Prop RPM during the approach. [Archive]

Chuck Ellsworth

4th Dec 2009, 02:09

I am going to move this discussion from the check list thread over here where we can discuss it as a stand alone subject.

I will first state that I do not increase prop RPM during the landing approach until I pull power off for the landing, then I push the lever/ s full forward. ( Or the pilot not flying does in a two crew device. )

Unless there is a need for increased RPM due to some unusual circumstance such as turbulence or airframe icing to name two possibilities I use the above procedure.

Here is why.

Increasing RPM on approach increases piston travel thus causing unneeded wear through friction in all piston engines.

Large piston engines are subject to reverse bearing loading caused by under squaring of power due to the airflow driving the engine thus causing reversing thrust loading of the bearings and counter weights.

When conducting an approach for a landing I am going down hill which requires less power than level flight, if I change my profile from descending to climbing I then select climb RPM followed by climb power I am hard pressed to think of a situation where there would not be time to smoothly perform these actions.

If a pilot gets into a situation where said pilot has to ram on take off power to salvage an approach or go around and does not have time to select the proper RPM for the power required it shows that said pilot was way behind the airplane thus displaying a serious lack of airmanship.

Having done tens of thousands of touch and go type flying using cruise RPM on the approach to power back for the touch down before increasing prop RPM, it has worked just fine for me.

protectthehornet

4th Dec 2009, 02:32

I can certainly understand your views...and even add that it is less noisy for all concerned.

But...I would still put my prop forward/high rpm and just fly that way.

I've seen two situations where all the advance planning and airmanship went the heck out the window and full power was needed.

Wind shear comes to mind and violent evasive action to avoid a crash/collision. so I hope these things don't happen to you...but I would rather be ready than not.

Dudley Henriques

4th Dec 2009, 02:49

Chuck;

Absolutely, and I would agree with your procedure which is mine as well. The subject of running up the prop at all, and WHEN and under WHAT CIRCUMSTANCES should exist when the prop is run up on final are two entirely different issues.
My procedure is exactly what you have stated as yours. You should be power BACK before running up the prop for certain. Anyone who has heard a pilot run up the prop on a T6 on downwind while at cruise power will attest to the immediate need to find a pair of good earmuffs :-))

The OTHER issue, and the important issue concerns LEAVING the prop (s) in cruise THROUGH the landing, and I am absolutely opposed to that.
DH

Chuck Ellsworth

4th Dec 2009, 03:00

Yes Protecthehornet I have heard the same opinions given over and over from pilots paranoid about the possibility of having to ram on full power due to an unexpected situation suddenly requiring full power.

With regard to turbulence you will note it is one of the times I will select higher RPM to help stabilize an approach, however should full power be required I am quite capable of pushing the prop lever/s forward with the throttle//s at the same time.

As to your concern for my safety I appreciate it and would like to point out that I have encountered some of the most violent turbulence one could imagine during the fifteen years I flew heavy water bombers in both N. and S. America and obviously my procedures for power handling have worked quite well as I never wrecked an airplane.

Power application to salvage a departure from controlled flight is a very risky crutch to rely on, I use energy conservation and try and stay in the safe speed regions of flight so inertia will give me time to safely use full power should I need it.

Once again may I express my opinion that planning ahead and flying the airplane with due regard for conditions negates the need to beat the hell out of my engines running them at an RPM that is not needed for the flight profile I am flying.

I am a firm believer in examining the outcome of a given method of handling power and the way I fly has worked safely for me during the past half a century of doing it for a living.

Smooth power handling will result in long engine life, compared to being a throttle jockey which can result in short engine life. :)

Dudley Henriques

4th Dec 2009, 03:03

protectthehornet;

I think we're finally getting straightened out here :-))

If the issue is WHEN to bring up the prop rather than WHETHER to bring it up at all, then power back and close in on final are the way to go .
Landing with the prop in cruise in my opinion is NOT the way to go.
DH

Chuck Ellsworth

4th Dec 2009, 03:12

Dudley Henriques

4th Dec 2009, 03:25

Dudley, you are correct that leaving the props in cruise during the landing is being a cretin.

If you read my posts you will note we both do it the same way, props/ s forward once power is reduced below positive thrust.

Lets use two airplanes that I have flown about ten thousand hours on collectively, the DC3 /C117 Super DC3 and the PBY.

On both airplanes I generally have the throttles fully closed before I get to one hundred feet to touch down, at that point the props are moved forward to full fine.

When I first received dual on the Pitts Special I had a difficult time leaving the prop and throttle full forward during the whole process of aerobating the thing and never did really feel at ease with running an engine like that.

I guess its hard to teach an old dog new tricks.http://images.ibsrv.net/ibsrv/res/src:www.pprune.org/get/images/smilies/evil.gif

We're definitely on the same page. I've spent a lifetime trying to teach pilots NOT to run their props up on downwind or even turning base. In the case of controlled fields with extended straight in's I leave um alone until my final GUMPS check which I teach others to make close in. Running the prop (s) up while still maintaining cruise MP has all kinds of issues associated with it not to mention the noise :-)
Right now I'm getting ready to do a presentation on display flight safety in Belgium where I'll be dealing with the high performance prop fighter go around situation.
The go around issue is in the works for this seminar if I can squeeze it in.
D

protectthehornet

4th Dec 2009, 05:38

so, there you are...reduced power as on approach and in this case, reduced prop rpm...if you do go to full fine/high rpm the first thing that happens is that you slightly increase drag until you bring up the throttle.

I used to work for a joint that had us ''stage cool' during the decent. what a difficult thing to do in real life, IFR, comply with ATC requests etc.
This was in light planes I should say.

just wondering how you might react to massive wake turbulence encounter at low rpm?

Listen, with your experience you will have no problem...but it is the young pilot with 200 hours or so that is asking for trouble

and then there is the turboprop...

mad_jock

4th Dec 2009, 08:07

In the UK it probably stems from the fact that most if not all CPL/IR's have been taught using staff examiner approved checklists.

I haven't seen one yet that doesn't have RPM up at the 1000' foot checks. (mind you I haven't seen many)

As for the reason why?

Gowds knows one of the RAF exCFS instructors will probably be able to tell you. I have a sneaky suspicion it will date back to WW2 aircraft.

Although I don't have a problem with what you say Chuck I suspect your (and your peers) capacity flying a VPP is far higher than most. The rpms up at 1000 above is just one more thing out of the way to allow full concentration on the last bit of the approach.

And turboprop its no great shakes if the RPM's are selected late but again you sometimes get a bit of lag on one side a bit of yawing, power changes etc. For very good reason the RPM's being up are included in the stable approach criteria. Apart from which the modern slippy TP's you will struggle getting the speed back to something sensible on a 3 deg slope.

irishpilot1990

4th Dec 2009, 09:21

I have always read checklists(proper ones that is) with a view there is a reason for every commad....and also there is a reason for its location.
Somebody somewhere messed up or missed something and hence the checklist order is to avoid these cock ups.
Full RPM is a check list command in a critical part of flight...so you should be doing it!!
you dont wait for the engine to cut out before you increase the mixture control!?!
It probably relates to windshear or engine failure situations.
that extra fraction of a second it take you to worry about the RPM lever could be difference in seeing your family at the end of the flight and not seeing them.Was it worth saving wear then?

