Tuesday, August 26, 2008

Express elevator, going down

The other day my instructor and I flew over the shoulder of the volcanic ridge that crowns the island of Hawaii. It was a spectacular flight that took us to the heavens at five thousand feet. The chilly air dimpled our skin, wisps of cloud fluttered at our feet, and stark sunshine streamed into the cockpit. Cows in the fields below looked like pepper spilled on moss.

On the other side of the ridge, I was happily filming some video when he hit me with the first of two surprises that day.

"Autorotation in three-two-one."

Without even giving each count a full second, he flattened the rotor blades and cut the throttle to enter an engineless descent. I was caught a bit by surprise, and you can see the lurch in my footage as gravity is momentarily lost.

"You asshole," I jabbed, jokingly. I tend to curse when I get suddenly spooked by heights, so much so that my first instructor instituted a three-expletives-per-flight rule.

Besides being used for emergency landings, autorotation is the express elevator down in a helicopter. He was using it to quickly lose altitude down the long slope to our next objective, the seaside cliffs of the northern shore. Halfway down, it became apparent that our descent was too steep to clear the cliff edge and glide out over the sea.

Rather than re-engage the throttle, he chose to demonstrate a peculiarity of the helicopter's design. By allowing rotor rotation to slow to 90% of normal RPM, a Robinson R22 pilot can maximize the glide angle in an autorotation, buying more horizontal distance per altitude lost.

It's a maneuver not to be taken lightly. At any value below 97%, the Low RPM Horn begins wailing, alerting the pilot of the vulnerable condition. At any value below 80%, the rotor stalls, and you fall out of the sky.

So there we were, falling almost 2000 feet per minute without any engine power, the rim of a cliff looming to cut short our approach to the sea, and the Low RPM Horn lamenting our imminent demise. I'm proud to say I wasn't really fazed; I just kept filming.

My instructor's tactic worked, and we cleared the cliff with room to spare. I've shared a short clip below. As you watch it, notice how our altitude changes relative to the clouds as we float down from a mile high to nearly sea level.

I'll share my instructor's second surprise that day in another post.

Tuesday, August 19, 2008

Somewhere beyond the sea...

The other day I mentioned "good news," but never finished the thought. That day, I had my flight evaluation with the chief instructor. It went well; by some miracle I demonstrated a respectable entry into autorotation.

The procedure calls for a rapid "Left hand down, right foot forward, right hand back," to settle into a controlled, engine-less descent. It's a precise sequence.

Going into the evaluation, I'd never done it without hands-on assistance, so my procedure that morning was "Left hand down, right foot forward, right hand back, pray." The helicopter cooperated, and I passed, clearing me for solo flight.

Which brings me to this morning: I flew for the first time by myself!

My instructor and I did a short flight to begin, then he got out and cut me loose to fly around the airport a few times. On the radio, I introduced myself as a first-timer, so the control tower was kind enough to slow their machine-gun chatter to a more intelligible pace.

See if you can spot the use of ETL in this video. There's nobody in the bird but me, and a beautiful day for it indeed.

[Edit: This video was originally set to music, Bobby Darin's "Somewhere Beyond the Sea." It was much better that way, but the copyright authorities objected. Oh well, just sing along in your head.]

Monday, August 18, 2008

Marauding manta caught on tape

By some stroke of fantastic luck (I guess?), the underwater videographer was still rolling when that manta ray did its dastardly deed. Be sure to read what happened before watching the video, so you know what to look for. (By the way, I do actually have two arms; I put one in my wetsuit because I was cold.)

Sunday, August 17, 2008

A very personal wildlife experience

There are no helicopters in this post, but it's still worth making. Last night I got kicked in the nuts by a manta ray.

I was on a nighttime snorkel/dive adventure with a local outfit. The way it works is all the divers sit on the bottom, 80 feet deep, and all the snorkelers float on the surface, and everyone points their dive lights into the middle. The column of light attracts clouds of plankton, creating a Las Vegas-style all-you-can-eat buffet for the mantas.

There were over a dozen of them, averaging ten feet across and a thousand pounds each, swooping in great inverted loops with their alabaster bellies brushing just inches from us snorkelers. You can see where this is going.

I was on the periphery of the group, and fairly consumed by the experience, so I didn't notice when all the divers and snorkelers started leaving, taking their lights with them. Before long, I was the only light left, which is the equivalent of being that last lonely triangle of double-fudge cake when a busload of ranchers from the Arkansas Cattlemen's Convention is just finishing their buffet.

Suddenly, every manta within five miles wanted their mouth right in front of me. I was a fragile slice of humanity trapped in eight inches of water above a horde of ancient giants swirling up out of the gloom to assault my tiny candle.

