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.

Shell Card

Military charters—troop movements either to or from the United States—don’t work the way scheduled service trips do. They don’t even work the way a normal civilian charter does. Which makes them hard to describe or explain without getting awfully confusing. It’s a little like trying to explain baseball to a foreigner: a very simple game, really, hit a ball that’s been thrown to you somewhere where the other guys can’t catch it. You get three tries, and if the pitcher throws you pitches that aren’t any good, you get to go to first base for free after four of them. Except for foul balls, which count as strikes. Unless you already have two strikes, and then they don’t. And so on. Baseball starts simple and gets complicated fast. Likewise with military charters, but let me try to explain, because unless you understand something about how a military charter works, a good part of this story won’t make any sense, and the not making any sense part will probably then become the focus, which would be too bad because this is really a Christmas story.

A military charter typically starts or ends at an Army air field, an Air Force air base, or a Naval or Marine air station. (We’ll assume here the trip is one “going over”—leaving the US for some hot spot overseas, but the same process happens bringing troops back.) The airplane for that trip has to be flown into the air base from somewhere else—“ferried in”—by one crew, and will be picked up to start the trip by another crew that has commercialed in separately. This allows the working crew—the crew who will begin the actual troop movement—to be fresh and maximizes their duty day, which maximizes the length of the first leg. Because these troop movements typically cover such long distances—Hickam Air Base in Hawaii to Bishkek, Kyrgyzstan, is not unusual, for instance—that first crew almost never takes the troops the whole way. So another crew is prepositioned further down the road—Bangor, Maine, Shannon, Ireland, Frankfurt, Germany, are typical crew change points—and that crew picks up the flight and takes it from there. Typically that crew cannot go all the way either, but hands it off to yet another crew who often complete the final leg to the destination, and do a “turn”—turn the aircraft around and fly it back empty to the crew who brought them the aircraft. That crew has had 18 hours of so of crew rest and they take the airplane back to the first crew, who have had two days or so of crew rest, and that crew brings it back to the States somewhere, wherever it is needed for its next trip.

When everybody gets to where he or she is supposed to be—everyone is in place—and the airplane isn’t delayed anywhere, it all works fine, but even at its best it is a complicated operation. The troops don’t get any stops for rest—they are on the aircraft the entire time from departure in the States to arrival at the final destination. You never hear any complaints, though, mostly because they’re military and it’s just part of the job, but also because they know they are on a civilian airliner with hot meals and pretty girls, and they know that the alternative would be a sling seat on a C5 with MRI’s, and that the closest thing to a flight attendant would be a loadmaster.

ATA, then known as American Trans Air, flew many missions into Mogadishu, Somalia, beginning in December of 1992. The crew changeover points for these missions were typically Shannon, Ireland and Cairo, Egypt. I did several of these missions as an L-1011 First Officer between Cairo and Mogadishu, which meant I had to first “position”—get myself from the US to Cairo using the regular commercial airlines—well enough ahead of the arrival of the actual aircraft to have my legally required crew rest and be ready for my leg. One trip in particular stands out because I was commercialling over on TWA out of JFK to Cairo, and as it happened a very senior TWA crew, consisting mostly of management pilots and check airmen, was also on the aircraft positioning over to do a Mogadishu “turn” out of Cairo as well, just a few hours before our scheduled mission. We exchanged pleasantries, and they said it would be their first mission to Mogadishu, and expressed some apprehension about the whole affair. (I think TWA had contractual limitations on using line pilots for these kinds of trips, which meant management pilots had to do them—I don’t think they were exactly willing volunteers.) Anyway, I said I had been there before, that it wasn’t any real big deal except for the odd chance of getting shot at (nervous laughs all around), but that there were a few things to watch out for which I would be glad to go over if they were interested.

And they certainly were interested. I told them that the airport was basic and limited: one runway, no taxi way, and a small ramp, “small” meaning room for only one civilian wide body at a time (they were going to take in a 747). That meant you had to be right on schedule, and it meant taking a lot of extra fuel in case things didn’t work out and you had to hold waiting for room on the ramp.

