Stick or throttle?

[Bronx]

A lot of waters gone under the bridge since I last flew a flying machine where you dont' stop before you land but a conversation with a student airplane pilot got me thinking.
On approach, do you guys use stick or throttle to control your airspeed?
I hear some folk say 'Stick for airspeed, throttle to control RoD' but that seems the wrong way round to me.
I can see how it can work if you're hot and high on the approach. If you're high who cares, but how does it work when you're close to the ground and the numbers are coming up big in your screen?
If you find yourself slow and low, do you point your nose at the ground?
If you point your nose at the ground ain't you gonna lose lift before you gain speed?
Which way are students taught? Seems kinda risky to teach them to lower the nose if they're slow and low.

I say use your throttle for airspeed and use your stick to get the flightpath you want.

Am I wrong? :confused:


Do they teach different methods in different countries?

[Flyin'Dutch']

This very subject was discussed in an article by John Farley in this month's edition of Flyer.

For the reasons you mention he advocates the use of throttle for speed and stick for ROD as you do.

Indeed if you lose speed very low down and stuff the nose at that point you can be in trouble and nobody can argue with that.

However when you fly gliders you have no option but to get it right (other than being able to close the airbrakes)

I think that most experienced folks do a combination of both (which is really what needs to happen) but for teaching purposes the mantra attitude = stick = speed seems to work OK as does engine = ROC/D.

Interestingly enough most folks fly ILSs using the stick = ROD and throttle = speed method.

FD

[Monocock]

The method that feels more natural is stick for ROD and throttle for speed. This however is not the correct way and certainly not the easiest way.

If in fact you approach it the OTHER way you'll find your approaches FAR more accurate and speed control very easy indeed.

There is a definite delay in ROD control when using the power for this but once this is compensated for, thje numbers can be touched down on really quite easily.

I think the reason the ILS approach is easier with the principle reversed is that there is no visual reference on an approach in cloud.

[Whirlybird]

This has been discussed several times on here. The conclusion seems to be that there is no "correct" way, but that stick for airspeed, throttle for ROD seems to be most commonly taught. However, as stated above, if you do that close to the ground you'll be in trouble. And again as stated above, most experienced pilots use a combination of the two...I know I do.

[Miserlou]

I'd like to point out that a burst of power at the point of stall may well CAUSE the aircraft to stall. Increasing the down force on the tail with very limited increased lift from propwash and none at all yet from airspeed is a recipe for disaster. You want to be reducing the back pressure (stick moving forward) first.

Whereas I would agree that it is almost indistinguishable which action one is doing to correct what I'd like to explain further the ILS situation.

Flying an ILS I have the aircraft trimmed to the correct speed and then leave it there. There maybe tiny corrections to maintain the glide path but these are to small to trim out. As soon as there is any trend in the pressure required to maintain the glidepath then it's time for a power change. Due to the changes in windspeed with altitude you will always need to change the power setting on the way down but you can arrive with the aircraft still trimmed correctly at the right speed (and thats where good landings come from).

However if you are performing an autopilot approach (without auto-throttle) then you will be controlling the speed with the power alone.

It's bit of a chicken and egg thing but it is of utmost importance that one knows that speed control is the stick.

[Bronx]

Whirlybird

It might have been discussed several times on here but I ain't seen it and I'd value folks opinions based on their experience.
You say experienced pilots like you use a combination of the two. Sounds kinda sloppy flying to me. Do you kinda fudge it all the way down the approach? Or you change methods half way down?
How do students know when it;s too low to the ground? If it gets tricky must they forget the method they've been taught and do what feels good using their initiative but no experience?
:confused:

[TonyR]

It has always been a combination of the two, I see the point for teaching students, it is simple to teach stick for speed and throttle for ROD.

But if you take level flight, throttle = speed

And I was taught on my first lesson that if you push forward "cows get bigger"

Most of us without thinking, reduce power to a setting that when we push forward to a 500 fpm ROD, we maintain a certin speed.

If we were to hold 500 fpm ROD and increase power then we would speed up, and if we reduce power and hold 500 fpm ROD we would slow down (unless we had a best glide ROD of less than 500 fpm).

