Enough is Enough

Aviation has lots of folksy sayings, most of which, in my opinion, are more often wrong than right. One of the more familiar is, “The only time you have too much fuel is when you are on fire.” It’s clever and it’s funny, but it isn’t true.

Of course we always want to have plenty of fuel, and figuring out what “plenty” is is the point of this post, but that doesn’t mean more is always better. More is certainly not better after a partial loss of power, for instance, regardless whether that loss was caused by a twin engine aircraft losing one engine or a blown cylinder or burned exhaust valve in a single. Nor is more the answer to trying to out climb trees on takeoff, to carry a load of ice, to try to top severe turbulence, or to fly out of down drafts from mountain waves. Fuel has weight, weight carries a performance penalty, and there are any number of situations where performance is more critical than endurance. So it’s just kind of stupid to say, “The only time you have too much fuel is when you’re on fire,” and, what I really don’t like about it is that it rationalizes careless flight planning.

One of the more familiar discussions pilots of high performance aircraft typically have is, how much fuel do you want to land with? What are your personal minimums for fuel? At what point does fuel get so low that you say, “Enough. I’m landing at the nearest suitable airport”? I remember having this discussion with several other pilots years ago when I was flying Citations and Falcons for a company in New Hampshire. The Chief Pilot, Stu Jones, was there too, but didn’t get involved in the conversation. That didn’t surprise us because he was not a big talker but when he did say something it was often quite clever and usually very funny. Finally someone asked him what his number was, and he said, “I always try to land with some.” That was funny. And, of course, directly to the point. Landing with “some” is what it is all about. One of the sayings in aviation that I do like is, “Takeoffs are optional, landings are mandatory.” Once airborne, sooner or later the aircraft is going to land, with or without the benefit of power. It’s always better to do it with power.

I started out in aviation in gliders and my first solo was in a glider. Gliders are great fun and a great way to get into aviation, and they are neither scary nor dangerous just because they don’t have engines. They do have “power", but it isn’t in the form of an engine, it is in the form of excess speed and altitude. From Day One in gliders you learn to enter the pattern with more altitude than needed to simply glide to a landing, and with more speed than needed to simply stay in the air. Both are then gradually dissipated, using spoilers, to maintain the desired glide path. You “add power” by reducing the amount of spoilers, and you “reduce power” by increasing the amount. The rough equivalent of a dead stick landing in a glider is arriving over the airport with minimum airspeed and altitude. In that case, you better get it right the first time, just like any dead stick landing.

The reason I started thinking about this again was because I noticed several ads for fuel monitors included something to the effect of being “GPS ready” or “GPS capable”. What, I wondered, did GPS have to do with fuel flow? So I looked into it a little further, and apparently what GPS does for fuel monitors is provide estimated fuel remaining at destination. I thought that was why we flight planned in the first place—so we would know estimated fuel remaining on arrival, and I thought that was why we kept a flight log enroute, so we could see how that estimate was holding up? If the trend was seriously negative, we could do something about it before we got to dry mouth time. There’s nothing wrong with having a running estimate of fuel remaining at destination, but it told me that if pilots were willing to spend extra money for it, it was because they didn’t have a very good idea otherwise. Any kind of a decent flight plan, one that includes winds aloft forecasts along the route of flight, is going to be better than a simple GPS estimate based on current groundspeed and the assumption that it will stay constant for the remainder of the flight. Now, a flight management computer, or any kind of computerized flight log with position input is the best of both worlds, but I don’t see where having a simple fuel remaining estimate based on current winds tells you a whole lot. It would be pretty disconcerting, for instance, to see that number start out big, and then watch it get smaller and smaller as the headwinds increased, or the tailwinds decreased, along the route of flight. Some information isn’t always a good thing.

I also know that, as a practical matter, most reciprocating aircraft have their tanks topped off after every flight. And I know that topping off the tanks is not always done just to simplify flight planning or to pay homage to the “You never have too much fuel unless you’re on fire” rule. Avgas and water don’t mix, the water settles in the low points and causes all kinds of problems, and full tanks minimize condensation. Also, most general aviation fuel tanks are rubber bladders and fuel keeps them from drying out. So topped off fuel tanks may be a practical fact of life for most general aviation pilots. But that doesn’t eliminate the need for good flight planning and for maintaining an enroute log, and it certainly doesn’t eliminate the question, “How much is enough”?

