Monday, July 2, 2012

Mile High Gliding: A Not-So-Eerie Silence

Date Aircraft Route of Flight Time (hrs) Total (hrs)
02 Jul 2012 SGS 2-33
BDU (Boulder, CO) - Local 1.0 1053.5

On the Nature of Silence

I have heard it said that, for a pilot accustomed to powered aircraft, the silence experienced during glider flight is eerie.

I disagree.

After 1000+ hours flying powered aircraft, I finally seized an opportunity to fly a glider.  Naturally, there was no engine sound.  But the glider was anything but silent.  Rather, the glider sang to me, much in the same way that the flying wires of a vintage biplane hum with joyful power while caressed by the slipstream.  As I pitched from 45 mph to 55 mph, the gentle hiss of atmosphere sliding over the canopy changed, the song becoming more assertive.  From there, gentle forward deflection of the stick brought the airspeed to 65 mph, inciting the glider's crooning to reach an even greater intensity, the airframe beginning to resonate in a throaty wail.  Then, with a return to 55 mph, the song would fade again.

No, I would say that gliders are anything but silent.

Mile High Gliding

"So, why do you want to fly gliders?"  Elliot peered at me expectantly.  We sat in an aged Airstream Trailer docked to a small shack.  Combined, the two oddly matched structures served as a base of operations for Mile High Gliding at Boulder Municipal AirportBoulder sweltered in 90+ °F temperatures and a small air conditioner in the trailer struggled mightily to overcome the day's oppressive heat.

I thought about his question for a moment, pleased that he cared enough to ask.  There are many reasons I have long wanted to fly gliders.  I told him of my mentor, Dave, who flew gliders before tackling powered flight and often spoke of the joys of soaring.  I told him that I believed flying gliders would make me a better stick and rudder pilot, that I expected soaring experience to foster greater insight into energy management.  I told him of my mountain flying experience in the Rockies and how much I enjoyed leveraging soaring skills to make an underpowered Archer climb beyond its abilities.  

"Mostly," I told him, "I want to dip my toe in the water to see how I like it."

The path that led me to Mile High Gliding was, admittedly, a bit convoluted.

In 2007, I had a terrific adventure flying in the Rocky Mountains with a CFI named Reuben.  Fame found Reuben in 2010 when his quick thinking saved a mother and her son from a fiery midair collision.  Reuben was giving the pair a glider ride.  They were still on tow behind a Piper Pawnee when Reuben noticed a Cirrus SR20 approaching on a broadside collision course with their tow plane.  Realizing that the Cirrus and Pawnee were about to collide, he released the tow rope and pitched away.  Soaring through a fireball created by the collision, Reuben delivered mother and son safely to the ground and was hailed as a hero.  By all accounts, he did not even break a sweat.

I sent Reuben an email, expressing my relief that he was safe and sound.  In his response, he suggested that if I ever returned to Colorado and had a desire to take up soaring, he would be happy to fly with me again.  At the time, he was instructing with Mile High Gliding out of Boulder Municipal.

Reuben has since joined the airlines.  But, in preparation for a family vacation to the Denver area, I called Mile High Gliding anyway.  I decided that if the outfit was good enough for Reuben, it was more than good enough for me.

 Unnatural Haze

Driving along the Front Range into Boulder, my heart leaped when I saw the Flatirons again.  I was reminded of riding a Flatiron-generated thermal in the Archer to 13,000' in order to clear Corona Pass.  At the memory, a flutter of excitement coursed through me.

Inside the Mile High Soaring office, I stared across the airfield to where the Flatirons loomed in the distance.  A combination of heat and particulate matter in the air from numerous wildfires conspired to shroud the mountains in haze.  I looked at a Denver sectional on the tabletop and noted that the nearest terrain was only five miles away.  Though the haze was consistent with what I often see at home, it was unnaturally murky for the Rockies.  As though reading my thoughts, some of the guys in the office began to gripe about the visibility.

Across the table from me sat a younger guy, bearded with his hair tied back in a ponytail.  He was studying to be a tow pilot.  As we chatted, we learned that we were both originally from the suburbs of Detroit.  It seems as though I meet people from home nearly everywhere I go.

The chief instructor, Elliot, finished his previous lesson and invited me into his office (the aforementioned Airstream Trailer).  After vetting my reasons for flying gliders, he glanced down at my logbook.

"May I take a look?" he asked.  He quickly thumbed through, rapidly gaining a sense of my past experience.

"What aspect of transitioning to gliders gives pilots like me the most difficulty?" I asked as he closed the logbook.  From my reading, I expected him to say "inadequate use of the rudder".