I think we all actually use throttle for speed and stick for ROD but it is easier to trim for 80 knots than to trim for 500 fpm ROD.

Confused??

Tony

[benhurr]

If we are talking SEP then.

If high, but at approach speed you need to reduce power AND lower the nose.

If low - bang in the power and raise the nose - this makes the cows become smaller which is a good thing.

If you are low and slow then power is the only thing which can save you.

Flying an ILS? Totally different technique - set power for configuration and desired airspeed, if the configuration changes then the power required also changes but to maintain the glideslope then stick does it.

There is a big big difference between precision approaches and visual approaches so clearly there is a big difference in the skills involved. If the cows look too big then apply power - if you use stick then you might well find yourself in the pooh.

If ROD is too great in a SEP, low momentum machine, then power is always the answer - certainly on final approach. You can always go around and try again. Try recovering with stick and I think your flying might be finished.

Ask an instructor for the best response when low and slow - pitch up or full power?

[High Wing Drifter]

Could this not be one of those things where there is no firm rule across types. My 'vast' experience encapsulating nothing more than PA28, AA5 and C152 seems to tell me that the official technique does work very well on a C152 but not so well on an AA5 which loves to pick up speed and doesn't like to loose it (in comparison!); where the combined method seems to be more appropriate, especially on short final.

[BEagle]

The teaching of 'point and power' to fly the final approach has made it much simpler for students to learn accurate speed and glidepath control, resulting in them soloing at least an hour earlier on average than using the old technique.

Edited to restore the point I made earlier, which the moderator decided to delete :mad: :

Search on the Flying Instructors' Forum and you will discover that this topic has been covered extensively in the past.

[TonyR]

I remember a great article in "Flying" by R Collins on "Energy management", just can't seem to put my hand on it, but it was not that long ago.

Thats really what we are doing, "Dealing with energy" on the approach.

Tony

[Heliport]

BEagle

Please can you explain 'point and power'?

In what way is it better than stick for speed and throttle for height?

Is/was there any difference between the technique taught by the military and GA?

Which technique is taught by the new tri-service basic training people?

Thanks.

Heliport
Moderator

[DRJAD]

For me, much as Flyin' Dutch said at the outset, it's a combination method for a visual approach. I don't analyze it too much, I'm not an instructor, but I would guess that the majority of the time it's ROD with elevator, and speed with throttle.

On the ILS its ROD with elevator and speed with throttle - though again, I think that for me too much analysis would get in the way. I would rather find an instinctive method which gets me in a suitable place, at a suitable attitude, and at the right speeds.

[Final 3 Greens]

TonyR

I agree.

[Send Clowns]

It's more a philosophical difference than a practical difference. I always teach (as per CFS-trained pilots who taught me and my FI(R) instructor here) control rate of descent with power, speed with attitude. One reason I do so is prevent students trying to stretch the approach, as a stall is about the most dangerous situation at this point. Low and slow is not good, but if you are so low that power is taking you into danger then I suggest a go-around to an inexperienced pilot, an experienced person would instinctively use both at once.

There lies the core of the issue. If I am high, I will reduce power. I know this will tend to reduce my speed, so I lower the nose at the same time to retain approach speed. If I am fast, I will raise the nose. I know this will take me high, so I reduce the power. However if I am low I do not think "raise nose" I think "increase power", so I will not try to stretch an approach and bring the speed low.

In effect height is always controlled primarily using power, and speed primarily with attitude. Giving trial lessons I always control the throttle, the student the control column, and this point becomes obvious. Maybe it helps having flown helicopters!

DrJad

Try the other way around on the ILS. You may well find they suddenly become a lot easier, as this is where the difference is most apparent to me. As described above set the power for the overal ROD, attitude for speed. Small adjustments in glideslope with elevators but if the ROD is wrong then reset the power.

