Engine Out Musings

[DaV8or]

I have always done pretty well at dead stick landings and every two years I get tested by an instructor and have no real issue. I have avoided practicing dead stick landings solo because I'm afraid of an accidental gear up. On the other hand, I also am afraid of the engine quitting as I think it is likely to happen to me one day.

 

So, the other day I was tooling around on a little valley tour and when I got close to my home base, I decided to test my dead stick skills. At about 6500ft, I pulled power to idle, pulled the prop all the way back and trimmed in best glide. It was never a question of whether or not I would make the airport, it was all about what happens after I get to the airport.

 

I show up at the airport and enter the downwind for the runway that the wind favored, but about 3,000 ft above the pattern altitude. So what do you do next? I opted to fly a great big long downwind, but how far? Not being big on math in the cockpit, I used my best guess.

 

I rolled out on final about 1,000 ft too high and so went gear down, flaps down and forward slip. Sorry buddy, this approach ain't workin' out. I gave up on this mess, fired up the engine and initiated a go around.

 

Embarrassing.

 

Had this been a real emergency, I would have made the runway, but I would have skidded off the end of runway, into the dirt and it would have gotten ugly. I probably would have survived, but I doubt the plane would have. Since I'm not going to do some crazy math in the cockpit, more info about sink rates and altitude losing strategies are needed.

 

Round II

 

My next flight out, I went specifically to find out about sink rates. With just me on board and about 50 gallons of fuel, best glide sink was about 600 fpm. This works out to about 350' per mile forward. I then did two standard rate 180 degree turns to the left and two to the right and discovered that a standard rate 180 either way will lose about 800 ft. I then did the same thing, but instead of standard rate, I chose 30 degree bank 180 turns. Guess what? Only lost 400 ft. These are nice round numbers I can work with.

 

I didn't have all day to do this, so back to the airport and I again arrived about 2500 ft too high. On this approach, I flew to the numbers on a crosswind and then did my 180 standard rate turn to the left (it's left traffic) and crossed over the final approach course and then used my newly found 30 degree bank back to the right. This combo had me nicely on final and still high, but this time not crazy high.

 

I chose to go for the gear and flaps followed by a little forward slip. It all worked out pretty perfect with a nice squeaker landing with the engine still at idle.

 

Redemption!

 

On roll out, I realized that I never tried pushing the prop all the way forward and wished I had because I was curious how much that increased the sink rate. I still had some time, so I taxied back, took off and stayed in the pattern and climbed to about 500' above TPA. Pulled to idle and went to best glide. I flew a normal downwind, did the 30 degree bank and ended up a little high on final. Again I chose gear and full flaps, but this time also the prop forward. I slipped a little, however not as much and this time the tires squeaked pretty much on the numbers in a full stall landing.

 

Nice day's work.

 

Anyhow, I still have to do some research and practice strategies for losing altitude, but of course not too much altitude. I like simple round numbers and strategies. Of course the numbers would be different for different weights, but I fly by myself 95% of the time, so these numbers kind of work for me. 

 

I recommend everyone go out and see what numbers you get.

[MARZ]

Dave - great info - the one thing I would do in the "way too high" would be a circle down to a better approach altitude - of course that would be tough to practice unless you knew you were alone in the pattern.  Your experiments at standard and half standard would give a great quick calculation 360 at standard and 360 at half -

 

Now that mine is back from the interior I have a mission for my back in the saddle flight

[Jamie]

Ever since I saw an instructor do that commercial thing where they descend while circling, that's my new favorite way to lose a bunch of altitude in a hurry. I think I'd get almost over the airport, still plenty high and then announce (frequently) that I'm "engine out, circling to descend over [airport] at X,X00." I've never tried it, I know it's not standard phraseology, and there might be other things wrong with the idea. But I very much like the concept of burning altitude over the landing spot, rather than on the way to the landing spot.

 

You mention trying the prop full forward. Any idea how much (fpm) that added to the sink rate?

[DaV8or]

Your experiments at standard and half standard would give a great quick calculation 360 at standard and 360 at half -

 

Exactly! Quick, simple math and you now have a way to loose a known amount of altitude and have an idea of where you'll be at the end of that.

[DaV8or]

You mention trying the prop full forward. Any idea how much (fpm) that added to the sink rate?

 

No. My next experiments may include recording sink rates at landing speed with gear only down, flaps down only and prop forward only. Then depending on how much difference the prop makes, I might try combinations of those three things.

[jetdriven]

Some tools to assist you if you are high on final with engine out.  First, gear down,  flaps full, prop full forward. Still too high? Forward slip. If still too high, then wide S-turns while in a forward slip, then bring speed up to 110 MPH. 