DFC

4th Dec 2009, 10:00

Chuck,

You picked up on a general statement I made on the other debate and have given it a life of it's own thanks to you making an assumption.

The POH is the decider in all cases.

Some manuals require a specific (high / fine pitch) RPM to be set before / during the approach. Typical figures being 2500 or 2600 sometimes 2700.

It is impossible to set this RPM unless the prop is operating in the governed range.

Others don't. and it is up to the pilot to place the prop against the fine pitch stops at the appropriate time.

Most GA aircraft specify the power setting for climb as being Full increase RPM and full throttle. Note this is what the manufacturer has certified.

Therefore, in the absence of a specific RPM, the prop can be set to a fine setting after the MP has been reduced (typically to slow for gear and flap extension).

The average Student / PPL should not have to fiddle with controls on short final and should have one hand on the throttle and one on the stick for the final approach after the landing configuration has been established. The landing configuration being position of Gear, Flaps, Props and anything else that has a specific setting for landing.

ReverseFlight

4th Dec 2009, 14:39

Gentlemen, I totally agree with you. PUF check was the one I was taught (which amounts to the same thing ; I'm sure there're others):

Pitch - Full fine
Undercarriage - Down
Flaps - as required

Chuck Ellsworth

4th Dec 2009, 16:53

I knew this was going to be a subject that would result in most opinions being different from what I do for the simple reason that when people are taught a certain action to take during flight such as putting the props in full fine in the circuit and in most cases at a thousand feet that is what they believe is necessary.

However there are at least two of us here who do not teach nor do this and between the two of us we have been flying for over a hundred years so that should be at least worth considering.

Having asked every pilot I have done training with why they shove the prop lever/s forward so far from the actual landing I get basically the same answers which is that is the way it is taught, therefore it has to be the correct action to perform.

Maybe I am in the wrong forum here and should exit this discussion because the advice I am giving may be dangerous.

So lets dissect this one point at a time.

First lets make this perfectly clear that this engine handling discussion is about piston engine driven aircraft only.....and most of the airplanes that have propellers that are capable of pitch change that are used in flight training are basic light aircraft.

So I would like someone to answer a few questions I have concerning several opinions that have been put forward in this thread before the whole discussion gets all mangled into a state where no one can follow it.

I will first choose a comment by Mad Jock as my starting point in an attempt to find out if I have this all wrong and my method of power selection is wrong and possibly unsafe.

He said that the check lists he has seen asks for props up at 1000 feet above the landing area.

That would probably be down wind in a normal circuit.

Irishpilot1990 has the opinion that props should be moved to the full fine position as per the check list because you are in a critical part of flight and failure to have the prop/s in full fine may result in death should you need to increase power to arrest your rare of descent or go around and fractions of a second are critical.

O.K. lets examine the fractions of a second issue first.

When training pilots on heavy water bombers I had a demonstration that I used to show them that there is time to examine an emergency before taking any action that may be the incorrect action.

The demonstration was conducted to simulate an engine failure after lift off from the water and after VYSE plus five knots was attained which would generally be about two hundred feet above the surface.....a water surface.

I carefully briefed them that I would be failing the right engine at two hundred feet and at VYSE plus five knots and would be giving a voice warning " failing the right engine now " their only action at that point of time was to count to ten before doing anything period.

At the end of the ten count we would go through the engine failure on climb out procedures as laid out in the check list.

The object of this lesson was for the pilot being trained to note the airspeed decay during the ten count...that was " ALL " the trainee was to concentrate on.

Every time we did this demonstration the airspeed decay was " TWO KNOTS " after the ten count was finished which gave us a three knot safety margin above VYSE during the demonstration to that point in the climb.

My reason for offering the above demonstration was so we could better examine just how " critical " the beginning of an approach to a landing is time wise with regard to power changes.

I was training Captain in a water bombing company that operated nine PBY water bombers for twelve years and used that demonstration of inertia with each and every pilot being trained in said company...never was there any time where the speed decayed down to VYSE at the end of the ten count and never was there a problem in maintaining controlled flight and going through the engine failure on climb actions.

By the way I had a engine fail just at lift off with a full load of water one day and it was the critical engine, we had no problem maintaining control and feathering the engine and flew 75 miles back to our base on the other engine. Minus the load of water of course. :E:E

Any comments regarding how critical the begenning of an approach to a landing really is taking into consideration the above statements of fact?

Tinstaafl

4th Dec 2009, 17:23

Similarly to Chuck et al, I usually leave the prop in cruise RPM during the approach. At some point in the later part of the approach power will be low enough for the CSU to have the props on the fine pitch stops. Once that happens I advance the RPM levers to max. RPM. It's easy enough to tell - throttle movement has a direct effect on RPM.

Exceptions to the general procedure include icing (high RPM to fling off the ice), turbulence/shear sufficient to make me anticipate needing large power changes to manage the profile, or asymmetric leaving me with little excess power.

Chuck Ellsworth

4th Dec 2009, 17:24

Alister there is no problem removing your hand from the throttle/s when you close them and moving the prop/s lever/s to full fine as they are always close to each other in all airplanes.

Conversely if one is so focused on one task such as handling the flight controls during the final phase of the approach and landing that they are unable to perform any other task how do you recognize some other situation that may be unfolding?

Aviator part deux

4th Dec 2009, 19:44

Very interesting idea's stated here. In my brief experience I am intrigued by the idea of not setting yourself up for the worst case scenario, which for me would me having to execute a single engine go around in poor weather conditions. In my opinion, that is a best practice point and the best example to set to anyone your flying with, surely thats showing that you are ahead of the aircraft no?

Based on the scenario of a piston aircraft, normally aspirated or with a blower at either end of the stream. Surely anyone would want minimum workload, maximum power available when in the critical stage of an approach i.e. commital to land.

Now what has been discussed about engine wear especially with everyone trying to save pennies wherever possible I would tend to agree with you. However, as also stated wear has no price when it comes to safety!

One item for consideration which hasn't been broached is the type of aircraft everyone is flying, as we all know a lot of light twins for all intents and purposes may as well have 1.5 engines. Chuck writes about heavy water bomber experience, ok I take your point but remember the other people who are also reading this thread who do not have your depth of experience excuse the pun! I would interested to hear what peoples SOP is on the subject?

I'm a firm believer in reds blues three greens on final, I too want to go home to the lady and/or have a beer after I finish for the day!
(note: unless of course you have a fadec and only one stick to play with!) :ok:

Chuck Ellsworth

4th Dec 2009, 21:17

Alister what I am trying to explain is when changing from the approach attitude to the climbing attitude is the sequence of actions is pitch up, power up.

I have never seen a situation on an approach for a landing where one second lapse in action would be critical and result in an accident. ( This of course requires the pilots thought process to be ahead of the airplane on final, not back on base leg. )

If a pilot is overwhelmed by having to add one simple hand movement such as moving the prop pitch lever/s forward before or while moving the power lever/s forward then I would be very concerned about said pilots suitability to be in control of that aircraft.

Maybe my expectations are to high?

