When you’re flying a few thousand pounds of single-engine airplane over people’s heads, they reasonably expect that you’d be able to land accurately if the engine should quit. This is doubly true if you’re being paid to carry innocent passengers.
So, it’s distressing that the power-off 180 is a commonly failed task on the Commercial Pilot Airplane flight test. Even those who pass often attribute their landing accuracy to luck.
In the image above, you can see the FAA’s diagram of a Power-Off 180 on the right. It’s not hard to find the similarities with the Emergency Landing Pattern for military aircraft (as shown in JO 7110-65BB, a.k.a. “The Air Traffic Control Bible”) on the left.
Most of the single-engine airplanes in the U.S. military have turbine engines, swept wings, and speedbrakes. Few general-aviation singles have any of those. Instead of borrowing techniques from the high-performance world, perhaps we should be looking at the lower performance world.
The Glider Pilot Approach
Glider pilots are generally good at landing accurately without power. It’s not that glider pilots are exceptionally skilled (although we’ll probably tell you that we are), or that our aircraft have a very low landing speed (although that does help), or even that we get a lot of practice. The difference is that gliders have either continuously adjustable dive brakes or something similar.
Dive brakes are used much like a throttle. If I push my dive brake handle forward a bit, the dive brakes close a bit, and my glide is extended a bit. If I pull it back, I add some brake, and I sink a little faster. What our airplanes need are dive brakes.
Forward Slips
As a maneuver, the forward slip is the training airplane’s version of dive brakes. The amount of brake we have is determined by the amount of rudder we use. More rudder will make us sink at a higher rate, and less rudder will make us sink at a lower rate.
Because all slips are aerodynamically the same, you can slip any airplane that can do a crosswind landing. But that doesn’t mean that there are no limits or guidance.
Extended slips in some airplanes can lead to fuel starvation issues, compressor stalls, or aerodynamic oddities. Be sure you know the guidance and limitations associated with your airplane.
Flying a Power-Off 180
The Initial Point
Your approach to a landing starts at a place glider pilots call “the Initial Point” or the “IP.” Simply put, we get good at flying the approach from the IP. The ACS mandates that our IP is abeam our touchdown point on the downwind.
In the real world, your engine probably won’t fail right at the IP. So, the first part of an emergency approach is to glide to the IP so we can leave it on the downwind leg at pattern altitude. If you leave the IP either high or low, at least you know where you stand.
Turning Base
Deciding when to turn base is more art than science. Your primary consideration should probably be the wind.
If you’re landing into the wind, you probably have a tailwind while you’re on the downwind leg. If that wind is strong, your groundspeed will be high, and your instincts will tell you to fly a wide pattern. That won’t work.
When you turn toward the runway, you’ll be turning into the wind. A 25 knot tailwind suddenly becomes a 25-knot headwind, which reduces your ground speed by 50 knots. You’ll be fighting that headwind for quite some time.
The faster your groundspeed on downwind, the closer in your base turn needs to be.
Turning Final
You don’t need to fly a square traffic pattern. If you feel like you’re getting low on base, cut the corner to final. If you feel like you’re high, fly a full base leg. Either way, plan to turn final just a little bit higher than you need to be.
Final Approach
Once you’re on final, you’re ready to start slipping. Pick your aim point so you’ll have enough room to flare before you get to your touchdown zone. For most airplanes and approach speeds, the aim point should be about one or two centerline stripes before the touchdown zone. You’ll need to experiment to see what works for your airplane and technique.
On final, it’s important that you hold the right approach speed and that you keep the airplane under control. Use your ailerons to keep yourself over the extended centerline and use pitch to maintain your target airspeed. (You’ll be going a bit faster than indicated due to the pitot tube being turned, but that’s OK.)
Ideally, you’ll be deflecting your rudder about halfway. If you start to get high, you can add more rudder. And if you start to get low, you can take some rudder out. Your objective is to keep the aim point the same height in your windscreen the whole way down.
The Flare
Once you get into ground effect, this turns into a normal landing. Transition into a side slip (for any crosswind), level off the airplane in a flare, look to the end of the runway, and float as far as you can. The distance from the aim point to the touchdown zone should be just what you need.