[jlunseth]

I am working on my commercial and this weekend went out and worked on 180 power off landings.  Did a little work last week also.  It turned into an exercise in developing numbers.  My numbers might be helpful.  Bear in mind that I have a 231, and from my experience with a J, the 231 falls more quickly than a J when at idle.  Also, my numbers are a work in progress.

 

I used the proscribed technique, which is to drop the gear on downwind at approach speed and power, pull the power abeam a chosen touchdown point and then pitch immediately for best glide, fly a short downwind, turn to base then final and try to land within 200 feet of your spot.

 

Last week I tried a couple at an airport that had an 800 foot pattern altitude, so I started at 800.  I found that I could not make a 180 and get to the runway from 800 feet.  Even trying required an immediate circle maneuver with no squaring of base or lining up with the runway on final.  It is possible that in a real emergency, had I simply gone for it, I might barely have made the threshhold although I would probably have pranged the plane hitting hard.  I opted to go around instead.  The standard advice is to be at 800 at the point where you turn downwind to base, and I think you need at least that much.  I found in further working on the maneuver, that I need at least 1000' pattern altitude, and I need at least .75 miles from the runway. 

 

I found that using the best glide chart in this situation did help.  My chart shows different best glide speeds depending on gross weight.  The speeds range from 76 at 2300 pounds to 87 at full gross.  It helped to use the speed for the particular weight. 

 

Winds were calm.  I found in my successful attempts from 1000 feet that if I pitched quickly for best glide (actually gaining a little altitude), that I could fly a little bit of a downwind, but that I needed to "cut the corner," viz. take a diagonal to the runway and not square the base to final.  I could then add flaps as needed, with a little bit of forward slipping if necessary, and make my touchdown point. 

 

I used .75 miles from the airport waypoint on the GPS.  Half a mile was just too close.  If I used a max. 30 degree bank, a try from 800' required more than 180 degrees of continuous turn from downwind, in other words I would blow past the runway and would need to continue the turn to get back to it.   With .75 I was able to fly a little bit of a downwind, and make a turn that lined up with the runway.  Now that I know how this works, I am going to try a mile from the runway, which I feel is about the right distance to fly a Mooney pattern with power on.  It allows squaring the base to see possible aircraft on final, and it avoids overbanked turns at slow speed.  I am fairly confident that if I make my base turn as soon as I have achieved best glide, that I can make the touchdown point from the 1 mile distance, I guess we will see.

 

One comment is to resist the temptation to put the nose over to get down to your touchdown point.  You will gain too much speed and hit hard, which is not good for the plane.  I should also say that both of my work sessions have been in calm winds, I have not had a chance to see how the numbers work in crosswinds.

 

I have worked a little on a steep spiral also.  The technique I was taught at one of the Mooney PPP's, is to pick a touchdown point on the runway, pitch for best glide, and circle that point.  The starting point for the first circle should be on the downwind leg (but at a much higher altitude) and abeam the chosen touchdown point.  Note the amount of altitude you have lost on the first circle.  Lets say, hypothetically, that you lost 2000 feet.  You now know that each circle of the runway will give you about 2000 feet, and that you want to start your power off 180 descent to landing from at least 1000 feet, so simple math will tell you how many circles to make.  It is very important to hold best glide speed or your math will be off.  It is unlikely that you will start, let's say, exactly 7000 feet above the runway, which would be three circles and then the thousand feet for the power off 180, so you need to use a little estimation and make whatever maneuver at the bottom of the spiral that you need to get to that 1000 foot spot on downwind.  It is also important, in my view, when doing this circle to a power off 180 landing, to keep the bank mild and below 30 degrees, standard rate is even better.  You are not trying to lose a ton of altitude, you are trying to make a controlled, precise descent.

 

It is possible to use more bank and lose altitude faster.  I guess if you start with an engine out over an airport in the flight levels, you might want to use more bank at the start to lose altitude faster.  I have a couple of comments on that.  First, you have to maintain best glide or something in that vicinity if you are going to use a bank over 30 degrees.  If you allow the plane to speed up it gets very uncomfortable, which means too many G forces.  Second, having had the need to do an emergency descent from the flight levels, I would have to say that you almost never have the luxury of finding yourself directly over an airport, and you are going to have to make up whatever descent is necessary to get you there.  In my case, I had a loss of oil pressure and was very concerned that I make it to the airport with the engine still alive, even if I burned it up making a safe landing, so with engine seizure a possibility at any moment I throttled back and did a straight high speed dive towards the airport 20 miles away, deploying the speed brakes to stay below Vne, and it worked out. 