We know what the regs say (FAR 91.151 and FAR 91.167), but we don’t worry about them too much because, again, the tanks are always full and we don’t try to stretch our range, so we know we will always have enough, if we are VFR, to fly to our destination plus 30 minutes of fuel at normal cruise, 45 at night, and if we filed IFR we need that plus enough to “complete the flight” to the destination—that means descend, approach, and land—and after that fly to an alternate, as required. Assuming you do have only these minimum amounts of reserve fuel, what does that do for you?

VFR, not very much: 30 minutes of fuel is barely enough to see on the gauge, and who knows how much of that is water, gunk, or even usable as you turn from base to final? Forty five minutes at night isn’t much better. I’m not a big fan of VFR at night anyway, it’s hard to see the clouds, and pilotage is a whole lot more difficult at night—better hope that Garmin doesn’t take the night off. So day or night, these reserves are minimal and don’t allow for any contingencies, which is what the reserves are for.

The fuel requirement for IFR is a little better: enough fuel to actually fly to your destination, shoot an approach, do a missed approach, climb back to a safe cruising altitude, proceed to your alternate, land and still have 45 minutes of fuel at normal cruising speed to use, presumably, for your approach and landing there. (You don’t always have to have an alternate, but you’re nuts not to.) That’s quite a bit more fuel, but more to the point, there is a real purpose to it: fly to your destination and land; if unable, fly to your alternate and land there. I don’t really know where the FAA came up with “45 minutes at normal cruising speed”, but these rules go back a long long ways, and they provide the starting point for that question, “How much is enough?”

The NBAA (National Business Aviation Association) has established a minimum fuel profile that is frequently cited in ads and articles on business aircraft: “Range based on NBAA IFR reserves,” is a typical footnote, for instance. The NBAA profile includes fuel for a missed approach, climb to 5000 feet, hold for five minutes, climb at best rate of climb to the optimum altitude to fly 200 nm to an alternate at long range cruise, descend to sea level and land with 45 minutes of fuel. In other words, it flight plans fairly accurately and realistically a typical missed approach at the destination, diversion to the alternate, descent and landing. It is very useful for comparing maximum range of one aircraft to another, and it is useful as a model for realistic flight planning, but it doesn’t really address the issue of how much is enough when you finally do land; it assumes that, ultimately, the FAR 91.167 minimums are adequate. So it’s great for comparing range for one aircraft to another, but not so great at telling you whether you would actually want to fly that aircraft that far.

There are two other interesting lessons implied by this profile, one is that there is no fuel allotted to try the approach again—it assumes you try once and if you miss you go as directly as possible to your alternate and you land there—and it assumes you always will have an alternate. My view on this, discussed in some detail in a previous post, “The Other Part of Flight Planning,” January 2010, is that that is exactly what you should always do: shoot one approach, if unable to land divert to an alternate, one with a precision approach and weather forecast well above minimums, and land there. Too many general aviation accidents occur on the second and third try at the destination; professionals just don’t fly that way and professionals don’t have those kinds of accidents.

So we still haven’t completely answered the question, “Is 45 minutes of fuel based on normal cruise fuel flow adequate or not?” and the only way, I think, that question can be answered is to ask, “What is that reserve fuel for?” The first thing it is for, the most basic, is to make sure there is always “some” fuel remaining at the end. That means, we want there to be enough fuel in the tanks that the needles aren’t resting on the bottom of the gauge—we want a little day light there. Again, who knows what’s in the bottom of those tanks? We want some fuel in the tanks when we finally land, and we want to know for sure that it is fuel and not water, sludge, rubber bits, dirt or anything else that won’t burn. (ATA had an engine flame out on a 1011 just before takeoff. Further investigation revealed that the fuel filter was clogged with bits of cloth and foam padding—a mechanic, working inside the fuel tank, had left his cushion behind. Probably not going to happen to Cessna 152, but strange things do find their way into fuel tanks.)

