CASA Flight Instructor's Manual

[training wheels]

I was skimming through the pages of the CASA Flight Instructor's Manual (http://www.casa.gov.au/wcmswr/_assets/main/aoc/training/guides/fim.pdf) when I came across this section on Descending on page 22. The instructions show the method for entering a descent and levelling off. Does anyone else see a problem with figure 7.1?

http://i27.tinypic.com/o7w0lw.jpg

I've always been taught the method of entering a descent to be "Power, Attitude (airspeed), Trim". And the levelling off to be the same, Power Attitude Trim. It seems like the manual has got it mixed up with APT at top of descent, as well as when levelling off.

Is the CASA Flight Instructor Manual showing a new way of doing it, or have they made an error?

[OZBUSDRIVER]

Hmmm, bit of a typo. Even reading the relevent paragraphs does not explain why....a bit vague...blue book was better:ok:

[training wheels]

Hmmm, bit of a typo.

Even if it was a typo and it wasn't picked up by the proof readers, I still see this as a major fundamental error that should be corrected. This is a manual for Flight Instructors to use when preparing briefs for their students so it should be of high standard, especially coming from the regulator who set the standards!

And so much for CASA wanting to raise the standards of flight instruction when they themselves can't get it right?

I'm happy to accept that I'm wrong and that the CASA manual is right. But if the manual is wrong, then it should be corrected.

[Tee Emm]

...blue book was betterhttp://images.ibsrv.net/ibsrv/res/src:www.pprune.org/get/images/smilies/thumbs.gif

Agree. The blue book CASA Flight Instructor's Manual DA 2342 was a model of concise writing and far superior to the current publication. Especially the "Aim" which was brief and to the point. The waffle and duff gen contained in the new Instructors Manual was the result of too many committees having their say. In the example given in this thread the subject is descending. Yet the word "Look-out" precedes each action of entering and ending.
To carry that to its logical conclusion the word "Look-out" should be at the beginning and end of every sequence in the whole publication. And that is superfluous.

[Mach E Avelli]

Surely, whenever the engine is turning and burning, it is Power controls speed , Pitch controls flight path and this applies whether going up, level or down? Therefore the sequence is always Power-Attitude-Trim, from takeoff to final approach. The exception being when there is no Power (as in a true glide approach, best left to the space shuttle but still a necessary evil to be taught 'just in case') when Pitch is King. The whole issue of flight path control on descent and approach seems to have become some form of black art when it could be made so simple if reduced to the above terms.
I suspect that this manual will continue to confuse future generations of junior instructors and trainee pilots as did the old. Or maybe I have been doing it wrong all this time and not realising it.....

[Arm out the window]

Depends on the speed you're at, and the speed you want to maintain in the descent.

If you're cruising at 120 kt, for example, and want to descend at the same speed, you would go:
Attitude, power and balance all together, then trim.

If you wanted to descend at a slower speed for some reason, you'd reduce power, balance and maintain attitude, then as speed approached what you wanted, set descent attitude and re-trim.

This can be a bit of a chicken and egg argument which, depending on where you learnt to fly, can have a different focus.

Power controls speed , Pitch controls flight path

Not knocking how people do things, but for example, if you're in a climb with max power set, it's attitude for airspeed, isn't it?
There are lots of times where you might use different techniques to achieve the aim effectively, and decent supporting arguments for each.

[Aerodynamisist]

I learnt and later taught, PAST - power, attitude, speed, trim for all phases except levelling off from a climb where one would use ASPT - attitude speed power trim (speed builds up then reduce power then trim) the objective of doing it this way is that you only have to set your attitude once and trim once, at top of descent if you first reduce power maintaining your S&L trim the attitude will pitch nose down slightly very little adjustment needs to be made to the trim, same goes for entering a climb from S&L apply power nose pitches up set your climb attitude and adjust for airspeed and trim.

Not sure why casa has done it this way, if you set attitude first - then reduce/increase power the attitude will change so you then need to adjust the attitude again.

It could have been worse though, they could have let a bunch of military instructors loose then it would be full of energy this and energy that.

[The Green Goblin]

CASA is actually correct.

Yes when learning to fly you go PAT but in the real world of aviation you point the nose down, speed up as fast as you can and reduce power as required to keep within specified limits. If you're in a piston you will inch back the power slowly on decent as you approach the circuit to avoid shock cooling. In a turbine you keep it barbers pole minus 5-15 all the way down :ok:

[OZBUSDRIVER]

GreenGoblin, maybe so. As long as this is not heading for learning for a job as opposed to learning to fly type arguments.

Crawl, walk, run...any other way leads to disabilities..in life, experience, as well as job.

I hope it IS a typo.

[PA39]

HO Hum.....if you reduce the Power first the Attitude follows naturally and then Trim. In my book its always been PAT on ToD and APT on ToC.

Reference to the CASA Manual " explain the forces acting in a GLIDE....."

[grip-pipe]

Well the manual is correct. It is based on the simple formula that should be burned into the brain of any driver - Attitude + Power = Performance. Ergo, attitude, power then trim. May happen simultaneously, maybe a lag, either way it is the method to successfully get across the message that if you want to be a competent driver, visual or IFR, then you have to learn to fly an attitude. Green Goblin is correct, set the attitude and then reduce the power and trim, fast if it is a turbine, fast if it is a piston, what is the point on not letting gravity do the work for you.

