Engine out approaches

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kevin7500

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kevin
Rather than hijack the "3 degree" thread I thought I would start a new one. It seems that there is great concern about loosing the engine on final. I have spent a fair amount of time reading NTSB reports while researching which aircraft I want to pursue purchasing. Engine failure on final is an EXTREMELY rare cause for an accident. You, as a GA pilot, are much more likely to crash due to fuel exhaustion than anything else.

So, how many of you have experienced a complete loss of power on final? Please exclude loss of power due to fuel exhaustion for obvious reasons. I am trying to determine if my attitude is too casual regarding this scenario.

Thanks!
 
kevin7500 said:
So, how many of you have experienced a complete loss of power on final? Please exclude loss of power due to fuel exhaustion for obvious reasons. I am trying to determine if my attitude is too casual regarding this scenario.
Click to expand...

Discounting fuel exhaustion, never in 3300 hours of flying Cessna 150s, 172s, a Tri-Pacer and a Cherokee.
 
I've had a partial loss of power (enough that I couldn't hold altitude) a few miles from the airport. (throttle failure). A glide to the airport along with a tight pattern directly over it made it a non-issue.

Never had a power loss on final or in the pattern.
 
I think one reason the probablility of power loss on arrival is higher than in cruise is that you're making a fairly significant power change and are more susceptible to induction icing.

Obviously some airplanes and some engines are more susceptible than others. Many of the Aeronca guys flying behind A-65s routinely add carb heat every so often in cruise flight because those engines have a reputation for making ice.

My Lycoming O-145 is known for rarely icing up.

Nevertheless, when below 1500 RPM I add carb heat.
 
Lost power in cruise once due to carb ice, quickly solved. Still, I run my patterns fairly close and high, and slip in in on final. It may be rare, but it only has to happen once for you to die.
 
steingar said:
No, in my old Cessna 150. Cessnas seem more prone to carb ice for some reason. Ted would probably know why. I was already on final for a strip when the power came back on.
Click to expand...
Ah ok.

I think the reason that the Pipers are less prone to ice is that the engine exhaust is routed in such a way that the carbs get to be a little bit warmer than they do in Cessna installs.
 
kevin7500 said:
Rather than hijack the "3 degree" thread I thought I would start a new one. It seems that there is great concern about loosing the engine on final. I have spent a fair amount of time reading NTSB reports while researching which aircraft I want to pursue purchasing. Engine failure on final is an EXTREMELY rare cause for an accident. You, as a GA pilot, are much more likely to crash due to fuel exhaustion than anything else.

So, how many of you have experienced a complete loss of power on final? Please exclude loss of power due to fuel exhaustion for obvious reasons. I am trying to determine if my attitude is too casual regarding this scenario.

Thanks!
Click to expand...

Ok, to be clear since I was one who commented on power off approches.

The concern is not a loss of power in the pattern - the chances of that are very low. But, if you can't hit a 3000 foot runway from a power off on downwind first time every time, the chances of sucessfull off airport landing in a small pasture are probably even lower.

If you do regular power off approches, I firmly believe that you are more likely to succeed at a real power off.

If the last time you did a power off approch was your last flight review (and perhaps not even then) - good luck.

Edit: Misread numbers. See post below.
The 2008 Nall report (http://www.aopa.org/asf/publications/08nall.pdf)says 78% of the fatal accidents were caused by powerplant or fuel system failures, or loss of power for unknown reason. Seems to me to be an area where some improvement is needed...
 
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Capt. Geoffrey Thorpe said:
The 2008 Nall report (http://www.aopa.org/asf/publications/08nall.pdf) says 78% of the fatal accidents were caused by powerplant or fuel system failures, or loss of power for unknown reason. Seems to me to be an area where some improvement is needed...
Click to expand...

I think that's 78% of mechanical-related fatal accidents, not 78% of all fatal accidents. Mechanical-related accidents are something like 7% of the total. Last time I checked, stupid pilot tricks were still the biggest overall killer at 75+%.


Trapper John
 
In 700 hours of flying (which is roughly 1000-1100 hours of engine operation) I've never had an engine fail on me.

