Weren't Listening

I was talking to a friend years ago, a friend who happens to also be the owner/pilot of a Cessna 421, about some flying experience I had had, something involving the L-1011, and the story involved the flight director (FD). I’ve long since forgotten the details of the story, but I’ve never forgotten his response, because he said, “Do you use that flight director thing often?”

I was puzzled and even a little astonished by his question. I used it all the time—every 1011 pilot does. Not having a flight director—flying on “raw data” (basic altitude, airspeed, pitch, roll, rate of climb, and nav position data) is practically an abnormal situation for a 1011. A 1011 pilot— any turbine aircraft pilot, really—will almost certainly fly a couple of raw data approaches in initial training, and a raw data approach is sometimes one of the discretionary items for review in annual training, but normally, meaning 99.9% of the time, flying a jet aircraft means flying using flight director commands. So the question puzzled me, because it showed that he clearly didn’t understand how valuable they were.

So I said, “Well, yah, almost all the time. Why? Don’t you have a flight director in your 421?”

And he said, “Yah, but I never use it. What does it do for you?”

Since then I’ve noticed that he is not at all alone. Most general aviation pilots have no idea what a flight director does, and if they have one never use it. Most seem to think that it just tells you what you know already, so what’s the point, and it kind of gets in the way of seeing the artificial horizon. I’ve noticed also, checking out ads for aircraft for sale, that very minor equipment options often get a big splash: “Rosen sun visors!”, while the existence of a flight director is often relegated to almost an after thought—Bendix Three Axis Autopilot/FD. Most aircraft ads also show cockpit panel pictures, but the pictures almost never show the flight director in view, as if no one cares about something as inconsequential as that. But the fact is, a flight director not only makes flying jet aircraft easy, it can make flying any aircraft easy, especially on approach in instrument conditions.

So what does a flight director do for you? A flight director is a computer that knows what you want to do because you have told it so using panel selectors and buttons, just like you do for the autopilot: maintain an altitude, fly a given heading, track a VOR radial, fly to a waypoint, intercept and fly a localizer and glide slope. It then looks at all the relevant flight data to determine what you need to do at any given instant to achieve those outcomes, and it directs that requirement to a command bar (or bars: more on the two main types of flight directors later) that, if followed by the pilot flying, will accomplish those ends. If, for instance, you have selected Altitude Hold for 8000 feet, and it sees that you are actually at 8025 feet, it will command a slight pitch down. To follow the command you pitch the aircraft down until the aircraft symbol on the artificial horizon matches the flight director command bar. As the aircraft corrects back to 8000 feet, the command bar will move back up slightly, you match that by pitching up slightly, and as long as you continue to match the aircraft symbol with the command bar, you will stay at 8000.

So how is that different from simply doing your normal job as a pilot to maintain an assigned altitude? If you see you are at 8025 feet and are assigned 8000 feet, all you have to do is pitch down slightly with a little forward pressure on the yoke, and wait for the altitude to correct, then release the pressure. What did the flight director do that you wouldn’t do anyway? And the simple answer is, done perfectly, nothing. But the flight director makes it easy. The flight director has all the available flight data in one place, in its computer. It doesn’t have to rely on a scan of all the data the way a good instrument pilot flying by raw data does. It also has a computer generated profile to accomplish the goal as efficiently and smoothly as possible. The flight director knows exactly how much forward pressure is required, and it knows when to start releasing that pressure to perfectly recapture the altitude (or the localizer, or the heading, or any other flight profile). And it knows that if you are off by 100 feet that that will take a bigger pitch change then a 25 foot deviation, and an earlier change in pitch to recapture. The flight director takes all the guess work out, puts everything you need to know in one place, and makes flying smoother and more efficient.