“No taxi way” meant you had to turn around at the end of the runway, on the runway itself, and then taxi back to the ramp. The tricky part here is that the runway was only 150 feet wide and wide bodies like the 747 and the 1011 need a minimum of 142 feet to turn around—a very small margin of error on either side—and if you blew it you would bury a "truck"--a whole set of main landing gear--in the sand on the side of the runway, grounding you for days and shutting down the airport. No one wanted to be on the airplane that did that. But, I said, there is good news: it isn’t shown on the airport diagram, but there are extra little half moon shaped turn around points at both ends of the runway, which give you quite a bit more room to turn and really take most of the sweat out of it. They were relived: turning a wide body on a 150 foot wide runway is something most pilots spend their entire careers trying to avoid.

Finally, I said there is no fuel available in Mogadishu, which means you have to tanker fuel—carry extra fuel with you—so that you can go on to Djibouti, the nearest facility that did have fuel. (Djibouti is both a city and a country, like “New York, New York.” It is on the horn of Africa, and is an ally, of sorts, of the United States. Mostly I think they like our aid and our business, but that’s another story.) I told them that Djibouti won’t take credit cards for the fuel, not even American Express, only cash or Captains’ checks (checks the company provides that the captain can use to make cash purchases. Surprisingly, they are accepted nearly everywhere.) One of them said, “Oh that’s no problem, we have a Shell card, it won't be a problem.” That was news to me, but I didn’t say anything. Maybe they knew something we didn’t—they were TWA after all, everyone had heard of TWA, but American Trans Air? (The usual response to "American Trans Air" was, “Is that part of American?”) I said to my captain, “How come we don’t have Shell cards?” He shrugged and said, “Who knows.”

So that was that. We landed in Cairo and went to our separate hotels. The next day we left for Mogadishu and on our arrival overhead the airport we saw their 747 below us, taxiing back into position for takeoff, presumably headed to Djibouti, so we assumed everything had gone alright for them at that point.

This was in December of 1992, months before the infamous "Blackhawk Down" catastrophe, but Mogadishu, in fact, all of Somalia, was already a very dangerous place. Rebels were assumed to have air-to-air missiles, so we took different, random routes over Somalia into Mogadishu each time. (The route from Cairo took us down the length of Egypt, over Sudan, over Ethiopia, and then across Somalia. I never heard of any missiles being launched, but you never knew.) Once on the ground at Mogadishu, the airport itself was squeezed between the ocean and a bluff probably 100 feet high that ran the length of it. Looking up at that bluff from the ramp you could see militia types walking around with rifles, machine guns, and grenade launchers. A lot of troops were actually camped on the airport grounds, and the bad guys would occasionally lob a mortar onto the field just to keep everyone from sleeping too well. Again, not while I was there, but it kept you on your toes. No one needed to tell us that we needed to make a quick turn. Nonetheless, it still probably took two hours or so to off load the troops, get all their gear unloaded and get cranked up and turned around and on our way.

The hop to Djibouti for fuel was a short one, less than an hour, so by the time we got there it had probably been three hours or so since the TWA 747 had left Mogadishu, plenty of time to get to Djibouti and refuel and go on its way. So we were surprised to see it still on the ramp when we taxied in. The captain, the flight engineer, and I all headed into what passed for a terminal, really just a two story building with various government offices, to start the fussy process of paying landing fees, filing ICAO flight plans, and paying for handling, lav cleaning, air stairs, and water service, none of which we needed but were obliged to pay for anyway—your tax dollars at work around the world. We were even more surprised to see the entire TWA crew sitting in the terminal lobby, looking quite disheveled and unhappy—ties had long ago come off—and something much worse than the weariness of an already long day had set in.

“Hey, guys, how’s it going? What are you guys still doing here?” someone said.

After several moments of silence and irritated looks all around, one of them finally said, “They won’t take our Shell card.”

“Wow, bummer. What are you going to do?”