Right about that time, I heard the dive guide call my name to tell me to get moving. I popped my head out of the water to listen, which thrust my hips slightly down into the water.

They may look graceful when they swim, but getting hit by a thousand pounds of anything, even if its a glancing blow, is pretty rough. It's like getting racked by a Volkswagen. Luckily, my thigh took most of the shot, or I might have become the tragic dead end to an otherwise long line of vibrant male virility.

Next time, I'm wearing a cup.

Friday, August 15, 2008

Why don't helicopters go straight up?

If you watch helicopters in action, you may notice that they usually take off and land using a gradual slope through the air, similar to airplanes.

Given that helicopters can rise and descend vertically, why would a pilot opt for a more modest angle?

Three words: Effective translational lift.

Helicopter rotor blades are basically airplane wings that spin in a circle (the rotor disc). Like wings, they create lift when air moves smoothly across their upper surface.

When a helicopter is hovering without any forward movement, it's dragging the air above it straight down through the rotor disc. The blades still create lift, because they are moving horizontally through the air like wings, but the effect is partially corrupted by the air that is descending vertically.

Due to this confused or "dirty" air, the engine has to work pretty hard to generate enough lift to maintain a hover.

As a helicopter adds forward speed, the dirty air is pushed farther and farther to the rear of the rotor disc by undisturbed "clean" air ahead. The faster the helicopter moves forward, the cleaner and more horizontal the air flow, and the greater the lift generated by the blades.

This dynamic is called effective translational lift, or ETL. Effective translational lift increases as the helicopter accelerates forward during take off, eventually reaching a strength that enables the pilot to pull the helicopter into the sky, similar to an airplane.

Weirdly, with ETL the helicopter can actually climb using less engine power than what is required to hover.

Although helicopters do typically have enough muscle to climb vertically through dirty air, it's safer to take advantage of ETL. A vertically climbing helicopter is more vulnerable to an irreversible -- and likely fatal -- rotor stall, for reasons I'll explain in another post.

If a helicopter is heavily loaded, or under certain conditions of air temperature, air pressure, humidity, and wind, the pilot may have no choice but to climb using forward movement and ETL.

In Chickenhawk, a riveting first-hand account of the helicopter war in Vietnam, pilot Robert Mason is forced to rely on ETL to lift his overloaded Huey -- filled with infantry -- out of battlefields being overrun by Viet Cong.

The same dynamic applies to landings. Rather than descending vertically, helicopter pilots will typically maintain forward speed (and ETL) all the way to the final hover over the landing spot.

Thursday, August 14, 2008

A little make-believe

I have some good news from school today, but not much time, so I'll have to get to that later. For now, a quick anecdote...

Yesterday in the local coffee shop there was a kid with a helicopter on his t-shirt.

I told him I was a helicopter pilot (ok, that's a stretch, but easier than explaining the larger truth).

Although I couldn't actually take him for a helicopter ride, he did end up wearing my headset and sunglasses, and I taught him how to ask air traffic control for clearance to land.

Here's a picture, I think his name was Laith (Leyth?). He seemed to enjoy pretending to be a helicopter pilot. And for the record, I did too.

Tuesday, August 12, 2008

I can fly a helicopter

I had a great flight today, and I figure I should make a note of it here to counterbalance all my bellyaching about fear and crisis.

Today, for the first time, I managed every segment of the flight, from pick up to set down, without needing help from my instructor. It was sloppy in places, but even if Grant hadn't been there, I still could have taken off, flown around, and come back in one piece.

Not surprisingly, I had another first: As soon as the lesson was over, I wanted to go again.

The best worst idea I've ever had

In my last post, I explained why helicopter flight school scares the shit out of me. There are several more reasons why it's a horrible idea.

First, it's incredibly expensive. Scratch that, it's absurdly expensive. Any half-witted person would take the money and either invest it or buy something useful. I'm spending it on learning a skill that I won't ever use.

Which brings me to number two: It's a useless skill. Obtaining your private helicopter license is like graduating from elementary school; a lot more training (=time and money) is required for true competence.

Plus, in order to remain competent (and safe), you need to fly frequently. That requires either a job as a pilot or Harrison Ford's bank account. I don't want to be a professional pilot, and I don't see myself having heaps of money anytime in the (near?) future, which makes this whole endeavor, at some point, a dead end.

So, why am I doing it? Well, as I explained to my mother during our conversation, I think I'm learning to fly helicopters precisely because it's so scary and ridiculous. Let me explain.

I fundamentally believe that the only real limits we face in life are self-imposed, usually due to fear, and I like to share that belief with the hope that it will inspire others to move beyond their own self-imposed limits.

I realized: The benefit I get from engaging in an extravagant, terrifying experience with no apparent practical purpose is manifested through this blog.