Big Pistons Forever

4th Dec 2009, 22:04

Chuck

Re your comment with what your expectations are (and these are my purely personal opinions and cannot not be justified at a purely factual level)

Highly appropriate for an experienced pilot flying a complex and relatively demanding power plant(s) in a larger aircraft

Quite unrealistic IMO for a new PPL who have just started flying their first aircraft with a variable pitch prop. My experience has been no matter how many times you tell them and do the practice exercises they will intially tend to revert to their experience to date which is flying simple fixed pitch props and when under pressure just mash the throttle in ( for the last miniute go around scenario). As they get more experience and practice, then they can dispense with setting the props to climb RPM (2500 PRM for most small aircraft and what I can see seems to the SOP for flying schools) as part of the prelanding check and bring the props levers up on very short final after the airspeed is low enough to put the props on the fine pitch stops.

Chuck Ellsworth

5th Dec 2009, 02:00

We are getting somewhere in this discussion as everyone expresses their opinions and their methods of conducting an approach......

...so lets fine tune it a bit more by taking the two ends of this spectrum and looking at the plusses and minuses for each end.

At the top end we have pilots who were taught to select full fine at a thousand feet. At the bottom end we have pilots who select full fine short final after power has been reduced to zero thrust or less.

The biggest concern seems to be having to do an instant rejection of the approach and go around, some here seem to believe that the prop pitch must be in full fine to accomplish a rejected approach and go around.

Why?

If the airspeed and aircraft attitude are in the required values and rate of descent for the conditions for the airplane being flown why would one need to ram on full power?

I used the PBY as an example because it's performance envelope is very low in fact much lower than any light single or twin airplane that I know of.

Therefore if the method I use for RPM and power selection works in a low performance airplane like the PBY it is only logical that light singles and twins will respond as well or better using the same procedures.

I am puzzled by the pre landing check that requires the props to be full fine before the landing gear is lowered. :confused:

If you are going to forget to perform an item on the pre landing check would it not be more important to have the gear down than the prop/s full fine?

Mind you if you touch down with the gear up that pretty well takes care of worrying about where the prop/s are for the go around. :E

pigboat

5th Dec 2009, 02:17

Chuck props fine on touchdown was our SOP at Northern Wings on the DC-3, C-46, PBY and Lockheed 10. I know of one company though, that used to advance the props on the DC-3 to climb RPM at the glide on an ILS front course. I seem to recall they used 20 inches of MP with that to maintain 105 kt.

Chuck Ellsworth

5th Dec 2009, 03:35

How's things Pig Boat?

Did you find a copy of that book I PMed you about? If not I can send you mine as I have finished reading it.

I would be very surprised if you did not use cruise RPM during the approach and move the the props to fine on touch down as it was the standard for operating those airplanes and worked just fine.

With the DC3 or the C117 you could just set a power setting once established on the glide slope and she would just drive right down to touch down with only one throttle movement needed..close them for touch down.....great birds and we were fortunate to have flown them.

Moose Murdock taught me how to fly both the DC3 and the PBY and he would have killed me if I brought the RPM up on approach unless there was a good reason to do so.

flyboy2

5th Dec 2009, 03:43

You're all correct it seems, BUT there are some geared piston-engines that " de-tune" the crankshaft counter-weights if the pilot shoves prop-levers forward when throttles are closed ( or power setting is low).
To avoid damage it was 'procedure' to leave prop RPM at cruise setting until landed!
For instance the Lycoming GTSIO or the Continental GTSIO; they are fitted to types such as Rockwell Commander 680, Cessna 421 etc.
Fortunately these engines have priced themselves out of the market these days!
Any comments?

privateer01

5th Dec 2009, 04:46

Ya can't detune the GSIO by increasing the RPM after the throttles are at idle.

I've run QueenAires and 421's to TBO.

I know where Chucks coming from. As I've about 3000 hrs with the R1820, R1830, and R2800 too.

Consider the early jets if you will vis a vis needing the power immediately.

Spool time on the early jets could be as long as 21 seconds.

So...really if you've managed your energy as was mentioned the 1 second it takes to push the props up isn't going to save the bacon.

I think its all part and parcel of the dumbing down of aviation.

Someone (possibly during upgrade from a single to a twin) forgot to push the props up while attempting a go around......and students have beeen taught to push them up early ever since.

Big Pistons Forever

5th Dec 2009, 05:18

I have lots of GTSIO 520 time and that is one engine you do not be want to be running the props at low MP unless the props are all ready on the fine pitch stops (ie the aircraft is below 100 kts). In fact run this engine just like a big radial and it will reward you with a trouble free life. The 421C I used to fly was sold with 1400 hrs on the engines and with no cylinders or turbochargers requiring removal in the entire period since the engines were remanufactured .

There seems to be two procedures which are being mixed in the discussion. my experience is the generally standard flight training SOP is props to the climb RPM setting on downwind (VFR) or prior to intercepting the approach course inbound (IFR). I have not seen any school that mandated full fine (ie max RPM) at these points. if anybody does than I think they are being rather silly since climb RPM is plenty to climb away from a baulked approach

Anyway my experience is the farther folks are away from actaully having to teach (note the present tense) low hour pilots the easier they find it to pontificate on how it should be done.

The bottom line is for the simple direct drive non turbo charged engines in trainers where to bring the props up is purely a style point as the engines will not be affected either way.

Chuck Ellsworth

5th Dec 2009, 16:45

I have made it very clear that I have not instructed at the flight training school level for decades and will freely admit that I am out of touch with the teaching methods that have evolved since I let my rating lapse.

However I have witnessed the abysmal level of skills and understanding of how to operate aircraft that are to be found coming out of these training facilities.

I have no desire to get into no win arguments with anyone here on the Pprune instructors forum Big Pistons Forever as that is part of the reason I no longer post in the Canadian forum.

It has been so long since I held a Canadian instructors rating that my Flight Instructor Guide has the learning factors referred to as " The laws of learning ". In the laws of learning there is a one called " The law of Primacy " ( Teach it right the first time. )

I do not buy into the dumb it down to make it easier for the student to learn a given exercise mindset, so they can get a licence and be able to then get enough experience to learn to do it a different way that will work better.

My personal opinion is to teach them how to operate an airplane in the safest and most efficient way that I personally have found works best that is within the operating limitations of the pilot operating handbook for the airplane being flown right from the start of their training for any exercise.

Sorry but teaching pilots to increase propeller RPM some minutes before landing is not something I agree with nor teach as I take the position that going down hill requires a reduction in power and increasing RPM is an action that that can be performed safely when and if needed.

So lets leave it at that BPF because I have no intention of dragging our differences over to this forum from the Canadian one. :ok:

SNS3Guppy

5th Dec 2009, 17:37

Much as I hate to agree with Chuck, I've been operating piston engines the same way for decades. I teach it that way, and operate the airplanes that way. Regardless of whether it's a large radial piston engine or a smaller flat horizontally opposed piston engine. I teach keeping the props back and operate airplanes the same way.

Someone earlier indicated that certain flight manuals require the RPM to be placed forward, and this is not the case. Don't confuse a checklist or a procedure with an aircraft limitation.

Don't confuse a recommendation or suggestion with a limitation, either.

In general with aircraft utilizing a constant speed propeller, I don't increase the propeller until the power is retarded far enough that I won't hear or see an RPM increase.

In certain conditions such as an approach in ice, I will increase RPM early, and I'll do it when conducting an approach to minimums in which a missed approach is a liklihood...or I'll start increasing RPM earlier.

