When do you advance props

I was taught to go full forward abeam the numbers after power reduction. My instructor's reasoning was to help slow the aircraft down and the examiner I flew with during my commercial checkride didn't say anything in regard to the technique. After reading some of your thoughts on here I can see why this could be a bad idea, especially considering a tailwind. The flip side to that, on a calm day with a well set up approach I wouldn't see an issue with going full forward, abeam.
 
Back when I flew something with a blue knob (over 2 years ago now) I was taught full forward on base with the GUMP check.
 
If you don't like the pitching moment wait until the props are off of the governor before advancing the props, this is at about 100' to 50' AGL, which is nice, because you get no pitch change, nor do you get any change in sound. Passengers like it, it doesn't reconfigure you down low. If you're worried about overspeeding on a go-around then do what you're supposed to do on a go around anyway, mixture, props, then (and only then) throttle. Deakins wrote a piece about this I think.
 
ppragman said:
If you're worried about overspeeding on a go-around then do what you're supposed to do on a go around anyway, mixture, props, then (and only then) throttle. Deakins wrote a piece about this I think.
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FWIW, I teach throttle always comes first during a go around. The logic is to get the plane climbing rather than descending ASAP, then deal with advancing props and mixtures. It won't damage anything to momentarily run the high power setting with reduced RPM or mixtures.

Of course, that's my logic for quick, unexpected go arounds. If you're talking about a slower, more planned go around (executing a missed approach from an IAP, going around because a plane didn't clear the runway ahead of you, etc.) then your method is probably smoother and better.
 
jrh said:
FWIW, I teach throttle always comes first during a go around. The logic is to get the plane climbing rather than descending ASAP, then deal with advancing props and mixtures. It won't damage anything to momentarily run the high power setting with reduced RPM or mixtures.

Of course, that's my logic for quick, unexpected go arounds. If you're talking about a slower, more planned go around (executing a missed approach from an IAP, going around because a plane didn't clear the runway ahead of you, etc.) then your method is probably smoother and better.
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I don't necessarily agree with that, but let's say your student is on final and the controller gives him a go around before he's had time to complete the before landing checklist, at which point he could be operating at too lean of a mixture setting for the engine to keep running when he goes to max power, that could potentially lead to disaster in the form of a power failure.

In quick and unexpected go arounds you're going to be basically in the flare, where you should have already pushed the prop and mixture forward previously, everything from 100' up, you have time to react. Be it sidestepping and throwing the whips to it, so by 100' agl you should have everything done already (just my opinion on the matter) there are a million ways to do the same thing, of course, so don't take this as bashing or anything.
 
ppragman said:
I don't necessarily agree with that, but let's say your student is on final and the controller gives him a go around before he's had time to complete the before landing checklist, at which point he could be operating at too lean of a mixture setting for the engine to keep running when he goes to max power, that could potentially lead to disaster in the form of a power failure.

In quick and unexpected go arounds you're going to be basically in the flare, where you should have already pushed the prop and mixture forward previously, everything from 100' up, you have time to react. Be it sidestepping and throwing the whips to it, so by 100' agl you should have everything done already (just my opinion on the matter) there are a million ways to do the same thing, of course, so don't take this as bashing or anything.
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No worries, I don't take it as bashing.

In most piston engines (Lycoming 540 series and smaller, such as what you'd find most low time pilots flying) I've never seen a mixture so lean in flight that it will support a reduced power setting (say, 1700 RPM), yet produce a power failure at full throttle.

Take, for example, a typical 172 with an IO-360. Let's say you lean it out for cruise at 10,000 feet. It'll probably be burning about 9 gph, or maybe 8 gph if you have a lower power setting and lean aggressively. Then you don't touch the mixture during your descent for a landing at sea level. You do an unexpected go around, jam full throttle in, and your engine will still get close to 8 or 9 gph. That's probably close to peak EGT, if not slightly lean of peak, but will still work fine and produce plenty of power.

Basically, I know what you're cautioning against in theory, but I can't think of a real world scenario where it would actually happen.

Also, I should reiterate, I agree with you for doing go arounds from higher altitudes. I'm only talking about sudden, quick go arounds close to the ground.

And I'll even share one other scary detail--a lot of times I leave the prop lever pulled back and mixture leaned out all the way to landing. As in, when other pilots say to advance them on short final, I just let 'em be. I'm a real cowboy like that.
 
Stomp16 said:
However, I see no reason for the prop(s) to be red-lined during a landing.
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I don't think a red line should be confused with red lined. The prop will/should always go to the top of the green arc if theres power on the engine. While I agree with you nothing should ever be slammed in-props,power,mixture-I see nothing wrong with putting the props forward whenever a person desires. If there is power on the engine bringing the props forward should be done slowly-say three seconds at least to bring from cruise position to max rpm. While this is purely from a training point of view I would never teach a person to wait until short final or whatever. I always taught abeam the numbers-the before landing should have be completed and then a Gump check base to final.
But hey, thats just me.
 
BajtheJino said:
I don't think a red line should be confused with red lined. The prop will/should always go to the top of the green arc if theres power on the engine. While I agree with you nothing should ever be slammed in-props,power,mixture-I see nothing wrong with putting the props forward whenever a person desires. If there is power on the engine bringing the props forward should be done slowly-say three seconds at least to bring from cruise position to max rpm. While this is purely from a training point of view I would never teach a person to wait until short final or whatever. I always taught abeam the numbers-the before landing should have be completed and then a Gump check base to final.
But hey, thats just me.
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Again, I agree with you. The props should be at the top of the green arc on approach and this should be done when initially setting up for the landing (GUMPS). The red-line is another 2500rpm higher than the top of the green on our gauges. Like I was saying earlier, people will be in the downwind with 20-30kts of tailwind and set-up once abeam. The set up includes full prop. Once they turn from base to final and put that wind off the nose, they "suddenly" don't have enough power in to make the runway. The power goes back in abrublty, the rpms redline. After the engine starts singing and the PIC realizes the prop is not set correctly, 2500rpm gets taken back out. While this isn't a huge deal, forward thinking could have smoothed the approach and abrupt power changes would not have to of been made.
 