 

I would have to say that having a set of numbers and a technique that you have practiced in your aircraft would be invaluable in an engine out, but effective problem solving is even more so. 

[DaV8or]

So, I'm back with more numbers. I wanted to see the effect of drag inducing equipment on the sink rate. I figured that since the only time I would actually use the drag would be on final when I'm slowing down to land, I would conduct my experiment at my target landing speed of 75mph. Here are the sink rates at 75mph.

 

Clean-  300fpm

Full Flaps Only-  400fpm

Gear Down Only-  500fpm

Prop Full Forward Only-  400fpm

Full Flaps, Gear Down, Prop Full Aft-  500fpm

Full Flaps, Gear Down Prop full Forward-  700fpm

 

So there it is. I found the prop to be a useful device in controlling sink rate. I'm not sure how it would perform if the engine were truly off and windmilling though. I'm not really willing to test that one I guess.

 

Sadly, I once again tried a simulated engine out from 10 miles outside the traffic pattern and the result wasn't awesome. I pulled the power and set for best glide at what I'm guessing was about 10 miles. I was trying to do this as much as possible without computer aids. I was nothing but pilotage, no GPS help. As expected, I made it to the airport above TPA.

 

I went straight to the numbers for 23 on a heading of about 160. I arrived over the number at 1000 ft above TPA. I chose to do my standard rate turn to the right thinking it should lose me about 800 ft. As I came around, it was looking about right to me and I increased bank angle to get me on final.

 

I had hoped that I would still be too high and need to use drag to get me on the correct glide path, however at best glide, I watched my sink go from above the VASI glide slope to below the glide slope. There was a fair headwind and turbulence (there always is in the summer) and perhaps I didn't calculate for that. I let it go as long as I could, but at some point on short final I gave it a shot of power and landed.

 

Had this been a real emergency I would have perhaps touched down in the dirt in front of the runway. At this particular airport, that would have not been a huge deal, me and the plane would have lived, but at another airport, like Catalina, Palo Alto or Sedona... I'm not so sure.

 

This dead sticking it in from a distance is a tricky business and I need more practice so that I can get proper sight pictures to know what a proper approach should look like. I encourage all of you to go out and give it a go, don't just pull the power in the pattern and think you're good. Go way outside the airport, off alignment with the runway, pull the power and try to put the wheels on the runway without any power. We all imagine this to be no problem, but I find there is a lot to it.

 

Just don't forget the gear!

[DaV8or]

It is possible to use more bank and lose altitude faster.  I guess if you start with an engine out over an airport in the flight levels, you might want to use more bank at the start to lose altitude faster.

 

Thanks for posting your experiences. Your impressions of position and altitude in the pattern are similar to what I'm finding out. As to the bank angle thing, I agree with all that you said, I just want to point out that my findings show that bank angle can be useful in controlling altitude. A 30 degree bank does produce a greater sink rate than a standard rate turn, but the amount of time it takes to get turned around 180 degrees is so much faster, the net result is you can change course and lose a lot less altitude. This is why the "impossible turn" can be possible. If you're climbing out and lose your engine at 500' and try to do a standard rate turn back to the runway, you'll never make it. At 30 degrees bank and holding best glide speed, I'm convinced you would. So in the right time and place, a steeper bank angle can be advantageous and another tool in the tool box.

[Jeff_S]

Dave, that's very interesting data about which drag components will increase your sink rate. But it seems to me that if I were dealing with a true engine emergency, I'd want to use as few variables as possible to keep things simple.  To me, this would mean staying high right up until final, and then using a good hard slip with gear down to bring it home.  The slip is easy to control and get into/out of, without having to fiddle with knobs and things.

 

As it turns out, I get plenty of practice with this approach in regular flying. (Only a few times because of my own misjudgment...often I'm trying to help controllers manage traffic flow at PDK during busy times when they ask if I can take a "short final".)  I'm curious if you experimented with this in your testing. I can get 1500 fpm decent rates with no speed increase if I need them, easy.

[1964-M20E]

Dave great stuff.  i was just wondering what i was going ot do this wekend if the weather cooperates I think I just might go and try some of this on my own.  it's be a while to do this type of stuff.

[N9201A]

Thanks for posting this very useful information.  Everyone should try it and get comfortable with their aircraft's particular characteristics and performance.  There are obviously many variables (two v. three-blade, long-body v. C, pilot technique) but perhaps the biggest one is wind!  

 

Personally I have found slips to be extremely useful descent tool that is really underutilized by most pilots.  Perhaps that is due to stall-spin concerns or the lack of basic stick-and-rudder skills, but watch some landings at your airport and see how many pilots will land long and fast when a little slip would have gotten them down softly and slowly much earlier on the runway.  