So far as the argument of not taking one's hand off the throttle or power lever...it's a non-issue.

One may ride the power quadrant on the way down the approach with the hand behind the lever, rather than grasping the top of it, so long as one can push the power up or control it...does it really matter if one is grabbing the lever or the knob on top of the lever? With this in mind, in most multi engine equipment, one can easily push up mixture, propeller, and throttle easily from behind the lever.

Flying an airplane is not simply a rigid discipline with only one way to get the job done. More than one technique may legitimately be used, and this is one such area.

Personally, I don't like to hear a propeller wind up as one enters a traffic pattern or turns final approach. It's a sign of an inexperienced operator. It's unnecessary wear and operation of the equipment, and it takes an air cooled engine already operating at low power creates a situation where the slipstream tends to drive the propeller even more. Leave the prop back unless it's absolutely needed...then use what's needed.

Now some airplanes very nearly need the prop up for the extra drag, to prevent having to pull the power back during the approach. In these cases, pushing the prop up means that the necessary drag is created in order to allow the pilot to carry enough power during the approach.

Then on the other extreme, I flew for one operator who taught and used power to idle, props full forward steep overhead descents in the dark to blacked out runways using piston engines. Never an engine problem, every engine to TBO, faithfully. It worked in that aircraft, though I wouldn't have thought it would...and I wouldn't try it in most others. I found in that aircraft, reduced power descents were nearly always in order due to the operating environment, and these involved low power and high RPM descents with gear and flaps out...and it worked. Again, I wouldn't do that in most other piston airplanes, but in that particular airplane, it worked very well.

Chuck Ellsworth

5th Dec 2009, 17:52

Why do you hate to agree with me SNS3Guppy when we both have exactly the same opinions on how to best operate piston engine airplanes?

Is there something about my background that you feel is lacking or is it just something you can't quite figure out? :)

For whatever it is worth I find the mechanical side of airplanes to be far more rewarding and enjoyable than flying the things. ( Well there were a couple of jobs that were not very pleasant that I can recall. The salvage of a DC3 in the high Arctic in 24 hours of darkness was very cold work and an engine change we did in Jeddah was just as bad comfort wise with temps sometimes over 50 C. outside on the ramp in the sun...but I degress...)

DFC

5th Dec 2009, 20:01

I am puzzled by the pre landing check that requires the props to be full fine before the landing gear is lowered. http://images.ibsrv.net/ibsrv/res/src:www.pprune.org/get/images/smilies/confused.gif

I have read both debates in full and have not seen anyone say that.

I also have not seen anyone mention as you describe - "Full" fine.

You have gone off on a tangent to what was being discussed on the original thred and lost sight of the fact that there are very few students and low time PPLs with your experience.

Do you honestly expect me to give a nano second of thought to what a 10,000+ hour pilot would be capable of doing when deciding how to teach a 10 hour student?

Chuck, what would you expect a student to do when the recovery from a bounce is required on a short runway with obstacles at the end i.e. full power go-arround...........play with the levers that theya re not looking at while the aircraft gets ready to sit again even harder thanbefore?

------

Someone earlier indicated that certain flight manuals require the RPM to be placed forward, and this is not the case. Don't confuse a checklist or a procedure with an aircraft limitation.

The Arrow manual says select 2600, the Senneca says select 2500. There's two.

Please let me know how you select the 2600RPM (or any other RPM specified in the Flight Manual) setting when the prop is out of the governed range?

Milt

5th Dec 2009, 22:52

RPM or Pitch

Isn't it about time aviators handling props, having constant speed units, stopped calling the lever that sets a desired RPM a Pitch Control and isn't a setting of max RPM during a landing approach the worst position unless you want max drag.

The disadvantage is that at low airspeeds, during a landing approach, the prop will be at full fine pitch trying to reach max RPM. Then if you want some thrust in a hurry you won't get any until the RPM spins up to max with some overspeed before the CSU starts to coarsen the pitch. Not good.

Alternately with RPM set to around cruise RPM you can get a whole bunch of power and thrust much sooner which is what you want is it not? Of course if you want full power for a go round then you must know that the RPM setting has to go to Max in concert with the power lever. This operation then becomes optimumally close to the way FADEC works. .

Chuck Ellsworth

5th Dec 2009, 23:53

Naw Milt that line of thinking is just to logical and thus makes the subject to easy to understand.

You and I and a few others will have to get with the program to get any brownie points in today's flight training industry.

We have to quit thinking like this and get on board with the dumb'em down mindset driven by paranoia.

Somehow we just have not grasped the concept of teach e'm to set the airplane up so no matter how ham handed they are and how far behind the airplane they get they don't have to think about more than one task at a time. :sad:

Where do all these ideas like look at the far end of the runway during the landing come from?

Don't forget to wear your Hi Vis Vest and turn on those nav lights in bright sunlight....wouldn't want someone to run into you at the airport. :(

Big Pistons Forever

6th Dec 2009, 05:51

Dudley Henriques

6th Dec 2009, 13:06

Here is two scenarios that I recently witnessed (VFR)

Scenario 1: As Joe pilot (fairly high time) flies toward the airport the altitude is wondering up and down because the airplane is not in trim. He is way too high because he has not planned his descent, prelanding checks are late rushed and incomplete and the final approach airspeed varies from - 5 knots to + 15 knots of the ideal speed because of the wobbly flight path down final.... BUT he keps cruise RPM set untill short final and then smoothly brings the props up just before starting the flare

Scenario 2: As John pilot (fairly low time) flies towards the airport the altitude is held perfectly. He intiates a descent at the perfect spot so a seamless transition is made from cruise to descent to final where he nails the speed and flies a constant flight path to the runway....But as part of the prelanding check as he rolls onto final he brings the props up to the climb setting.

According to Chuck, Joe pilot is doing it right and John pilot is a victim of the "dumb it down mindset driven by paranoia". I guess I was all wrong when I though Joe was just a lazy, crappy pilot, while John was a guy who was doing a good job and flying the airplane the best he could every single minuite he was in the air.

I think the is legitimate value in discussing technique on an instructor forum but there is seldom right or wrong absolutes, rather legitimate differances that stem from personal preferences and experiences. I have found generalizations seldom add much value to posts and I particularly dislike when the failure to apply your prefered method seem to inevitably become a diatribe about how flying instructors do not know anything about teaching piloting.I must be missing something in this thread. :-)

First of all, Joe Pilot, sounds to me like he shouldn't be in the airplane in the first place, let alone in any position that requires setting his props :-)

Secondly, where you bring the props up on landing isn't written in stone by any reasonable definition unless your aircraft calls for it being done at a specific time in the approach for specific reasons. You bring them up where recommended by the POH, Dash1, Natops, or whatever other source official information is available for your SPECIFIC aircraft/engine combination.

There IS no magic bullet answer for this question that fits every propeller aircraft out here. It's THIS simple folks!
I can go into the dash 1 for a Mustang and find it recommended that the prop be brought up immediately after the gear goes down.
On the other hand, you can fly many aircraft, INCLUDING the Mustang, through the approach carrying some power with the prop in cruise, then bring it up crossing the fence.
Haven't flown any airliners, but BOTH these scenarios work just fine in an F8F-2 Bearcat with an R2800!
So what's all the fuss about folks?
The bottom line on this entire issue isn't who's a good instructor and who isn't. It's simply following procedures IF RECOMMENDED by a specific manufacturer, or bringing the prop(s) up in the approach when and where the approach calls for it.
Dudley Henriques

Chuck Ellsworth

6th Dec 2009, 14:06

Thank you Dudley for reinforcing what I have been saying all along.

