheel off the ground.

I finally decided to go for full flight one day when the wind and runway direction were right. That decision was almost an etheral one - sort of an out-of body experience - kismet - schicksal, fate - I made a pact with myself that regardless I would make one flight down the runway and land. The idea here was to make sure the airplane was controllable at low speed and for the exercise of landing. It was also to check the lift-off speed. That went so well that I remember sitting there 20 feet off the ground saying to myself why don't I just keep going. Part of me said, "Shoot the puck and go". My previously made decision kicked in and took that choice away. I chopped the power.

So back I came and blasted off for a 40 minute flight, essentially uneventful from a mechanical standpoint.

Thoughts on Test Flying Your Homebuilt

The first flight makes you feel something like a hunter in a forest, stalking a prey that you know is watching you looking for it. Your senses are keen to everything - sound, vibration, smells, instrument readings, control feel, angles, reactions. You make mental notes - you don't dare to let your eyes wander. You look out for traffic and listen to the chatter on the tower. A thousand things demand your attention. If you are thorough you record all your findings once back on the ground. Make sure someone takes a picture of that big grin you'll be wearing!

I landed exhilarated. I was also tired. The high of that first flight lasted at least a week. My wife wouldn't let me do a second flight the day after. She determined that I was too excited to do myself any good. You see, although I have test flown 3 airplanes, I am not a professional. So I waited.

The next 25 hours required to 'wring out' the airplane were spent getting familiar with the various configurations and performance of the airplane. Every hour increased my confidence in the machine. I can say that it takes longer than 25 hours to become thoroughly acquainted with an airplane. I was lucky in that I fly an Aztec, and curiously the Mustang handles like an Aztec - the speeds in all regimes are about the same, the planning is the same, and even the control feel turned out to be very similar. I feel it is crucial that pilots get some recent experience in a similar type of airplane they intend to test fly. Most will have a successful flight even without this experience - if nothing untoward happens. Problem situations may require automatic and correct responses.

Stalls were exciting. The airplane drops a wing sharply. It is clearly not a trainer.

Although the airplane performs well, I am planning changes to upgrade performance. Mostly in aerodynamic clean up. I figure I can eventually get another 20 mph out of it. I've agonized over a paint scheme. I'm busy writing a maintenance procedures manual for it, noting things as I experience them. Make sure you have such things as wiring diagrams, bolt torques, and notes to yourself of things you feel need to be watched.

You will want to make adjustments as you become familiar with the airplane. Get some advice on how whatever you do affects other characteristics. Get someone to look over your pride and joy a few hours into the test program. Love is blind.

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Frank Hofmann
Copyright © 2003