Our Place in the Sun

I was standing on the ramp in Logan, waiting for my buddies Brad and Kim to come back in the club Blanik so I could fly. The Sun felt good but being on the ramp waiting to fly felt better. I knew I was strong enough to fly because I had done 10 pushups that morning, the first pushups I could manage since being hit by rheumatoid arthritis.

And there they were, crossing at midfield. I took out my phone and tried to take a picture, tracking the glider manually as it passed straight overhead. The Sun got into the frame and you can see the result. But the Sun felt good and so did being on the ramp waiting to fly.

I Think You Guys Are Crazy

It was a promising-looking day at the gliderport, and Tim, Ron, and I were rigging our gliders. Well, Tim and Ron were rigging, I am still pretty inept. We know that the only cure for that is to fly more often.

Tim and Ron got there before me, and Tim was talking to a stranger about soaring. He was patiently explaining how we did things and how our club worked. From his conversation, the guy sounded like a pilot. "I've been in 2000 foot-per-minute downdrafts east of the Wellsvilles," he said, actually pointing at the Wellsvilles.

But he didn't look like a pilot. That's hard to do: pilots are a pretty mixed bunch. In my career as a flight instructor, I've had the privilege to fly with people from every walk of life. Well, not every: I can't remember flying with any doctors. I wonder what that means?

So, it's hard not to look like a pilot. I could describe his hair, and mustache, and build, but that would be useless because I can think of lots of pilots with his hair, or his mustache, or his build, or, come to think of it, any hair style, mustache, or build. I've flown with walrus mustaches, Fu Manchus, Boston Blackies, Errol Flynns, and some British Army waxed jobs. Nothing remarkable. And my personal hair style has varied from long and curly to bald to ponytailed and back to bald.

What was it about this guy? I finally realized that he was shirtless. Now, in America, a shirtless man on a hot day is a common sight, except at airports. And it's not that pilots are a modest bunch, as I am sure you know. But in all my years of flying (and AOPA just sent me my [gulp] 25-year-membership pin), I can remember exactly one shirtless flight, between Martha's Vineyard and Nantucket in my Mooney.

We had been on the Vineyard for a few days and had settled into the island mentality. When my friend's cousin mentioned that his son would be arriving at Nantucket, we said "We'll go get him!" We jumped in the Mooney and launched. I was wearing a swimsuit and flip flops. We crossed the channel at 1000', admiring the clear water. We landed in Nantucket, threw the kid on board, switched seats so my partner could fly, and flew back to the Vineyard. My log says 0.4 hours, MVY to ACK. But clearly this was an exception to my usual over-preparation for any flight. It was only when we got back to Jerry's house and I saw my wallet on the mantle that I realized I had flown without a pilot or medical certificate. Geesh, what a loser.

[For the Red Board types out there, we paid for the flight.]

In fact, I can only remember a handful of flights wearing short pants, except in gliders. This is not modesty(hang around at the start of a triathlon to see how immodest people can be), or formality. It's fear of fire.

What they say is that clothing protects you from a flash fire, although not from an extended fire. So, no shorts when I fly.

Come to think of it, our guy was wearing shorts, too. He really didn't look like a pilot.

But I fly gliders in shorts all the time. The reason? No fuel means no fireball if something goes wrong. I usually wear a long sleeve shirt, though, for sun protection.

The conversation drifted in and out, and I was hoping that I might get a little flying out of it, giving him a demo ride. Then he said it:

"You guys are crazy to fly without an engine."

I don't know what got into me. I wasn't thinking about fire at the time, but I was thinking about energy. "An engine turns chemical energy into kinetic energy or potential energy, right?" I asked.

"Right," he agreed.

"And what organ of the body uses the most energy?"

"The brain." He had obviously thought about this a little, his answer was quick.

"And that's our engine," I said. "We've got our brains."

"You guys are crazy," he repeated, and went back to talk with the others. He wasn't insulted or anything; he really thinks we're crazy. I guess it's mutual; I think flying without a shirt is crazy, too.

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Tim and Ron, more experienced than me, released below 2000' above the ground. They got high and headed off cross-country. This was only my fifth flight in my glider, so I took a high tow. But I never got high; I spent 3 hours moving from thermal to thermal within gliding range of the airport. Not a bad flight. I have 11.3 hours in the Jantar, an average of about 2.3 hours per flight. And I still have a lot to learn.

Ron landed about an hour after me, and Tim came in a little later. Tim did his racing finish: he did a low pass on runway 35, the air screaming and his wings wiggling from the load, pulled up, and landed on runway 10.

And that was the only crazy thing about the day.

Energy Crisis

It's the oldest debate in aviation: does elevator control airspeed or does it control altitude? Does power control altitude or does it control airspeed?

Come to think of it, "Who gets left seat?" may be an older debate. But this one is more fun.

Every flight instructor struggles with it. The student asks, and the instructor hems and haws and says things that start "Well, sometimes ...," or draws out a long list of conditionals ("If you're high and the airplane is slow and it's a Tuesday in the northern hemisphere, then you should ..."). Is there a simple answer?

I used to use a flip answer: "Power and pitch control airspeed and altitude; you have to stay coordinated." Well, it's not really flip, but it's not really useful, either. So, it there a useful simple answer?