Let’s look at both 30 and 45 minutes of fuel at “normal cruising speed”, whatever that means. I happen to have five different pilot operating handbooks at home, and the only one that lists a “normal cruising speed” is the Piper Turbo Twin Comanche and that is also its highest power setting (other than max continuous). That’s okay if Piper wants to call it that, but it doesn’t necessarily make it “normal.” (“Old” Piper, that is. New Piper, with the Malibu in any case, another one of the manuals I happen to have on hand, goes back to calling it High Speed Cruise.) So, what is normal? The one your instructor told you to always use? The one that gives you a nice round fuel flow number like 10 gph? The one you happened to flight plan for that day? As far as I’m concerned they are all normal, so take your pick: the higher the power setting, the more fuel will be required. What about the airplane that normally burns 10 gph? Thirty minutes of fuel would be five gallons, typically split into two tanks: two and a half gallons per tank. That might get the needles off the peg, but not by much. Forty five minutes is only a little better, three and three quarters gallons per tank.

If we look at the Piper Turbo Twin Comanche performance charts, Normal Cruise is supposed to be 22.6 gph. Thirty minutes of fuel would be 11.3 gallons, 5 2/3 gallons per tank. Forty five minutes would be almost 17 gallons (16.95) or about 8 ½ gallons per tank. I can probably see that on the gauge, but I wouldn’t like what I saw. And remember these numbers come from using the highest normal power setting; economy or long range power settings would yield even less.

So I think we can safely say that the FAR minimums are not enough. How much more would we like to have, and, again, for what reason? First, we have to agree that the professional way of operating a flight, if we can call it that, is assumed here, or else we’re back to, “You can never have too much fuel.” Let me explain: If we agree that the way to flight plan and operate a flight is to always have a good alternate, and to proceed to that alternate after one try at the destination, then the amount of fuel we would like to have above and beyond that necessary just to fly that profile is a legitimate and serious question. If we don’t agree with that premise, if we want to have the option to try the same approach again, hoping for better weather, or the chance to try to fly the approach better and not have to go around the next time, or to try a different approach, or to hold for awhile hoping the weather improves, or if none of that works, to try the nearest airport to the destination and if we can’t get in there either try another one, then we’re back to taking as much fuel as we can and hoping that will be enough. So if you don’t agree with the basic premise, you can stop reading right now because the rest is irrelevant to you. And good luck.

But let’s assume you have flight planned carefully and you know exactly how much fuel it should take to go to your destination, shoot an approach, do a missed approach, proceed to your alternate, shoot an approach there and land with 45 minutes of fuel remaining. Is that enough, or do you want a margin above that, and for what reason? Well, I think it is obvious that you want more that just enough, if for no other reason that these are flight planned numbers, not real world. In the real world, fuel burns are often higher than book values and airspeeds slower. In the real world you don’t always get the routing you requested or the altitude, the winds aloft are sometimes less favorable than forecast, thunderstorms and icing conditions force detours, and congestion results in vectoring and holding. You don’t often get all of these adverse factors on every flight, but almost all flights will be affected by one or more of these factors, and they all require more fuel. So again, how much?

There are, I think, three ways to look at this. The first is to try to come up with a reasonable and conservative number to account for several, but not all, possible adverse factors. (If you have a really bad day and all of these negatives combine, your enroute log will say to you, “This isn’t going well. You need to land now.”) The second way is to increase the minimum fuel by a given percentage, and the third way is to increase the fuel in terms of additional flying time. All three work, and I’m not sure any one is better or worse than the others; for sure the first one is the most complicated, but it is possibly also the most accurate. Each will be more or less conservative depending on the assumptions made: How many adverse factors do I expect, and what will be their effect?

The airlines, under FAR 121, are required to increase their enroute fuel by 10% when operating internationally. That can be a bunch of fuel for a long flight. (The airlines have found a way around this in the form of a re-release flight plan, which is way too complicated to get into here, but it shows the limitation of the simple percentage method: too much extra fuel on long flights, not enough on short ones.) For the Piper Turbo Twin Comanche, a long flight might require 80 gallons of fuel from takeoff to destination. Ten per cent would mean adding another eight gallons, or about 30 minutes, plus or minus a few minutes depending on the power setting. That seems pretty reasonable to me: 30 minutes of deviating, of groundspeeds slower than flight planned, of getting vectored around, of having to fly lower or higher than desired to stay out of ice, or some combination of all of the above, sounds pretty reasonable to me. (Remember, this is fuel above the 45 minutes required by regulation.) If you want more, or experience shows that that still leaves too many sweaty palm situations, increase it. But have a number, keep track of it enroute, keep records and review them to see how your number is working out, and amend that number as real world experience dictates.