To the carb ice issue: I don't know for sure, but my understanding is that it's a design issue. Continentals have an induction system with a carb, plenum, and intake pipes. On Lycomings, the plenum and some of the pipes are in the oil sump, and the carb is bolted to the oil sump. The heat from the oil keeps the carb warm, aids fuel atomization, and reduces tendency for carb ice.

At least, that's what I've been told. Don't know if it's what really happens or not, but it makes some sense to me. It could also just be the carb design in general.
 
Ted DuPuis said:
In 700 hours of flying (which is roughly 1000-1100 hours of engine operation) I've never had an engine fail on me.

To the carb ice issue: I don't know for sure, but my understanding is that it's a design issue. Continentals have an induction system with a carb, plenum, and intake pipes. On Lycomings, the plenum and some of the pipes are in the oil sump, and the carb is bolted to the oil sump. The heat from the oil keeps the carb warm, aids fuel atomization, and reduces tendency for carb ice.

At least, that's what I've been told. Don't know if it's what really happens or not, but it makes some sense to me. It could also just be the carb design in general.
Click to expand...

The heated induction air reduces power output (which is why the 65-LA is more like 55 hp)
 
Capt. Geoffrey Thorpe said:
Ok, to be clear since I was one who commented on power off approches.

The concern is not a loss of power in the pattern - the chances of that are very low. But, if you can't hit a 3000 foot runway from a power off on downwind first time every time, the chances of sucessfull off airport landing in a small pasture are probably even lower.

If you do regular power off approches, I firmly believe that you are more likely to succeed at a real power off.

If the last time you did a power off approch was your last flight review (and perhaps not even then) - good luck.

The 2008 Nall report (http://www.aopa.org/asf/publications/08nall.pdf) says 78% of the fatal accidents were caused by powerplant or fuel system failures, or loss of power for unknown reason. Seems to me to be an area where some improvement is needed...
Click to expand...

Exactly my feeling and having seen two airplanes crashed just off the end of the runway here locally in the past year (or so) and at least that many more in the past few years, I certianly get the idea that pilots are not practicing power off landings enough. Or having power failures near the airport at a point where they can't make the runway.

It is pretty easy to find the NTSB reports where power is lost in the pattern or near an airport were the pilot should have been able to land on the runway and didn't. Anyone see the Piper in the tree photo?

I do teach power on approaches as there is a time and place for them, but I feel a good percentage of landings should be normal power off approaches where you practice how to vary the ground track and airplane configuration to land at the place and speed you desire.

I have had the engine quit at least twice in the pattern, because the runway was within easy gliding range, both were non events.

Brian
 
Trapper John said:
I think that's 78% of mechanical-related fatal accidents, not 78% of all fatal accidents. Mechanical-related accidents are something like 7% of the total. Last time I checked, stupid pilot tricks were still the biggest overall killer at 75+%.


Trapper John
Click to expand...

I sit corrected.

How about this:

About 10% of the time when there is a powerplant / fuel / loss of power accident it is fatal.

What I don't know is how many power loss events don't result in an accident (fatal or otherwise).

But I still firmly believe that there is lots of room for improvement. And I strongly suspect (based on what I read and observe at the airport) that many of these accidents / fatalities were a result of not making it into whatever landing point was selected.
 
dmccormack said:
The heated induction air reduces power output (which is why the 65-LA is more like 55 hp)
Click to expand...

Unless they used a different method of rating engines when yours was made (which is possible), that doesn't make sense. You could argue that the heated induction makes for lower power (it probably does), but the engine is then rated with that power, whatever it is.
 
Ted DuPuis said:
To the carb ice issue: I don't know for sure, but my understanding is that it's a design issue. Continentals have an induction system with a carb, plenum, and intake pipes. On Lycomings, the plenum and some of the pipes are in the oil sump, and the carb is bolted to the oil sump. The heat from the oil keeps the carb warm, aids fuel atomization, and reduces tendency for carb ice.
Click to expand...

This is what I've been told as well.
 
kevin7500 said:
It seems that there is great concern about loosing the engine on final.
Click to expand...
Just a couple of comments about this statement.

I agree that is very rare but there are several things we do in training that makes it look like we're more worried than warranted.

First is the come in high enough to glide to the runway and second a lot of power off landings from abeam the numbers.

