In Flight prop operation

[BryceKat 125]

Hey Leni and anyone else using an in flight adjustable prop (ifap) and mixture control(mc) on a 582,

How do you set your power in flight for cruise?

I have a gsc ifap and a Green Sky mc on my 582 powered mkiv.

I take off full rich full rpm 6700-6800 rpm, at 500 ft agl i start backing rpm down to 6200 until cruise altitude of 1500 ft agl, push over the nose and let the airspeed build, managing the rpm mostly with prop control to maintain 6000 rpm, and at this point back out some throttle, about 6 turns from full throttle (what i did w/ the fixed pitch before installing the ifap), and as airspeed builds, manage rpm w/ ifap pitch control. Once at a stabilized airspeed and altitude, i lean the mixture to 1100-1150 egt.

I have thought about leaving the throttle wide open and just using the ifap to control rpm and mc to reduce fuel burn.

My question is, how do you operate your engine, ifap, mc system? What do you think of leaving the throttle full open? Thanks for your input, Bryce

BTW: I baffled my radiators, mkiv style, and opened up the cowling outlet and installed a new trip strip so that my water temp never gets over 180 degrees.

[akflyer 1427]

Hey Leni and anyone else using an in flight adjustable prop (ifap) and mixture control(mc) on a 582,

How do you set your power in flight for cruise?

I have a gsc ifap and a Green Sky mc on my 582 powered mkiv.

I take off full rich full rpm 6700-6800 rpm, at 500 ft agl i start backing rpm down to 6200 until cruise altitude of 1500 ft agl, push over the nose and let the airspeed build, managing the rpm mostly with prop control to maintain 6000 rpm, and at this point back out some throttle, about 6 turns from full throttle (what i did w/ the fixed pitch before installing the ifap), and as airspeed builds, manage rpm w/ ifap pitch control. Once at a stabilized airspeed and altitude, i lean the mixture to 1100-1150 egt.

I have thought about leaving the throttle wide open and just using the ifap to control rpm and mc to reduce fuel burn.

My question is, how do you operate your engine, ifap, mc system? What do you think of leaving the throttle full open? Thanks for your input, Bryce

BTW: I baffled my radiators, mkiv style, and opened up the cowling outlet and installed a new trip strip so that my water temp never gets over 180 degrees.

Max TQ on the 582 is at 6500, so that is my take off power RPM. I keep WOT in till I level off and airpseed builds. I punch in more ptch to give me MAX RPM of 6450-6500 straight and level, then pull the power back. I know from lotsa hours that I can set up my cruise of 58-5900 RPM at 1150 on the EGT's and 5.4-5.6 GPM and my burn is clean and the engine is very happy. You can get it way lean if your just using pitch control and EGT to set the prop. If you lug the engine, it will lower the EGT's but it is really hard on the engine. Every once in awhile, I may get a wild hair and after I have the thing set up for cruise, I will go WOT and hold altitude to make sure I am set for max RPM of 6500. this seems to keep the engine and me very happy

[BryceKat 125]

Leni,

When you said,"You can get it way lean if your just using pitch control and EGT to set the prop", i don't understand. Isn't the main needle almost all the way out of the jet, letting fuel by? Then if you lean it by decreasing the pressure in the fuel bowl, less fuel comes out. Maybe this is the same as reducing the throttle?

Also, the difference in climb on my plane between 6800 and 6500 is very noticeable in the seat, i don't have a vsi. I have a field down in a bowl, its 90+ oat, and i like to eat, so i need all the umph i can get ! Thanks, Bryce

[akflyer 1427]

Leni,

When you said,"You can get it way lean if your just using pitch control and EGT to set the prop", i don't understand. Isn't the main needle almost all the way out of the jet, letting fuel by? Then if you lean it by decreasing the pressure in the fuel bowl, less fuel comes out. Maybe this is the same as reducing the throttle?

Also, the difference in climb on my plane between 6800 and 6500 is very noticeable in the seat, i don't have a vsi. I have a field down in a bowl, its 90+ oat, and i like to eat, so i need all the umph i can get ! Thanks, Bryce

I have the Arctic Sparrow Inflight mixture that actually raises and lowers the needles (they are threaded and screw in and out of the slide). I can lean mine out to a burn down if I want to in the mid range. Yours may not be adjustable enought to lean you down that far.

I am at sea level and cooler temps, but on floats, I know I get a better climb and more power to get out of the hole at 6500 than I do 6800, but that could be due to the different profile on the prop blades too. If 68-- work best for you, then by all means use it. Every plane is a little different!