Power settings

[baldk9 3]

In the performance section of the manual ALL the power settings are given with the rpm settings at 2200 rpm. Other turbine equipped aircraft I has used in flight sim have always reduced rpm when reaching cruise. My question is: is this particular to the PA46T or an oversight in the manual? I have used different settings in cruise and have reduced the rpm setting down to 1900 and saw no deay in flight performance and improvement in fuel burn.

[ottor 0]

You'll find some answers in this thread.http://forum.avsim.n...ost__p__2225652

[dusty_sourdough 8]

Gunny, this is a from a post here in the forum:All credit goes to Kurt "Yoda" Kalbfleisch for this info...The only time you would normally have the props at max RPM is when the gear is down...takeoff and on final approach. After takeoff, you should pull the prop back to 2050 rpm. The technique I've seen recommended is to takeoff with 1000 ft/lbs torque and max RPM, then once the gear and flaps are up, pull the prop back to 2050 rpm and increase torque to 1200 ft/lbs for the initial climb. Keep in mind the ITT red line of 690 degrees C, and don't exceed that.As you climb, the torque will fall off, so advance the power lever to maintain 1200 ft/lbs (or as close to it as you can get without exceeding the ITT limit). Climb at 140 KIAS, adjusting power as I've described, and controlling airspeed with pitch or by adjusting the vertical speed on the AP.At cruise altitude, you can come back on the torque to between 600 and 900 ft/lbs. Economical cruise is always going to be 600 ft/lbs torque, but in the real plane, the cabin heat and defrost run off the engine so at higher flight levels, you'll be more realistic if you run at 800-900 ft/lbs.Leveling off in cruise, keep in mind that the faster the prop is turning, the more noise it makes, so you will want to pull the prop rpm back. This will give you a speed increase, and decrease fuel consumption...like putting your car into a higher gear. Watch the engine limits as you change things, and keep the torque at the desired cruise power. Also, watch the airspeed and don't exceed the red line on the airspeed indicator.Descending with a turboprop is really easy -- you pull the power back as far as you want and descend. It works well if you pull the torque back to 500 ft/lbs and control the airspeed with pitch. You'll have to adjust the power lever to maintain 500 ft/lbs as you descend, but you'll have your power set for the approach when you get down to the IAF. Bernt will have to chime in on this for the Carenado P46T as I haven't tested it yet, but in a real turboprop, pushing the prop lever full forward while descending is like popping open a big speed brake. I've read that you can get as much as 4,000 fpm in the descent in the P46T this way.There's a lot of helpful info at www.pa46t.com.The only other question I'll address is the ice deflector: The PT6 air inlet is actually at the rear of the engine, so there is a bend in the air intake duct. At the bottom of this bend, there's a door to the exterior that can be opened and closed, and inside the duct, a vane that can be extended to further "bend" the air flow in the duct. When the vane is extended and the door open, any particles (like ice) will be deflected out the door instead of passing all the way to the engine inlet. It's pretty common practice to run with the ice deflector on/open while taxiing to help protect the engine from FOD. When the deflector is on, you should see a decrease in power, since the volume of air going to the engine inlet is reduced.Edit: Mods, you can remove my post, as the above poster beat me to the reply.

Edited January 17, 2012 by dusty_sourdough

[baldk9 3]

Thanks Dusty lot of good information and interesting website. Must have cost him a pretty penny to convert it and upgrade the interior. Thanks again

[dusty_sourdough 8]

Oh yeah, a fortune for all that work on the plane.Planes are definitely money pits.You're welcome Gunny.