In my view we train for both of these because they are applicable to any power failure. I train for off airport landings to maneuver as necessary to be abeam your intended touch down point at 800-1000' AGL then do like we practice in the pattern.

I'll add that coming in on final high enough to glide to the runway is free insurance against that one in a million failure.

Joe
 
kevin7500 said:
So, how many of you have experienced a complete loss of power on final? Please exclude loss of power due to fuel exhaustion for obvious reasons. I am trying to determine if my attitude is too casual regarding this scenario.

Thanks!
Click to expand...

iirc, a few people from rec.aviation.* have had carb ice problems
(even in a cherokee). Google Roy Smith, rec.aviation.piloting, Archer.
 
Capt. Geoffrey Thorpe said:
What I don't know is how many power loss events don't result in an accident (fatal or otherwise).
Click to expand...
I don't think anybody knows that number. And without knowing how many engine failure events end successfully, we don't know how big or how small the problem is.

But I still firmly believe that there is lots of room for improvement. And I strongly suspect (based on what I read and observe at the airport) that many of these accidents / fatalities were a result of not making it into whatever landing point was selected.
Click to expand...
I wouldn't disagree with that. Here's one where the pilot and jumpers tried to make it to the airport, skipping over several good off-airport landing spots. End result, 6 dead.

http://www.ntsb.gov/ntsb/brief2.asp?ev_id=20001211X09633&ntsbno=CHI98FA106&akey=1


Trapper John
 
Carb ice has caused quite a few engine failures in the pattern and final.

I, fortunately, have not had any significant loss of power situations.

That said, runway length permitting, I always try to fly any approach on the high side, to ensure making the runway if a failure occurs.



kevin7500 said:
Rather than hijack the "3 degree" thread I thought I would start a new one. It seems that there is great concern about loosing the engine on final. I have spent a fair amount of time reading NTSB reports while researching which aircraft I want to pursue purchasing. Engine failure on final is an EXTREMELY rare cause for an accident. You, as a GA pilot, are much more likely to crash due to fuel exhaustion than anything else.

So, how many of you have experienced a complete loss of power on final? Please exclude loss of power due to fuel exhaustion for obvious reasons. I am trying to determine if my attitude is too casual regarding this scenario.

Thanks!
Click to expand...
 
I see the point regarding simulated engine failures....thanks.

I am sure that everyone is announcing that on the CTAF as well. :lol:
 
Ted DuPuis said:
Unless they used a different method of rating engines when yours was made (which is possible), that doesn't make sense. You could argue that the heated induction makes for lower power (it probably does), but the engine is then rated with that power, whatever it is.
Click to expand...


You would think so...

But then all the Lycoming engine docs end before the carb installation.

So my guess (only!) is that the HP rating was based on a bench test with the spec prop.

Wrap in a cowling and bolt on a different carb, and the heat goes up, the HP goes down.
 
dmccormack said:
You would think so...

But then all the Lycoming engine docs end before the carb installation.

So my guess (only!) is that the HP rating was based on a bench test with the spec prop.

Wrap in a cowling and bolt on a different carb, and the heat goes up, the HP goes down.
Click to expand...

Horsepower ratings are based on dyno runs, not flight stand. The horsepower as installed in the airframe may be different due to air inlet system restrictions and exhaust system restrictions. From the carb to the exhaust port (or turbo outlet) is how the airframer receives the engine, and then bolts on their exhaust systems and air filters.

So, if your plane has a more restrictive exhaust and air filter, then yes the horsepower would be down. However the carb is part of the engine certification, so that and the induction system would not change.

Things may be different on your aircraft, but that's my understanding of how we've done things since the 1950s or 1960s. My engine is certified with a Bendix RSA-5 fuel injector, for example. Putting on something else would change performance characteristics, and require recertification.
 