Where the flight director really comes into its own is on approach. If it only served to make smooth corrections to altitude and heading it probably wouldn’t make much sense, but when you are dealing with a very dynamic environment, that’s when putting all this information into a single instrument that tells you exactly what to do makes sense. Think about what happens on a typical instrument approach: first come several altitude, airspeed, and heading changes as you descend and position yourself for the approach (or the heading changes could be tracking changes if you are doing a non precision approach or are in a non radar environment ). Both descending and speed changes require power adjustments. Engine parameters have to be monitored to avoid temperature shocking the engine (assuming a reciprocating engine). Tracking changes, frequency selections, turning fuel pumps on or off, opening cowl flaps, all involve looking away from the primary flight instruments. Descent and landing checklists have to be accomplished. Outside temperatures may have to be checked if it is cold enough for icing to be a factor, and, if it’s hot, convective activity may be a factor. And with all this going on, an intermediate approach course has to be intercepted and, for a precision approach, a glide slope intercepted and for a non precision approach step down points have to be identified and descents begun. It is just a very busy time. Anything that can be done to reduce that workload is a good thing, and that’s what the flight director does because it takes the scanning part out: everything you need to know to fly the approach is shown right in front of you on not only a single instrument, but on the most important one, the artificial horizon, directly in front of you. (The artificial horizon is often called the attitude direction indicator [ADI] on turbine aircraft, and the electronic “glass” version is called an EADI. The picture above is 757/767 EADI.) Wander a little off course while reaching over to change frequencies? When you look back there it is right in front of you: a command bar telling you to bank a little to the left. Didn’t catch the glide slope coming down—you looked down to open the cowl flaps? Command bar shows a pitch down. The flight director doesn’t eliminate the need to scan—the smart pilot is always keeping his or her eyes moving—but it makes the scan much less critical, a backup rather than the primary focus. With a flight director the right thing to do is always right in front of you in the form of flight director commands.

We been saying “command bar” but there are actually two types of flight directors, one that uses a single cue, or command bar, and one that uses two. (The one shown is a double cue command.) The single cue is sometimes called a “bat wing” cue because it looks a little like a wing: to command a fly up the wing goes up, to fly left it tilts left, and to fly up and left it moves up and tilts left. All the pilot has to do is maneuver the aircraft to keep the airplane symbol snugged up against the “bat wing” to execute the selected command.

The second type is sometimes called a “cross hairs” cue because the two cues look like cross hairs on a rifle scope: one vertical bar and one horizontal bar. To command a turn to the left, the vertical bar moves left: The pilot banks left, into the command bar, and when the bank is correct the vertical bar will return to center. Same thing for pitch: Bar goes up, pilot pitches up to match the bar. To command both a left turn and a climb, the vertical bar goes left of center, the horizontal bar moves up from center, and the pilot aims at the point where the two cross: left of center and up from center. So instead of matching the aircraft to a bat wing, the pilot puts the aircraft where the two bars cross—“in the sights.” The main advantage to the bat wing is that it is intuitive and easy—a kid could do it, just tell him or her to keep the aircraft symbol as close to the bat wing as possible without covering it. The main advantage to the double cue is that it is more precise: you can put the aircraft symbol exactly on the cross hairs, whereas with the bat wing there is always either a little bit of a gap between the symbol and the wing, or an overlap. It is still very precise, but not quite as precise.

Prior to going to work for ATA, my only experience with the two cue system was a few hours as a copilot on a Cessna 421, which happened to have that type installed. (Which was also how I knew that my friend’s 421 almost certainly had a FD as well, but I wasn’t sure what kind.) I didn’t use it much because I didn’t really understand how it worked then either and no one else I was flying with at the time seemed to know much about it, or if they did have any desire to show me. Training on it was non existent and trying to figure it out myself wasn’t easy either because it wasn’t intuitive the way a bat wing flight director was. After the 421 I went on to Citations and Falcons, all of which had bat wing flight directors. They were easy to figure out and I used them a lot. Eventually, years later, I ended up at a now non existent charter airline in Boston called Five Star Airlines as an 1011 copilot. The Five Star 1011s came from TWA and had bat wing flight directors as well. So, as far as I knew at that point, the double cue flight director was an earlier technology that had been completely replaced by the “newer” bat wing type command bar and the fact that I still didn’t really know how they worked didn’t seem to matter much because I would probably never see one again. I was wrong, and I was headed for trouble.

The Five Star job was maybe the best job I ever had, so of course it didn’t last. Less than a year later I found myself unemployed and that’s when I went to work for ATA, then known as American Trans Air. I really would have been happy with almost any flying job at that point, but ATA was attractive because it was a lot like Five Star, only bigger, and they had 1011s as well and a base in Boston which was important because that was close to where I was living. What they didn’t have, as I discovered on my first day in ground school, were bat wing flight directors—ATA used the “old” double cue, cross hair type. Great, I thought. On top of having to start at the bottom with another airline, I have to figure out how to use this ridiculous cross hair flight director and act like I knew how to do it all along.

I got through initial indoctrination and 1011 ground school, and several weeks later I found myself, along with my sim partner (who also came from Five Star, Andre Paillex, and who is also now retired and still a great friend), sitting in a briefing room in Miami about to go into the sim for the first four hours of 1011 flight training using a type of flight director that I had almost no experience with.