“We’re trying to get some cash wired in, but the company says it could take as long as 48 hours.”

“We tried to tell you” wasn’t what they wanted to hear. After a couple of awkward attempts at sympathy, our flight engineer—flight engineers are, if nothing else, experts in the practical world of thinking on their feet—perked up and said, “You know, $50 can go a long ways in this part of the world.”

“Really?” one said. “Do you think that’s all it would take?”

“I don’t know, but it sure wouldn’t hurt to try.”

So one of them, I think maybe their flight engineer, went upstairs to the fueling office, and came back down after less than five minutes with a big smile on his face. “You were right. They find they can accept our Shell card after all.” Smiles all around.

So we all refueled, got our lavs cleaned and water serviced, paid outrageous amounts of money for it all, and headed out again on our separate ways, which in our case meant back to Cairo where the crew who brought the airplane into Cairo was waiting to take it back to the States.

When we got to Cairo most of us on the crew elected to stay on the airplane and ride it back all or part of the way to the States, even though we had rooms reserved for us in Cairo and could have gotten off there and later made our way back home commercially. But with big first class seats to sleep in and racks of movies to watch, staying on the aircraft with another crew to do the work made getting home a lot easier and a lot quicker. The company didn’t care because we saved them from having to pay for hotel rooms in Cairo and plane fare out of there, so everyone was happy and we set off for the next refueling stop which was scheduled for Shannon, Ireland.

When we got to Shannon most of the crew elected to stay on, but the captain and I had had enough of airplanes for one day, and we were kind of looking forward to a night in Shannon, and we knew we would have an easy trip back to Boston where we both lived the next day. So we got off and were picked up by Conway transporters, our regular crew bus providers, so regular that we knew the drivers by name, and were taken to the Limerick Ryan, our favorite hotel in the Shannon-Limerick area, a place we had spent so much time in it was almost a home away from home. (It has since been converted into something like a retirement home, I think, to the dismay of all crew members from the many airlines that used it over the years.)

The core of the Limerick Ryan was an older Irish mansion, and added to that over the years were restaurants, bars, lounges, and a rather ugly, ‘60’s era tower that housed the actual rooms. (No one minded, you didn’t spend much time in your room.) By the time we got there the public bar was closed, but, one of the great traditions of both English and Irish hotels, the residents’ bar—a private bar for guests only—was still open. (Actually, the residents’ bar has no hours and will stay open as long as there are guests to serve, and after that there is always the Night Porter who will fetch a Guinness for you. You never have to think about a having a Guinness all the way to Ireland only to find out that the bar is closed when you get there; a way will be found to accommodate you.) The residents’ bar was more like a living room, and the staff had decorated it for Christmas, there was a fire in the fireplace and it was all very relaxing and quiet, the perfect end to a long day that had started in Cairo. And then it got even better: someone said, “Oh, Sean, give us a song, will you?”, and Sean said, "O'course I will," and someone else sat down at the piano and Sean sang Christmas carols for us for a half an hour or so, and I was reminded of James Joyce’s great short story The Dead, which also took place around Christmas time in a musical setting with snow falling over all of Ireland.

The next morning, standing outside waiting for Conway to take us back to the airport, there was no snow, but there was the smell in the air of coal being burned, a smell that I loved because it took me back to my childhood, to Sault Ste. Marie, Michigan, where we had lived for three years when I was a boy. And amongst those memories, I tried to imagine how a place like Mogadishu, and a place like Shannon, could both exist at the same time, and how one could hardly be any worse off, and the other could hardly be any better.

Amazing

I just got back from a week of skiing at Snowbird, Utah with some of my old friends from the East Coast—my “ski buddies,” a bunch of guys who regularly meet to ski together. Since our abilities and interests vary somewhat (and ages, too, I’m the oldest of the bunch, which tells you something about where my interest and ability level is relative to theirs), we sometimes go off on our own for awhile. That was just what I was doing, cruising along on one of the easy “groomers” (a slope that has had the bumps smoothed out of it), when two guys wearing similar yellow parkas stopped beside me. They turned out to be mountain hospitality agents, which is something like a Wal-Mart greeter on skiies, and we chatted a bit, and when we got to the part where they asked me what I did, I said I was a retired airline pilot. One of them said, “No kidding? What a small world. This guy here [the other guy in yellow] is an airline pilot too.”