It doesn't matter to me if the risk of engine failure in the pattern is very low. What does it cost you to perform a power-off approach? Nothing. Engine problems in the pattern can and do happen. As pilots, don't most of us take pride in flying an airplane well? Then why not do them simply for the sake of good flying technique, pure satisfaction, and prudent practice? Power on approaches for most pilots are a crutch, not a necessity. If a Pitts can make a power-off approach, so can your airplane. :D Yes, I know bush pilots need to fly power on approaches...:yesnod:
 
Back in the '80's. Continental 65 on '46 Chief. Temp. ~ 88*, humid hazy. Descending from 2500' power on to pattern alt. Carb. heat on @ mid field. Cut the throttle when the landing spot was 45* off the shoulder, cleared engine ~ every 30 seconds. On short final looked to be a hair low so moved the throttle in and it quit cold. Wheels bounced off of the berm at the end of the runway and plopped down and rolled to a stop. Felt the carb and it was very cold. Waited a few minutes and it started right up and ran fine....Was always taught to keep a close pattern, it works when you need it. h
 
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whifferdill said:
It doesn't matter to me if the risk of engine failure in the pattern is very low. What does it cost you to perform a power-off approach? Nothing. Engine problems in the pattern can and do happen. As pilots, don't most of us take pride in flying an airplane well? Then why not do them simply for the sake of good flying technique, pure satisfaction, and prudent practice? Power on approaches for most pilots are a crutch, not a necessity. If a Pitts can make a power-off approach, so can your airplane. :D Yes, I know bush pilots need to fly power on approaches...:yesnod:
Click to expand...

+1 Whifferdill

I have had 2 engine problems in 17,000 hours, 1 in a 3 engine jet so a non event and 1 in a single engine Ag-Cat where the fuel vent froze and formed a vacuum in the tank keeping the fuel from getting to the engine. A succesful off airport landing was made because I try to make every landing a practice engine out landing. (Not in the jet, of course.)
 
Ted DuPuis said:
Which doesn't necessarily make either of us right. :)
Click to expand...


You are both right. The Lycoming has the carb mounted to the oil sump, either on the bottom or the rear, depending on engine model, and the carb spider is cast into the sump. The whole thing gets pretty warm but it's not ice-proof, just has a much lower incidence of carb ice. The small Continentals found in many old airplanes and in 150s and old 172s all have their carb mounted to a separate spider bolted to the bottom of the crankcase, via two studs that don't transfer nearly the heat to the carb that the Lyc setup does.

Practice forced approaches can turn into the real thing if the carb heat isn't on, or if the engine isn't run up periodically in the glide. A few seconds of power won't do it if the dewpoint is high enough. The carb heat comes from around the muffler or exhaust piping, and those bits get cooled right off in a throttle-closed glide. The engine needs to warm them up hot enough and long enough to get enough heat long enough to remove any accumulated ice. It takes time and 5 or ten seconds probably won't do it.

Some induction systems have low spots where fuel will puddle at idle in a long glide if the carb is a bit of a slobbery one, and some of the MSA carbs are like that. When the throttle is opened this liquid is sucked into the cylinders and the mix gets too rich to burn and the engine quits, maybe long enough to make a real forced landing out of it.

Lycoming cutaway:
lycoming_engine.jpg


Continental O-200:
o200d.jpg


Note the carb at the bottom, and how the Lycoming has in bolted to the oil sump while the Continental has it bolted to the four-way spider (the picture shows "manifold pressure" pointing to the small port on the spider). The carb is a long way from the hot crankcase and will run colder than the Lycoming's, and ice up more often.

Dan
 
Flying behind engines, I've always favored a (visual) final that looks, at least at first, like I could glide in safely without power. Some planes won't allow that, but most will.

In a sustained descent, the throttle is the up-down control, after all... just seems logical to me.

For me, power on final is just something extra to work with if the air tries anything funny (downdrafts, gusts,etc. can spoil even a perfect close-in approach), or if I have had to extend my downwind for traffic (but even then, I never drag it in- I'll come a bit closer at or near TPA and glide from the usual point, more or less).


And coming in from the abeam point at idle is just fun, as well as useful practice (despite the rarity of engine failures and the risks inherent in prolonged idling).