The sim instructor was a legendary, retired Delta captain named Clark Willard. Clark had so many ratings he had to have several extensions put on his “ticket”—it unfolded like a road map. But he been flying airplanes and instructing in airplanes and simulators for a long time, and, after finding out that we had virtually no experience with the double cue flight director, he tried to put us at ease. He told us that he was going to explain the secret to using it, and, if we did just like he said, we wouldn’t have any problems at all. He said to just forget about snugging up to the bat wing and forget about when and why the needle on this new thing goes left or right or up or down or what it means when it stops moving or when it starts back, and just remember one thing: Put the center of the airplane symbol, which was a dot right in the middle of the aircraft symbol (it’s a square in the flight director shown above—same thing), right on top of the cross hairs—where the vertical and horizontal bars cross. “If they move, you move. Just keep the dot on the cross hairs. That’s all you have to know about this thing. You do that and everything will be just all right.”

Sounded real simple. So we went into “The Box”—the simulator—for our first session. The first session is simple, of course, no abnormals or emergencies, you start with a normal takeoff, some straight and level, speed changes, some turns to headings, some air work—steep turns, stalls, the usual stuff everybody does in any new airplane. We took turns flying, Andre and I, swapping seats so we did all of our flying from the right seat, the seat we were headed for, and we eventually worked our way back to the pattern for vectors to final for a couple of ILS approaches in VFR conditions. I remembered what Clark had said about keeping the dot on the cross hairs and it worked out pretty well, I thought, particularly on the ILS approaches. As soon as the localizer course came alive, actually, before that—the 1011 flight director was smart enough to know it was approaching the localizer course even before the needle came alive—the vertical bar would shift left moving the cross hairs, the aiming point, to the left. We banked to the left to put the airplane dot on the cross hairs and as long as we kept the dot on the cross, tracking the localizer was a piece of cake. When the glide slope came alive we went to flaps 22 at two dots above, gear down a dot above, and then landing flaps at glide slope intercept—the standard approach configuration profile for the 1011. At glide slope intercept the horizontal bar dropped down, moving the cross hairs down, and again putting the dot on the cross started us down the glide slope and all we had to do to adjust for deviations high or low was keep the dot on the cross hairs. It worked great, and I was very relieved to know that adjusting to this new type of flight director wasn’t going to be such a big problem.

So at the end of our first four hours of flight training we found ourselves back in the briefing room, where I fully expected to be told what a great job we had done on our first session, and how he didn’t see any reason why we couldn’t just whip right on through the syllabus without any real problems, and how pleased he was to be working with professionals. (I had a little speech all made up for him, just in case he needed it.) Instead he said absolutely nothing. He sat across the table just looking at us for awhile, and finally he said, “Well, I guess you men weren’t listening when I said, ‘Just put the dot on the cross hairs.’ This is what I meant.” He got up and went to the wall board, one of those white, plastic things that you draw or write on with a felt tip pen that squeaks a lot, and drew a great big circle. He then drew a single vertical line straight down through that circle, and a horizontal line across it. He stood and looked at it for a second, and then he said, “So this circle is the dot. And these lines are the cross hairs. Notice how, when I do that, the cross hairs divide the dot into four quarters, each equal in size. That’s what I mean by ‘Put the dot on the cross hairs'.”

I looked at Andre and he had a very diplomatic, neutral look on his face, but I was thinking, “You’ve got to be kidding me.” This is going to be a long couple of weeks of training. As a practical matter, even if you could put the dot exactly over the cross hairs, the actual cross hairs virtually obliterated the dot—covered it up—unlike his great big circle with two thin lines across it. There weren’t “four quarters, each equal in size,” there was maybe just little bits of the dot just visible underneath the vertical and horizontal bars. We knew he was exaggerating for effect, but it still seemed a little ridiculous.

But I have to say, the lesson took. The next day I didn’t just “put the dot on the cross hairs,” I tried my best to divide that dot into four equal sections. And darn if I didn’t start shooting some pretty good approaches to minimums, the kind where, exactly at decision height, you hear, “Runway” (the standard call out by the pilot not flying when the runway or runway lights have been picked up visually), and you look up and there it is right directly in front of you: approach lights, runway end markings, centerline lights, and big rectangular landing zone markings. Pretty neat. “Don’t touch a thing until you hear ‘50 feet’, you’re doing just fine.” At 200 feet it’s very important that that runway be right in front of you because you can’t be very far off the center line or at all high or low and still make a safe landing that close in. It has to be right there in front of you, and I learned that if I kept that dot on the cross hairs so that it divides the dot into four equal parts, that’s where it would be.

