Emergency!

It's a beautiful day for flying. The winds are light, the sky is clear, and the temperature is perfect. It's the sort of day where you'd almost feel guilty if you didn't take advantage of the opportunity, since the beginning of fall means days like this are numbered.

It's just a short hop from Wilkes-Barre/Scranton over to Newark. Not even half an hour in the air at 270 knots, and less than an hour from gate to gate. Nonetheless, those few dozen minutes take you through some magnificent scenery, from the Pocono Mountains and the "tricky triangle" of the Pocono Raceway, over the Delaware Water Gap that runs through the Worthington State Forest and marks the border between Pennsylvania and New Jersey, over thick woods dotted with lakes carved out by glaciers 20,000 years ago, to farmland and then cities packed more and more densely before the trip ends just on the other side of the Hudson from the magnificent skyline. What could go wrong?

Well, just like any flight, nothing will probably go wrong, but something always can. And in this case, something did.

We're about 10 miles northwest of the Boonton Reservoir. It's easy to spot from the air, as it has a small island in the middle of it; in fact, it's so easy to spot it's used as a visual checkpoint:

Boonton Reservoir is the lake marked with a flag at the upper left. Newark is the big airport near the bottom right.

How do I know this? Because I'm keeping the general picture in my mind of where we are as the flight progresses. That's nothing unusual; in fact, that's exactly what you're supposed to be doing!

We've already started our descent and begun the pre-landing preparations. Everything is going just as it has on almost all of the hundreds and hundreds of flights I've done before. And then a blinking red light comes...

SMOKE

We have dozens of yellow caution lights for all sorts of minor issues, from the parking brake being set to hydraulic systems to any of the multitude of power sources. These cause a yellow flashing light to come on. We have only a handful of red ones: the ones that are REALLY serious. This was one of the red ones.

This one's job was to tell us that there might be a fire in the cargo compartment. What are we going to do about it?

The same thing you should do every minute of every flight: fly the airplane.

On this particular leg, I was the Pilot Not Flying and the Captain was the Pilot Flying. He did exactly what needed to be done: he flew the airplane while we dealt with the problem. What does "dealing with the problem" mean? The same thing it should mean for you, and the same thing you should have been trained for (and we are trained for every six months):

Don't just do something--sit there!

This is an old aviation adage that has a world of wisdom wrapped up in it. It doesn't mean do nothing, it means do the right thing in the right way at the right time. This is an easy 3-step process:

1. Fly the airplane
2. Keep calm
3. Run your procedures

From the sectional excerpt above, you can see that we were close to both Essex County and Morristown Municipal. Both of them were suitable for landing. We continued past them and on to Newark. Why?

Because we were busy doing those three steps. The Captain was flying the airplane, we were both calm, and I was running the checklist for a smoke warning annunciator. To make a sudden, drastic change in destination would require a whole new plan of action; something probably not best done while in the middle of trying to determine if the back of the aircraft is on fire. One thing at a time: the right thing in the right way at the right time.

While I'm just beginning the checklist, New York Approach spits out in their rapid-fire way a descent, a heading, and a frequency change. Since I was busy managing the checklist, I simply repeated the frequency, ignored the rest, and checked in with the new controller in a calm voice,

"New York, [Flight Number] declaring an emergency. We've had a smoke warning light come on. No further assistance required at this time."

Basically, in a few short sentences, I told ATC--who are a vital part of the team in this--that we have a problem, that it might be a serious one, we're coming to Newark and we need to do it in the most direct way, and we're busy dealing with it so keep the chatter and instructions to a minimum while we handle it.

And that's exactly what they did and we did. They gave us a simple heading that pointed us straight to the airport, gave us an altitude that would set us up on a downwind leg for the runway they would have cleared and waiting for us, and asked very few questions except for the standard souls on board and fuel remaining ones.

In the meantime, I was running through the checklist, informing the flight attendant of the situation and asking her to see whether there actually was smoke coming from the cargo compartment or not, getting the final before landing items done, and so on. After all, this sort of thing has happened to me many times before--except all the other times were in the simulator.

After a couple of minutes, the flight attendant reported that there was no sign of anything unusual. It was likely a false alarm, but we continued to handle the situation exactly the same. Fly the airplane, keep calm, and carry on.

After landing, a half dozen fire trucks were waiting for us on the taxiway we'd be likely to turn off. Notice in my initial call-up above that I never asked for them. I didn't need to: ATC is highly trained too and smart enough to know that where there's smoke, there's fire. All I had to do was tell them our situation and let them do the job of getting the resources supplied.

As we taxied off the runway, I thanked ATC for their help and switched to the frequency the fire trucks use. They made a pass around the plane and saw nothing usual either. They scanned the cargo compartment with their thermal cameras and verified that there was no fire. It was just a bad sensor after all.