 

Practice them at altitude as many have written about above, then arrive with plenty of extra altitude;  besides adjusting bank angles, carrying a little top rudder if a spiraling descent can add an eye-opening amount of drag, which will certainly increase sink rates.  Personally if I've got an engine out and am fortunate enough to arrive very high I am not worried about what kind of pattern I am flying or my ground-based references in relation to what I think my ground track should be:  using fixed points on the ground ("half-mile" etc.) will only work when the wind is EXACTLY the same as when I rehearsed it.

 

While altitude loss may be a constant if your technique is perfect, the wind differences over 6,000 or 7,000 feet may affect ground track, which is what we've got to be planning for because we only have one chance to get it right (I did remember to look or ground cues as to what the wind is doing in all of this, right?).

 

Some say the best strategy is simply set up for least sink rate, which is NOT the same as best glide, but gives you the most TIME aloft.  Slower than best glide, in many aircraft it is reached at idle by simply trimming full nose-up, then leave pitch alone (obviously if you start turning, accept the increased rate of descent for the turn rate, DON'T touch the pitch).  This buys time to troubleshoot, watch the landing site, and potentially declare an emergency if you or your passengers have time.  When you've got the runway made, be high, but dump everything and slip as aggressively as you have to.  

 

The key is the last few hundred feet to the runway (various publications set different "windows" and techniques), but ultimately it comes down to  having complete mastery and comfort level to be able to hit your safe touchdown spot at the right speed every time.  Everyone doing these drills deserves kudos for doing that practice that we all need to develop and maintain this proficiency.  Of course, the good corollary to Murphy's Law is you won't be called upon to exercise the emergency skills on which you're current and proficient.  

[fantom]

 

Some say the best strategy is simply set up for least sink rate, which is NOT the same as best glide, but gives you the most TIME aloft.  Slower than best glide, in many aircraft it is reached at idle by simply trimming full nose-up, then leave pitch alone (obviously if you start turning, accept the increased rate of descent for the turn rate, DON'T touch the pitch).  This buys time to troubleshoot, watch the landing site, and potentially declare an emergency if you or your passengers have time.  When you've got the runway made, be high, but dump everything and slip as aggressively as you have to.  

 

 

I'm one of 'them' that says the above is an excellent technique. Just try it at altitude; it works!

 

Someone mentioned using a 30 degree bank at 500 feet AGL for a possible, 'impossible turn'....deadly advise. If you lose you engine at 500 ft AGL and feel lucky, get you nose way down immediately, go 45 to 60 degree bank, and pray! Best to practice this at altitude also, lest 60 degrees of bank rattles you.

[Parker_Woodruff]

Dave,

If you arrive "way too high," consider the steep spiral which is a commercial pilot maneuver.

Find out how much altitude you lose in a 180 degree turn and a 360 degree turn...540, 720, etc.

[Hank]

You can get an impressive descent rate at moderate airspeed. I think my C was > 1500fpm, below normal cruise IAS.

[DaV8or]

Personally I have found slips to be extremely useful descent tool that is really underutilized by most pilots.  Perhaps that is due to stall-spin concerns or the lack of basic stick-and-rudder skills, but watch some landings at your airport and see how many pilots will land long and fast when a little slip would have gotten them down softly and slowly much earlier on the runway.

 

I have always used forward slips and use them frequently use it in the Mooney. I just found out (see story above) that if you roll out on final and you're way to high, all the slip in the world won't get you to the desired touchdown point. So, the point seems to be to use a strategy to get you on final so that you are high and above the glide slope, but not way to high. I have never tried a forward slip at best glide speed though, only at something close to landing speed.

 

If you are aligned with the runway, like on a long final, It's not so tough. I find it much more challenging if you approach the airport off of runway heading. Like I said, folks should go and try it out. The usual pull the power in the pattern is only so useful. I also think it's really useful to do this by yourself and not with an instructor, or pilot friend. Instructors tend to see you screwing up and then make suggestions, helping you get back on track. Screwing up on your own can be more instructive at times and make you really think about what went wrong.

 

Anyhow, if you're like me and just buzzing around boring holes, it gives you something to do and it's really cheap to be running at about 1.5 gallons a hour! Just don't forget the gear!!

[jetdriven]

I have always used forward slips and use them frequently use it in the Mooney. I just found out (see story above) that if you roll out on final and you're way to high, all the slip in the world won't get you to the desired touchdown point. So, the point seems to be to use a strategy to get you on final so that you are high and above the glide slope, but not way to high. I have never tried a forward slip at best glide speed though, only at something close to landing speed.