"Over control," he offered immediately.  "The glider will only require gentle movements on the controls."  It was a refrain I would hear from him often in our short time together.

A Bit of Elmira, NY in Boulder, CO

My ride

It was time to meet the next aircraft to be featured in my logbook.  N2793H is a 1978 Schweizer 2-33A glider manufactured in Elmira, NY (oh, the irony).  With a glide ratio of 22:1, SGS 2-33s are not known as high performance gliders.  But they are rugged, simple, and, according to Elliot, excellent at thermalling.  The 2-33 is as much a classic training glider as the Cessna 150 is a classic training airplane. 

Elliot walked me through the preflight.  Among other things, we inspected the condition of the metal skinned wing and its attachment to the tube and rag fuselage.  The cockpit was rather tight and it appeared that the placement of the spoiler handle relative to my left knee would be particularly problematic.  I would be able to give the glider full left stick or deploy the spoilers, but I would not be able to do both simultaneously.

We walked the glider onto runway 8L, a narrow asphalt strip (20' wide) parallel to Boulder's primary runway.  A Piper Pawnee tow plane lined up ahead of us.  Kevin, the line guy, presented the end of the tow rope to me for inspection.  I was briefly reminded of being offered the wine cork at a fancy restaurant.

"Looks ok to me," deadpanned Elliot when I hesitated.  I nodded to Kevin, who crouched down at the nose of the glider.  He raised his hand, fingers splayed.

"He wants you to open the tow rope release," Elliot explained.  I pulled on the large knob dominating the simple instrument panel.  A moment later, Kevin closed his fist and I responded by easing the release closed again, attaching the Schweizer to the burly Piper idling before us.

Kevin walked to the wingtip, scanned the sky, and gave us a thumbs up.  I waggled the rudder pedals to indicate that I was ready.  The Pawnee responded in kind, then smoothly applied power.


Elliot's guidelines were simple.  On the take-off roll, I needed to steer with my feet (rudder), keep the wings level with aileron, and use gentle movements.

Once aloft, I was to mimic the tow plane's bank attitude, steer with my feet, and avoid climbing too high or dropping too low.  If too low, we would rumble through the tow plane's wake.  Elliot did not mince words about what happened if I climbed too high: "you'll really piss-off the guy flying the tow plane".  When turning, I was to keep the Schweizer's nose pointed toward the tow plane wingtip on the outside of the turn to keep us flying the same path through the air.

Simple, right?

Piper Pawnee tow plane

I only needed to follow Elliot on the controls for the first tow.  It was a strange feeling, being attached to another aircraft by a rope.  The Schweizer's pitot tube extends up and forward from the nose of the glider.  Elliot placed it directly on the Pawnee's tail as though it was a gun sight.

The Pawnee turned north of the airport and we began to climb along a series of virtual switchbacks in the sky.  As we climbed, Elliot gave control over to me.  I suspect that the Pawnee pilot could discern the change in flying duties; I was all over the place.

"Gentle movements," Elliot reminded me again.  "That was about six times more force than you needed to use."  The glider simply did not seem very responsive to me.  At such low airspeeds, the controls were mushy, like an airplane near the stall.  I spent much of the first tow over correcting, just as Elliot predicted I would.

At 9,000' feet, Elliot told me to release the tow rope.  I pulled the release handle and watched the tow rope recoil toward the tail of the Piper.  The Pawnee turned and dove earthward, undoubtedly glad to be unshackled from my ham-fisted flying.

Instrument panel for N2793H

At altitude, I began to acclimate to the glider by making some turns over the Boulder Reservoir.  The bubble canopy afforded a magnificent panorama.  To the east and north stretched barren plains.  To the south was Boulder and, beyond it, Denver.  To the west was the imposing wall of the Front Range.

As is typical for gliders, coordination in turns is monitored by a "yaw string" attached to the pitot mast.  Step on the knot, not the string," Elliot reminded me.  Accustomed to the turn and slip indicator in a powered aircraft where you "step on the ball", my instinct was to step on the string (i.e., apply rudder on the side where the string was deflected).  Step on the knot, I reminded myself every time I looked at the yaw string.

Although the instrument panel possessed an airspeed indicator, it was just as easy to calibrate airspeed based on where the pitot mast crossed the horizon.  Like the yaw string, this served as a simple but functional surrogate for the more complex instruments in my airplane.  Changes in airspeed were easily detected by ear as differences in tone and volume of the slipstream's song.