What is desired is the ability to set a precise attitude (pitch either on the AI or reference to the horizon) then making adjustments to power to control either ROC or ROD. The trick therefore is A+P=P is that it is not understood clearly by many especially what pitch and power settings produce what performance, most do not have a clue especially for lighties even though close observation and a read of the AFM would reveal all and wonder why they have problems adjusting to big aircraft. Once you master this simple process the rest is easy.

[training wheels]

I take your point gripe-pipe, but what about in the circuit, when you're on base and about to set yourself up for a descent? If you use Attitude, Power and then Trim, then it would take much longer to get the speed back in to the white arc to extend flaps, and set yourself up for a stabilised approach on final.

Remember, the flight instructor's manual is aimed at ab-inito student pilots with possibly less than 10 hours TT by the time they do "climbing and descending". I've been taught Power-Attitude-Trim for descents, and it seems like a number of instructors or ex-instructors on this thread have been teaching it this way as well.

[The Green Goblin]

I take your point gripe-pipe, but what about in the circuit, when you're on base and about to set yourself up for a descent?

You should already be in one!

fly a profile from TOD getting dirty on the way down using power to maintain your sink rate.

[Jabawocky]

I did this in another thread.....so here goes....not my brains, just copied some others!

Here Endith the Lesson!

Pelican's Perch #54:<br>Pitch, Power, and Pink Elephants (http://www.avweb.com/news/pelican/182148-1.html)

J:ok:

I know you are all busy reading and thanking Jaba for this link, but pay attention to this paragraph!
Lots of airplanes now have autopilots that can make the ILS approach look disgustingly easy, and autothrottles to control the thrust. Guess what the autothrottle computers react to? Why, errors in SPEED, of course. If the speed drops a bit below the selected speed, the autothrottles move forward, and if too fast, the autothrottles move back. Pretty simple, to me. As an entirely separate matter, if the airplane goes a hair above the glide slope, the first action by the autopilot is to pitch down to return to that path. If that changes the speed, fine, then the autothrottles correct for that as a secondary reaction, but that's often too quick to observe. That all seems to be proper design to me, and it mirrors EXACTLY what a human pilot would do, intuitively

[training wheels]

You should already be in one!

Just repeating what I said before; I'm referring to 10 hour ab-initio student pilots here doing circuit training. Circuit height is top of descent! :p

[PA39]

Your correct training wheels, and the phrase is Power + Attitude = Performance. keep doin' what your doin' mate.

[grip-pipe]

Training wheels - There should be no difference in the circuit either. The variations or confusion arises from the form of the circuit taught. It is the general practice in civil flight training to fly a square circuit, the military teach a different method of using a constant attitude and constant turn from upwind, levelling off downwind, then another constant attitude constant turn from late downwind to final. Therefore with the latter method you set the attitude (bank angle and pitch), adjust the power to control rate of descent and trim. Small changes in pitch will control speed and allow for flap extension which will re-pitch the aircraft nose down, balloon from the extra lift is controlled by maintaining the pitch attitude, again then a small attitude change, adjust the power for the extra drag and trim. The argument about square v round circuit is as ageless as flying itself and there will be those who claim one is better than the other. Sloppy speed control in the circuit is the problem, there should be a series of speed gates and visual clues used to arrive at the base turn point at the correct height and speed, so minimal changes in pitch and power are required during the base turn to allow for flap and to ensure the speed is kept within a precise but controllable range. Again sloppy speed control is fixed by flying a precise attitude and power setting on downwind to arrive at the base entry point. All in all you are flying the aircraft not letting it fly you around. Cheers.

[Johnny_56]

What about the section on stalling? Just above the diagram it says - lift increases until the critical angle is exceeded.

I thought the coefficient of lift increased but lift stayed the same due to decreasing airspeed.

[Tee Emm]

If you're in a piston you will inch back the power slowly on decent as you approach the circuit to avoid shock cooling

Suggest you read John Deakin's articles (Google it). Years ago he wrote a brilliant and factual series of articles on piston engine handling for AVWEB internet website. These included mixture use. He also proved from measured tests that so called "shock cooling" was a long standing aviation myth. Gradual reduction of throttle every few minutes does nothing to prevent cylinder head cracking. It is harsh throttle slam opening and closing that causes engine damage.

If shock cooling was a real problem then closed throttle glide approaches as in practice forced landings would be banned. Flying through rain will cool cylinders very quickly; after all, the cold water covers the front cylinders by direct impact and CHT's often indicate low when flying through ice and rain - but you don't hear too much of cylinders cracking after flight through rain showers or even heavy rain. Most instances of cylinder head cracking can be traced to second hand items refurbished several times. This info comes directly from Lycoming.

[The Green Goblin]

If shock cooling was a real problem then closed throttle glide approaches as in practice forced landings would be banned. Flying through rain will cool cylinders very quickly; after all, the cold water covers the front cylinders by direct impact and CHT's often indicate low when flying through ice and rain - but you don't hear too much of cylinders cracking after flight through rain showers or even heavy rain. Most instances of cylinder head cracking can be traced to second hand items refurbished several times. This info comes directly from Lycoming.

Fly a bigger piston engine such as a Continental IO-520 and see what happens if you don't nurse it.

Oh and If you fly something like a TSIO-540 you are required to inch it back, but you fellas in the UK don't get the same exposure to piston aircraft operationally as there is little GA to speak of.