Anyone who would like learn to appreciate it, but can't bring themselves to throttle back a working engine should solo a glider sometime. Cures you of that problem in one approach, guaranteed. :D
 
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steingar said:
Still, I run my patterns fairly close and high, and slip in in on final. It may be rare, but it only has to happen once for you to die.
Click to expand...
There are single-engine airplanes which simply cannot fly a power-off approach from recommended TPA (1000 AGL) no matter how tight they fly the pattern. In addition, there are many that require a pattern so tight that they will cut off anyone else in front of them unless they take so much spacing that someone else will fill the space. So this is a valid concern. However, as noted above, the statistics show that engine failure in the pattern (particularly on final) isn't a significant enough problem that folks should be flying patterns so tight they can lose the engine and still make the planned runway from anywhere in the pattern.
 
Areeda said:
In my view we train for both of these because they are applicable to any power failure.
Click to expand...
And for that reason, while I think it should be practiced, I think the 180-degree power-off approach should be considered an emergency, not normal, procedure, and practiced only when it doesn't interfere with normal pattern operations.
 
Ron Levy said:
There are single-engine airplanes which simply cannot fly a power-off approach from recommended TPA (1000 AGL) no matter how tight they fly the pattern. In addition, there are many that require a pattern so tight that they will cut off anyone else in front of them unless they take so much spacing that someone else will fill the space. So this is a valid concern. However, as noted above, the statistics show that engine failure in the pattern (particularly on final) isn't a significant enough problem that folks should be flying patterns so tight they can lose the engine and still make the planned runway from anywhere in the pattern.
Click to expand...

Yeah, I tried a power off approach twice in the Cherokee 6 during my primary training and I couldn't do it. My gruff and very old school instructor said, "Gimme that yoke. I'll show you how to do it." He came up short too.
I finally managed it during my last BFR. It required a very tight steeeeeeeep, continuous turn (and a lot of pucker). I was still banking as we crossed the threshold.
 
COFlyBoy said:
Yeah, I tried a power off approach twice in the Cherokee 6 during my primary training and I couldn't do it. My gruff and very old school instructor said, "Gimme that yoke. I'll show you how to do it." He came up short too.
I finally managed it during my last BFR. It required a very tight steeeeeeeep, continuous turn (and a lot of pucker). I was still banking as we crossed the threshold.
Click to expand...
You think that's something, imagine trying it in a Glasair III. That bugger loses 2000 feet in a power-off 180-degree turn.
 
I definitely think that the power off approaches are a useful and necessary skill. I felt much better about my skills when I finally managed it. I plan to practice them much more often.

However, I would never get my wife back in the plane if I made a power off approach with her in the airplane. I think I get somewhere between 1250 and 1500 FPM descent at best glide.
 
3 engine outs flying 2 stroke "Ultra Lights". It's not a matter of if, it's a matter of when 2 stokers quit. However, not a problem in Nebraska. The whole state is a runway, except for a few cows and center pivots. :lol:

Those were the days. :eek:
 
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COFlyBoy said:
I definitely think that the power off approaches are a useful and necessary skill. I felt much better about my skills when I finally managed it. I plan to practice them much more often.

However, I would never get my wife back in the plane if I made a power off approach with her in the airplane. I think I get somewhere between 1250 and 1500 FPM descent at best glide.
Click to expand...

I feel better about my approaches after my instructor was pointing out that my descent rate was excessive at 850 fpm when I thought it was fine at that particular point. After all, the rate can change as adjustments are made.
 
Ron Levy said:
There are single-engine airplanes which simply cannot fly a power-off approach from recommended TPA (1000 AGL) no matter how tight they fly the pattern.
Click to expand...

I'm curious which ones and why??

COFlyBoy said:
Yeah, I tried a power off approach twice in the Cherokee 6 during my primary training and I couldn't do it.
Click to expand...

Nonsense...you just didn't plan your pattern and approach correctly. Let's say you fly a tight downwind 1200' from runway centerline at normal TPA. Are you saying that if you pull power abeam the numbers and immediately start a shallow 180 degree turn, that you will be short of the threshold before you complete the turn? That would require close to a 45 degree descent angle. Or lets say you extend your downwind 1200' past the threshold and fly a square base leg while keeping power in so that you turn final, still at pattern altitude, 1200' from the end of the runway. If you now flew a power-off final approach, think you wouldn't make it? You'd probably have to go around.

I could be wrong, but still haven't heard anyone convince me why they absolutely can't fly a power-off approach in their airplane (or why it would be unsafe)...ATC issues or other planes in the pattern notwithstanding.
 
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