How to fly a fuel injected airplane with a CS prop

Groundpounder

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Emerson Bigguns
Kind of a stupid, basic question, but I am going to start flying for fun an airplane with a constant speed prop and fuel injection soon. Despite having 5000 hours, I have no time in a piston aircraft with fuel injection, and I haven't flown an airplane with a CSP since I got my ATP. What do I need to remember? Is there anywhere on line that gives a good breakdown of how to fly an airplane with this configuration? I'm gonna have a full checkout in this airplane, but I want to get ahead of the power curve, no pun intended.
 
Best bet is to get a copy of the POH and read that. Every airplane is different. On mine the prop control stays set at 2500 rpm all the time unless I really need to slow down.
 
what plane? an hour or two with a CFI and you'll have it down. prepare to get aggravated with hot starts. I'll say 'typically' (meaning there's always someone who does it differently) when you INCREASE power, go mixture, prop, throttle. when you DECREASE power, go throttle, prop, mixture. I know you don't necessarily HAVE to do it that way, and someone will come along with some bizarre plane that you can't do it that way, but in a typical complex plane that makes the most sense and is an easy flow.

↑ MPT
↓ TPM
 
The biggest thing I would stress is knowing what you’re actually setting/controlling with the prop lever. You are setting RPM, you are not setting a prop blade angle.

Remember that you need to set both manifold pressure and RPM to get a desired power setting. Depending on the altitude you’re flying at you may be able to get that power setting with several different combinations.The aircraft flight manual should have a power setting table that will help you select an acceptable manifold pressure and RPM combination to make the desired power.
 
Kind of a stupid, basic question, but I am going to start flying for fun an airplane with a constant speed prop and fuel injection soon. Despite having 5000 hours, I have no time in a piston aircraft with fuel injection, and I haven't flown an airplane with a CSP since I got my ATP. What do I need to remember? Is there anywhere on line that gives a good breakdown of how to fly an airplane with this configuration? I'm gonna have a full checkout in this airplane, but I want to get ahead of the power curve, no pun intended.

Keep the Prop on Top.

EDIT: It’s not that simple of course
 
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Keep the Prop on Top

Let's not subject an open mind to unnecessary old wives tales. If the CFI checking you out uses the phrase "over-square," other than in the sentence "over-square is an old wives tale," just smile and ignore him.

Same goes for the advice about regarding the "flow" of power changes. The whole "mixture prop throttle" flow for power increases is rooted in the bogus idea that the manifold pressure should never exceed the RPM (over-square, "prop on top," nonsense).
 
Let's not subject an open mind to unnecessary old wives tales. If the CFI checking you out uses the phrase "over-square," other than in the sentence "over-square is an old wives tale," just smile and ignore him.

Same goes for the advice about regarding the "flow" of power changes. The whole "mixture prop throttle" flow for power increases is rooted in the bogus idea that the manifold pressure should never exceed the RPM (over-square, "prop on top," nonsense).

Agreed. Post edited. Just meant as a quick basic thought provoker.
 
Kind of a stupid, basic question, but I am going to start flying for fun an airplane with a constant speed prop and fuel injection soon. Despite having 5000 hours, I have no time in a piston aircraft with fuel injection, and I haven't flown an airplane with a CSP since I got my ATP. What do I need to remember? Is there anywhere on line that gives a good breakdown of how to fly an airplane with this configuration? I'm gonna have a full checkout in this airplane, but I want to get ahead of the power curve, no pun intended.

What plane?
 
One the prop is figured out, the next is getting to 50 degrees lean of peak on the engine monitor.
 
don't forget to put a couple cases of water in the back.....it'll help your carrier deck landings. :D

keep the CHTs below 400 and preferably lower than 380F and your engine will thank you. There are two schools of thought to perform this....one is very rich....+120 deg from peak EGT or on the lean side...at least 20 deg lean of peak EGT. Now once you're at altitude (+7,000 feet) lean till rough then richen for best power....at that altitude or higher you'll be at 75% HP or less and can do no wrong leaning.
 
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...Same goes for the advice about regarding the "flow" of power changes. The whole "mixture prop throttle" flow for power increases is rooted in the bogus idea that the manifold pressure should never exceed the RPM (over-square, "prop on top," nonsense).

got anything else to offer other than 'nonsense'? my recommendation is based on flow, not some old wives tale, and has served me well 100% of the time. nice and easy, not based on anything other than that.
 
Don't see how these are related to each other, having fuel injection is irrelevant to how a constant speed prop is used. Only thing FI does is change the engine start technique, and this will be described in the POH.
 
Oooh, I see that the over-square button has already been pushed. Next to be endlessly debated is fuel-injected hot starts.
 
The biggest thing I would stress is knowing what you’re actually setting/controlling with the prop lever. You are setting RPM, you are not setting a prop blade angle.

The other big concept is a CS prop simply allows you to have a climb prop for takeoff and climb, and a cruise prop once you reach altitude.
 
Don't see how these are related to each other, having fuel injection is irrelevant to how a constant speed prop is used. Only thing FI does is change the engine start technique, and this will be described in the POH.

nobody correlated the two. he just asked about them both.
 
got anything else to offer other than 'nonsense'? my recommendation is based on flow, not some old wives tale, and has served me well 100% of the time. nice and easy, not based on anything other than that.

It's simply totally unnecessary. In most complex airplanes, you can just set the prop at 2500 and leave it there. Need to increase power? Use the throttle. Need to decrease power? Use the throttle. Screwing around with all three levers every time you need to make a power change is over-complicated and totally unnecessary. Sure, on rare occasion you may need to tweak the blue or red lever after making a power change, but certainly not EVERY time.
 