I have explained that increasing prop RPM on final should be done if there is a viable reason to do so such as it being called for in the POH ( although I do not recall any that state the RPM must be increased on final. ) or icing or turbulence or any other viable reason.

Once again let me be clear and point out that the issue of when to increase prop RPM is at the discretion of the pilot and I personally do not increase prop RPM unless there is a viable reason to do so.

Teaching increasing prop RPM early in the approach so the student will not forget to increase RPM should he/she decide to go around is not what I consider to be the best method of training a student because they will tend to maintain that habit regardless of what they are flying.

*****************************************************

Now allow me to comment on why I believe Big Pistons Forever has this misguided idea that I hold all flight instructors in contempt.

First off I am a flight instructor and was one probably before Big Pistons Forever was born and I have stated before I believe that being a flight instructor is the highest calling a pilot can attain.

I believe Big Pistons Forever and I first got on the wrong side of each other several years ago on the Canadian forum during a discussion about flying tail wheel airplanes the subject of brakes came up and me or someone else commented that one can instruct on tail wheel airplanes without the instructor needing brakes on his/her side of the airplane.

Big Pistons Forever jumped on that statement and said it was to risky for the instructor not to have brakes on their side when teaching on a tail wheel airplane and he said he would never teach on such an airplane.

When I mentioned that in that case he would not have made it as an instructor had he started teaching when I did because some of the airplanes did not have brakes on the instructors side a very strong disagreement ensued...the rest is history.

So having explained why I think Big Pistons Forever started disagreeing with me I will let it go at that and I will from now on just ignore any negative comments he may make regarding my thoughts on teaching flying. :ok:

Terry_flyer

6th Dec 2009, 19:01

I have 2000hrs + on GTSIO-520 engines amongst other variants of continental engines and our current company SOP is to fly the approach / landing phase with the props at the last cruise position selected. We only push the props forward once power has been removed and the aircraft has touched down. This has been taught for many years with no reported engine problems due to this method. The GTSIO is a geared engine and as flyboy2 mentioned another reason to leave the props at cruise setting until landing is to avoid" de-tuning" the crankshaft counter-weights if the pilot shoves the prop-levers forward when throttles are closed.

The only time we are advised to push prop RPM forward on approach is if we encounter turbulence or airframe icing.

During initial training as you all know were taught that when advancing power you work right to left on the throttle quadrant and therefore if the props aren't fully fine during approach and a go-around is initiated, they shortly will be and therefore performance isn't compromised and I don’t believe that the time delay in doing so is that critical, if it is then the situation has already developed to far!!!

Also I find that if your flying an approach with a constant power as soon as the props are selected fully fine the student / pilot has to reset the power to maintain G/P and speed; therefore it actually destabilise the approach!! Granted if the props are selected fully fine at height then that would be a suitable SOP to use, but I would be reluctant to do this on short finals as a lot of people teach / do.

Also as pointed out above with the props fully fine - noise levels increase dramatically and the likely hood of noise complaints will be increased if flying in the traffic pattern.

Finally on such a maneuver as a flapless approach with the props at a low RPM they are less responsive if power is required quickly but it does allow for a lower throttle position due to a higher MP for the same throttle position therefore sometimes its easier to achieve the required VAT. Our company SOP is to fly the approach with the prop RPM at the last cruise or selected position.

I believe that what ever students are taught they will do and there is no right / wrong answer to this thread. Of course you should always do what the POH/FM as this will give you the over riding information on the subject and may well indicate more information pertinent to the reasons why such a technique should be used over another.

TF :ok:

pigboat

7th Dec 2009, 03:19

Thanks for the offer on the book Chuck, but I had one of my nieces go through Corner Brook the other day. Santa Claus is supposed to drop the book down my chimney on Xmas eve. ;)

DFC

7th Dec 2009, 10:09

Very interesting infor about

DC-3, C-46, PBY and Lockheed 10

as well as

GTSIO-520 engines

Hands up all the instructors who are teaching ab-initio students or low time PPL's on the above.

Very convenient for some to ignore what the POH for more common types say - as I have quoted previously.

Most of the posts seem to revolve arround a personal technique rather than thinking about what is going to fit the average student / PPL while complying with the POH / Flight Manual.

Chuck Ellsworth

7th Dec 2009, 13:16

Ahhhh we are back at that mantra about following the POH I see.

Have you read what has been said in this thread and missed the fact that I and most of the others who do not increase RPM until the power is at or below zero thrust just prior to the landing have said?

We point out that one should follow the POH recommendations and also use common sense with regards to when to increase RPM during an approach for landing.

Would you be kind enough to tell me if you think that a student learning to fly or a licensed pilot does not have the neurons to be able to understand a simple concept such as going down hill requires one to reduce power and if you want to go up hill you must increase power?

Are pilots dumber than people who drive cars and have no problem driving a standard shift car without an automatic transmission?

Chuck Ellsworth

7th Dec 2009, 13:25

Alister to answer your question lets ask one.

Should a pilot find them self twenty feet above the runway and fear they are approaching a stall and they have forgotten to move the prop pitch from cruise to climb or take off RPM and they applyl throttle to assist in flying out of a near stall situation what will happen?

Will the engine and prop produce enough power to help prevent a stall?

While we are in this position ( Twenty feet above the runway almost stalled ) what might be another concern if you quickly apply full power ?

Chuck Ellsworth

7th Dec 2009, 14:15

Alister you are reading things into what I have said that are not there.

No where have I said one should not have their hand on the throttle during the landing process, especially at the final segment of a landing which is the flare and the hold off just prior to touch down.

I can not think of a situation wherein one would be so far behind the airplane that full power is required to salvage a landing.

I can however think of many airplanes that would torque roll over on their back if full power is applied just prior to the stall.

To prevent or recover from a stall you first must reduce the angle of attack by moving the elevator control forward if the airplane is not in the inverted position.....the use of full power before reducing angle of attack can result in a torque roll that can kill you if it happens close to the ground.

Are you a student, PPL or a flight instructor?

Chuck Ellsworth

7th Dec 2009, 15:06

" So you idle the power at what height exactly? "

I generally close the throttle/s about a hundred feet above the landing surface in most airplanes I fly.

maxred

7th Dec 2009, 15:37

You would die in mine if you did that:eek::eek::=

Chuck Ellsworth

7th Dec 2009, 16:09

Alister the time required to move your hand from the throttle/s to the pitch control and back to the throttle/s has no bearing on your approach attitude as that is controlled with the other hand.

Now back to the subject of a stabilized approach, if you have been stabilized during the latter stages of the approach and reduce power to idle it only requires a slight nose down change to maintain the stabilized approach which is not a difficult task to accomplish.

I find it far easier to accurately flare from the approach attitude/ rate of descent to the level attitude so as to be in the level attitude with near zero rate of descent at one to two feet above the runway if the last hundred feet or so of the approach is power off if I am flying a tail wheel airplane and am doing a wheel landing which about 80 % of my landings are when flying a tail wheel airplane.

