When do you advance props

vikingair

vikingair

Well-Known Member
I'm just curious when you've been taught/teach during approaches/landings to set the prop controls full forward AND why? My understanding is the the purpose is to ensure maximum power/efficiency should the need arise to go around.

From a mechanical standpoint it seems that the prop control can be moved to the full fwd position at anytime insomuch as its done AFTER a power reduction to prevent overspeeding/excessive RPM and BEFORE the addition of full throttle. How about from an operational/SOP standpoint?
 
I was taught not to go full forward unless airspeed is below 100.
Props go full forward on short final. "Props full froward, 3 green"

I know the Beech1900 checklist we used said to advance props when landing is assured.
 
vikingair said:
I'm just curious when you've been taught/teach during approaches/landings to set the prop controls full forward AND why? My understanding is the the purpose is to ensure maximum power/efficiency should the need arise to go around.

From a mechanical standpoint it seems that the prop control can be moved to the full fwd position at anytime insomuch as its done AFTER a power reduction to prevent overspeeding/excessive RPM and BEFORE the addition of full throttle. How about from an operational/SOP standpoint?
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I was taught to do it after reducing power abeam the numbers in the pattern, because...well, that's just the way my commercial instructor taught it. I think his logic was to do it sooner rather than later in order to prevent forgetting it during a go around.

I now teach to do it when initiating a go around because that method seems simpler, easier, and quieter to me. The performance lost and extra wear on the mechanical components by doing it at this time is negligible as far as I can tell.

Of course, if a pilot wants to do it at another time, I don't really care as long as they have a reason for doing it the way they do. It's not a big deal one way or the other.
 
I was taught to go full forward on the props during the GUMPS check, but more specifically on the downwind leg of the pattern or before the FAF on an IAP.

It really comes down to personal preference and POH instructions. I got in trouble with props full forward on my initial CFI ride. I passed, but the examiner DID NOT like it when I went full forward. He had me sit on my hands and showed me how he did it. Basically once you cleared the fence for the runway was his instruction. His reasoning is that it will create drag, etc.
 
Here is the GUMPFS check I teach:

Gas - On the proper tank, plenty of it, boost pump on.
Undercarriage - Handle in the down position (positive gear indication depending on system)
Mixture - Set the way we need it (a mooney flyer habit since full mix causes backfiring)
Props - full forward on final.
Flaps - fully deployed (or as required)
Seatbelts - check

I developed my GUMPFS check after many hours of flying my mooney around and finding what was best for me. There really isn't a mechanical reason why I put the prop forward on final, just a procedural one.
 
I prefer to have them go full forward on very short final. If you go full forward at say the abeam point and it's a gusty day out, you may find that you might need to add a lot of power once turning final. Depending on how bad the wind is, you may over speed the prop. Therefore I wait until landing is assured.
 
CCGUMPS check anyone?

Carb heat (if equiped)
Cowl Flaps (usually closed)
Gas (Both or fullest tank depending on model)
Undercarriage (down, verify with hand on selector and gren light['s])
Mixtures (set)
Props (high rpm, for most power if needed)
Seatbelts and Switches (everyone buckled in, aux pumps if required, lights on)

I guess it's a matter of personal preference, but this get's done when entering the pattern, when down wind abeam of touch down point, when turning base, when turning final, or if on approach, when crossing FAF/glide slope intercept, and at 100' before MDA/DA. I know some say it's hard on equipment to go full throttle with the props @ high RPM, but I can think of a few reasons why it would be harder on equipment to not. One in particular, when I am doing a go-around, and on engine quits, I am assured full power out of my only good engine, with fewer steps to get me there. And, correct me if I am wrong, but you would only have to be worried about being hard on parts if infact you did have to do a go around. Saftey trumps being nice to equipment.
 
G
U
M
Prop later
S

I usually try to put them full when the governor can't change the pitch any further. I don't know why but I don't care for the audible change.

In the bonanza though I typically just roll the prop forward while turning final. I don't know why but that airplane you have to be at a extreme reduced power setting not to get the engine to surge up when putting in the power.
 
Stomp16 said:
Depending on how bad the wind is, you may over speed the prop.
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Just to clarify, if the aircraft is maintained properly, a person won't technically "overspeed" the prop by adding power during an approach with the prop levers forward. If they could, they'd be overspeeding the prop on every takeoff, as well.

Now, if you're talking about the very loud, annoying 2700 rpm or whatever the aircraft is rated for, that's entirely possible. But it won't damage anything in the way a true overspeed condition could.
 
I wait until very short final. I do a GUMPS check when turning final, or when on a few mile final, then do it again on short final. I can sometimes be obsessive compulsive with my GUMPS check, but I'll be damned if I accidentally land gear up......

Like Stomp said, I've added it too early before and had to add power.
 
jrh said:
Just to clarify, if the aircraft is maintained properly, a person won't technically "overspeed" the prop by adding power during an approach with the prop levers forward. If they could, they'd be overspeeding the prop on every takeoff, as well.

Now, if you're talking about the very loud, annoying 2700 rpm or whatever the aircraft is rated for, that's entirely possible. But it won't damage anything in the way a true overspeed condition could.
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True. I should have clarified. Over-speed was the wrong wording. However, there is no reason for the rpm's to red line during an approach to land before a go around is initiated. Bit of a pet-peeve of mine picked up while doing company checks.
 
Props go forward on a very short final with the low power. I prefer keeping it as quiet as possible. i.e. no audible change
 
My method is to run GUMPS when entering downwind but leave the prop out of it. Than when I retard my throttle at the numbers I will push the prop in. I do this just to keep it from redlining
 
Stomp16 said:
True. I should have clarified. Over-speed was the wrong wording. However, there is no reason for the rpm's to red line during an approach to land before a go around is initiated. Bit of a pet-peeve of mine picked up while doing company checks.
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Do you not take off with props full forward with power max/top of green arc/or whatever your gauge says max power is?
Are you saying that there is too much "stress" by going max rpm?
Twin Commander?
 
BajtheJino said:
Do you not take off with props full forward with power max/top of green arc/or whatever your gauge says max power is?
Are you saying that there is too much "stress" by going max rpm?
Twin Commander?
Click to expand...

Yes, the prop(s) are full forward on t/o (supposed to be anyways). :D However, I see no reason for the prop(s) to be red-lined during a landing. More than likely it's not going to hurt anything but IMHO, it's poor engine management. I see people go prop full while abeam their landing spot with a 30kt tailwind and then guess what happens when they turn base, then base to final? 8-10inches of mp get slammed back in because they are suddenly not going to make the runway with the configuration they have. Along with that comes the red-line of the engine which all could have been prevented with a bit of forward thinking. I'm not here debating whether or not it hurts the engine, I'm here talking technique.

Twin Commander........I wish. :cool:
 
I make sure to put my props full forward only after I squared my manifold pressure off to meet it to help prevent shock cooling.
 
For those who dont go full till final doesnt this mess up your glide. The reaosn I always went full at the numbers after pulling the power so that I got that increase of drag right away and could compensate for it instead of putting it in on short final and all the sudden having a increase in drag that will cause me to come up short.
 
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