In short, as I explained to my Mom, I want this blog to serve as an example. My intention is for it to be an emphatic exclamation: Anything is possible!! If it helps one person pursue a dream, no matter how scary or "ridiculous," then it's all worth it.

To which my Mom, an Episcopal priest with a penchant for speaking in the Christian equivalent of Zen koans, simultaneously puzzling and profound, said:

"You know, the best sermons I've ever heard have generally been those which the preacher, more than anyone else in the room, needed to hear."

Hm. Let me think about that for a bit.

Sunday, August 10, 2008

Yup, I'm still scared

The other day I was talking to my dear Mom about this experience, and I said, "It still scares the shit out of me. Every day, I just don't know if I'm up to it."

She laughed and said, "You need to put that in your blog." And then she said something very profound, but first let me articulate why flying still gets to me.

My current instructor, Grant, mentioned that when he was a kid, he used to climb trees so high his grandmother would implore him to come down, but he would climb even higher because he loved the heights so much. Future helicopter pilot, that one.

When I was a kid, I would climb to the second branch, look down, and wonder what the hell had possessed me to risk my life.

Sometimes in the helicopter I still look down through a thousand feet of air and feel my insides seize, but for the most part I can handle the heights, which I suppose is progress. However, that irrational fear has been replaced with a rational one.

That is to say, I no longer fear being sucked from of my seatbelt and out the door through some impossible inversion of the laws of physics, but I am more aware of the real danger in flying helicopters.

Helicopter engines fail. I've personally spoken with pilots who have experienced serious engine trouble in mid-flight. I've seen videos of crashes in which pilots with similar trouble failed to perform autorotation, and died as a result. I've also witnessed firsthand the complexity of performing autorotation.

Every time I watch an instructor fly in autorotation, I'm astounded by their ability to multitask so many things so quickly. I can't even list them all for you, because I don't even know them. But at the very least, the pilot must simultaneously:
  • monitor rotor RPM on the tachometer gauge
  • monitor airspeed on the airspeed gauge
  • monitor descent rate on the vertical speed indicator
  • identify a nearby landing spot, and then maintain nearly constant visual contact with it (while still watching all the above)
  • monitor his own sense of weight (or weightlessness) in his seat
  • make constant, precise adjustments to manual controls to keep RPM, airspeed, and descent rate in extremely narrow ranges
  • make the required compensatory adjustments to the other manual controls in order to balance any of the above adjustments
  • steer to the landing spot
And that's just for the descent. As you near the landing spot, there is another series of rapid, precise actions required to simultaneously stop the helicopter's descent and forward speed, just above the ground -- but not too high (or you crash) and not too low (you just crashed).

I'm not sure how I'm ever going to pull that off. What if my engine fails and I just freeze? What if I'm just practicing engine failure and I freeze?

Plus, although I trust my instructor to successfully manage autorotations, I also know that sometimes instructors don't. It says so right there in the title of Robinson's supplemental safety notice SN-38 for their helicopter, which was issued in direct response to a disturbing trend:

So hell yeah I'm scared. And the more I think about it, the more I realize this fear is only one of several reasons why learning to fly helicopters is the exact wrong thing for me to be doing right now. But I'm still doing it, and I'll explain why (and finish the story about my Mom) in another post.

Saturday, August 9, 2008

Flying traffic patterns over Kona Airport (video)

Here's some video of me flying a helicopter, proof that I'm not making this all up!

I'm doing all the flying in this video, except maybe a little help during the take off. Please note the razor sharp hovering and buttery smooth set down towards the end, a vast improvement over my drunken helicoptering.

By the way, the smoky haze shrouding the volcano in the distance is actually volcanic fog, or "vog" as they call it here in Hawaii. Some days it gets pretty thick.

Thursday, August 7, 2008

Speaking of great stories...

I just finished reading Chickenhawk, Robert Mason's best selling memoir of his tour of duty as Huey pilot in Vietnam. It's probably the single most widely read book among helicopter pilots; you can't be in the helicopter world for long without hearing about it.

I'm sure I'm just one of thousands of pilots who howled with amused familiarity at Mason's description of his first day of flight training.

I can't relate directly to his harrowing accounts of unloading infantry in jungle clearings while enemy gunfire rips through his windshield, but they certainly offer perspective. Some of the maneuvers I've been learning are suddenly less daunting.

Back in the saddle

I wrote last week that the best stories are so successful because they grip us with moments of uncertainty that resonate with our own life experiences. The underlying point is that these moments are not just what make stories exciting, but also what makes life exciting.

As your own life unfolds, the challenge is to remember in the moments of crisis -- in your darkest hours -- that it's all just your story, with you as the hero, and it's precisely these moments that make it a great one.