So that’s why I was so puzzled by my friends question about whether I ever used that flight director thing or not. I’m sure there are people who can fly a perfect ILS approach every time without using a flight director, but I’m not one of them. Raw data approaches are still fun, and everyone should practice them now and then to maintain proficiency in case you have to do one, but the flight director takes all the sweat out of it regardless of what type you use. (But I am a total convert to the cross hair system, and it seems to me that that type is now the more common one, at least at the airline level.) I can’t imagine not using one if I have one, and if you have one but have never really figured out what it was for, go find yourself an instructor with some real world experience with flight directors (not all flight instructors have that experience—I didn’t when I was one), or a corporate jet or airline pilot who will fly with you, and go out on a good day and start playing around with it. It could change your life.

A final thought, if you’re still with me:

What’s the relationship between the flight director and the autopilot? Don’t they both do the same thing? And the simple answer is, yes, they do: the same commands can be selected for each and each has the same data inputs, but the autopilot uses that information to actually fly the required profile while the flight director shows you what to do to fly it yourself. In complex installations, each has its own computer and receives its own data inputs, computes its own solutions, and one directs those solutions to the autopilot servos and the other to the flight director command bars. If the flight director and the autopilot are both engaged, and if they both arrive at the same solution, the flight director will mirror what the autopilot is doing: they will agree and the autopilot will appear to keep either the aircraft symbol snugged up against the bat wing or the dot over the cross hairs. If they disagree, the flight director will command something different and that may be the first good clue that a malfunction is imminent. Each serves as a check on the other, which is why when you have two separate systems, which you usually do at the turbine level, the flight director is normally displayed even when the aircraft is controlled by the autopilot. For simple installations, where both are controlled by a single computer, the display is a redundancy when on autopilot, but it is still good to engage it in case the autopilot drops off. Assuming the reason for the disconnect is limited to the autopilot, like reaching a trim limit, and not something common to both the autopilot and the flight director, the flight director will continue to provide guidance for hand flying, which is a very good thing to have when an autopilot suddenly and unexpectedly disconnects. There is just no end to all the good things a flight director can do for you.

KDTW

Airports are like little cities in many ways. Actually, big airports are like little cities, and little airports are more like villages, but in each case they represent microcosms of the cities they serve. In the case of major airports that means they come complete with hotels, restaurants, banks, stores, and an enormous underground, behind the scenes world that is almost organic in the way it maintains the life of the airport.

Airport names usually parallel the city they serve and also often include the name of someone honored: Washington National Airport, for instance, one of the oldest and most historic airports in the country, was recently renamed Ronald Reagan Washington National Airport. (There are many who still call it simply “Washington National,” for many different reasons.) Airports also have familiar three character identifiers: DCA for Reagan National, for instance, BOS for Boston, SFO for San Francisco. Smaller airports don’t get the full three letter treatment but are assigned three character codes: The airport where I began my career in aviation, LaFleur Airport, Northampton, Massachusetts, is 7B2. (It was renamed simply Northampton Airport after Larry LaFleur sold it, but the identifier is still 7B2.)

Major airports also have a four letter ICAO (International Civil Aviation Organization) identifier, an internationally standardized method of identifying major airports. (Or sort of standardized, anyway. As usual in aviation matters, the United States, partially for historical reasons, and partially because we’re just so big and tend to get our way, usually does things a little differently.) The ICAO standard divides the world into regions: Northern Europe is a region, for instance, southern Europe, called Lower Europe, another. Then within each region there are countries, and within each country are airports. The first letter in the ICAO system represents the region, E for Northern Europe, L for Lower Europe, for instance, and the second letter represents the country: G for Great Britain, D for Deutschland, I for Ireland. The problem of having two countries that begin with the same letter is solved by putting them in separate regions: Ireland, Italy and Iceland all get I’s, but Ireland is in the E region, Italy is in the L region, and Iceland is in the B region. Thus Irish airport identifiers all begin with EI ,Italian with LI, and Icelandic with BI.

The last two letters stand for the city, which means that if we assume all 26 letters are available, then 26 times 26 equals 676, and that is the maximum number of airport identifiers available in each country. Thus Shannon Airport becomes EINN, Rome Fiumicino is LIRF, LFPG is Paris Charles DeGaulle, and EDDF is Frankfurt International. With a little bit of familiarity with international airports and some creative guesswork, you can often figure out the airports from the identifiers alone: LIRA means Lower Europe, specifically Italy, and RA is for Rome’s Ciampino Airport (Roma, in Italian, hence RA.) LEMD is also Lower Europe, but the country is Spain (the E in LEMD is for Espana; the names of the countries are in the language of that country), and the city is Madrid. Okay, maybe it takes a lot of familiarity and guesswork, but there is a system.

