What is the best way to control your final approach configuration

[kwokwinguk]

Hi there, I currently having some difficulties when on final approaches whether to use pitch or power to control airspeed. From my past experiences I always use pitch to control the airspeed but my instructor told me it is wrong. Use power to control airspeed and pitch to control the height.

Can someone advise me what is the best way to conduct on final approaches. I'm currenty flying on c172.

I hope I have posted on the correct forum
Many thanks,

Kwok

[mad_jock]

Its not wrong what your were doing and neither is the method the instructor is wanting you to do.

In reallity once you are a bit more experenced you will actually do a bit of both without even knowing it.

With a C172 it works reasonably well with both methods.

If your converting onto type I would question why the instructor is trying to retrain you onto a different method. What sort of instructor is the person, a new low hour guy or is he ex mil?

[Cows getting bigger]

If you are happier with pitch for speed (as you will have been taught at ex 4a), then ask your instructor to continue with that method.

[Mach E Avelli]

The pitch for speed mantra developed back in the days when most approaches were glide approaches and so power was not in the equation anyway. If you got low, you had to fix up the flight path ('cheat') with a trickle of power. This still applies for glide approaches.
But if you are being taught powered approaches, the more modern thinking is power for speed, pitch for flight path. In reality - as a previous post suggests - you will probably find that with experience you do a bit of both without even thinking about it.
If you ever get to higher performance aircraft, your instructor will insist on power to control speed on the approach. So it seems your current instructor is preparing you for better things.

[Whopity]

Think of a piece of string over your shoulder joining your right and left hand, when one moves forward the other moves back.

The question then is which one do you move first to initiate the change. Either will effect speed and rate of descent.

The concept of point and power is that you start the approach from the correct position, typically 500ft at 1 mile. If you hold a constant aspect (elevation) to the runway, the aircraft will maintain an approach path that is a line of constant elevation. If you maintain a line of constant elevation there is now only one variable, airspeed, which can be corrected with the throttle. But remember if you move one you have to move the other albeit slightly.

If you use pitch to control airspeed, it is often coarser resulting in a constantly changing aspect, which results in constant changes of power to correct the height profle. The RAF preferred the Point and Power method for flying scholarships as it prevented students going low on the approach.

If you fly the perfect approach, nobody will know which method you are using. In my experience, point and power results in a smoother approach arriving at the correct point on the runway, but not everybody would agree.

You use elevator to maintain level, you use it to maintain height in a turn, so why not use it to maintain the descent profile in a powered approach. If you have no power or insufficient power that is another matter.

[maxaoa]

Pitch for aimpoint and power for speed seems to be the most immediate way to correct mistakes on a flight path and so for this reason can be used on the final app. Power for ROD and pitch for airspeed works well but there seems to be an inherent lag as one trades against the other. Hence it works well for the part of the app that has no aim point, in my case the finals turn or base turn of an oval cct. Also as stated high perf a/c respond better to using power for speed and "pointing" at the threshold (Velocity vectors in the hud are wonderful things!!).

Doesn't answer your quandary but the great thing about avaition is that your instructor isn't always right.......just takes a long time to work it out.

[kwokwinguk]

Thankyou all,

(Mad_Jock, Few years ago when I started my training I was told that power for height and pitch for speed. Now, they are telling me power for airspeed and pitch for height (different flight schools and tell are ex airliners))

(Whopity, i will try use your mnemonic technique)

Kwok