Flying a nose wheel airplane of course you will generally be flared to the level attitude higher that one or two feet above the runway.

By the way how many PPL students do you have that learn on an airplane with a constant speed prop that has a pitch control lever?

Big Pistons Forever

7th Dec 2009, 16:21

Katana DA20 has a CP prop and is widely used in ab intio training. My personal opinion is prop in cruise position untill flare, for students still working towards their PPL = bent airplanes....but you had better not listen to anything I say because I must be an incompetant instructor as demonstrated by my refusal to do tailwheel conversion without brakes on my side

Chuck Ellsworth

7th Dec 2009, 16:39

Incompetence was never suggested regarding our discussion on teaching in tail wheel airplanes B.P.F.

My comment to you was if you would not teach on tail wheel airplanes without brakes on the instructors side you would not have able to get a job as a flight instructor when we had to teach on such airplanes.

Therefore you would have had to wait until the training industry morphed into using only airplanes with brakes on both sides before you would have made it as a flight instructor.

As I recall you felt it was to dangerous to instruct on a tail wheel airplane without brakes for the instructor, I do not think it is and it went from there to here.

What is wrong with pointing out that?

Chuck Ellsworth

7th Dec 2009, 17:12

I should not have used the word " stabilized " in my description of lowering the nose to maintain a given airspeed when you reduce power to idle in at around one hundred feet above the ground...I should have said a controlled approach....

I agree that your hand should be on the throttle/s during the latter stages of the approach in case you need power to control rate of descent or to go around and that is what I do and teach.

*********************************************************
I have a problem with this lap top and I can't copy and paste as the right click function does not work, so I will just type your comments I wish to answer and put them in italics.

************************************************************ **

You said:

" A stable approach involves maintaining the same speed and angle until in ground effect. You can't achieve that unless you keep the power until ground effect. "

When training pilots for a type rating in the PBY I have them fly three minute circuits with the down wind leg at three hundred feet above the water.

At two hundred feet they must close the throttles and maintain the airspeed by lowering the nose to the attitude needed for the all up weight at the time.

The approach then becomes re-stabiized until the flare attitude is reached and the landing is completed...power off.

If they are unable to do that then the type rating training will not progress beyond that stage until they can consistently perform that method of approach and landing...in over thirty years of giving type ratings on the PBY I have never had a candidate not able to quickly learn that method.

Once they can smoothly and consistently perform power off approaches and landings from two hundred feet I let them use the power on approach and landings below two hundred feet if they want to.

mad_jock

7th Dec 2009, 20:02

Alister how many hours do you have on twins of any type?

I suspect very little.

I have 3000 hours and still am learning new things everyday.

Chuck isn't talking nonsense and isn't actually saying anything controversial its just so way outside your experience base you can't see it.

Chuck Ellsworth

7th Dec 2009, 23:14

Thanks Mad Jock, I can recall the early part of my career when I had very little experience and had formed some ideas of how airplanes should be flown based only on the very limited exposure I had to aircraft.

As time went by two things became clear, first I really did not know much and second I rebooted my thinking process and started to not only get actual flying experience from which to learn from but really started to listen to those who had experience.

I was very, very fortunate during my career in that I had some very experienced teachers who helped mold my thinking, from my early days in the crop dusting business to the training I got at Airbus Industries in Toulouse when I was in their employ.

Now I am at the point in my career where I am retired from commercial aviation I still have that need to keep teaching other pilots.

The internet is probably the very worst form of communication known to man or beast when it comes to interacting with others as there is no one on one interaction and the printed word is often taken in the wrong context.

When discussing the basics of flying with young instructors I try and keep things as basic as possible which is where I run into problems because quite often the basics are just to simple for some to grasp.

Simply put an airplane is an airplane and each type react to the controls and follow the same laws of aerodynamics and physics as the rest do.

The least understood of the different flying machines are pusher gyroplanes as they do have some rather different problems when it comes to stability when you get into the power push over realm.....they will kill you in a heartbeat if you go past a certain power setting and attitude/airspeed realm.

As to approaching and landing with zero power fixed wing airplanes are basically all the same from the tiger moth to the latest fly by wire wonders.

mad_jock

8th Dec 2009, 05:48

Your method is one way of doing it chuck.

Personally on one type of aircraft it would work with not many problems coming back from Vref plus 10 as you describe. The other type has the aerodynamics of a brick at flight idle and the props disking and barn door flaps.

I used to fly with a empire trained ex test pilot in fact the one that signed off one of the types. His method was exactly the same as yours.

Myself different technique depending on the aircraft type and also wx conditions. But then again low hours how many pilots get taught the difference between sliding it in using ground effect, driving it on and dumping it on.

DFC

8th Dec 2009, 10:06

Alister how many hours do you have on twins of any type?

I suspect very little.

I have 3000 hours and still am learning new things everyday.

Only 3000? :eek:

You sure are still learning!!! :}

When did we move from simply talking about props and start talking about the number of engines or experience of posters?

Chuck does a glide approach from a few hunderd feet. Changing from a powered approach to a glide approach is not stable if for no other reason that on order to arrive at the correct height above the threshold and the correct aiming point, these elements would have to be wrong up to the point where the throttles were closed..........i.e. the approach is unstable all the way down to the point where it is stabilised in the glide whereupon it remains stable for the remainder.

That is not how we teach the approach (in any aircraft).

This whole debate has revolved arround a personal procedure done in an unusual type in which no ab-initio training is completed. I have posted examples of two common training aircraft that require a fine pitch (high rpm) setting to be selected prior to the final approach.

The concern expressed by many here seems to be based on a misunderstanding about what was actually being spoken of in the original statement that started off this whole debate.

hugh flung_dung

8th Dec 2009, 11:33

Lots of interesting points have been made (and I'm very envious of anyone flying PBYs and DC3s) but I don't understand some of the concerns that have been expressed with regard to initially training people on "complex" aircraft.
I've always taught (and been taught) to leave the RPM at cruise until short final because the MAP is then relatively low and the props are on or near the fine pitch stop. One obvious exception to this would be when for some reason more MAP is required than is permitted for the current RPM setting, another would be if a specific type required a specific procedure that was different.
I can't imagine why any student would have difficulty with this, and I haven't seen anyone actually have a difficulty. However, it would certainly be easier to convert people if they were taught some from of short final check when doing their initial PPL training, but this seems to rarely be the case.

HFD

(PMs are welcomed if someone with reasonable aero, tailwheel and/or MEP experience is needed to fly/display/instruct an "interesting" aeroplane - but I won't hold my breath waiting for the replies;))

Chuck Ellsworth

8th Dec 2009, 13:09

My, my,my we sure get some different opinions about how to fly don;t we?

DFC I will respond to your post tonight as I am leaving for Vancouver in less than an hour to buy a Mong Sport that has a new engine I need for my Cub.

What prompts me to want to reply to your post DFC is your statement .

Quote:

This is not how we teach the approach. ( In any aircraft. )

For the airplane that I was referring to I do and for a very good reason.

You seem to be fixated on the word " stabilized " on the approach for what reason you are I have no idea but tonight I shall explain to you why I use the procedure I described in the PBY to train pilots on that airplane.

Maybe if you open your mind just a slight bit you will learn something new and expand your understanding of how to teach people to fly DFC.