Any time a big red flashing light goes off in the cockpit, it's easy to declare an emergency. But what about when things are seemingly more minor? In the next post, I'll get into a bit more about what constitutes an "emergency". See you next Wednesday!


Like Larry the Flying Guy on Facebook:

Follow @Lairspeed

The author is an airline pilot, flight instructor, and adjunct college professor teaching aviation ground schools. He holds an ATP certificate with a DHC-8 type rating, as well as CFI, CFII, MEI, AGI, and IGI certificates, and is a FAASafety Team representative and Master-level participant in the FAA's WINGS program. He is on Facebook as Larry the Flying Guy, has a Larry the Flying Guy YouTube channel, and is on Twitter as @Lairspeed.

It takes hours of work to bring each Keyboard & Rudder post to you. If you've found it useful, please consider making an easy one-time or recurring donation via PayPal in any amount you choose.

How to crush something without touching it

What if I told you I can crush a water bottle without touching it? You probably wouldn't believe me, would you? Of course you wouldn't. How can something get crushed without having something doing the crushing?

But I can. I have proof:

Crushed it!

I did not touch this water bottle for at least 30 minutes before I took this picture, and when I put it in that pouch, it was a normal-looking, quite round bottle of water.

So what happened? And how did I crush it without touching it? Well, to be technically correct, I personally didn't crush it; I just set up the conditions for something else to do the actual crushing.)

The thing that did the actual squishing was atmospheric pressure: that invisible ocean of atmosphere that surrounds us. You can't see it, you can't hold it in your hand, and you don't even notice that it is pushing down on you with the weight of an entire bowling ball on every square inch of your body. That thing.

You don't usually notice it at all, since our bodies basically push out against it with the same 14.7 pounds per square inch (psi) of pressure that it pushes in on us with. We're usually in equilibrium with it, so we take no notice of it. Kind of like in-laws who live on the other side of the country: they're there, but we don't notice them.

If the bottle was perfectly fine half an hour ago, why isn't it fine in this picture? Because of something we did in the time in between: we descended from our cruising altitude and landed.

When we were up at 24,000 feet, the pressure inside the cabin was roughly the same as it would be if we were only at 8,000 feet. Think of climbing a few thousand feet up a mountain outside Denver: that's about how thin the air inside the cabin would have been.

By the time we landed, the pressure inside the cabin was a mere 313 feet above sea level, which is the elevation of Washington-Dulles International Airport. So in the meantime, the effective change in air pressure was the same as climbing 7,700 feet down a mountain. There's a lot more air down here. That means a lot more air to push on the bottle.

At 8,000 feet, the atmosphere was pushing on the bottle with a weight of 10.9 pounds per square inch. Because of that, when I drank the last of the water and put the cap back on, the air pressure inside the bottle was 10.9 psi, the bottle was perfectly round, and everyone was happy.

However, by the time we landed, the air pressure was up to 14.6 psi. More air = more pressure on the bottle. However, since I didn't touch the bottle, the air pressure inside it was still only 10.9 psi. Since there was more pressure outside than inside, the bottle collapsed. By opening the cap and letting air in, the bottle would "inflate" back to its round shape, since the pressure inside the bottle and outside would both be 14.6 psi.

If things get crushed as you descend, why wouldn't the bottle start bulging as we're climbing up? After all, the pressure inside the bottle would be 14.7 psi if it were filled at sea level, and back to 10.9 at 8,000 feet. It should do the opposite in the climb as it did in the descent, right?

Right. It does just that, actually. However, the bottle tends to be filled with water and not air on the way up, making less room for the more compressible air. Also, the bottle stretching outward is much less outwardly visible than its collapsing inward. Nonetheless, it is bulging. It's a lot easier to see in the seal on this Pringles can, which was bulging in cruise just before I opened it:

That seal is just bursting with flavor at a cabin altitude of about 6,000 feet.

This expansion and contraction cycle is why your ears pop twice during a flight. On the way up, the air on the inside of your eardrum is trying to push it outward. On the way back down, the air on the outside of it pushes it inward.

Imagine if we could hook up some gears and a meter to the outside of the water bottle. The gears could drive some sort of indicator that shows us how much air pressure is around us based on how much the bottle bulges or gets crushed. That would be a neat way to indirectly measure how high we are.

Don't rush to the patent office just yet, as someone already came up with this idea a long time ago. (Long before airplanes, even. Mark Twain mentions a device using a similar concept in his book A Tramp Abroad, which was written way back in 1880, and the idea wasn't new even then.) There already is something in the airplane that uses this expansion and contraction of trapped air inside a container and puts it to good use. A very vital thing, actually. It's called the altimeter.

Figure 7-2 from the Pilot's Handbook of Aeronautical Knowledge. You can download the entire book for free from the FAA's website. Your tax dollars at work.