Why do we do this, if, as is usually the case, the aircraft is already full of fuel? What’s the point? You get the fuel you get, some days just a little more than what you need and some days a lot more, but what’s the point of figuring a specific fuel load for that flight that day if the tanks are already full? I think there are several good reasons, but perhaps the best is that you may find out that, even with full tanks, you don’t have enough fuel. That is, what looks alright based on rules of thumb and past experience isn’t enough when you take a more accurate and complete look at it: takeoff and climb, enroute, descent, approach, miss, climb, cruise to alternate, descend again, shoot another approach, land, add 45 minutes of fuel to that (FAR 91.167) and then your own personal number on top of that. And if full tanks won’t let do all of that, then a safe outcome is no longer guaranteed. It may seem like a lot of fuel, and most of the time, when everything goes pretty much as expected and you make a routine arrival and landing at your destination, it probably is, but sooner or later it’s not going to be.

So that’s good reason number one. Good reason number two is that it forces you to have a plan, one that you have assured yourself you have enough fuel for, and one that virtually guarantees a safe outcome. Any fuel above and beyond that required for the plan carries a weight penalty, but at least you know what that weight is. Good reason number three is that it might get you to thinking about ways to not top off the aircraft after every flight without encountering condensation problems or bladder drying. That’s a subject for another time, but suffice it to say that a regularly flown airplane, stored in a heated hangar, is a good candidate for fueling as required prior to flight.

My chief pilot was right: you always want to land with some fuel in the tanks. But topping the tanks off and relying on rules of thumb won’t guarantee that; the only way to guarantee that is to have a plan and stick to it. And fires have nothing to do with it.

AirVenture 2010

AirVenture 2010—“Oshkosh”—is less than two weeks away. I will be there from Opening Day (Monday, 25 July), through the week, leaving Sunday (1 August). I’m leaving on Sunday because I learned the last time I was there for a full week that Sunday is really “get away day”, with not much going on and, if you do stay for it, a bit of a let down after a full week of aviation activities.) I will be doing Authors’ Corner, which is a chance to meet people and do book signings, on Monday from 1030 to 1130 and on Saturday from 1130 to 1230. I will also be giving a presentation on Thursday at 4 pm, just after the air show, in the Dake Pavilion, on the subject of aviation blogs. If you’re going to Oshkosh on any of those days, I hope you’ll stop by and introduce yourself as a blog follower. (The full title of my presentation is “Aviation Blogs: Another Way to Stay Connected.” Which it is. But the best way to stay connected is to just walk up and say “Hi”.)

World Cup

I don’t know why exactly, and it doesn’t really matter, but for the first time, it seems to me, there is a lot of interest in the US in the World Cup soccer competition. My own interest in it goes back to 1990 when it was held in Italy and ATA, then American Trans Air, had several contracts with European travel companies to take fans to and from Italy for the tournament. As a very junior L-1011 copilot, I ended up doing a lot of those trips, mostly to and from Ireland and England, because the more senior pilots generally preferred shorter, domestic trips and as the new guy, I got what was left. But it was fine with me—I loved the international flying and I loved being in Europe. You couldn’t help but get caught up in the enthusiasm and excitement, with every pub in England and Ireland full of fans watching on TV who couldn’t go, and every village square in northern Europe full of fans drinking hefeweisen, the traditional summer beer there, and watching the matches on big outdoor screens. Italy itself was decorated from boot top to toe with banners and billboards, the entire country decked out for the event. It was one of the best summers of flying for me at ATA, and one with many great memories.