On Friday, my instructor Lee explained that he had been aggressive with me on purpose. With just a few weeks left of training, he knew that, in order for me to reach my goal of getting my private license, he would have to shove me through the learning plateaus that occur with all flight students.

I appreciate the effort. He began as a very patient instructor, but upon recognizing that we were behind schedule, he opted for another method. It backfired, but he was just trying to get me over the finish line in the time allotted.

Ultimately, we agreed that the goal of obtaining my private license in six weeks was too ambitious. It put unreasonable pressure on both him and me, which became counterproductive to the process. So we threw it out. I can finish that goal back home or another time.

In the meantime, I told Lee that I needed to fly with another instructor. While I intellectually understood Lee's intentions, I also knew that if I climbed back into that cockpit with him again, with all the same stimuli, my emotions would go haywire. Even the thought of it made me tense.

Instead, I flew with another instructor for the past two days, which worked wonderfully. I got my mojo back, and managed to perform several respectable set downs from hover, which is what Lee and I had been working on when I snapped.

I even set down (landed) smoothly when facing away from the wind, which is the most difficult angle, because the wind constantly tries to shove the tail around, as if the helicopter were a weathervane, increasing the risk of catching one skid on the ground and rolling over as you land.

Every pilot I've spoken to about last week has shared a story of their own flight school crisis, meltdown, or emotional blow-up. So, if you're going to learn to fly helicopters, be aware that your crisis is coming. And when it hits, try to remember: It's all just part of the fun.

Friday, August 1, 2008

Dangerous things, and the nature of crisis

The vast majority of fatal accidents in the Robinson R22 helicopter result from two causes: collision and rotor stall.

The collisions are usually wire strikes; a pilot is flying too low over unfamiliar terrain, perhaps following a river or attempting to land in an open field, and the helicopter strikes a power line or structural wire, ripping the aircraft from flight and sending it plummeting to the ground.

Rotor stall is a condition in which, through pilot error, the rotor is allowed to slow down too much or the individual blades' angle against the air becomes too steep. As a result, the smooth airflow over the blades is disrupted, and the lifting force is lost.

In an attempt to recover lift, the pilot may reflexively increase the angle of the blades. This only worsens the condition; the wide surface of the blades against the air causes their rotation to rapidly decelerate to zero, and the helicopter falls from the sky like a stone.

On Wednesday, I suffered the emotional equivalent of rotor stall, and I decided to walk away from helicopters for good. (You may have noticed my last post was about seahorses.)

Over a few flights leading up to that point, communication between my instructor and me had rapidly deteriorated. He became increasingly critical of and impatient with my performance. In response, I became increasingly frustrated, resentful, and less inclined to heed his direction, which I expect only made him more impatient, and so on.

Our lessons were rife with negative, antagonistic vibrations. If you're learning how to play golf at the local pro shop, this dynamic can be frustrating. If you're learning how to fly helicopters, it's dangerous.

Perhaps you can remember a time when you had to execute a critical golf shot, tennis serve, basketball free throw, or a difficult sequence in music or dance. If so, you know that if you allow the mental tension to get into your muscles in these scenarios, it's over before you even try. Your muscles seize at precisely the wrong moment, and you choke.

Flying helicopters is equally physical, and the same dynamic applies, with the added pressure that a choke can be fatal.

Last Wednesday morning, I found myself flying a helicopter in a terrible feedback loop of tension. I was already angry and frustrated, and consequently tense. My instructor was barking instructions at me, making me more tense. Worst of all, I was aware that the tension in my arms and legs made me less capable of flying, which amplified my tension with fear, which effectively paralyzed me. My confidence in my ability decelerated to zero, and my emotional state collapsed.

I ended the lesson early and walked away with barely a word to my instructor, convinced I was finished forever. I never want to feel that unbearable combination of anger and fear again, and I don't know that I'm willing to risk it by getting back in the cockpit.

All adventures, in fact all meaningful journeys of any kind, include crisis in which the adventurer faces overwhelming circumstances, and doubt threatens to plunge toward despair.

The most successful adventure stories are those in which -- as the crisis reaches its climax -- we ourselves are swept into the uncertainty. We don't know whether David will defeat Goliath, whether the three hundred Spartan warriors can withstand a vast army of Persians, or whether Luke Skywalker, alone and under heavy fire, will be able to strike the Death Star's tiny weak point with a perfectly placed torpedo.

These stories grip us because each of us, in our own life's journey, is so familiar with crisis and its excruciating uncertainty. Sometimes, as with David and Luke Skywalker, we triumph. Sometimes, as with the Spartans, we do not.

I went to the airport today to sit down face to face with my instructor and discuss the situation. Now I must consider what was said.