That thing labeled "Aneroid wafers" that looks like a stack of discs or an accordion's bellows operates on the same general principle as the water bottle. As the wafers bulge outward, they're connected to some gears that are connected to the dial on the altimeter's face and make the hands indicate the altitude winding upward. As they shrink, the hands start going in the opposite direction. If the aneroid wafers are not bulging or shrinking, you're in level flight.

In the altimeter's case, it's connected to an air pressure source outside the airplane (the static port) so it isn't measuring the air pressure inside the cabin like the water bottle was, but the principle is exactly the same.

When you're learning to fly, everything in aviation seems to run off of two sources of energy: money and magic. While it has always been the case that flying isn't cheap, I think it's an excellent investment because of the magic it brings along with it. Your instruments, however, don't run on magic. They actually run on simple principles of physics that are harnessed in a way that sometimes looks like magic. And it can turn you into a magician who is able to crush things just by looking at them.

See you next Wednesday!

Like Larry the Flying Guy on Facebook:

Follow @Lairspeed

The author is an airline pilot, flight instructor, and adjunct college professor teaching aviation ground schools. He holds an ATP certificate with a DHC-8 type rating, as well as CFI, CFII, MEI, AGI, and IGI certificates, and is a FAASafety Team representative and Master-level participant in the FAA's WINGS program. He is on Facebook as Larry the Flying Guy, has a Larry the Flying Guy YouTube channel, and is on Twitter as @Lairspeed.

It takes hours of work to bring each Keyboard & Rudder post to you. If you've found it useful, please consider making an easy one-time or recurring donation via PayPal in any amount you choose.

What you can't see can hurt you: Avoiding wake turbulence

I recently came across a very nice picture of wingtip vortices. (Unfortunately, it was passed to me without any information on who took it or where. If you know, please let me know so I can give them the credit they deserve.)

With the exception of some NASA tests with equipment designed to help make them visible, these are usually invisible. In the picture below, you get a nice view of what these vortices do to the air, and where wake turbulence comes from. (Throughout this post, for simplicity's sake I'll refer to wingtip vortices and wake turbulence interchangeably.)

Notice the airport in the background.

These are behind every airplane that is creating lift, from a 747 to a 172. In fact, in your training you may have done a nice steep turn, and toward the end of it felt a bump seemingly out of nowhere. That was you doing such a good circle that you hit your own wake turbulence.

If they do this to a thin cloud layer, imagine what they'd do to you if your airplane was in that path. Well, the FAA has made sure you have a scary idea of what they could do, as they point out on pages 13-15 and 16:

"The vortices from larger aircraft pose problems to encountering aircraft. The wake of these aircraft can impose rolling moments exceeding the roll-control authority of the encountering aircraft. Also, the turbulence generated within the vortices can damage aircraft components and equipment if encountered at close range."

This is a very dry, boring way of saying that flying into them can flip your butt over and/or rip your wings off. As exciting as falling head over heels for wingtip vortices might sound, their behavior is fortunately very predictable, which means there's an easy way to avoid them.

Since they're part of the air mass, they move along with it. They also tend to sink. Since we usually try to land into the wind, this means they're coming toward you but sinking at the same time. Solution: just stay above the glidepath of the plane ahead that caused them and you'll avoid them.

I use this quite often when I'm flying the Dash-8. Although at 43,000 pounds it's not a particularly small airplane, it's a wee speck compared to the 767s, 747s, and A340s I've landed behind at Newark. In these cases, I intentionally fly half a dot high on the glideslope.

Notice I said half a dot high. This is on a two-dot glideslope indicator. If you have a five-dot indicator, this is less than two dots. The figure below shows a glideslope indicator that's as high as you need.

Don't use more than this; you don't need to stay extremely high to stay above wake turbulence. It's tempting to do so if you think along the lines of "better safe than sorry", but staying way too high will make the final stage of the approach unnecessarily difficult. If you're flying visually or you don't have a glideslope receiver, use the PAPI lights to help you out. All you need for them is 3 white and 1 red. Again, no more.

At 5 miles out, this is only about 100 feet high. As you get closer to the runway, that gets smaller and smaller. By a mile out (further out than you'd be turning base if you were flying a traffic pattern), this is well under 50 feet. The top part of the following diagram shows you what I mean:

Well, that's great if you're coming in to land, but what if you're taking off behind a monster?

In general, the bigger the wingtip vortices, the bigger the plane. This is actually good news, because the bigger the plane, the more runway it tends to use on takeoff. This means that you can probably lift off well ahead of them. However, that's not the full solution, as the chances are very, very good that they can outclimb you by a lot once their wheels do break the ground.