Stalls were trivial.  The Schweizer is incredibly docile, expressing zero interest in dropping a wing in the stall.  I found that if I did not pull back on the stick assertively, the glider would simply mush along rather than reach a clean break.

To me, the most intriguing aspect of the glider's controls was the trim lever.  Rather than turning a wheel or crank connected to a movable tab on the elevator, trimming the Schweizer simply involved pulling on the trim lever located just forward of the stick.  A ratcheting mechanism below the floorboard actuated with a mighty CLUNK and the tailplane would automatically trim to the current pitch attitude and airspeed.  Neat!

While all of this discovery was grand, we utterly failed to locate any meaningful lift and, after a while, it was time to return to Boulder Municipal.  Challenges in landing included an extremely steep approach profile, a spoiler handle effectively blocked by my own knee, landing on a strip of pavement not much wider than a sidewalk, and, most challenging of all, not flaring.  Most airplanes are flared in the landing - pitched nose high before reaching the ground in order to slow down and plant the main gear.  The Schweizer, on the other hand, is designed to stop on its nose skid.  Sometimes, this generates enough heat to actually fuse the steel skid to the asphalt.  I found the grinding sound of the skid on pavement to be utterly unnerving.  The landing was most definitely not silent.

Landing attitude of the Schweizer 2-33A

Before we departed on the second tow, Elliot suggested I do the flying.  "Remember, gentle movements."  Then he chuckled, "in case you hadn't guessed, we have a rubber stamp here that we place on everyone's foreheads."

"I can't see anything on my forehead," I responded.  "Perhaps an instrument panel placard instead?"

"Ah, but with a rubber stamp, you always carry it with you."

I offered a compromise: "how about a mirror on the instrument panel?"  Elliot chuckled.

My second tow was far more successful and Elliot largely stayed off the controls.  At 8,000', just as I was getting comfortable, we were jostled into an unusual attitude as we ran through a thermal.

"Release the rope.  My airplane," Elliot commanded.

I released the rope and acknowledged that he had control.  Elliot rolled the Schweizer into a tight spiral trying to work the thermal and gain altitude.  It worked for a time.  We gained a few hundred feet before the thermal petered out.  Unfortunately, for the first time in years, the motion of the spiraling glider actually made me nauseous (I think the last time was when my primary instructor first demonstrated turns around a point).

Elliot returned control to me, which helped.  We did some more turns, but my hour of flight time was nearly over.  We made an even steeper approach to the airport than last time, slipping the glider to generate an even greater sink rate than was possible with spoilers alone.

I lined up on the "sidewalk", worked on keeping the wings level, and concentrated on not flaring.

The successful landing was marked with the sound of the skid grinding on the runway.


I asked Elliot how long it takes a typical power pilot to earn an add-on glider rating.  "In your case, not very long.  You flew most of the second tow and I think you would solo quickly, maybe within twenty tows or so."  I have no idea if twenty is a good number or not, but I took this for the encouragement it was undoubtedly meant to be.

At the end of my lesson, The Bear wanted to see the glider.  I led her back to the flight line and Elliot suggested I let her sit inside.  Bright sunshine in her eyes quickly diminished her delight at sitting in the sailplane.

Photo by Kristy.

Overall, gliding was a novel experience for me and more challenging than I expected.  In the end, I think I can say that I dipped my toe in the water and it felt pretty good. 


  1. Great description of the whole experience. We've got a 2-33A at Stewart (only $37/hr, too!) so now I'm really to head down there for some stick time in it!

    Do you think you'll work on the rating neat home now? Or was this just an add-it-to-the-logbook thing?

  2. The experience was enough to convince me that I would like to get the rating, but I'll finish the IFR first. Maybe next year. I'm very glad to have at least tried it out.

    1. Hey Chris I was looking of pictures of 2793H for a school project and ran into your blog. My name is Kevin and I am the wing runner for that day, I love your writing style and had a very similar experience. Hope you will fly with us again soon.

    2. Hi Kevin, thanks for commenting. I don't get out to Denver often, but I am certainly I interested in trying my hand at soaring again. First, I need to wrap up this instrument rating. Thanks for all your help that had been a long time since I last felt like a newbie at the airport!

  3. Chris,

    Great write-up. Glad to hear that you got up in glider. You picked a beautiful place to do it, too. I'm going to visit that outfit the next time I get out to Denver.

    I have found that earning the glider rating is just the beginning of the learning, even more so than the ASEL rating. I'm learning cross-country soaring techniques right now and have found that to be challenging.


    1. Hi Paul - Thanks for commenting. I have enjoyed the tales of soaring on your blog. I have been wanting to try gliders for years, so this was a great opportunity.