Greetings Vic:> A discussion started on another forum has me puzzled. When I learned to
> fly ( Wilbur and Orville and I were buddies ) I was taught that
> power=Altitude and pitch = speed. this was the same for my Instrument
> rating. this discussion is going round and round because several people
> say they've been taught power/alt - pitch/spd for VFR VFR VFR VFR but
> the opposite for IFR.
>
> Have things changed or is someone confused here?
This is one of those debates that never seems to go away. I think that's because both sides are right--at certain times. The pitch=airspeed/power=altitude method applies to low power aircraft under MOST flight regimes. Well, let's back up a bit. In the simplest terms, pitch=airspeed/power=altitude works for all aircraft, however, it's not always the most efficient way to get the desired results. What I mean by desired results is the intended flight path and/or performance.
I'll refrain from providing pages and pages of examples for both sides of the arguments and try to just point out a few key differences (I'm one of the guys that believes it's more efficient to fly power=airspeed and pitch=altitude for ILS's). You can make up your own decision from there. 
First, let's address the aircraft component of the argument. High power/turbine aircraft are generally flown differently than low power props. The reasons there's a difference is because you have much more power and less braggy (which, for the purposes of our discussion, translates into less lift efficient) airframes. Yes, pitch will control airspeed in a jet, but you'll lose or gain altitude much faster. And because you have so much extra power at your fingertips, it's easier/more efficient to push the throttle forward to go faster.
Second, let's see how the flight regime component fits. During VFR flight in a low power airplane where a rigid approach angle isn't required (like on an ILS), it's easier to control airspeed by pitch. However, when you're on an ILS, it's more efficient to make small altitude changes using pitch. If you made small altitude changes by power alone, you'd also have to make pitch changes to maintain the glideslope (remember that a glideslope is a descent at a specific rate over the ground, so as your groundspeed changes, the rate of descent must change) because your airspeed will change/fluctuate, and because you're "juggling" more, the whole thing can get out of hand much easier--something you don't want to happen in IMC.
Now most of the flight regime examples above go out the window if you're flying jets again. If you're landing on a carrier for example, your glideslope is more of a constant rate descent because your touchdown point is also moving. Dale can probably expound on how flying carrier traps is different than an ILS in a prop plane, but the method used there is constant attitude. Attitude is kept constant and power=altitude, BUT it also controls airspeed. Again, the basic pitch=airspeed and power=altitude applies to all aircraft, which is why it's still taught from the very start, but why one is used over the other later on is a matter of efficiency as I've tried to illustrate in my examples above.
> IMHO, if I'm following a glideslope in bad weather, the last thing I
> want to be doing is chasing it by pushing the nose up and down.
You're probably flying pitch=altitude and power=airspeed even though you don't realize it because you're probably applying both at the same time or very close to it. Again, for small altitude changes on an ILS, it's more efficient to apply a pitch change.
Hope this helps!
Ben
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