Now what? Remember that wingtip vortices have predictable behavior, and they move along with the air mass. That means if there's a crosswind, they will slide along the side of the runway. Once you're reached a safe altitude, turn a bit in order to keep them on one side of you. If the crosswind is from the right, the vortices will be moving from right to left over the runway. Just turn a bit to the right to keep them on your left and you'll remain clear. If there's a left crosswind, turn to the left.

Most towered fields where GA planes mix in with the big ones understand what it takes to keep the shiny side up under these circumstances. Not only will they not have a problem with you sidestepping, they will expect you to do it on your own. When they say, "Cessna 1234 cleared for takeoff runway 27, caution wake turbulence departing Boeing 737", they are alerting you of the possibility of encountering wingtip vortices AND giving you implicit permission to maneuver within reason to avoid them.

Although they may make for a pretty picture, wingtip vortices can make for an ugly encounter. By keeping this post's tools in your bag, you can look forward to years of smooth flying!

See you next Wednesday!

Like Larry the Flying Guy on Facebook:

Follow @Lairspeed

The author is an airline pilot, flight instructor, and adjunct college professor teaching aviation ground schools. He holds an ATP certificate with a DHC-8 type rating, as well as CFI, CFII, MEI, AGI, and IGI certificates, and is a FAASafety Team representative and Master-level participant in the FAA's WINGS program. He is on Facebook as Larry the Flying Guy, has a Larry the Flying Guy YouTube channel, and is on Twitter as @Lairspeed.

It takes hours of work to bring each Keyboard & Rudder post to you. If you've found it useful, please consider making an easy one-time or recurring donation via PayPal in any amount you choose.

NORDO because of DUMBO

Keyboard & Rudder has been as silent as your local NDB antenna for over a month. It's not dead: I was just brain dead.

In July, I was due for my annual simulator proficiency check, which meant a lot of studying and little time for writing. The summer flying season was in full swing, so I was up in the air working a lot. Also, in addition to the book I've been working on for a while, I started doing research for a new book at the same time. This has taken even more of the limited writing time available.

I'm extremely excited about the new book, because if it comes out the way I would like it to, it may be another piece of the puzzle in changing the old "this is the way we've always done it" way of flight training that is one reason so few people complete flight training and turning it into a "we have all these tools nowadays, so let's start using them to make flying fun" approach. Sadly, one of the few places I've seen this attitude toward flight training is at Redbird. My hat is off to them for doing such a good job shaking things up!

This new book is particularly time consuming, since instead of simply writing words and pontificating like an academic, I'm spending hours and hours practicing what I preach in it. It is not just about learning to fly but about learning to learn and how one achieves mastery. I'm taking ideas from Malcom Gladwell's Outliers: The Story of Success, Matthew Syed's Bounce, Joshua Waitzkin's The Art of Learning, Tim Ferriss's The 4-Hour Chef, mixing in piles of modern research on learning and skill acquisition, combining it with my own experience as a flight instructor (and former student pilot once, too!), throwing in a dash of spices from sources as conventional as desktop flight simulators to the unconventional like lifehacking apps such as HabitRPG, and blending it all up to make learning to fly faster and better.

When it's finally finished, this will definitely not be the FAA's FOI, with the same dry, dusty pedagogical ideas from decades ago trying to disguise their creakiness by clothing them in a new suit of educational psychobabble. Since I'm not just writing about the process but I'm actually living it every day as my own guinea pig, I'm working out what does and doesn't work. It will result in a higher quality product, but takes a lot more time, too.

It's exciting times behind the scenes here, but it still doesn't explain where Keyboard & Rudder has been for the last several weeks. The short answer is: "Oops."

The long answer is that I had a queue of several posts lined up and scheduled to automatically post every Wednesday morning for you. That way things would roll along seamlessly while I worked on the dozen different things I'm up to right now. Unfortunately, although I clicked "Schedule" on them, I didn't also click "Publish" on them afterward, so when their assigned time came they sat patiently waiting for the permission to go out to the world, which I didn't realize I hadn't given them.

In other words, it's been NORDO (the aviation term for a plane whose radios have failed--"NO RaDiO") because I was a Dumbo.

I apologize, and see you next Wednesday!

Like Larry the Flying Guy on Facebook:

Follow @Lairspeed

The author is an airline pilot, flight instructor, and adjunct college professor teaching aviation ground schools. He holds an ATP certificate with a DHC-8 type rating, as well as CFI, CFII, MEI, AGI, and IGI certificates, and is a FAASafety Team representative and Master-level participant in the FAA's WINGS program. He is on Facebook as Larry the Flying Guy, has a Larry the Flying Guy YouTube channel, and is on Twitter as @Lairspeed.

It takes hours of work to bring each Keyboard & Rudder post to you. If you've found it useful, please consider making an easy one-time or recurring donation via PayPal in any amount you choose.