North America has a somewhat different system. North America is divided into three regions, Canada with a C, Mexico with an M, and the United States with a K. (I’m sure there’s a reason for the K, maybe even a good one, but it doesn’t jump right out at me.) What we also got was not having to use the region, country, two letter airport system, but instead got to add the common three letter identifier to the K. Thus Washington National, DCA, became KDCA, Los Angeles KLAX, Detroit KDTW, and so on. And KDTW is where our story comes in.

If airports are actually small cities themselves, then it stands to reason that life’s comings and goings also happen there, just as they do elsewhere. And not always for the better. One particular incident stands out in my mind, one that made clear to me that airports are more than just places for airplanes to takeoff and land. I had just gotten back to Detroit, my base at the time (full name Detroit Metropolitan Wayne County Airport, KDTW), after having done a “Vegas Turn.” I was riding the employee parking bus, useful also for connecting between terminals—I was on my way to another terminal to get a jump seat ride home. The bus stopped at the main entrance to the Northwest terminal and I saw a bunch of Northwest flight attendants standing outside at the curb as we pulled up, waiting for the bus. I also saw a middle aged, very nicely dressed woman standing there with two other women standing on either side of her, sort of supporting her. The woman in the middle had her hands to her face and was staring somewhat upward, off into space, with a look on her face that was hard to identify, something between confusion and concentration.

The doors opened to the bus, the Northwest flight attendants got on, lots of noise, bags being dragged up the steps, scrambling for seats, shouts of recognition from other Northwest flight attendants already on the bus, and in the midst of all this commotion one of the flight attendants who had just gotten on said, “Did you see that woman on the curb back there? She just found out her son had been killed.”

Then it got real quiet. In an instant we all went from thinking about the day behind us and getting home, to a realization of what we had just witnessed. And I knew I would never again see the entrance to that terminal without seeing that woman’s face.

Big Sky, Montana

I just got back from another week of skiing with my buddies from back east, this time at Big Sky, Montana. (It should be called Big Mountain, Montana, see picture above.) Virtually nothing related to aviation occurred on this trip, unlike the previous one to Snowbird (see “Amazing”, December 12, 2007), except I did see a Socata TBM 850 taxiing at Bozeman Airport, the aircraft pictured in the previous blog “Pro Am”, and, more importantly, I now have a digital camera, a Canon G9, which I took on this trip, facilitating considerably my ability to include pictures. (Virtually all of the previous photos were taken with a Leica M6, a great camera, but film only, which means that I have to have the photos scanned and converted to digital. It works, but it is slow, costs money, and the result is a big step removed from original quality. The direct to digital obviously has many advantages when doing a blog.)

The main reason I wanted to blog something about this trip, aviation related or otherwise, is because of a really funny thing that happened at the airport waiting to go back to San Francisco. Two of my buddies were waiting for an earlier flight to New York, and one of them, Dan, called home to say he was on his way and got his nine year daughter, Dana, on the phone. After the usual chit-chat, Dan said, “It sounds like you picked up a cough while I was gone.”

“No,” she said, “the kitchen’s on fire.”

“The kitchen’s on fire?

“Yah, mommy burned something in the microwave and now the microwave is on fire.”

“Well, maybe you ought to get out of the house!”

“Okay, dad, see you when you get home.”

I guess it wasn’t really a bad fire, but they may need a new microwave. Good nerves on Dana. May make a good pilot someday.

Pro Am

I like to play golf, but I’m terrible and never seem to get any better. Which means I’m always hitting balls out of bounds, or in water hazards, or into the woods. It’s frustrating not only because it means extra strokes every time I do that, but looking for golf balls is a real drag.

When I watch the pros play, they don’t do that of course, or at any rate, they don’t do that very often, and when they do there are usually lots of people around, people who see where their ball went, and sometimes even people who stop the ball from going any further, keeping a bad shot from becoming a horrible shot.

The pros also have some other things going for them that I don’t have (besides actual talent and a lot of experience): they have caddies to help carrying all their stuff, to tell them the exact yardage to anything on the course, and to act as coaches and help with putts. In addition, if a pro has a question about the rules there is an official with every party to answer their question and keep them out of further trouble. Shoot, I could probably break 90 most of the time if I had everything going for me that they do for them.

Of course, I have some things going for me that they don’t. For one thing, I don’t need to worry about the rules much, except in serious tournament play, because the way I play no one really cares how I score it. I also don’t have any TV cameras aimed at me, no is about to take my picture during my backswing, and no one yells, “You da Man!” as I pose, watching my drive soar hundreds of yards down the fairway. Knowing exact yardages isn’t too important either, because I can’t hit the ball an exact yardage anyway. So we each have some things going for us that the other doesn’t—we’re playing two very different versions of golf.