One memory in particular stands out. I was flying with Dan Drummond, check airman and captain, and at this point in my career, something of a god (see “Step On It", April 2010). We were in Dublin, having dropped off a load of Irish fans in Palermo, and had set off, along with two flight attendants, on foot from our hotel to the nearest pub to watch Ireland play England, a rivalry that makes the Red Sox-Yankees rivalry look gentlemanly. We were anxious to get there, so we talked the two flight attendants into cutting across a pasture. They were dressed in I don’t really know what, but whatever it was left their feet and ankles exposed. We had long pants and socks on. (There is a reason I’m describing these details.) We got to the pub and managed to get a table with a view of the screen, got our beers, and before we had taken even a couple of sips, the flight attendants starting scratching and complaining about how much their feet and ankles itched and stung. And they wouldn’t stop, just more and more complaining, and they pretty quickly figured out that there had to have been something in that field we cut across, something not good, at which point most of the bitching and moaning became aimed at us. We asked locals what it might be and they said, “Oh, nettles, you know. Stinging nettles. Absolutely full of the stuff, up to the kneecaps.” It lasted for hours and I think the only reason they let us live is because we were their ride home.

There is another, happier memory of that match as well. Ireland scored the first goal, and as you can imagine, the place went crazy. The Irish take their kids to the pubs with them, at least they do on the weekends and for big events, it’s a very social, community place, and pretty much just let the kids run around having their own kind of fun. In the midst of this craziness, I saw a little kid, 3 or 4 years old, running to his dad to join in the celebration. Someone else, an uncle maybe, caught him as he ran by, picked him up, and flung him, some 10 or 12 feet, to his dad. The story does have a happy ending, the dad catching the kid and the kid screaming with delight.

Soccer is now a very big sport in the US, of course, with “soccer moms” almost as common a phrase as “golf widow.” But that is a fairly recent phenomenon. My generation, the Baby Boomer generation, generally didn’t know anything about soccer, didn’t even know what season it was played in, but it didn’t matter because we already had a year’s worth of sports, baseball, football, and basketball. As an army brat living in Germany in the late ‘50s’ though, we were introduced to soccer at school. I’m sure it was part of the Army’s continuing effort to improve German-American relations, an uphill struggle, and not just because this was only 10 years after the war, but also because we lived almost completely separate lives, with American living quarters built just for military families, US schools, US sports, US snack bars and movies and bowling alleys and so on. And it is still pretty much that way. If you are US military and you want to get to know the locals and their culture, you have to make an effort. You can spend three years in Germany and never leave America if you want to. So the soccer program was part of the effort to get us kids familiar with the national sport of Germany.

We were taught the basics of soccer, positions, rules, simple plays, and played some, not well of course, but it was all great fun because we were 10 years old and we were outdoors. But it didn’t really catch on with us. When the weather was warm we would always play either baseball or football, not soccer. Didn’t even think about it. And when my brothers and I got back to the States, no one had even heard of soccer. And I’m still not a big fan. Which doesn’t mean I don’t think it’s a legitimately exciting sport, it just means it’s a sport I don’t follow and don’t relate to much.

So why is it now so popular? I suspect it has to do with a generation of kids growing up not with soccer as a side sport, or an afterthought, but as a primary sport, the sport they play when the weather is warm. And that’s fine. For me, though, the part of soccer I miss is sitting outdoors with a hefeweisen watching it with a bunch of other fans on the big screen, and most of all, I miss being the guy who flew the airplane that got them there.

Well Done

1LT D (soon to be CPT D), arriving stateside, Pope Air Base, Ft. Bragg, NC.(For more on Lt. D, refer back to the post titled “Lt. D”, February 2010.)

I’ve flown in and out of Pope many times. It’s great to see it from another point of view.

To Lt. D and all the members of his platoon, well done and welcome home.

Step On It

A recent accident here in the San Francisco Bay Area has me thinking about engine failures for multiengine aircraft. The accident occurred on February 17th (2010) on takeoff from Palo Alto airport. All three occupants were killed, all senior executives of the high performance electric powered Tesla sports car company, enroute to a company facility in southern California. The aircraft was a normally aspirated Cessna 310R, and the pilot was a very experienced general aviation pilot with a reputation for good judgment and proficiency.

The aircraft took off on runway 31 in conditions of very limited visibility—heavy fog—reached about 50 feet in altitude and, instead of continuing to climb straight ahead to 400 feet followed by a turn to 060, the standard instrument departure for this runway which puts the aircraft out over the South Bay, it drifted to the left, clipping a high voltage electrical tower with one wing, crashing, presumably completely out of control, into a nearby neighborhood. Fortunately, no one on the ground was hurt.