Goldilocks and the Three Descent Rates: Too much, too little, and just right

Recently, I created a video where I mash up Grand Theft Auto: San Andreas and Microsoft Flight Simulator X into a lesson on how to figure out where you're going to land, and whether you're going to be too high, too low, or just right. A viewer over at the Larry the Flying Guy YouTube channel asked what is too much of a descent rate in a small plane. Let's answer this, but first, the video:

I make it a point to reply to comments on the channel (just as I do here), and in the course of replying, it became obvious that this was going to be too long a subject to fit into one comment.

First, let's figure out what a proper descent rate is. Sounds simple enough, right? Well, it is and it isn't. It's incredibly easy if you're doing an instrument approach or a long straight-in. Ironically, it's more complicated if you're out flying on a clear blue day just puttering around in the pattern.

Let's get the easy one out of the way first. If you're on an instrument approach or tower tells you to make a five-mile straight in for the runway, 99% of the time you're going to be coming in on a 3° glidepath. It doesn't matter if I'm flying the 172 into old Lorain County Regional Airport or the Dash-8 into Newark or Washington-Dulles International Airport, I'm still going to be coming in at the same angle.

(That's nice, but what does a "3° glidepath" mean? In its simplest terms, it means you go down 300 feet for every 1 nautical mile you go forward. If you're on a 3° glidepath for 3 miles, you'll lose 900 feet of altitude. 5 miles? 1500 feet. 10 miles? 3000 feet. And so on.)

Since you're going to be doing the same thing every time, it sure would be nice if there was a rule of thumb you could use to get the descent rate you'll need quickly. There isn't one. There are two! Both of them are simple, so use whichever one you find easier.

You'll need to know your groundspeed for either one of these. If you've got a GPS, all it knows is groundspeed, so whatever it says it is what it is. If you don't, then you'll need to know your wind components and subtract the headwind from your airspeed to get a precise answer. This can get messy (although there are some rules of thumb to help you out), and the winds you're probably to be doing your private or instrument training in aren't likely to be strong enough to make more than a 10-20% difference in the final answer anyway. This is why we're just going to assume your groundspeed is the same as your airspeed from here on out.

Method one: Take half your ground speed and add a 0.

If I'm flying the 172 at 80 knots: 80/2 = 40. Add a 0 for 400 feet-per-minute (FPM).

If I'm flying the Dash-8 at 110 knots: 110/2 = 55. Add a 0 for 550 FPM.

If I'm flying the Space Shuttle at 300 knots: 300/2 = 150. Add a 0 for 1500 FPM.

Method two: Multiply your groundspeed by 5.

If I'm flying the 172 at 80 knots: 80 x 5 = 400.

If I'm flying the Dash-8 at 110 knots: 110 x 5 = 550.

If I'm flying the Space Shuttle at 300 knots: 300 x 5 = 1500.

This rule of thumb is actually how I calculated the descent rate during the planning for the River Visual 19 into Washington-National  videos. Using this in reverse is why I picked 90 knots to fly it at, since 90 x 5 = 450, which is a manageable rate that also gets me there in a reasonable amount of time. The 300 feet per nautical mile rule is why the chart designers picked what they did when they created the approach:

Now that's all well and good, but when you're flying the pattern, you're not going to be coming in on a 3° glidepath. You're going to be coming in at closer to a 5° glidepath when you're working the pattern. This is a nice balance between being close enough to the runway to still make it if the engine quits and not being too steep.

Does this mean you have to throw Method 1 and Method 2 out the window? Not really. Since 4.5 is 50% more than 3, you can adjust them to fit. (Unlike the first example, they don't give the same result, but they're close enough. They will equal each other if you change the second method to 7.5, but if you can multiply things by 7.5 in your head, you're a better mental math wizard than the rest of us.) There's also a third method in this case, which is the one I use.

Method one: Take half your ground speed and add a 0. Take half of the result and add it to itself.

If I'm flying the 172 at 80 knots: 80/2 = 40. Add a 0 for 400 feet-per-minute (FPM). Half of 400 is 200. 400 + 200 = 600 FPM.

If I'm flying the Dash-8 at 110 knots: 110/2 = 55. Add a 0 for 550 FPM. Half of 550 is 275. 550 + 275 = 825 FPM.

If I'm flying the Space Shuttle at 300 knots: 300/2 = 150. Add a 0 for 1500 FPM. Half of 1500 is 750. 1500 + 750 = 2250 FPM.

Method two: Multiply your groundspeed by 8.

If I'm flying the 172 at 80 knots: 80 x 8 = 640.

If I'm flying the Dash-8 at 110 knots: 110 x 8 = 880.

If I'm flying the Space Shuttle at 300 knots: 300 x 8 = 2400.

Method three: Forget about your vertical speed indicator and use your eyeballs.