And I got to wondering if the same thing doesn’t apply to aviation, because when I look back at my professional career, and forward to maybe flying just for fun and personal transportation, I am aware of how much help I had as a professional—how much I had going for me thanks to others—and how much tougher the general aviation pilot’s job is. But, then again, the non-professional pilot also has some things going for him or her too. So I decided to try to make up a list for each, a list of what each has going for him that the other doesn’t (which also means “going for her,” but I just can’t bring myself to say “him or her” every time).

My list is not meant to be complete or detailed, just an overview. I put it out there for your comments and responses, which I would very much like to get, both to improve and fill out the list, but also to get your opinions: is this or that item really an advantage, or just a difference, or irrelevant or whatever..

Here's my list:

What an airline pilot has going for him or her that a general aviation pilot doesn’t:*

He knows he’s legal in terms of training, flight physical, and currency, because someone else is watching it for him.

He knows his airplane is legal and airworthy—all certificates are in plain view and maintenance has signed off on it in the logbook.

He has help—a copilot, possibly a flight engineer or international officer—with preflight inspections, W&B, cockpit prep, takeoff computations, copying ATISs and clearances, taxi routings, maintaining a flight log, approach monitoring, problem solving and checklists.

He knows he has a good flight plan that virtually guarantees a safe outcome that someone else (a dispatcher) has prepared and taken equal responsibility for.

He has the most current facilities information in the form of complete NOTAMS.

He knows he can make a safe takeoff, even after an engine failure.

He knows he can reach and land at a safe airport if he loses an engine, and he knows he can go around on the remaining engine or engines at any point prior to touchdown, if necessary.

He knows he can handle virtually any systems abnormality or malfunction enroute.

He knows he has the performance and equipment to handle, or the information to avoid, adverse weather—snow, ice, icing, thunderstorms, low visibilities, turbulence.

He has almost instantaneous access to outside, expert help—company operations, engineering, legal.

He knows his flight is being monitored and that he will be notified if anything significant changes enroute—destination or alternate weather, delays, facility outages, severe turbulence or icing reports, customs problems, curfew problems—anything that might adversely affect the safe outcome of the flight as planned.

He has another set of eyes and ears to catch his little mistakes before they become big mistakes.

What a general aviation pilot has going for him or her that an airline pilot does not:

He only has to comply with Parts 61 and 91 of the FARs.

No one is looking over his shoulder and second guessing him, neither in the cockpit nor from the outside.

He never has to keep an eye on a weak copilot and decide when he needs to instruct or intervene and he never has to fly with a difficult copilot, one that is argumentative, combative, competitive, lazy, uncooperative, or unresponsive.

He doesn’t have to coordinate with a cabin crew and he doesn’t have to make passenger announcements.

He can take as much fuel as he wants, and usually does by filling the tanks.

He has complete freedom to choose where he flies, when he flies, by which rules, and along which routes to an airport of his choice.

He doesn’t have a schedule to keep, which means there is no pressure to arrive on time.

The more time, money, and effort he is willing to expend, the closer he can come to having the best of both professional and general aviation.

*What follows applies to a large extent to all professionally flown operations, but in particular airline ( Part 121) operations. Professional pilots operating under other parts such as Part 135 (air taxi) and Part 91 (corporate) will still have many of these things going for them, but not all will be required or available—there is no dispatch requirement outside of Part 121 scheduled service, for instance.

Track Up

San Francisco has some of the most unusual weather in the world, a fact perhaps first noted by Mark Twain in his now famous quip, “I spent the coldest winter of my life one summer in San Francisco.” Tourists still don’t get it, assuming that San Francisco means California and California means fun in the sun, so pack those shorts and flip flops. My wife and I regularly hike up to Twin Peaks, a 900 foot hill above our house, partially for the exercise and partially for the 360 degree views of the entire Bay area, and there are often vendors there making a nice living selling sweat shirts with Golden Gate Bridge emblems on them to freezing tourists for outrageous prices. The wind off the ocean up there is strong and cold, even in July.

The reason it is cold is because it has just crossed hundreds of miles of ocean that is 50 to 55 degrees at the surface. The reason it is strong is because the central valley heats up to 100 degrees or more every day in the summer, creating a powerful vacuum that sucks that cold air inland, dragging cold fog along with it. The gap known as The Golden Gate, the narrow opening that separates San Francisco and Sausalito (a gap that was there for a long time before a bridge was built to cross it, in fact for a long time before it was called The Golden Gate), creates a kind of venturi, aggravating the wind and fog, and creating, at times, some of the most localized stormy weather in the world. And as you can imagine, the same vendors selling sweat shirts on Twin Peaks also do a nice business at both ends of the Golden Gate Bridge.

