Hotelmode...you are absolutely right. But for the sake of a worthless discussion, what does the autopilot actually do ? Both.

Not to offend anyone but I can't believe the question was even asked in the first place.

Back to the sake !!

G'day Mates

 

Let me elaborate then.

What do you use initially to re-capture the glideslope.

IMO I use the pitch to fix small deviations from the glideslope, and power to fix small changes in airspeed.

So yes, you use both, but what do you use initially to correct for deviations was the question (maybe not formulated as such)

 

I agree with C9 - it is at least the way that has been drilled into my head - but then maybe I (we) fly our approaches in a different way than most. I do know that I need to hold somewhere around a 750 fpm rate of descent to maintain my 3.5 deg glideslope, and if I get a little low then I add POWER to correct (reduce in this scenario) my ROD and then PITCH the nose up (ever so slightly) to maintain on-speed.
But I'm no LSO!

USMCFLYR

 

To the original poster;

The only dumb question is the one not asked (unless of course you are being a smart a--). So good question.

 

I use a tiny amount of both, simultaneously.

 

Horses for courses. Personally I find it depends where your airplane falls on the power to weight / power to wing area ratio spectrum.
High P/W - power for airspeed
Low P/W - pitch for airspeed

Edit: Some very high P/W airplanes with very low aspect ratio wings (very high induced drag) can take exception to this as they fly approaches near/on the back side of the power curve.

 

ONLY in the region of reverse command (ie, low airspeed). I don't care if you are in a cessna, a cirrus, or a 757- in cruise, you pitch for altitude. I get tired of hearing people say that you pitch for airspeed while in a light aircraft- that's only true at low airspeed (Such as, Vy and below).

 

I'd hate to see you guys fly a glider.

 

I've had the luck of flying one ILS approach in a C172...and we did a CAT III autolanding. At Long Beach..

 

You did a CAT III Autoland in a C-172? Those C-172's have come a long way from the version that I used to fly!

The old pitch or power for altitude/airspeed argument....

Two guys are having that argument while taxing out to active runway. One of them can't take it any more grabs the yoke and starts flapping it in and out and yells look you idiot I am using pitch for airspeed and what happened here? Power is the only answer for airspeed....About that time the other guy grabs the yoke and starts flapping it. The first guys says what are doing!?! I'm using pitch for altitude what does it look like.

I learned to fly in sail planes. Somebody has mentioned that here. In a sail plane your initial climb is always some sort of thrusting device either a tow plane or a ground launch. After that your thrust is provided by gravity. You only have two ways to control your airspeed on a fixed glide slope in sail plane, pitch and drag. Many glider pilots set up on final and fly the glide path using half speed brakes. That gives them a cushion if they start getting low they can close the brakes and extend their glide. The same as adding or taking power off, instead you increase or decrease drag. Same basic concept though.

My big question here is how many of you actually have to think whether you are using pitch or power for glide slope control. I guess everybody learns it one way or another and by the time you are comfortable enough to actually fly an ILS in the weather it had better be second nature and totally reflexive for you or I'd say you've got some issues.