BEagle

I would suggest that on a typical light single point and power is a lot harder to learn than the classic/military technique (I realise that on a slippery jet it can be easier). What do you mean by point? Because of the different attitudes flown depending on flap state, speed of approach (airspeed change for a short-field landing, groundspeed change in different winds) and aircraft type. How do you define when the aircraft is pointed at the threshold? That is without the increased danger that a student may try to stretch the approach and not put on the power if low. For this last reason alone I would feel the need to delay sending students solo until they had proved themselves more thoroughly, just to make sure they don\'t kill themselves.

[BEagle]

Generally, in any descent the control column controls IAS and the throttle controls the rate of descent. Fine. But when you are on the final approach, a 3rd factor in addition to IAS and RoD is introduced, the touchdown point.

Once the a/c has rolled out of the final turn and has been properly configured for landing, it will ideally fly a fixed angle descent path to a fixed point on the runway.

To assess any error, a deviation from the required value must be quantified and assessed. Using the old method, the student - in addition to controlling the ac - had to assess whether or not the was on the correct descent path, or rather where the descent path he was on at the time would intersect the ground. This is a difficult skill for the student to learn as the has no 'angle-meter' to look at to provide his angular error information and must do so visually, whilst at the same time adjusting speed with the control column. This then gives him a different approach aspect to assess whenever he changes the power setting.......

With 'point-and-power', the ac is rolled out of the final turn, configured for landing and adjusted to the correct approach speed with the control column. Then the pilot literally aims a fixed spot on the windscreen at a fixed spot on the ground and holds it there with the control column. Zero optical spin. If he did nothing else he would arrive at that spot on the runway.....but at what IAS? Now comes the 'power' bit. Because he does have a meter with which to assess the IAS error - the ASI! Point at the runway touchdown point and assess IAS. If IAS low, add power KEEPING THE TOUCHDOWN POINT STEADY in the windscreen; as the correct IAS is achieved, wriggle off a little power to peg the IAS. Follow the activity cycle 'Touchdown point - speed - touchdown point - speed'. Because only one value (IAS) is changing with the other (touchdown point) held steady, students naturally find this much easier to learn.

To sum up:

Roll out of final turn.
Wings level
Land flap
Adjust to approach speed with control column and trim
Now aim at touchdown point
Keep touchdown point steady with control column, IAS controlled with small, frequent power adjustments
Just before impact with ground, close throttle smoothly and fully.
Now aim at far end of runway and align a/c with runway direction using rudder, keeping wings level.
Clench buttocks
Land

Point-and-power is dead easy and I've used it in Cherokee, Chipmunk, Bulldog, T67, Zlin, JP, Gnat, Hunter, Vulcan, Hawk, VC10..... (F4 and Buccaneer had AoA to worry about as well!).

Get a FI who understands the technique to teach it to you and you'll find it vastly easier than the 'old' method!



(Any references to the masculine gender contained herein are equally applicable to the feminine and undecided genders.)

[Kingy]

I still maintain that slow, draggy aircraft with limited power flown into short strips demand the old method. Any wind gradient has more % effect the slower the airspeed, a prod with the stick and application of power usually does the trick... but it's the forward input on the stick that saves the day.

My experience is of biplanes and Cubs into postage stamps and I was thinking, definitely stick for airspeed but a combination of throttle and slip for ROD is what I use.

Kingy

[Sick Squid]

It always seemed strange to me from lesson One, controlling speed with attitude and rate of descent with power.

Now, with more than a few thousand hours behind me back, then I know exactly how it's done; thrust controls speed (and has a secondary effect on rate of descent) and pitch controls rate of descent (with a secondary effect on speed.)

Why is it taught differently at a basic level, because in the grand energy-equation we dance our lives around in, it is far easier long-term to have the power-speed pitch-ROD couple in your head than the one that is taught in basic training (privately, I mean: I was taught both ways, and the sponsored scheme taught me pitch-ROD from day one, all ex-mil instructors.)

It may be easier to teach one way than the other, but once one moves on to larger aircraft, then the mindset is forced to move by the very nature of their inherent aerodynamics, something that is worked-around on light aircraft, allowing for this debate.

Despite the fact that I am today flying a neutral-stability aircraft with autothrust speed control, the rules are still the same.. only difference is that I have a few ounces more capacity to look out the window.