No one likes to second guess pilots following tragic accidents, and I won’t. I didn’t help, I’m sure, that the Palo Alto airport is only 2440 feet long; it didn’t help at all, I know, that the visibility was so restricted. Nonetheless, not just this pilot, but many pilots have operated safely out of this airport, in conditions like this, for a long time. But something went wrong this time.

The NTSB is still studying this accident and it will probably be several more months before anything official is released. But everything points to an engine failure at takeoff, followed by a failure to maintain directional control. If the pilot had been able to continue straight ahead, even if he couldn’t gain altitude, the area directly ahead was free of obstacles for several miles, versus the one mile or so to the tower and neighborhood. The problem is, maintaining directional control directly after takeoff at a very slow airspeed, with no outside visual references, is an extraordinarily hard thing to do. This wasn’t a bad pilot; this was a pilot who got caught by a worst case scenario of events.

So the accident got me thinking about engine failures in general, both in general aviation aircraft (I used to do quite a bit of multiengine instruction) and, of course, in corporate and airline equipment, V1 cut after V1 cut. Practice, and being ready—on every single takeoff—for an engine failure are key. But something that I didn’t learned until I got into jet training, that may or may not be common in general aviation training—I know I didn’t teach it in my multiengine instruction—may be helpful here.

The most common phrase you hear in multiengine training is, “Dead foot, dead engine,” and that is certainly a good rule to help in identifying the failed engine. But it assumes you already have things pretty much under control. A lot of things have to happen, and happen right, before you can get to “Dead foot, dead engine”; specifically, it doesn’t tell you which rudder pedal to push on.

I remember giving a pilot new to international operations training in MNPS—Minimum Navigational Performance Standards, the document that covers North Atlantic track operations between North America and Europe. I was, in turn, being observed by another captain and check airmen, Dan Drummond, a very experienced and capable pilot who did some of my own MNPS training when I started at ATA. Dan and I became good friends over the years, and were very respectful of each other’s ability, but Dan took his job seriously, and didn’t hesitate to critique my performance if he felt it necessary. On this particular occasion, he felt I was perhaps wasting some valuable instruction time enroute after I had decided the poor guy needed a little break from all the questions and “what ifs.” So Dan said, “Look, let’s talk about what we would do if we had an engine failure right here, right now.” So the copilot starting thinking, and wasn’t quite sure where the question was going, was it about identifying and shutting down an engine enroute, or notifying ATC on HF, or other aircraft in the vicinity on VHF air-to-air, or is this about drift down altitudes and diversions off the tracks, he just didn’t know where to start, and understandably: if that were to happen, it is a little hard to know what to do first, which is why Dan was posing the question. After several tries, a little mixed up, Dan asked me, and I don’t remember exactly what I said, but something like, “Well, the first priority is aircraft control, then a turn off track and a declaration of emergency to other aircraft on the track, then the engine failure checklist.” Dan said, “Right, but what does aircraft control mean? It’s on the autopilot. It’s under control isn’t it?” I said, “Of sorts, but the autopilot has no rudder control at cruise, so it’s going to try to do it all with aileron.” And Dan said, “Exactly. So the first thing we’re going to do, the very first thing, is we are going to put some rudder in.”

And that is the case in every engine failure involving multiengine aircraft (except for centerline thrust aircraft like the Cessna Skymaster), regardless of phase of flight or flight conditions. The problem is, when an engine fails, the aircraft doesn't just yaw, it also rolls. The natural reaction, ingrained from day one of flight training, straight and level flight, is to correct the roll with aileron, just like the autopilot would. And that reaction is going to happen every single time, there is just no way to avoid it. Then the second reaction is going to be, “No, not aileron, I need rudder.” But which one? I sure don’t want to make the situation worse and push on wrong rudder. Again, how do we get to “Dead foot, dead engine”?

The long way to figure it out is to think it through: I have lost an engine, I don’t know which one yet, but the aircraft wants to roll to the right and I am countering that by rolling left; what I really want is not a roll to the left but a yaw to the left: left rudder. What’s the short way to know which rudder to step? Remember a very simple rule: “Step on the low side.” (The low side of the control yoke, that is.) The aircraft wants to roll right. You counter by rolling left. That puts the control yoke down to the left. “Step on the low side” tells you to use left rudder instead.