 

If you are aligned with the runway, like on a long final, It's not so tough. I find it much more challenging if you approach the airport off of runway heading. Like I said, folks should go and try it out. The usual pull the power in the pattern is only so useful. I also think it's really useful to do this by yourself and not with an instructor, or pilot friend. Instructors tend to see you screwing up and then make suggestions, helping you get back on track. Screwing up on your own can be more instructive at times and make you really think about what went wrong.

 

Anyhow, if you're like me and just buzzing around boring holes, it gives you something to do and it's really cheap to be running at about 1.5 gallons a hour! Just don't forget the gear!!

 

I personally know 4 or 5 people who accidentally gear-up landed an airplane by practicing emergency procedures to a landing. You keep the gear up to reduce drag, and anfter a few minutes you forget it. 

 

One thing I trained myself to never do is to practice an engine failure in flight simulated emergency to a landing. I always go around, and set up for a normal landing.  Now this presents an unusual procedure for the commercial pilot 180 degree power off landing maneuver. The solution for me was power idle-gear down in one move, and start the turn to the runway.

[WardHolbrook]

Good stuff.

Let me put on my CFI-G hat for a minute and recommend a bit of glider training for those of you who might have any questions or doubts of your ability to successfully manage an engine-out scenario in your airplane. It honestly doesn't take very much for a power-pilot to gain the necessary skills and proficiency to get through the checkride in a sailplane. A glider rating will introduce you to a skillset that will transfer directly to just about all of the fixed-wing flying you'll ever do. Your stick and rudder skills will be enhanced and you will gain a confidence in flying without an engine. (Engine? I don't need no stinking engine.) 

[DaV8or]

I personally know 4 or 5 people who accidentally gear-up landed an airplane by practicing emergency procedures to a landing. You keep the gear up to reduce drag, and anfter a few minutes you forget it. 

 

One thing I trained myself to never do is to practice an engine failure in flight simulated emergency to a landing. I always go around, and set up for a normal landing.  Now this presents an unusual procedure for the commercial pilot 180 degree power off landing maneuver. The solution for me was power idle-gear down in one move, and start the turn to the runway.

 

Gear up landing is a real danger with this practice. The gear warning horn fades away in your brain miles away from the airport. I have a secondary gear warning that kicks in under best glide speed but even that could I suppose be ignored if it were on long enough. Your idea of planning to do a go around is a good one and I will probably do that next time. Only down side is you miss out on the real satisfaction of making it all the way and rolling out with the engine at idle the whole time. Still that satisfaction could turn to despair in an instant by forgetting the gear.

[DaV8or]

Good stuff.

Let me put on my CFI-G hat for a minute and recommend a bit of glider training for those of you who might have any questions or doubts of your ability to successfully manage an engine-out scenario in your airplane. It honestly doesn't take very much for a power-pilot to gain the necessary skills and proficiency to get through the checkride in a sailplane. A glider rating will introduce you to a skillset that will transfer directly to just about all of the fixed-wing flying you'll ever do. Your stick and rudder skills will be enhanced and you will gain a confidence in flying without an engine. (Engine? I don't need no stinking engine.) 

 

I'd like to do that. Sadly, they have glider ops on my home field but it's a club, so just to get a little instruction I need to join their club and they want $1600. Otherwise I have to fly to Hollister, or to a private airport up in Willows as best I know. I really don't think I want to go for the rating, I just want to learn to land the thing.

[WardHolbrook]

I'd like to do that. Sadly, they have glider ops on my home field but it's a club, so just to get a little instruction I need to join their club and they want $1600. Otherwise I have to fly to Hollister, or to a private airport up in Willows as best I know. I really don't think I want to go for the rating, I just want to learn to land the thing.

I've never had a private pilot rated student take more than 3 or 4 flights to solo a glider. I'd look around, there are some great soaring schools in some beautiful parts of the country. Getting the glider add-on rating it might make a great combination mini-vacation and BFR substitute.  

[aaronk25]

Even if after a full slip, flaps down, gear put approach if still fast and high better to point it down at runway and level in ground effect than maintain a stabilized approach. Seems to land shorter that way. Anyone else notice this.

I suppose in an emergency flaps could be retracted and it could be forced on to the runway at the expense of totaling the airplane. I suppose better to crash on the run way than go off the end.

I also wish I could get my 77 to feather the prop more the 82' I flew would get down to 900rpms with power off in the glide if the prop knob was firmly pulled all the way out. My 77 will come down to about 1400 and that's it. So mine needs 650-700fpm where the other was 500-550fpm in the glide....