In the pattern, all this math is too complicated because you're changing airspeeds and flap settings at the same time. If you learned (or are learning) in a 172, you probably hear "85, 75, 65" in your head to this day, meaning drop a notch of flaps and pitch for 85 knots. Drop another notch and go to 75. Drop the third and go to 65. Do you want to do arithmetic or do you want to fly? You probably can't do both at the same time, especially since your descent angle is also changing every time you add flaps—after all, that's one of the reasons airplanes have flaps.

If you covered my vertical speed indicator (VSI) and asked me what my descent rate is, two things would happen. First, I would have no idea you covered it up, because I don't look at it in the pattern. I'm looking at the runway numbers at that point in the flight, not the instruments. Second, I'd answer you not with a number but with one of three answers: "Not enough", "Too much", or "Just right".

Don't believe me? I take this to the ultimate test in my very first YouTube video ever, where I fly around the entire pattern with the glass panel completely off, so there are no instruments to look at whatsoever!

How do I know if I have the correct descent rate without the VSI? As I look at my aiming point, one of three things is happening:

1. It's moving down my windscreen = "Not enough."

2. It's moving up my windscreen = "Too much."

3. It's staying at the same point in my windscreen = "Just right."

Each of these has a fix:

1. "Not enough" = reduce power some.

2. "Too much" = add some power.

3. "Just right" = don't touch anything.

Again, if you're in a 172, you're in luck because you have a nice rule of thumb for how much to change the power to start a descent. For every 100 FPM more of descent you want, reduce power by 100 RPM. If you want to reduce your descent rate, add 100 RPM for every 100 FPM you want to reduce it by. But what if you don't have a VSI or you had me as an instructor so you had to fly with no instruments at all before you were allowed to solo?

Simple:

1. "Not enough" = reduce power some. If your aiming point is still moving down after you've given the plane a few seconds to respond, reduce a little more. If it's going up now, you reduced too much. Add about half of what you just reduced it by. (In other words, if reducing the power by 100 RPM made the aiming point start moving up, add about 50 RPM back.)

2. "Too much" = add some power. If your aiming point is still moving up after you've given the plane a few seconds to respond, add a little more. If it's going down now, you added too much. Take out about half of what you added.

3. "Just right" = don't touch anything.

By "some" I mean "a little". Don't make massive power changes or your descent will look like a camel's back. If you're in a 172, "a little" means about 100 RPM. Don't add or subtract much more than that unless you're obviously way too high or way to low—and in that case, you'll probably want to consider going around instead of trying to salvage an approach that is likely to end up unstable.

I use this same process even when I'm flying the Dash-8. On a normal approach, around 20% power tends to work well. If I'm a little low, I'll add about 5%. If I'm too high, I'll reduce it by about 5%. Just that much of an adjustment almost always fixes things, but if it doesn't, I'll add or subtract another 3% or so. Smaller corrections sooner are better than big corrections later.

I've answered the question of why descent rates matter, but I still haven't answered the commenter's main question. How much of a descent rate is too much in a small plane?

There isn't a hard-and-fast rule. The big answer is that if you have to dive to catch the proper glidepath, just go around and try it again rather than force an unstable approach. Good landings come from good approaches, and greaser landings start a mile before touchdown. The biggest problem most students have is being too high on final, which means more power needed to be reduced abeam the numbers. Fix it then and you won't have to fix it later.

A more specific answer is that anything more than 1000 FPM once you've put the first notch of flaps in is getting close, and it's definitely too much when you've turned final. Once you've put the first notch in and slowed to 85, 1000 FPM is approximately a 7° glidepath. That's steeper than necessary, but at this point in the pattern, you're probably not much below 1000 feet in altitude, so if you bump up against 1000 FPM for a few seconds, you've still got time.

However, once you're on final and slowed to 65 knots, 1000 FPM is closer to a 10° glidepath! If you rolled out on final at about 400 feet and 1/2 mile out, which is right about where you should be, a descent rate of 1000 FPM will kill you in 20 seconds. Our airline's procedures prohibit descents greater than 1200 FPM when we're below 1000 feet. For the same margin of safety in a 172, this would mean no more than about 700 FPM on final. If you have no wind, that's pretty close to what you'll be doing. The more headwind you have, the less FPM you'll need, since your groundspeed will be slower.

Learning to judge whether your spot is moving up or down or not at all is a skill that is perfect to practice in a flight simulator. You can create a scenario where you're lined up on final and practice it several times in less than 10 minutes. In a flight simulator, you don't have to worry about getting dangerously low and you don't have to pay a lot of extra money if you're too high and have to go around, since you can just reset and try again.