In the winter the pattern changes somewhat. The water is still cold, but the central valley doesn’t heat up in the winter like it does in the summer, so cold wind and fog is much less common. But winter is when Pacific storms, many originating thousands of miles away and having a tremendous amount of water and massive blocks of cold air from the Arctic to support them, hit the West Coast. San Francisco is no more vulnerable than any other area along the coast, but it’s unique geography again exacerbates the conditions when one of these storms does hit, the hills along the shore lifting the winds, the Bay itself swirling them, and The Golden Gate accelerating them.

We have such a storm forecast for later today and on through the weekend, January 3, 2008 until January 5, 2008. Heavy rain is forecast, becoming snow as it hits the Sierras, up to five feet, and winds are forecast to gust to 70 miles per hour in the Bay area, up to 100 miles per hour in the mountains. It is forecast to be one of the strongest storms to hit the Bay area in several years. The last such storm hit in November of 2002. I know, because I was flying that night.

I was doing a Maui “turn”, where you leave SFO in the morning, fly to Maui, turn around and fly back later that same day. Very routine, always the same track over, the same track back, visual approach to the north at Maui, often a visual to 28 left at SFO, unless the weather is down and the wind is out of the south, when you can plan on an ILS to either 19 left or right. The only thing that varied a little bit on those turns was the weather.

That night the weather was forecast to be quite stormy coming back to SFO, but nothing that would indicate anything other than maybe some arrival delays and a rough approach. As I remember the forecast was for rain with ceilings of 1000 feet or so, visibility a mile or two, occasionally down to ½ mile, with winds of 25 to 35 knots from the south, right down 19 left and right. Oakland, just across the bay, had the same forecast, so it wasn’t a good alternate that night, but Sacramento was forecast to be much better, the storm really wasn’t supposed to hit it hard at all. So despite the somewhat adverse weather, not going was never really a consideration: we would probably have arrival delays—you always did when the weather went down to instrument conditions at SFO—but we had plenty of fuel for that, and Sacramento was a good alternate if needed, and we had plenty of fuel to get there. The weather would be rough but manageable, we had anticipated delays, and we had a good out, so I was comfortable leaving Maui.

Approaching the coast all seemed well: weather was as forecast with no delays anticipated. Then, suddenly, things changed. Just seconds from PIRAT, a common holding point for arrivals from the west, center told us to hold as published, SFO was closed due to a “microburst.” “Microburst?” I thought. Thunderstorms were possible anytime you have a clash of air masses, but weren’t forecast or expected. But whatever, we quickly slowed to holding speed, programmed the FMC to enter the hold, got an expect approach clearance time, which the controller said was just an estimate, who knew how long the airport would stay closed, and starting figuring up how long we could hold, which looked like an hour comfortably, maybe a little more if we were lucky.

This is one of those times when ACARS, an automated system for communicating with the company, pays for itself many times over. I got on the ACARS and quickly sent a message to dispatch telling them we were holding, gave them our fuel remaining, asked if they had any more information on SFO and asked for the Sacramento weather. They came back that a major storm was going through the whole area, including Sacramento, and all airports were reporting winds of 50 to 60 knots, gusting to 75. The best airport, ironically, was SFO because the wind was right down the runway, but it was closed. San Jose and Oakland both had the same 50 to 60 knot winds, and both had runways perpendicular to the wind. So we decided to wait it out for awhile and hope conditions improved.

They didn’t. As we approached the end of our comfortable holding time, I told the International Officer, a young pilot named Matt Gibbs, and a terrific pilot in his own right—to contact the company directly on the radio and get updated Sacramento weather, and check to see if any other airports had improved, and to tell them that if Sacramento was still the best alternate that we were going to take our chances and divert there. While he was on the radio approach control came on and said, “Amtran 123, Oakland has opened up, we are accepting approaches, you’re number one.”

I said, “Standby, we’re checking with our company,” and he said, “There’s only one opening, you’re it, yes or no.”

I said, “Yes.” I yelled back to Matt, “Tell them Oakland’s open for one arrival, we’re going there.” And we did. It was a wild ride, the aircraft barely controllable, the FO hanging on to anything he could get a hold of, the IO wedged between the jump seat and the center console, and I was hanging onto the controls as best I could trying to keep it upright. I remember at one point glancing down at the EHSI, the electronic horizontal situation indicator, which displays an average wind vector showing the direction and strength of the wind, and it was showing 70 knots directly from the right. I thought about going around, but I didn’t know where else we could go that would be any better. I could have declared an emergency and landed at SFO anyway, a closed airport, but that was a pretty extreme measure and in any case only solved the cross wind problem, not the wind itself. So I continued.