“Really,” I said, “for what airline?” He said, “Continental. How about you?”

I said, “ATA. You have some of our airplanes. We sold you several of our '300s' [a Boeing 757-300, the stretch model] during our bankruptcy.”

“I know,” he said. “I’m on the 757/767. We’ve probably flown the same airplane.”

“Amazing,” I said.

“Want to ski a run together?”

“Sure,” I said. And then they showed me a way down the mountain that I hadn’t known about.

And the other guy in yellow, the one who asked me what I did, turned out to a helicopter pilot and had air lifted most of the lift towers in place years before when Snowbird was being developed. You never know who you’re going to run into on a ski slope.

Engines, More or Less

Most aircraft today have either one or two engines, but it certainly hasn’t always been that way. Historically, the number of engines has corresponded inversely with engine power: the less powerful the engines, the more needed. The B-36 bomber, the first intercontinental strategic bomber, had 10 engines, six huge Pratt & Whitney R-4360 Wasp Major engines, the most powerful and complicated reciprocating engines (recips) ever produced in any significant numbers, supplemented by four jet engines, two on each wing tip. As a young corporate pilot I used to fly with a captain, Richard Howland, who flew B-36’s in the Air Force. He said they almost never came back from a mission with all the engines still running, and often had more than one shut down. The B-52, the successor to the B-36, had eight turbojet engines. The eight engines were not there for redundancy, but because it needed that many to power it given the engines available at the time. .

Pilots love to argue the merits of different numbers of engines, but the fact is there is no right or wrong answer because the number depends on two variables, power required and reliability, and the two are interrelated. As a generalization, most larger general aviation aircraft have two engines because they need that many to be adequately powered. Whatever redundancy results from having more than one engine is secondary, and marginal—better than nothing (except at very slow speeds, where, unless the control response is precise, the remaining engine is often more liability than asset), but not much better. The Beech 58P Baron, a high performance, pressurized twin, is powered by two 325 hp engines, for a total of 650 hp. There are no reciprocating engines currently in production capable of producing that much combined power, hence two. (More powerful recips were made, like the Wright Cyclone shown in a previous post, Gone Wrong, and the R-4360 Wasp, but they have all been replaced by turbine engines.) The most powerful reciprocating engine still in production is the rare and exotic Continental GTSIO-520, a geared monster producing 375 hp. The more commonly available Lycoming 540, the engine that powers the pressurized single engine Piper Malibu Mirage, produces 350 hp. The Beech Baron needs 650 total hp because it weighs 4500 pounds empty and grosses out at 6200 pounds versus less than 3000 pounds empty and a gross of 4300 for the Malibu. There is no way the Baron could replace its two 325 hp engines with a single, existing reciprocating engine and perform adequately, and conversely, the only way the Malibu can carry any more weight would be to replace its single engine with twin recips (or with a turbine engine, which, when done at the factory makes it a Meridian, and when done by retrofit makes it a turbine Malibu). The Baron has two engines because it needs two engines, and the single reciprocating engine Malibu can’t carry any more than it does because it doesn’t have the power to do so.

But, here’s the catch: As engines are tuned to extract more power, they also tend to become less reliable. Common ways to extract more power are to reduce weight and to increase temperatures, often in the form of turbocharging. Turbochargers are nothing more than exhaust driven turbines, operating on the same principle as turbine engines do, except instead of using the turbine to drive a fan or prop, the turbine drives a compressor, increasing the air available for combustion. (Turbine engines also drive compressors, an essential component of their operation.) A byproduct of compression is heat. Weight reduction and heat both lead to less reliability. So to a certain extent you add a second engine not for redundancy, but to reduce the demand for power from those engines and, hopefully, make them be more reliable. So, paradoxically, part of the reason for the second engine is to ensure you never need it.