What happens when you do that? The first thing that happens is that the rudder is much more powerful in controlling the yaw caused by the operating engine than the aileron is. In fact, even at a very slow airspeed and at full power on one side and wind milling on the other, the rudder is powerful enough to control the yaw completely, resulting in straight flight (as slow as VMC, minimum control speed). Which means the aileron is no longer needed and the aircraft will now roll into the operating engine. Instinctively you take the aileron input out to return to level flight, and when the control yoke is back to level, there will no longer be a low side, and you will know that you have the correct amount of rudder for those conditions—for that airspeed and that amount of asymmetrical power. Not enough rudder, one side will still be low, step on it a little more to get the yoke level. Too much, and the other side will be low, meaning, step on that side. (Actually, it means letting up a little on the rudder you are pushing, but since the two are connected that is the same as pushing on the low side.) The secret is to keep the yoke level, and the trick to doing that is to apply rudder to the side that is low. (Actually, up to five degrees of bank into the operating engine is allowed on check rides, and a little bit of bank is beneficial. But only a little bit—anything beyond five degrees adds drag.)

The only tricky part here is equating releasing pressure on the high side as being the same as adding pressure—stepping on it—on the low side. Going through a typical engine out scenario may help explain and clarify that. Any engine out scenario will do, the procedure is always the same, but let’s take the typical training scenario, an engine failure after takeoff. You have done everything right so far, acting instinctively to counter the roll, you saw which side of the control yoke was low, you “stepped on that side,” on that rudder, taking the aileron input out as you did, until the yoke was level. You are now flying straight but are probably barely climbing, because you still have the gear extended and haven’t secured the dead engine and feathered it’s prop, so you raise the gear and (this is where “Dead foot, dead engine” comes into play), you slowly retard the throttle on the inoperative engine, the dead engine, you pull the prop control back to feather, and you pull the mixture back to cut off for that engine. As you slowly start to climb again, your focus is 100% on wings level flight and rate of climb—gaining altitude. If you had airspeed above best single engine rate of climb speed (Vyse), it has been traded off for climb. If you are below Vyse, you need to accelerate to that speed but only if you can do so without descending. In every case you are nursing the aircraft along on one engine at full power, full or nearly full rudder against the yaw and, once cleaned up and established at Vyse, you are adjusting pitch ever so slightly to maintain that speed and climb at the maximum rate achievable. And let’s say you do all that, and finally you get to a safe level off altitude where you can start to accelerate to a single engine cruise speed, perhaps even reduce the power a little from full throttle, try to sort things out and consider your return. As you slowly pitch over and accelerate, the aircraft wants to roll again: the increased airspeed makes the rudder more effective, the extra rudder effectiveness causes the aircraft to yaw which causes it to roll and you have again, instinctively, countered that with opposite aileron. The result is that as you accelerate, one side of the yoke starts to drop again. Again, step on the low side. But you aren’t actually stepping on the low side, you’re already stepping, or holding rudder, on the other side, but you are now holding too much. You need to release some of that pressure; still, if both feet are on the pedals, the foot on the low side will be the one going forward, and the one on the high side will be coming back.

The same thing happens when you reduce power. With less asymmetric power, less rudder is needed and pressure should be released. Anytime there is a change in power or airspeed, the amount of rudder required will change. But the rule is always the same: If the control yoke is not level, the foot on the low side should be going forward—“stepping on it”—and the foot on the high side should be coming back.

There is a useful corollary to this rule, and that is the “Step on the bug” rule. This rule assumes you have a heading bug on your directional gyro, and that it has been set to the desired heading, which would be runway heading on takeoff. If you think about it, what happens to the heading bug if you drift to one side or the other of that desired heading? It swings in the opposite direction. For example, if you are taking off on runway 31, and you slowly turn to the left, the compass rose will turn clockwise as you turn through 300, 290, 280, etc, taking the heading bug with it. If you are turning left and want to correct right, you want to turn to the right. Easy enough to think through right here, sitting at your desk in front of your computer, but what about right after takeoff into IMC? Look at the heading bug, then step on it: put enough rudder pressure on the side the bug is on to cause the bug to turn back to the center. When it is back in the center, on the desired heading, release enough pressure to keep it there.

I don’t know if these memory aids would have helped this pilot or not. I don’t even know for sure what went wrong. But I do hope they help you.