It's simply totally unnecessary. In most complex airplanes, you can just set the prop at 2500 and leave it there. Need to increase power? Use the throttle. Need to decrease power? Use the throttle. Screwing around with all three levers every time you need to make a power change is over-complicated and totally unnecessary. Sure, on rare occasion you may need to tweak the blue or red lever after making a power change, but certainly not EVERY time.

I never said 'every time' and I never said you actually have to move all the levers every time.

OP, think of it this way...……

if you were in a Cherokee or 172...you start up the plane, you lean it out (you DO lean it out for ground ops, don't you?). you do your other stuff, you taxi, you're ready for take off. do you firewall the throttle, then enrichen the mixture? NO, you don't. you'd say "mixture rich, full throttle". so in that case, you are increasing power, you are doing the same thing, Mixture, then Throttle. now throw a prop in the middle of that (literally) and your flow it 'mixture rich, prop full forward (you wouldn't mash the throttle THEN check the prop, would you? NO, although it wouldn't be a huge deal, it just doesn't make any sense from a flow perspective) then full throttle. so, ↑ MPT.

just because you aren't physically moving levers doesn't mean you don't still have a flow check....in brads example something like "I was told to climb, so full throttle, prop can stay where it is, mixture can stay where it is". flows, that's all.

of course once you understand what everything is doing, it all becomes second nature and most of this goes out the window anyways. my flow SUGGESTION was to hopefully just make it easier to learn in the beginning.
 
Does the airplane in question have cowl flaps?
 
Copy the table in the POH, print it out and stick it to the back side of the sun visor. There are a thousand ways to hot start a fuel injected engine and I'm not going to go into that. All I'll say is find out what works best for a particular airplane and go with that. Brush up on your swearing vocabulary, you're going to need it.
 
PA-32-300

I'm sure your memory has been well jogged by now of the basics. I'm pretty sure there are some PA32 owners around here. Hopefully they will find this and give you some details. Or maybe someone who knows who they are will @ page them
 
Read the POH, a 5k ATP shouldn’t have any trouble with a PA32
 
Kind of a stupid, basic question, but I am going to start flying for fun an airplane with a constant speed prop and fuel injection soon. Despite having 5000 hours, I have no time in a piston aircraft with fuel injection, and I haven't flown an airplane with a CSP since I got my ATP. What do I need to remember? Is there anywhere on line that gives a good breakdown of how to fly an airplane with this configuration? I'm gonna have a full checkout in this airplane, but I want to get ahead of the power curve, no pun intended.

Never let the black handle get ahead of the blue handle and you'll be fine.
 
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don't forget to put a couple cases of water in the back.....it'll help your carrier deck landings. :D

keep the CHTs below 400 and preferably lower than 380F and your engine will thank you. There are two schools of thought to perform this....one is very rich....+120 deg from peak EGT or on the lean side...at least 20 deg lean of peak EGT. Now once you're at altitude (+7,000 feet) lean till rough then richen for best power....at that altitude or higher you'll be at 75% HP or less and can do no wrong leaning.
I go 50deg rich of peak in a 182..I’m i doing this wrong?? I don’t have engine monitor just EGT. I just worked this procedure out
 
I go 50deg rich of peak in a 182..I’m i doing this wrong?? I don’t have engine monitor just EGT. I just worked this procedure out
not rich enough...IMHO. 50 is at the peak of the CHT temps....it needs more...like +100 rich of peak.
pp77-landmarks.jpg
 
PA-32-300

When I transitioned to the Lance, I read Jim Deakins' Pelicans Perch articles about engines on AvWeb. It was very helpful.

For most x-country flights, its pretty simple -- takeoff at wide open throttle (WOT) and prop at high RPM. Shortly after pulling up the gear I pull the prop back slightly so I'm not whining too much at the neighbors. At cruise, prop comes back to 2400. I cruise at WOT (normally aspirated engine). That's all that happens to the throttle and prop until I descend. On descent, its some combination of pitch and throttle depending on the situation until I'm ready to slow to approach/pattern speed which is about 17" and 2100 rpm. I generally mostly don't push the prop forward in anticipation of a go around (I push it forward when/if going around). That's about it. Have fun.

Enjoy the power off glide of the PA32! :)
 
I go 50deg rich of peak in a 182..I’m i doing this wrong?? I don’t have engine monitor just EGT. I just worked this procedure out

I was told 100-150 rich of peak. I turn the red knob in so I get 4-5 tick marks cooler than peak (each tick to represent 25 degrees). Borescope shows my valve faces have not been getting too toasty. I’ll keep it up.
 
I was told 100-150 rich of peak. I turn the red knob in so I get 4-5 tick marks cooler than peak (each tick to represent 25 degrees). Borescope shows my valve faces have not been getting too toasty. I’ll keep it up.
Sheesh. Glad I haven’t done this too much. But for my altitudes usually less then 10k that lean is not going to be much to be that rich of peak. Have a cross country coming up will plan to get high and work on this. Thanks. I only think about leaning at altitudes greater the 6K.
 
Everyone has an opinion on LOP vs ROP and everyone is convinced they are right. If you are borrowing the airplane, the owner's technique is now your technique...

It's not rocket surgery, you'll be fine. Welcome back to props.
 
Read the Pelican Perch articles referred to above, about leaning technique. Keep them handy. Basically anything that you read here is just going to be people misremembering part of the information from those articles. Read the POH and study the checklists for climb and cruise and the power setting tables. I prefer to choose a lower RPM setting whenever possible, with the throttle wide open as long as I’m at an altitude that allows it. But any power setting that the POH tells you to use is going to be fine.
 
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