Early jets, the Boeing 707 for instance, had four engines because the early jet engines, straight turbine engines without a fan, did a better job of converting jet fuel to noise and smoke than they did power. They needed four engines to be powered adequately. But they also were tremendously more reliable than the recips they replaced. So while the four engines provided multiple redundancies, it was seldom needed. The four engines were there mainly for power, not failures.

Adding fans to jet engines not only made them more powerful, but also made them quieter and more efficient. In fact, engine designers quickly figured out that the fan was the component that had the greatest potential for increasing power, and each new generation featured bigger fans with higher bypass ratios—the ratio of air going around the hot section to the air through the hot section. A beneficial byproduct was sound reduction: the cold bypass air muffled the scream of the hot air coming from the compressors and turbines. And with increased efficiency came cleaner burns, which meant less smoke.

Among the first aircraft to benefit from fan jets were the Boeing 727, 737, and the Douglas DC-9. The 707 was also retrofitted with fan engines. The smaller aircraft, the 727, 737 and the DC-9, didn’t need four engines to be adequately powered, and started what would become a trend in airliner design continuing today: fewer and fewer engines. The 727 was, as far as I know, the first three engine aircraft since the Ford Trimotor. Larger, more powerful engines with big fans, the Rolls Royce RB211, for instance, made it possible to design large, wide body aircraft with just three engines, aircraft like the DC-10 and L-1011. Then Airbus, with the A-300, introduced a wide body aircraft with only two engines, and, while controversial at the time, established the trend for virtually all airliners thereafter.

Two things made all of this possible: power and reliability. You have to have both if you want to reduce the number of engines, and the modern, high bypass turbofan engine does that. The very largest aircraft, the 747, the C-5, and now the Airbus 380, still have four engines, for the usual reasons, but as far as I know there is no reason even larger and more powerful engines can’t be developed allowing even super sized aircraft like these to be powered with just two engines someday.

So, how safe is all of this? I have to admit that after almost 15 years of flying nothing but three engine aircraft, the Boeing 727 and the Lockheed 1011, I was skeptical about flying two engine airplanes over long stretches of water—what the FAA calls ETOPS, for Extended Twin Engine Operations. (ETOPS is also jokingly said to stand for “Engines Turn Or Passengers Swim.” It’s funny the first time.) Even though turbine engines almost never quit, I loved knowing I could lose one and still have two left, and I also loved knowing I would still have at least two generators, two engine drive hydraulic pumps, two sources of air and so on. I say, “at least” because the center engine on the 1011 had two engine driven hydraulic pumps, meaning I had the same hydraulic redundancy as a four engine aircraft as long as it was a wing engine that failed. And if the center failed (which it did once for me, see previous blog Gone Wrong) I would be down to two engine driven pumps, but that was what two engine aircraft started with. And I loved knowing that if one of those engines did fail over water it would be a huge non-event: just descend to a lower cruising altitude and continue or turn back, depending on the ETP (see previous article Equal Time Point Considerations). A little bit scarier was thinking about losing another one after that, because then you would be down to your last engine and your last set of fully functional engine driven systems, and fuel remaining could be critical if you had to cruise for any length of time on a single engine, but it could be done, and it was a whole lot less scary than thinking about losing a second engine on a two engine aircraft.

So it was with less than full enthusiasm that I transitioned from the 1011 to the Boeing 757/767. (The 757 and 767 cockpits are identical, except that you step down into the 757 and step up into the 767; the type rating allows you to fly either). But it didn’t take me long to get over my misgivings. The 757/767 has multiple system redundancies, even with just two engines: power transfer units, ram air turbines, hydraulically driven generators, an auxiliary power unit with an electric generator unit identical to that on each of the engines, and so on. But what made it most easy to accept was that not only did the engines always work, but the systems themselves always worked. The 1011 was (I should say “is,” but there are only a few left) an incredible airplane, but it was complex and fussy: little things were always going out on it, usually nothing serious because it was so well designed with so many backups, but many nuisance failures nonetheless. The trip without a “write up”—something for maintenance to fix—or the log book without a deferral—something minor that had been deferred for a short period of time, usually long enough to get it back to a maintenance hub—was rare. The Boeing, on the other hand, just didn’t have failures. It was a much simpler aircraft, much less complex, but rugged: “If it’s a Boeing, it’s going.” The 1011, on the other hand, loved the gate, as they say. Once you could get all those little problems squared away and get it in the air, it was your castle: nothing could touch you. But it would often be sitting at the gate, or on the ramp, long after all the 757s had departed.