The final measure of the value of a training program is the ability of the person being taught to fly at the end of the course......my record with students is excellent and the results are out there all over the world flying aircraft safely and with real skill, not like wind up monkeys blindly following skill sets limited by ignorance of how airplanes really fly. :)

Anyhow must go DFC, looking forward to us delving into this subject a little deeper and hopefully expanding your horizons.:ok:

Chuck Ellsworth

8th Dec 2009, 13:21

Just a short comment before I leave to catch the ferry to Vancouver.

The teaching I have done over the past decades is geared toward advanced flight training and skills upgrading for licensed pilots.

I was first introduced to this concept in 1959 during my initial training as a aerial application pilot.

The course was called " High command control " it taught us how to "fly " an aircraft and the word " stabilized " was never mentioned. :ok:

From that beginning I went on to develop a system of teaching aircraft handling that allows one to accurately and safely fly an airplane in complete control of where it is going.....consistently.

Flyingmac

9th Dec 2009, 10:35

When is an aircraft 'stabilised' on the approach? In my humble experience a hand flown aircraft is rarely stable to the point where you could take your hands off and it would fly itself down to the numbers. The vast majority of approaches require power/pitch corrections to a greater or lesser degree. As experience builds, these become instinctive and may not even be consciously carried out. Try stabilising a Pitts with a gusting crosswind and rollover off the trees on short final. As for the prop debate. In the Arrow it's 'prop set to go-around' when established on final. But that's just me.

Chuck Ellsworth

9th Dec 2009, 13:16

I see this thread still has life so I will make a few more comments.

First off when we get down to the point of micro managing an approach to the point that DFC brought this discussion to we are not even close to the real world of flying. Stabilizing an approach is fine especially in a heavy jet, however this forum is about teaching flying and that generally is not done in a heavy jet.

If a pilot is unable to cope with a simple action such as reducing power to idle at any stage of the approach and still arriving at your planned touch down point then I feel that type of pilot should stick to flight sim on the computer where he/she will not get hurt.

As to when and how to increase prop RPM during an approach I use a thought process that weighs the benefit versus the cost when deciding when to increase RPM.

If the engine is producing enough thrust to increase prop RPM high enough to create excessive noise and your intent is to continue descending for the landing you are using an RPM that is unnecessarily high for the task at hand...going down hill.

If you need to increase power that is in excess of the power needed for cruise flight you increase the prop RPM to the desired setting as you increase power...it is that simple.

If you are trying to keep it really simple for the student by not giving the student another action to perform ( increasing Prop RPM. ) because it may confuse the student how do you teach them to select carb heat cold and or change flap settings on a missed approach or a balked landing?

Jig Peter

9th Dec 2009, 14:28

When the RAF taught me to fly many, many years ago, on tailwheel pistons, (including the revered Harvard/T6) the Downwind Checks were Brakes Off, Undercarriage down below XXX knots (or, if in jocular vein, down & welded), Mixture Rich, Pitch Fine, Flaps as required - the BUMPFF check.
The reasoning was that approach and finals needed concentration, and if the checks were out of the way, one possible distraction was avoided. ALSO, my instructors reminded me, "From any approach, at any time, you may need to overshoot, for which you need Fine Pitch, Bloggs".
Crosswind checks before finals were "Three greens, Pitch Fine, Flaps Full (or as reqd) Power as required".
That way you got the in-cockpit work done & dusted early enough to be able to concentrate on look-out, the approach, and the landing itself. Incidentally, when I was on fast, big 4-jets (painted white, of course !), my captain had many years' experience on the Catalina (PBY?) and used basically the same checks, topping off the Plotter's call-outs: he sometimes also added a check that we would NOT be landing on water, so the wheels were needed ...
Hope this is sort-of relevant I know that "That was then and this is now"
:8

Big Pistons Forever

11th Dec 2009, 04:33

This thread started with a question on what RPM should the prop control be selected to provide on landing.
I am now confused because it seems most posters are talking past each other.

So are we talking about training for the PPL or best practices for the professional pilot ?

I firmly believe that flight instruction must proceed from the simple to the complex. This applies just as much to teaching procedures as it does to teaching the hands and feet. It is not realistic to teach everything on the first lesson for every exercise. For that reason at the PPL level I have the students set climb RPM as part of the prelanding checks and leave it there. Anyone who has taught the PPL knows that on the first landing lessons the student is fully occcupied on keping the aircaft on the correct flight path and aligned with the runway centerline. To say that the average students has the spare capacity to reliably attend to the prop control in the final stages of the landing approach, is IMO living in a fantasy world. However for advanced instruction one should insist on a higher standard. For advanced instruction (CPL and IR) I start with the climb RPM set and as per the above but want to see the prop control smoothly moved up the full fine position when the prop is on the fine pitch stops (ie so that no actual increase in RPM occurs). When the student is reliably performing that action then when the prelanding check is performed the prop position is noted and a discison made as to whether to leave it in cruise or raise it to a higher value in view of the current circumstances affecting the flight. In other words where the prop control gets set is not part of some one size fits all dictat but rather a result of logical and informed pilot decsion making.

Pugilistic Animus

11th Dec 2009, 20:06

Anyone who has taught the PPL knows that on the first landing lessons the student is fully occcupied on keping the aircaft on the correct flight path and aligned with the runway centerline.

not during mine, I was trying to keep my instructor on centerline:E

Chuck Ellsworth

11th Dec 2009, 20:54

O.K. I have read the first post I made here and it seems I was not specific with regard to the level of experience of the pilot.

So lets examine it from the first lessons being given to a PPL student.

If the POH does not specify at what power setting one should select a higher RPM before landing how do you determine when to increase RPM with regard to the power setting at the time you select the higher RPM?

For instance if you are using a power setting that will result in the RPM surging due to the power being high enough to cause surging of the governor is that O.K.?

By the way I was not referring to initial PPL training when I started this conversation I was directing it at licensed pilots either being newly trained on constant speed propellers or pilots flying the things on a regular basis. :)

Big Pistons Forever

11th Dec 2009, 21:11

not during mine, I was trying to keep my instructor on centerline:E

I had a few students that started out with major attitude.....it did not last long....they either realized I was serious when I would not put up with any substandard performance so they ended up working too hard to be cocky.....or they found another instructor:E

Pugilistic Animus

12th Dec 2009, 18:22

I did know much more aerodynamics than he:E

however if the fella who wrote this wanted to review some things with me, I would definitely keep my trap shut:oh:

I feel it's always best to make no assumptions about how much the student (http://www.pprune.org/#) understands, and therefore start at the basics. This will nearly always entail some review for the student, but this is fine.

except I've always had a bone to pick with him on LOP vs ROP ops on the IO330,...NO,NO just kidding, really:\

Further, I remember when Chris told me "dude, you are worse than the examiner",...I loved flying with that guy, one of the best instructors--a real stick and rudder type:ok:

PA

FlyingOfficerKite

14th Dec 2009, 19:43

It all seems to be about 'safety' and standardised SOPs insofar as training for the CPL/IR is concerned - aimed at making sure you don't forget as a number (?) of trainees would probably do if required to go around in those circumstances.

The technique I was taught was to leave the props in the 'approach' setting (typically 2400 rpm initally depending on aircraft type) and then at 500 feet agl carry out the Reds/Blues/Greens finals check.

