New O3 driver looking for cruise power settings

[vasco]

i am a new O3 driver and am wondering what most are using for cruise power settings.  i would like to run LOP.  Thanks!

[piperpainter]

Mitch has an Ovation...MITCH Were are you!!!! He'll be along soon!

[roundout]

I use full throttle/2700 to climb, leaning to keep the EGT in the white band on the G1000 EGT gauge. Upon reaching my cruise altitude, 6-10k usually, I will bring the prop back to 2400 and back the MP off of full throttle 1" on the MP indicator. I then use the analyzer, usually with lean assist, to find peak and either go 150ROP or 50LOP. 150ROP will usually yield around 180kts in an OV3 at 2400 or 2500. The speed picks up with 2700 but I don't like the vibration or noise. Fuel flow is also much higher at 2700. At 50LOP you will be in the low 170s or so. Usually the difference between 150ROP and 50LOP at a given power setting and altitude is 5-7 knots. Fuel burn should decrease about 5gph. 

I flight plan an Ovation at 175kts/13gph and am happy when it does better than that. Aircraft without air or TKS will be a bit faster and I plan 180 instead of 175. 

[vasco]

Thanks!!

My transition instructor suggested reducing the prop to 2500 after 500 ft agl.  i will try 2700 on my next trip.

Have you ever tried "the big pull"?

[roundout]

I prefer to lean slowly in an Ovation because depending on the temperature, altitude, etc, peak EGT is going to be different every time you fly. In a turbo airplane peak is always going to be the same at a given power setting so you can do the BIG PULL every time and get it right. You won't hurt anything if you spend 30 seconds peaking it out. If you look in the Ovation 3 STC paperwork there is nothing prohibiting continuous operations at 2700 RPM. Besides, with a 1000fpm climb rate you're not using 2700 very long, anyway. 

[vasco]

Thank you.

[L. Trotter]

Perhaps someone can explain the 310HP STC POH supplement.

Supplement......Climb at RPM-2550, MP-24, yet, no restriction are placed on continuous cruise power at RPM 2700,

Multiple pilot recommendations......Climb RPM-2700, MP-Full Throttle. Then Cruise power as desired (typically RPM 2400, MP as desired).

So, is it engine safe/wise to use a continuous 2700 RPM in all phases of flight-particularly Climb (assuming temps remain OK)? 

[StevenL757]

2550RPM is the recommended cruise RPM at 40-50 LOP.  You will note a small decrease in airspeed from 2550 to 2400 or 2500, but no appreciable fuel savings, so best keep it at 2550 in cruise and descent. 

[Mcstealth]

Lancecasper is another one to ask.

 

 

[carusoam]

Gent's are we answering a question that is 6 years old....?

It has been years since Vasco stopped by last.

I do appreciate your enthusiasm though.  Makes me want to review where I'm at lately. 

Best regard,

-a-

[Hank]

5 minutes ago, carusoam said:

Gent's are we answering a question that is 6 years old....?

It has been years since Vasco stopped by last.

I do appreciate your enthusiasm though.  Makes me want to review where I'm at lately. 

Best regard,

-a-

Holy necropost, Batman! Have we been hanging around here that long???

Edited March 28, 2016 by Hank

[Marauder]

Gent's are we answering a question that is 6 years old....?

It has been years since Vasco stopped by last.

I do appreciate your enthusiasm though.  Makes me want to review where I'm at lately. 

Best regard,

-a-

I don't think so. L. Trotter asked a different question based on the 6 year old original thread. And besides not all of us have been here 6 years or more

[carusoam]

OOOOOOh,

I get it, now.  (Thank you Marauder, so many trees, I couldn't see the forest...)

1) The coolest part of the STC, is the author.  His engine knowledge is real.

2) The second coolest thing is the strength of the IO550's original design.

3) The third coolest thing is the climb rate, or the T/O roll, or....

4) The fourth coolest thing is it's ability to deliver 2550 rpm.  Not much different than operating the pre STC IO550.

Having a conversation with the author of the STC is priceless.  (Be ready to take good notes)

Best regards,

-a-

[Jeff_S]

No one has really answered the "revival OP's" question about operations at 2700 RPM.  While not perhaps recommended, yes, you could operate at 2700 RPM continuous as long as you are very careful to stay within mixture guidelines and manage CHTs correctly.  Engines are rated to go to TBO at their full rated RPM.  The performance charts in the STC clearly don't recommend this, but if you look through all the documents in the STC it does state that the engine is rated for 2700 RPM continuous.

But it would be a stupid thing to do because you'll be burning a ton of extra gas for not much more speed, and the equivalent wear on the engine will be greater. So unless you were up high and needed the extra HPs, probably not a good choice.

[carusoam]

Another small downside of the 2700 rpm regime is the sound level that comes with it.

Best regards,

-a-

[StevenL757]

5 hours ago, Jeff_S said:

No one has really answered the "revival OP's" question about operations at 2700 RPM.  While not perhaps recommended, yes, you could operate at 2700 RPM continuous as long as you are very careful to stay within mixture guidelines and manage CHTs correctly.  Engines are rated to go to TBO at their full rated RPM.  The performance charts in the STC clearly don't recommend this, but if you look through all the documents in the STC it does state that the engine is rated for 2700 RPM continuous.

But it would be a stupid thing to do because you'll be burning a ton of extra gas for not much more speed, and the equivalent wear on the engine will be greater. So unless you were up high and needed the extra HPs, probably not a good choice.

Exactly.