So I came to trust, and even love, maybe not in the same way as I did the 1011, but still respect and admire, the 757. It proved itself to me by never letting me down for many hours over many miles of ocean. And the other two engine aircraft flying today, the Boeing 737 and 777 and the entire Airbus family except for the 340 and the 380, do the same thing every day. Because of that record of reliability the FAA now allows two engine aircraft to be flown for as many as 180 minutes away from a suitable airport at single engine cruising speed (and for as many as 207 minutes in the Pacific, three hours and 27 minutes), meaning they can fly virtually any route they want in the world without having to deviate to stay within range of suitable airports. (Specific ETOPs procedures apply, but mostly they just mean everything has to be working—generators, hydraulic pumps, Flight Management Systems, etc.—to be dispatched at the 180 or 207 minute limit.) The FAA is saying, in effect, we don’t expect these aircraft to lose an engine very often at all, and when one does fail we don’t expect the remaining engine to fail in the three hours or so it takes to reach land, ever. (The actual requirement is to demonstrate a shut down rate better than one in every 50,000 hours of flight.) If you can expect an engine to fail less than once in 50,000 hours, it is pretty safe to say that that engine is probably not going to fail during the three hours it takes to fly on one engine to a suitable airport.

Which raises an interesting paradox about probabilities. The odds of pitching a coin and having it come up heads 100 times in a row are astronomical—virtually impossible. But, assuming you have already tossed the coin 99 times, and it has come up heads all 99 times, the odds of pitching heads again on the next pitch are still 50/50. The past record has no bearing on the next outcome. It seems impossible, but it’s true: the fact that it is so difficult to throw 100 heads in a row would seem to tell you that that the odds are getting worse with every toss that comes up heads, but the odds on each toss are still 50/50. The coin doesn’t know. And the odds of losing the second engine are the same as the odds of losing the first: very low, but the same. If the odds were one in 50,000 of losing an engine, either engine, then having lost that engine the odds remain one in 50,000 of losing the second one too.

But wait, you say, doesn’t having two engines give you two chances to lose one? Yes, of course, but each has the same one in 50,000 chance, there are just two of them. The remaining engine doesn’t know the other has failed, any more than the coin about to be tossed knows you just threw 99 heads before it. Flying along for three hours on one engine may sound scary, but the odds that it will fail during that three hours are the same as the odds that the first one would fail in the first place: 50,000 to one, in our example. Nonetheless, human nature being what it is, my guess is that despite having flown thousands of hours in a two engine aircraft before a single engine failed, it would still be a very long and anxious three hours flying on that remaining engine, no matter how many times you told yourself that the second one was no more likely to fail than the first one was. The one that just failed.

Which brings us full circle to the question of the single engine Malibu versus the twin engine Baron—or any other single engine aircraft versus any other light twin. We said that the number of engines always revolves around two issues, power and reliability. The power issue can be solved fairly easily, as long as money is no object. We can increase the power available for the single by replacing the recip with a turbine; we don’t have to add another engine.