Notes
There are a few little details that we haven’t discussed yet.
Flaps
Flaps are a horrible way to compensate for a bad approach. Decide ahead of time what flap setting you’re going to use and when you’ll put them in. Don’t improvise and don’t retract them in the hopes that you’ll extend the glide. Personally, I try to minimize the use of flaps.
Stretching the Glide
You may find that you’re a little low on final. If you’re not slipping and you’re not going to make the aim point, what do you do? Obviously, this is a good time to try best glide speed, but what if that’s still not enough?
Best glide speed increases with a headwind. Increasing your speed (up to about a half knot per knot of headwind) may help you glide a little farther. More importantly, it will help you avoid unconsciously pulling on the controls, dramatically increasing your sink rate, and risking a loss of control accident.
Practice
Power-off landings are a learned skill and one that atrophies. With some regular practice and the proper use of drag, you can be ready if that engine ever quits. And, you’ll have one less thing to worry about on your Commercial flight test.
When I was working on my ratings my home airport runway is 2300ft long. I never heard of any issues with those who worked on and received their Commercial rating with this maneuver. I’ll bet any jump pilot would not have trouble doing this especially those flying turbines. When I fly skydivers in a turboprop, I almost always land from jump altitude at flight idle power to a runway under 3000ft long. If commercial candidates are now having trouble with this maneuver, kind of makes those who complain about doing pattern work in a C152 prior to flying for the airlines look questionable.
Energy management…better to have extra to scrub than wish you had more. If inbound with engine issues, keep all the altitude you can until over the field, ATC will be on your side if you let them know. Just remember to keep the nose low in an aggressive slip…you’re already significantly yawed, a yawed stall=spin entry.
Go out and practice at altitude, it’s good learning and a fun way to enhance your skills…spend your $$ on slow flt avgas before investing in an AOA device (if you learn what it’s telling you your entire acft becomes an AOA indicator).
Many years ago, many, when I was learning to fly in an Aeronca Champ and finally moving up to the Tri Champ, power off approaches were all we did. And were done as you described. When I would continuously under shoot, my old time instructor, still wearing his mechanics overalls, would just reach forward and turn the mags off. That did get my attention. It was some years , and bigger planes later that I realized I could make power on approaches. That felt so strange …and easy. I still tend to power of at the abeam runway point and just glide the rest of the way, always clearing the throttle once on base. How long I clear it is determined by how much I’m undershooting again.
You beat me to it, Roger.
Back in the early sixties, my uncle taught me that exact procedure (plus slips) to land his flap-less J3 Cub at his airstrip, nestled in the woods along a creek. Bumping the throttle was (and still is, for me) an admission of error.
Unless I’m landing at a controlled airport with traffic screaming up my tail, that’s what I do. It looks right, feels right, and leaves plenty of energy (and mental bandwidth) for things that might pop up. Nowadays I have 40 degrees of flap available, with an infinitely variable handle to control them. I always make the numbers, if not the stripes.
I feel sorry for those flying speedy little craft that were born so under-endowed. 🙂
Where were you learning to fly in the J-3, Aeronca days?
And when I moved up to the “heavy iron” Cessnas and stuff with flaps, after I was taught how to use them, I was then encouraged to not do unless they were needed for their purpose. Just land without, which reduced wear on then as considered by the FBO airplane owner. To this day, I normally just land without. But the newer folks consider that blasphemy and I’m crashing the plane.
I’m more concerned with W&T on all the other components, like tires, wheel bearings, nose-wheel shimmy dampeners and links, et al. I use full flaps for every landing and touch down as slow as possible. Unless there’s a fierce crosswind, of course. Suum cuique.
Kannapolis, NC. The strip is still there (35.421393/-80.621356) but only by virtue of it being declared “unbuildable” due to the periodic flooding of Buffalo Creek (as it always did). There are now McMansions chock-a-block up the hill to the west. I could still land my plane on it, but I’d have to dodge the signs they put up marking the underground natural gas pipeline they ran down most of it. Not a problem for the chopper, except that it is now the private property of the McMansion homeowners association. The only reason that it’s still visible is that they made it a “walking trail” for the McMansion owners.
