Lift and SinkPosted: November 18, 2012 | |
I have always been somewhat of a lunatic, which I attribute to my early days of swallowing bugs whole on a not-so-street-legal motorbike with my Dad, aka Captain Safety. It is true that these mostly ground-based escapades made a firm impression. However, I remain completely bewitched by the heavens and the seas. Wild and unruly places where anything can happen. Where natural forces can and will steal breath from your lungs and the life within your limbs instantly and without even the smallest of consequence. Bewitched maybe, but my time in the heavens and upon the sea has been limited.
As a child my grandfather would take me to the municipal and private airports in and around Houston. We would sit in his car and he would tell me about the small planes as they came and went. This was a way we had fun together. Even in my faded childhood memories, his desire to someday fly was palpable. To my knowledge, he never did.
Some years ago I promised myself that I would someday learn to fly and sail. Both represent for me an ultimate form of freedom.
Gliding has always captured my imagination. Why gliding rather than powered flight? Perhaps the attraction lies in the purity of it. Gliding is sailing, only in three dimensions. Flying at the blessing and mercy of forces infinitely greater than mankind. Closest to the flight of a majestic bird and with a childlike simplicity, much like being the pilot of a life-sized paper airplane.
Because I am tired of the “only if” and “if only.”
Yesterday I took the first step toward keeping that promise to myself. It was a beautiful, crisp fall day as I drove the small country roads to Midlothian, Texas. I arrived at a small airstrip surrounded by simple metal hangars which contained gliders of all shapes and sizes.
The doors of those hangars opened and I spent the first hour learning the basic principles of gliding. That it is not simply about going up, releasing and gliding down. It is about finding, spiraling and surfing upon rising air. And gliding gracefully through the sinking air. The lift and the sink.
There are three kinds of lift, but in this part of Texas, we rely on thermal lift – columns of air that rise from the ground when heated by the sun. A glider pilot searches for and rides the thermals to increase altitude and extend the duration of flight.
Kids, it is beyond obvious that I am no geophysicist, but this is infinitely cooler than I had thought.
The aircraft was a two-seater sailplane. I would ride in front and my fearless instructor in the back. It was explained that we would tow up to 3,500 feet, cut loose the tow rope and fly this graceful thing by adjusting speed and angle while simultaneously responding to the density of the air. I thought, “come again?”
As we reviewed the controls, I had flashbacks of the laughable performance of my paper airplanes and began to wish I had paid more attention in physics class. Cord? Angle of attack? Air density? Pitch? Aileron? What are these words and how are we not going to fall straight to the ground?
We pushed the aircraft out of the hangar and used a golf cart to taxi to the runway.
The pre-flight checklist included testing mechanical elements and making sure that mud daubers hadn’t taken up residence in the pitot tube, a fancy French word for an instrument that measures airspeed velocity. Seen here on the nose of the aircraft. I am no expert, but that’s probably important.
There was a yaw string. When I first heard it I thought he said “ya’ll string” – which made sense because we were going to be in the cabin together and we were in Texas. Ya’ll fly that thing straight, now, ya here? This simple device would tell if the flight was “properly coordinated” or if we were yawing or simply put, oscillating about the y-axis. Again I am thinking, “come again?”
There was a rope. Another simple item with an important function – to connect us to the tow plane. This guy asked if we approve the condition of the rope. “Um…sure, looks good to me?”
A modified agricultural plane would tow us up and I would be responsible for cutting us loose. Which cord do I pull again? Speaking of cord, I also confirmed the location of another important cord. The rip cord on my parachute.
Now for the most important person in this entire scene. My flight instructor, Mr. John Barr. A rather dashing retired commercial airline pilot who would be my tour guide on this, my first time up in this not-so-paper-paper airplane. I wonder if he was aware that I only absorbed about 1/10 of the information we just reviewed.
Once up to the target altitude, we dropped the cord, banked to the right and then leveled off. It was silent.
Then John let me take the controls. At least I think he did. Immediately my mind starting processing boatloads of information. Is our pitch correct to maintain the right speed and avoid stall? What’s my yaw string doing? Damn, my right wing keeps going up…more aileron! A little rudder – right or left pedal? There goes that right wing again, dammit. What’s my altitude? Wait, I have to subtract how far we are above sea level? I am expected to do math RIGHT NOW?
A high-pitched alarm sounds, then speeds up faster and faster. John says, “we have lift!” We check if traffic is clear and then bank hard to the left. That is the aileron, right? Wait, I think I might be catching on. We go around in circles for a few minutes, gaining altitude. Then John asks me, “how is your stomach?” I reply, “all good, this is amazing.”
Then the alarm quiets and we are in stable air. We gained 300 feet that time.
That right wing is up again, dammit. Get ‘er down.
A few moments later, the alarm sounds again, this time is sounds more flat. This is sinking air. He explains that we simply find the right angle to traverse the sinking air until we reach neutral or rising air once again.
In total we found about 1000 feet in lift during that flight. After 35 minutes in the air, we reached final approach altitude. This is where it gets tricky, right? Line her up, put her down, stabilize the wings, apply the brakes. And I am back on the ground.
Driving back down those country roads I thought about what I had just done and learned. It was so much more than I had imagined. It isn’t passive soaring. It is actively seeking out and riding the lift and finding just the right angle to traverse the sink. Both are inevitable and one can’t exist without the other.
Lift and sink. A simple truth.
I spent the balance of the day at my local Half Price Books voraciously reading the Joy Of Soaring by Carle Conway and reflecting upon my first experience with gliding. A day that taught me as much about myself as I did about the world around me. Why had I waited so long to so something I had so longed to do?
Who cares. It’s done and when can I do it again?
A special thanks to the patience and encouragement of my instructor, John Barr, and the infectious enthusiasm of the kind folks at the Texas Soaring Association in Midlothian, Texas.