Stomp16 said:
Again, I agree with you. The props should be at the top of the green arc on approach and this should be done when initially setting up for the landing (GUMPS). The red-line is another 1500rpm higher than the top of the green on our gauges. Like I was saying earlier, people will be in the downwind with 20-30kts of tailwind and set-up once abeam. The set up includes full prop. Once they turn from base to final and put that wind off the nose, they "suddenly" don't have enough power in to make the runway. The power goes back in abrublty, the rpms redline. After the enigne starts signing and the PIC realizes the prop is not set correctly, 1500rpm gets taken back out. While this isn't a huge deal, forward thinking could have smoothed the approach and abrupt power changes would not have to of been made.
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This post, IMHO, has nothing to do with prop settings, but poor technique all around. If you find yourself out far from the runway like you have stated, you have done something wrong in the downwind, and did not recognize your excessive groundspeed due to the tail wind. Don't you remember rectangular patterns from your PPL days?
 
mshunter said:
This post, IMHO, has nothing to do with prop settings, but poor technique all around. If you find yourself out far from the runway like you have stated, you have done something wrong in the downwind, and did not recognize your excessive groundspeed due to the tail wind. Don't you remember rectangular patterns from your PPL days?
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Not necessarily, sequencing for your "power up final" could be from something as simple as, "Cessna 123AB, I'll call you base."
 
mshunter said:
This post, IMHO, has nothing to do with prop settings, but poor technique all around. If you find yourself out far from the runway like you have stated, you have done something wrong in the downwind, and did not recognize your excessive groundspeed due to the tail wind. Don't you remember rectangular patterns from your PPL days?
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The patterns are fine and the distances are correct. However, the 206's tend to drop like a rock. You can fly a perfect pattern(concerning distance) and not correct for the tailwind. Once that 30kts ends up off the nose and without a correction of power, you'll be well short of the runway. The problem comes when people slam power back in without first backing off the rpms.
 
jrh said:
No worries, I don't take it as bashing.

In most piston engines (Lycoming 540 series and smaller, such as what you'd find most low time pilots flying) I've never seen a mixture so lean in flight that it will support a reduced power setting (say, 1700 RPM), yet produce a power failure at full throttle.

Take, for example, a typical 172 with an IO-360. Let's say you lean it out for cruise at 10,000 feet. It'll probably be burning about 9 gph, or maybe 8 gph if you have a lower power setting and lean aggressively. Then you don't touch the mixture during your descent for a landing at sea level. You do an unexpected go around, jam full throttle in, and your engine will still get close to 8 or 9 gph. That's probably close to peak EGT, if not slightly lean of peak, but will still work fine and produce plenty of power.

Basically, I know what you're cautioning against in theory, but I can't think of a real world scenario where it would actually happen.

Also, I should reiterate, I agree with you for doing go arounds from higher altitudes. I'm only talking about sudden, quick go arounds close to the ground.

And I'll even share one other scary detail--a lot of times I leave the prop lever pulled back and mixture leaned out all the way to landing. As in, when other pilots say to advance them on short final, I just let 'em be. I'm a real cowboy like that.
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What is a real world scenario out side of the flare where everything is forward already that you don't have time to do all three? Just curious.

OMG OH TEH NOES YOU DIDN'T PUT THE PROP FORWARD AHAHAHAHAH:panic::panic::panic::panic::panic::panic::panic:lol

I actually don't have a problem with that at all if its a conscious decision not to, just as long as you're deciding how your going to fly the airplane, and not just forgetting to push the levers up.
 
Stomp16 said:
The patterns are fine and the distances are correct. However, the 206's tend to drop like a rock. You can fly a perfect pattern(concerning distance) and not correct for the tailwind. Once that 30kts ends up off the nose and without a correction of power, you'll be well short of the runway.
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Yep, and if you turn so that it won't you'll have to either fly a ridiculously wide pattern, or turn so tight that your pax soil themselves (probably more than 30 to 40 degrees of bank). Most hiperformance singles seem to be like this. The 206, 207, PA32 (all three, the lance, the toga, and the Cherokee 6) all seem to exhibit these traits.
 
Stomp16 said:
The problem comes when people slam power back in without first backing off the rpms.
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Not quite sure what you mean?

Bottom line (the way I fly it) when we got a strong easterly at SZP, and I am in anything, I turn my base downwind abeam the touch down point. I still use the same amount of bank as normal days, and let the excessive ground speed make up for the rest. I usually don't have to add any power get to the runway, and adjust flap usage to make sure my glide path looks right. I am not saying anyones technique is better or worse, I am just pointing out that if you had to add a bunch of power to get to the runway because you advanced props, something should have been changed about the approach.

I am of the school of thought to have it ready when I need it, and I don't want any config. changes when it's time to do a go around, or on short final. Concentrate on making the landing, and leave everything else alone. If it wasn't configured on short final, go around and try again. The last thing I want to do, is throw the props forward, mix.'s fwd., hit a bump, and accidently knock one of the levers back, like the mixture or prop, and create a situation that was pilot induced, and totally avoidable.

Bottom line is, it does not matter how you get there, it just matters that you do.
 
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