So power isn’t the question anymore, we just have to replace the recip with a turbine—exactly what the airline industry and the military did in the ‘60’s and ‘70’s, replacing all of their reciprocating engine aircraft with turbine powered aircraft. Which leaves reliability. And there again the answer is very simple if money is no object: replace the recips with turbines. I don’t have exact figures, but there isn’t any question that turbine engines are more reliable than recips—a lot more reliable. (They also cost a lot more, but that’s another issue that we will get to later.) The reasons are several, but the most obvious is that the turbine engine, even in its turboprop form, is many times simpler than a recip: all the pieces go around in circles, the fuel and air are dumped into a combustion chamber that has continuous, self sustaining combustion, there is no intricate valve or ignition timing involved, no carburetors or magnetos to adjust, and reciprocating motion doesn’t have to be converted to rotary motion. The one thing a turbine engine has to do that a reciprocating engine doesn’t is sustain very high temperatures. That turns out to be a pretty simple problem to solve, though, compared to those for a recip anyway, it just takes money. The metals necessary to withstand those temperatures are very, very expensive. Which is why we still have recips.

For an easy way to see the difference between recip reliability and turbine, compare times before overhaul (TBO) for each. Reciprocating engines typically have recommended TBOs between 1200 and 2000 hours, and require regular maintenance in between, usually on a 100 hour in service schedule, and still often don’t make it to TBO. Turbines typically have TBOs between 3000 and 4000 hours, with minimal maintenance in between, the only major service being a hot section inspection at the mid point for cracks. And they almost always make it to TBO. Turbines are also lighter (for a given amount of power) than a comparable recip, have less vibration and are often quieter. Finally, they burn jet fuel, which is not only cheaper than avgas, but much more readily available (and always will be, whereas avgas, while not an endangered species, is a very small part of refinery production and is no longer universally available). So for all kinds of reasons, turbines are the way to go, if you can just get past that initial cost. (Recips do have one advantage over turbines, and that is that they burn less fuel, but not much less, and that fuel still costs more, so the result is close to a wash.)

So we’d all love to have a turbine engine in our general aviation single or twin, but, of course, money is a factor, and replacing a recip with a turbine can be a prohibitive expense. Assuming we are staying with reciprocating engines, what about this single versus multi thing? To answer that question intelligently, I think we have to start with an acceptance of the relative lack of reliability of reciprocating engines: we may be able to show that turbine engine failures are so rare that we can assume we will never have two fail in a three hour period, but we can’t assume that same degree of reliability with recips. Recips will fail, with much greater regularity than turbines do, and we have to take that into account.

So does that mean that if we are going to fly with recips that we have to have two of them? What about the accident rate for multiengine aircraft, and their miserable performance on one engine? Aren’t we sometimes better off in a single, even if we do accept the fact that it could quit at any time and leave us with no alternative to an emergency landing?

And I think the answer is, “Yes,” sometimes we are better off in a single, or more specifically, some pilots are better off in a single, and some pilots are better off in a twin, depending on their training, experience, proficiency, and currency. A well trained, experienced, proficient, and, perhaps most importantly, current pilot—meaning he or she flies a lot and at regular intervals—will always be better off in a twin than in a single. The single engine performance may be very marginal, even close to nil shortly after takeoff, but it will still be something, and something is always better than nothing. But without good training, and a lot of flying experience in general, and without proficiency at keeping a twin engine aircraft upright on one engine and currency in flying that aircraft, he or she is better off taking his or her chances in the single. Those chances can be improved considerably by careful planning and good judgment: using airports with multiple emergency landing sites, using the longest runways at those airports, and, once airborne, keeping a continuous tally of suitable airports within range and adequate emergency landing sites when out of range, flying around mountainous areas and large bodies of water, flying as high as is practical to increase gliding range, avoiding areas with low ceilings, all are ways to increase your chances after an engine failure, meaning your chances could be pretty good. If you can’t handle a twin engine airplane on one engine really, really well, you’re better off taking your chances on your gliding skills than on your engine out skills. Because when you lose an engine on a single engine airplane, you have one very simple task ahead of you and that is to find some place to land. But when you lose an engine on a twin engine airplane, you have a beast with a mind of its own that will turn on you unless you do something to control it. Single engine safety is only as good as the planning and judgment that goes into it, and multiengine safety is only as good as the pilot flying it. And that’s the long and short of it, more or less.