Once you get good at judging your height on a straight-in, you can progress to creating a flight at your home airport where you're on midfield downwind and getting ready to start the full descent profile. This is much harder in a flight simulator than it is in real life, since it's harder to look out the side windows in a sim. If you can master this, your training (or your approaches in general) will go much more smoothly, and your investment in time will be repaid by much less money on lessons!

This technique is something I wish someone had told me when I was learning to fly. It wasn't until I read Wolfgang Langewiesche's classic Stick and Rudder (the book that gave Keyboard & Rudder its name) and became a flight instructor that I found out there was an easy way to figure out whether I was on the correct glidepath.

Happy practicing, and see you next Wednesday!

Like Larry the Flying Guy on Facebook:

Follow @Lairspeed

The author is an airline pilot, flight instructor, and adjunct college professor teaching aviation ground schools. He holds an ATP certificate with a DHC-8 type rating, as well as CFI, CFII, MEI, AGI, and IGI certificates, and is a FAASafety Team representative and Master-level participant in the FAA's WINGS program. He is on Facebook as Larry the Flying Guy, has a Larry the Flying Guy YouTube channel, and is on Twitter as @Lairspeed.

It takes hours of work to bring each Keyboard & Rudder post to you. If you've found it useful, please consider making an easy one-time or recurring donation via PayPal in any amount you choose.

The gorilla in the cockpit

Selective attention/blindness isn't just something husbands and teenagers have. Check out this video that demonstrates in only one minute why fixation in the cockpit is a bad thing:

Multitasking was/is a popular buzzword beginning in the 1990s as people began to convince themselves that they really could do more than one thing at a time. As the video shows, this isn't really the case: you can really only do one thing well at one time. You can either count the passes or notice the guest, but you can't do both at once.

Many—in fact, probably most people—will disagree with this statement, which is why they're usually shocked by the reveal at the end of the video. Most people think they're good multitaskers because they're so bad at it that they don't know they're bad at it. This inability to recognize that one is bad at something has been known to science since the late 1990s, and even has its own name: the Dunning-Kruger Effect.

Yes, I know that there are a lot of people who think they can text, watch TV, surf the web on their tablet, and do homework all at the same time. After all, they do it all the time, so it must be possible.

I'm not saying it's not possible, I'm saying that it's not possible to do all of them well. Afterward, if you did all of the above, you wouldn't have had a decent text conversation, couldn't remember anything substantive about the TV program, couldn't pass a 3 question quiz on what you read on the internet, and turned in a substandard homework assignment—all while thinking you had no problem!

One of the reasons people don't realize how bad they are at multitasking is because there is no real-time feedback on any of the things they're doing. If they drop out of the show they're watching to type a text message, they don't notice it. There is no pack of gauges to show how badly one thing is suffering at the expense of another thing.

However, you can't fool physics, and the cockpit is a continuous, real-time demonstrator of an actual multitasking environment. That is precisely why so many beginning students are totally overwhelmed the first several hours. And that's with the instructor handling the navigation, radios, and collision avoidance tasks!

Have you ever held altitude perfectly only to discover you were way off heading? Of course you have. Everyone has. An old joke goes something like this:

Flight instructor: "OK, let's do some straight and level."

Student pilot: "Which one do you want first?"

A main cause of this early difficulty is selective attention. We can only give the majority of our attention to one thing at a time, with a smaller chunk left over for everything else. If we get fixated on one thing (and we are wired to fixate), the other horses stray out of the barn. While we fix those horses, the other ones we had under control wander away. It's why your instructor probably warned (or will warn) you more than once not to let your eyes get fixated on any one instrument.

It would be nice to be able to keep the horses in the barn and in the field in check at the same time, but that's not how our brain is built. Asking it to devote a lot of processing power to more than one thing at a time is like asking your legs to swim and do hurdles at the same time: it's just not going to happen.

If we're bad at multitasking, and the cockpit is a highly multitasking environment, how does anyone learn to fly? The answer is, like all skills, practice.

Practice is what takes the 100 things that are going on at the same time and makes them automatic. As they become more automatic, they require less conscious effort, which frees up your brainpower for other things. As you get better at holding an altitude, your brain doesn't have to work as hard. This means you have more mental reserve left over to hold your heading. As you become better at holding a heading, that frees up processing power to add another task, and so on.

Your first few lessons, you probably won't know where you are, how you got there, or how long you've been there. King Kong himself could be in the back seat with a boatload of bananas and you probably wouldn't notice, since all your brainpower is devoted to trying not to fall too far behind the airplane. Don't worry: this is a perfectly normal part of the learning process. Everyone who has a pilot certificate today went through that same feeling you're going through.

The good news is that as you get better, that overwhelming feeling goes away. The bad news is that it comes back when you start working in the pattern toward solo. The good news? It goes away again as you get better at that.

There is a feeling that never goes away: the feeling of your first solo. So keep it up and don't let any gorilla get in your way!