I believe that I have stumbled on one, in a roundabout way. Let's back up a little bit to another classic instructor - student dialog. The instructor asks how to recover from a stall. The student is confused, because the FAA's publications, followed by the commercial publications, use a lot of flowery folderol about turbulent flow and burbling air to talk about why an airplane stalls rather than saying what a stall is. The thing is, when you give a student the correct definition of stall, it includes the recovery:

A stall means that the angle of attack is too high, so

A recovery means reducing the angle of attack.

Students who have been exposed to this have a dangerous attitude about stall recovery, because they do not have a clear idea that it's pitch, not power, that will save the day. So here's a typical dialog:

Me: How do you recover from a stall?

Student: Add power and ...

Me, interrupting: What do we do in gliders?.

Power has almost nothing to do with stall recovery; stall recovery means reducing the angle of attack. You need power to pull your scared bellybutton away from the ground. (Admittedly, power slightly reduces the stall speed of many light aircraft, so it may in fact aid stall recovery, but that is a secondary effect.)

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So now let us return to the original debate. The solution to the conundrum is to examine the nature of power. Power becomes one of the four forces, namely thrust, although it also involves a small amount of lift at higher deck angles. A force means that there is a change in energy.

Energy is the key.

There are two kinds of energy, potential energy, which is proportional to height, and kinetic energy, which is proportional to the square of speed. Energy is conserved, so if you lose one you have to gain the other. "Trading airspeed for altitude" is how gliders go around; "trading altitude for airspeed" is a favorite chant of airshow announcers, watching some tiny 9G biplane in a screaming dive toward the bottom of the box.

But energy changes. The only way to change the energy is to exert a force. Two of the four forces are important here. Drag tends to reduce energy: it slows you down. That's why gliders are so small and sleek. The reduced drag means that the glider retains more energy. How reduced is the drag? A Cessna 172's lift over drag ratio is about 10:1. My glider's lift over drag is 39:1. At the same weight, the glider has 1/4 of the drag!

The other force is thrust, which tends to increase energy. Thrust speeds you up. No, wait, thrust makes you go up. It's both! Thrust adds energy, which can be in the form of speed (kinetic energy) or altitude (potential energy).

Gliders don't have thrust, and depend on rising air to gain energy. Airplanes can gain a little energy this way, but usually depend on stored chemical energy (in other words, fuel that is converted to kinetic or potential energy.

But you knew this already: "An airplane climbs because of excess thrust." A climb increases the airplane's energy.

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And so we come to the definitive (pardon my hubris) answer on power management during approaches.

If the energy is low, add power;

If the energy is high, reduce power.


In practical terms:

Add power when you are low and slow; you need a lot of energy.

Reduce power if the PAPI is all white; you are high, so you have too much energy.

Leave the power alone if you are low and fast. Raise the nose to convert airspeed into altitude. Just don't let the speed get too low.

Leave the power alone if you are high and slow. Lower the nose to gain speed, and you will lose altitude.

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If we could only find a simple rule for the price of oil.

Windy Evening

When I got home and my wife asked how it had been, I replied "Awesome!"  

Hearing the wind rumbling through the trees in our yard after dinner, it occurred to me that I was no longer night current in singles, and that this would be a great night to fix that.  Here were the METARs:

KPIH 140353Z 23020G28KT 10SM CLR 02/M03 A2978 RMK AO2 PK WND 23030/0300 SLP096 T00221028
KPIH 140253Z 23019G25KT 10SM CLR 02/M03 A2977 RMK AO2 SLP094 T00221028 55000
KPIH 140153Z 24016KT 10SM FEW025 SCT070 03/M02 A2977 RMK AO2 SLP093 T00281017

As you can see (that is, if you are a pilot), it was windy and gusty.  The peak gust was 30 knots, at 0300Z, and it was gusting to 25 most of the time.

[By the way, I was chatting with a couple of Canadian DND pilots this morning, and they  pronounce METAR more like "meter".]

It was a beautiful postfrontal evening, with light years' of visibility.  An hour and a half after sunset there was some glow to the west, but Orion and Sirius were very bright, and Aldebaran was clearly visible, although I could not pick out the Pleiades.  To the north, the big dipper was standing straight up.

I could hear and the feel the Archer's prop reacting to the gusts as I taxied downwind, and as soon as I broke ground I knew that I had made the right choice for an evening's entertainment.  There was a shear layer about 200 feet above the airport, marked by a sharp bump and a 5 knot airspeed rise on the way up (and a loss of 5 on the way down), and I was watching the lights on the ground slide by, alternately from left-to-right and from right-to-left.  The wind correction angles were crazy on crosswind and base, but kept changing on final.  

I flew a few patterns of right traffic, and then crossed the airport sideways at midfield for a little left traffic.  Crossing at midfield meant that by the time I had turned downwind it was time to turn base.

Some glider pilots think that power flying doesn't do much to improve glider flying, but I think a night like this proves them wrong.  Judging where you are in the pattern, and, more importantly, judging where you are going to be in 5 or 10 seconds, is an important skill.  You might react to these judgments differently depending on the airplane, but that is also part of the fun.  

In any case, fly the airplane you are in.  But take what you have learned into every aircraft you fly.