It turned out alright, but a lot of that was just good luck. I got it on, got on the brakes, had to keep flying it all the way to the end of the runway, actually it still wanted to fly even taxiing in, bouncing and bucking all over the place, and taxied to a spot on the ramp in rain so heavy I could barely see the marshaller. It was all he could do to stand upright, but he was able to indicate where to park. (It turned out he wasn’t even a marshaller, but a United mechanic who saw we had nowhere to go and just parked us, all on his own. I wish I’d gotten his name, he was a real hero.) I was so glad to be on the ground, I took a big deep breath, turned around in my seat and all I could see were four big eyes staring at me. I guess we were all pretty scared. I could second guess what went on that night for the rest of my life, but it worked out. We were down, no one was hurt, and nothing was broken.

The most unusual thing that happened though, had to do with the way modern glass cockpits are designed. The EHSI is based on the HSI—a mechanical horizontal situation indicator that is essentially a slaved gyro compass with a course deviation indicator overlay. Because the compass is gyro stabilized and slaved to a remote magnetic reading device, it is a steady and reliable indicator of magnetic heading. With an airplane symbol in the middle, the combined device shows at all times the aircraft heading at the top, and with the proper course set it shows the relationship between aircraft heading and track: when on course, the difference between the two will be the wind correction angle.

The traditional HSI is a mechanical device, but the EHSI is an electronic device and is not limited by its mechanics to a compass rose and a single course indicator, but can be configured in a variety of ways to suit different situations and different preferences or policies. One of the ways is to configure it like the traditional HSI and this is the way many pilots transitioning to EHSIs like to configure it because it is so familiar. Because the heading is always shown at the top in this configuration it is called, logically enough, “heading up.”

But the more common configuration, the one all experienced EHSI users almost always use and the one less experienced users normally transition to as they get comfortable with the EHSI, is called “track up.” That is, instead of showing where the aircraft is pointed, or headed, at the very top, the top shows where the aircraft is going—where it is tracking. Normally the differences are slight and barely noticeable because the difference between the two, which represents the wind correction angle, is usually only a few degrees. With a wind correction angle of five degrees to the right, for instance, with heading up, the top of the EHSI would show the aircraft heading straight ahead with the desired course five degrees to the left of that. With track up, the course would be at the top and the heading bug would be five degrees to the right of that. In either case, if you were to look carefully at the ground you might be able to see that where you were headed and where you were going were off by five degrees, but in almost all cases both heading and track would be close together, one up and one to the side, which one depending on whether you had selected track up or heading up.

I was using track up that night, just as I almost always did, the normal configuration for the 757. But that night, with a 70 degree crosswind from the right and an approach speed of around 140 knots or so, my wind correction angle was 35 degrees to the right of course. I broke out of the overcast at about 1200 feet with what appeared to be good visibility underneath, five or six miles. The EHSI showed me dead on course, straight ahead, but looking straight ahead all I could see was water. I could see the city of San Francisco to the right, so I knew I was in more or less the right place, but I couldn’t find the airport: it was 35 degrees to the left of where I was looking, well outside of my peripheral vision and, in fact, hidden from view by the pillar between the front window and the side window. I was directly on course, but couldn’t see the runway. It took me a couple of heart stopping seconds to figure it what was happening and find the runway behind the pillar. The greater the wind correction angle, the greater the difference between track and heading and the greater the difference between what you see straight ahead and where you’re going. I knew that, in theory anyway, some dim memory from ground school, but after that I knew it for real.

Once we were parked, it took an hour or so for the wind to die down enough for air stairs to be safely driving up to the aircraft and we off loaded our frightened but relieved passengers onto chartered buses that took them back to SFO. An hour or so after that the storm had passed through, SFO opened up again, and we refueled and flew it back there empty for the next day’s launch. Driving home I saw trees down everywhere, and most of the city was blacked out. My wife had long since gone to bed in the darkness and cold—no heat—because she didn’t know exactly where I was but wasn’t worried because she knew I wouldn’t be silly enough to be out flying on a night like that. I read in the paper the next day that winds had hit 100 mph at SFO and a maintenance shed had been destroyed along with a lot of minor damage all around the airport. So maybe it wouldn’t have been such a good idea to have declared an emergency and gone to SFO after all. Not with a perfectly good airport right in front of me.