The author is an airline pilot, flight instructor, and adjunct college professor teaching aviation ground schools. He holds an ATP certificate with a DHC-8 type rating, as well as CFI, CFII, MEI, AGI, and IGI certificates, and is a FAASafety Team representative and Master-level participant in the FAA's WINGS program. He is on Facebook as Larry the Flying Guy, has a Larry the Flying Guy YouTube channel, and is on Twitter as @Lairspeed.

It takes hours of work to bring each Keyboard & Rudder post to you. If you've found it useful, please consider making an easy one-time or recurring donation via PayPal in any amount you choose.

The Permanence of Temporary Things: A Meditation

In the Blue Ridge Mountains of Virginia,
On the trail of the lonesome pine—
In the pale moonshine our hearts entwine,
Where she carved her name and I carved mine;
Oh, June, like the mountains I'm blue—
Like the pine I am lonesome for you,
In the Blue Ridge Mountains of Virginia,
On the trail of the lonesome pine.

—from "The Trail of the Lonesome Pine"

A few hundred million years ago, a river dried up. It had been around for several million years, a barely-noticeable flicker in the geological sense of time. Perhaps it had found a new path, as shallow things sometimes do when things start to change around them. Perhaps its source had dried up and it no longer had anything to draw from, and as its lifespring dried up, it did too.

Whatever the case, its end is lost in the eternal current of time. We would have nothing left to speculate about had it not crossed paths with the Blue Ridge Mountains. Its temporary existence left a permanent pass in this ridge, and a way for things to get from one side of it to the other. It is gone, but it will never leave the ridge it once knew.

Looking eastward from V128, flying from CRW to IAD. If you want to look closer, the coordinates are approximately 38° 29' N, 78° 42' W.

Some millions of years before, that mountain ridge started skyward. Mountains climb when we're not looking. They grow like children, who stay the same day by day but somehow get bigger and bigger by the year. We grow like mountains, shaped by the forces that surround us, made distinct by what we cross paths along with along the way.

Sometime this growing process is tumultuous and chaotic. It is always disruptive, going from what is to what will be. That's why it's called growth. It also happens when we're not looking, or happens too slowly for us to see. We humans are almost as good at not seeing things that are there as we are at seeing things that aren't.

Sometimes the forces we encounter during that growth leave us a bit twisted. Where we are twisted, where the stresses and strains occur, we also end up the tallest.

Some of those we cross paths with cause scars. Those scars, like everything, may seem permanent, but they are no less subject to the erosion of time as anything else. They may seem more solid, more fixed, but their permanence is only temporary.

Handled well—and we all have to handle them—they become a better part of our character. The moon has craters, scars from impacts it suffered long ago with bodies long gone; they are what make it a beautiful fixture in the night sky instead of a plain bright ball. The Grand Canyon draws people from around the planet to drink in its immense, rugged beauty, yet is a scar left by the Colorado River. One of its most endearing features is that as the river carved its way through the plateau, it revealed the layers that are present underneath our feet, yet would never be seen any other way.

Almost yesterday, in geologic time, ice covered much of North America. The ice's day was as temporary as it was recent, but as it made its abrupt retreat, it gouged out permanent scars in the landscape of New York State. These long scars became a beautifully parallel set of lakes: the Finger Lakes.

Those scars are evidence that something's presence—and now its absence—was at one time important. It is the essence of the temporary given permanence.

Not everyone, however, is that important to us. Some pass through our lives like power lines cross mountains: unflinchingly straight while not even scratching our surface.

Others, like this sunset, are even more transient and temporary

yet leave us with a permanent memory of the spiral of light they caused to dance on the ceiling for a few brief moments before they passed on.

Some leave dry passes within us as a trace that they were once there. Others stay with us, filling up and flowing through those passes, and we shape them as they shape us.

And for those whose lives we pass through temporarily, perhaps the best hope we can have is to bring them a rainbow on their cloudy day; a bit of glory in their gloom.

We contain mountains within us, and from the top of those mountains flow rivers that shape others. Unlike mountains made of stone, however, we are made of stronger stuff. We can choose our response to the forces around us and change what kind of water springs from our tops. Only by doing so can our temporariness have a permanent impact.


The author is an airline pilot, flight instructor, and adjunct college professor teaching aviation ground schools. He holds an ATP certificate with a DHC-8 type rating, as well as CFI, CFII, MEI, AGI, and IGI certificates, and is a FAASafety Team representative and Master-level participant in the FAA's WINGS program. He is on Facebook as Larry the Flying Guy, has a Larry the Flying Guy YouTube channel, and is on Twitter as @Lairspeed.

It takes hours of work to bring each Keyboard & Rudder post to you. If you've found it useful, please consider making an easy one-time or recurring donation via PayPal in any amount you choose.