Wow! My dad was born there and learned to fly there in a Curtis Wright Jr. with a 3 cyl Zekley engine. He began free falling parachute jumping for small airshows at about age 17. I have his newspaper clippings about his daring do back then. He worked part time at the Kannapolis drug store. I have postcards sent there with out his name on them, just a parachute figure. The strip he and his friend flew out of back then was a very short grass strip, probably long gone under a Mc Mansion now. He mentioned an airstrip in Landis frequently. So great. Small World. My Mom was fresh out of University of Missouri School of Journalism and worked for the Kannapolis newspaper. She met my Dad while he was being the Evel Knievel of Kannapolis at the time, riding around on an Indian motorcycle and being the young daredevil of the air. He began to parachute freefalling while handcuffed. Had to get out of the cuffs before he could pull the ripcord. He never divulged to his kids, his grand kids maybe. He would love to have talked to you…but died in ’06. Roger
Thanks for this, Rob. Although I will never have to demonstrate this maneuver on a checkride, it is still very important. One question: You said “Best glide speed increases with a headwind.” I thought best glide speed was independent of any wind?
Consider a situation where you have a 65-knot headwind and a 65-knot (true airspeed to keep the math simple) best glide speed. Your ground speed will be 0-knots… right? But if I speed up to 70-knots, I’ll get a ground speed of 5-knots and will travel further. From that you can extrapolate that glide speed goes up with headwind.
To figure out the exact relationship between headwind and glide speed, you need to dig into the glide polar. Airplane manufacturers don’t tend to publish these, but that doesn’t really matter. If you’re gliding to a runway and you’re not going to make it, try going a little faster. If that works… great! If that doesn’t work, well you weren’t going to make the runway anyway.
One of you is talking about an angle of attack for best L/D (Mike), and one of you is talking about range taking account for the wind (Rob). So imagine this Mike, the wind is blowing at the same speed as the published best glide speed. What is your range over the ground when going into the wind? What is your range if you flew any amount faster than that?
I would add that the jets and our straight winged aircraft behave essentially the same in the flame out pattern. An F-16 has a glide ratio of about 7:1, C-150 closer to 10:1. The real difference in the jet is the speed for that glide ratio… well over 200 knots for the jet. So in the end, the jet needs much more altitude for the pattern because the pattern is MUCH bigger, but it takes nearly the same amount of time from high key to flare.
Best endurance speed is independent of wind as you’re only interested in time aloft. But all glider pilots know that you have to speed up in a head wind to make your destination if you’re on final glide which an engine out landing is by default.
Thank you Rob, Dan, and Doug. I learned a lot today! That’s what it’s all about! Mike
“float as far as you can”? That’s confusing – the maneuver has a specified landing zone of 200′. And how are you going to have good awareness of where that specified landing zone is if you are looking at the end of the runway?
Good summary. Glider pilots like myself learn, or should learn, pretty early that in the landing process, you gotta do what you gotta do. If cows run onto the runway, land. If someone cuts you off, land. There’s no option other than dealing with it. A big mistake is religiously holding onto a neat “book” left-hand pattern. Another option to lose altitude is to S-turn, never 360’s past the key point. Aspire to never lose sight of the runway. A weakness of “key” altitudes is that you may not know the MSL of farmer Smith’s wheat field.
PAPI lights normally set up a visual glideslope of 3 degrees, requiring a 19:1 L/D. (Even all white can be as little as 3.5 degrees.) In a C- or PA-Anything, you ain’t gonna make it with an approach that shallow. (For fun and having a little something extra in the ol’ toobox, I’ve successfully done ILS approaches in my motorglider with the engine OFF).
This sets up a problem since most GA flyers aim for that slope using power to do so. It’s very easy for someone to sneak in under you in a blind spot with bad results. In this regard it’s actually a decent idea to practice, traffic permitting, at a towered airport, where radio use is required and there’s an ATCer keeping the hidden clear.