I have never noticed an increase in prop RPM at that stage of the approach with the normal (say 13" manifold) power settings. Never noticed the speed of the props to be fair - too intent on flying the approach.

This seems to combine the 'safety' issue and the 'care of the propellor' considerations without any trauma.

KR

FOK

DFC

16th Dec 2009, 09:00

and then at 500 feet agl carry out the Reds/Blues/Greens finals check.

To take this back to the original reason for the question - How often when you do this "check" at 500ft do you find that the actions have not yet been carried out?

If what you intended to say is that you carry out the Reds/Blues/Greens actions (flow) at 500ft, when do you do the check that the actions have been completed or is that check not done?

-----

Chuck,

If the POH does not specify at what power setting one should select a higher RPM before landing how do you determine when to increase RPM with regard to the power setting at the time you select the higher RPM?

For instance if you are using a power setting that will result in the RPM surging due to the power being high enough to cause surging of the governor is that O.K.?

Taking the Piper Arrow as an example. This operator's handbook says set 2600 RPM (100 below red line).

If the propeller is out of the governed range then how can one set 2600?

I do not think that anyone approves of shoving the prop lever to the max while at cruise power and resulting in the Max RPM being exceeded while the govenor plays catch-up.

But, smoothly and carefully moving the RPM from 2100 (cruise setting) to 2600 (fine setting) as per the POH can not be done on short final.

S-Works

16th Dec 2009, 11:21

My props go full forward to 1900rpm at about 3000ft.

Always Moving

16th Dec 2009, 12:13

I put them forward after dumping the gear and reducing power FAF or downwind and if you do it slowly you do not hear any noise (and I would think the RPM are out of range already) and hardly ever, a power change is needed (I am talking cabin class twins)

Somebody mention FADEC's I guess they did not listen to the prop going from high pitch to low pitch to high pitch again! (and the first time giving you a heart attack too!LOL the RPM-power curve looks like a drag curve)

I do not like hearing people jamming the RPM indeed CHUCK!

maxred

16th Dec 2009, 12:31

Looking over BPF post, looks like he is stating that on the downwind, 1000' drop gear, some flap, turn base, mine has Continental IO-470-N, set MP at 15, turn final at say 500', reds/blues greens check, with the prop set at climb - I climb out at 25 squared, therefore should look like 13.5/25. Assuming speed over the hedge is ok, 85kts, then leave the prop alone - i.e it should sort itself out. Have I missed something, or is this a recognised (taught) process?

S-Works

16th Dec 2009, 12:51

I think you have to realise that it has to be horses for courses rather than a dogmatic only 1 way will do approach.

At work, I set flight idle around 3000ft, props full forward to 1900rpm. Maintain flight idle to circuit height then set 18% torque which give me 100kts in the circuit. Turn final, back to flight idle then fly beta which I hold until touch down before full ground beta. You can't put beta in without the props being forward or you will bend the control rods on the engines.

On my Cessna I put the prop forward when I have taken off the power on final as at idle or very low RPM it is outside the governing range so makes no difference but it is one less job to do in the event of a go around.

Chuck Ellsworth

16th Dec 2009, 14:33

DFC somehow you and I are on the wrong page with this conversation so allow me to try and explain what my position is on this subject.

First off if the POH has a requirement for increasing prop RPM on a given airplane then one should follow the procedure as outlined.

Where I stand on this subject is I often see pilots select climb or even worse full RPM when doing their initial landing checks such as downwind for instance resulting in a surge of RPM due to the power setting being high enough to result in the prop changing to fine pitch. Not only is this annoying noise wise it results in unneeded wear on the engine parts.

It has been thirty nine years since I flew a Piper Arrow and can not remember what was in the POH.

Does the POH for the Piper Arrow state at what point in the approach the increase in RPM be performed?

And last but most puzzling to me is why do you think you can't select a higher RPM on short final?

I never had any problem doing that.

SNS3Guppy

16th Dec 2009, 19:06

Turn final, back to flight idle then fly beta which I hold until touch down before full ground beta. You can't put beta in without the props being forward or you will bend the control rods on the engines.

To which powerplants do you refer?

You appear to refer to a turbopropeller motor. What turboprop engine can't be reversed or put in beta with the speed lever or condition lever not forward?

FlyingOfficerKite

16th Dec 2009, 19:26

DFC

In answer to your query - never!

That's one reason I have never landed 'gear up' and the one reason I (hopefully) never will.

KR

FOK

S-Works

16th Dec 2009, 20:56

To which powerplants do you refer?

You appear to refer to a turbopropeller motor. What turboprop engine can't be reversed or put in beta with the speed lever or condition lever not forward?

Walter M601 D-2 Turboprop engines as installed in the DO28 G92 and SMG92.

DFC

17th Dec 2009, 09:58

I asked;

How often when you do this "check" at 500ft do you find that the actions have not yet been carried out?

and FlyingOfficerKite said;

In answer to your query - never!

Which leads me to ask, where then do you do the action of moving the prop to fine so that at 500ft "check" you always find it to be in that position?

-----------

Chuck,

And last but most puzzling to me is why do you think you can't select a higher RPM on short final?

I never had any problem doing that.

If the prop is out of the governed range it is impossible to set a specific RPM unless perhaps one has a gated prop lever.

The whole idea about instructing and examining is not to sit there and think "I never had any problem doing that." because it is about the student / candidate and not about you.

Many of your examples seem to me to show that you like showing your students what you can do with the aircraft rather than teaching them what they need to do with the aircraft. Are you an instructor or a demo pilot?

The fact that you never had a problem with something is irrelevant when it comes to teaching the student / PPL.

Centaurus

17th Dec 2009, 11:21

Gentlemen, I totally agree with you. PUF check was the one I was taught (which amounts to the same thing ; I'm sure there're others):

Ah Yes! The good old Aussie flying school "PUF" check. Except one school goes beyond that and does "PPUFFF" check on short final which means and don't laugh but this is exactly what the poor bloody students are taught by their "professional" instructors.
Pitch - Power Poles - Undercarriage - Flaps - Furry Friends" -and that is for a fixed pitch prop and fixed landing gear type like the Cessna 150...:ugh:

Mach E Avelli

17th Dec 2009, 22:27

Seems we can summarise all this into:

1. Basic light aircraft, normally aspirated engine with CSU - doesn't matter much when you select fine pitch 'cos it won't damage anything - but select it early enough not to get all crossed-up on short finals and so as not to forget it in the event of a go-around. Because usually those flying this type of machine are in the learning stages, so we don't need to complicate matters.
2. More advanced twins with geared, turbo or supercharged engines and larger radials - keep the M.A.P. up with cruise RPM, adding drag progressively with gear and flaps and leave the props alone until in the flare - in the event of a missed approach; RPM up, power up - GENTLY. Pilots entrusted to this level of aeroplane should be able to cope with the additional complexity of pushing a couple of levers up at the flare or making a smooth transition to a go-around.
3. Turboprops - strictly in accordance with the POH or AFM - which usually requires condition levers to 100% sometime on the approach. Pilots flying at this level will probably be bound by a checklist and company SOP that says so.
4. If it is a rental aeroplane - whatever the owner/operator requires. It's their engine overhaul cost.