PPRuNe Forums

PPRuNe Forums (https://www.pprune.org/)
-   Private Flying (https://www.pprune.org/private-flying-63/)
-   -   PA-34 power setting sequence (https://www.pprune.org/private-flying/555075-pa-34-power-setting-sequence.html)

cavortingcheetah 27th January 2015 18:13

At the risk of sticking my neck into somewhere I haven't been for a while, might I suggest that power settings used at a twin training school are not necessarily those that would be used in real time by a charter pilot quite correctly handling the engines on the same machine.

Cows getting bigger 27th January 2015 19:18

My day job is spent sitting between a couple of TIO-540-J2BD engines, each capable of pushing-out 350HP. The thought of reducing RPM before MP scares me. :eek::eek::eek:

Big Pistons Forever 27th January 2015 19:23

Flight training procedures should be 100% in accordance with the POH. An important part of all training, but especially, advanced training is inculcating students with the importance of understanding all of the aircraft systems and knowing what the expected performance should be for every phase of flight.
The only way this can be achieved is by integrating the POH into every lessons.

With respect to piston twins and charter flying I have had to beat out the stupid " flight schoolism " from numerous new hires. Why can't the school just teach it the right way from the beginning ? :ugh:

Tigger_Too 30th January 2015 07:04

Rev up. Throttle back

Ellemeet 2nd February 2015 05:32

In my turbocharged commander 114tc (se) max take off power is 39/2575.

Once airborne over 1000ft agl I will go to high climb power 35/25 .. Later I will go to normal climb power 30-31/24

Cruise is 29-31/22-24.

Square on a turbocharged piston in this category? I think not.. Only at approach speed. 23/23 gives 120kts.

I allways reduce throttle first. The reason is that when you reduce rpm the mp will always rise a bit. You do not want to do that when you are already at max.

The other thing is that its the easy way to work the flow from left to right .. First throttle, then rpm, then the fuelmix

englishal 2nd February 2015 07:59

Same in my commander, except O/B is 42" MP.

So I normally use 40" on take off (which can be fun jiggling the throttle on the take off roll as you normally get an increase in MP as the roll gets faster), once the flaps are up reduce to 36" and leave prop full forward for the climb (as per the POH). At TOC MP back to 31" and RPM back to 24" for a fast cruise.

eddygordo_86 25th September 2016 10:59

Seneca V
 
Hello guys

Taken from Seneca V POH:


4.29(k)
When power is reduced for descent, the mixtures should be enriched as altitude decreases. The propellers may be left at cruise setting; however if the propeller speed is reduced, it should be done after the throttles have been retarded. Cowl flap should normally be closed and the T.I.T should be maintained at approximately 1300F or higher to keep engines at the proper operating temperature. Set the altimeter. Adjust the windshield defrost as required during descent.

Hope it helps.

9 lives 26th September 2016 23:25


however if the propeller speed is reduced, it should be done after the throttles have been retarded.
Wow, that's awkwardly worded! As all Piper Seneca engines are direct drive, the propeller speed is the engine speed. As you retard the throttles, and the propellers reach the fine pitch stops, they [engines] will slow in relation to the throttle position.

Yes, you can further reduce RPM by selecting a more coarse propeller pitch, though I cannot think of any reason to do this in a twin, other than to stretch a glide after a dual engine failure. Having the props selected to coarse with the power is very low is generally harmless, unless you suddenly advance the throttles (like to go around). If you advance the throttles with the prop levers well back, it will be very quiet still, and rapidly become very expensive.

I can't imagine what Piper envisioned when they wrote that, but I would avoid doing it without a profound understanding of engine operation, and a compelling reason. An engine operating at maximum RPM is noisy, but it is protecting itself from detonation. Reducing RPM while maintaining the power setting is taking you toward detonation conditions, and you will only find out afterward that you were there, with a maintenance bill or engine failure.

Parson 27th September 2016 09:08

Throttle back, rev up except for;

setting climb power
levelling off in the cruise

foxmoth 28th September 2016 08:17


fI believe that my instructor is extremely professional and maybe he has a bit different considerations, which I don't understand at all
Why not ask him? Refer him to this thread if needed.

oggers 28th September 2016 21:42

https://youtu.be/yWS3_08YHR0?t=32m20s

Piltdown Man 29th September 2016 16:30

I'm with tmmorris -.RTFM. I really don't care what schools teach unless they teach what is in the manufacturer's AOM. Far too often rumour, heresay, personal foibles and hobby-horses and down right ignorance get in the way of the correct way of doing things.

PM

BigEndBob 1st October 2016 18:38

Been a while since I have flown PA34 but could the reduction of rpm to 2500 cause the MP to drop to a suitable climb MP setting like 35".
I know when I first went on the PA34 throttling back would drive me nuts as reducing the rpm caused the MP to drop and needing resetting. (Turbo slowing down).
I know we teach TPM to reduce power but does reducing rpm first to 2500 cause the MP to drop say 35".
If throttle comes back to 35" first, then pitch to 2500 does the MP drop below 35 requiring resetting?
Can't remember since not having taught on them for 15 years since the CAA killed of multi rating to mortal souls.


All times are GMT. The time now is 15:40.


Copyright © 2026 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.