Gettin' High.

[FlyingSportsman]

This thread is about flying :E

After bashing out some circuits on Tuesday i reviewed the video footage and noticed I seemed to be coming out high on final. I made most of the turns onto final at 1000AMSL or above, (1200AMSL circuit height) and have been advised to be about 600-800AMSL on final, so, where am I going wrong?

I like to stick tight to the 1200'QNH in the circuit, upon turning base I reduce to 1500RPM (cessna 152) and hold the nose until into the white arc and then flaps 20, trim for 70. I find that by the time i have done that, I need to be turning final and I'm still high. My landings generally come out well, but I'm bringing power out quite early and 30 degree flap every time, is this wrong/bad?

My question is, should I elongate my downwind leg? I've been shown the point at which to turn, and its marked rather well with a landmark on the ground!
Could i perhaps reduce power to less than 2200RPM in the circuit so I have less speed when turning base?

Any other suggestions?

FS :ok:

[proxus]

In a C152 Try this.

This is generally applicable to 1000' AAL.


Abeam TDZ (Touch Down Zone) reduce power to 1500-1700 RPM.
Hold the nose until you hit flap speed (white band) and drop 10° of flaps.

Once you hit 70 kts drop the nose a bit to maintain 70 kts. And don't forget the Trim.
When downwind and with the TDZ 45° off your shoulder, turn base.

Now here's the tricky part, The period from just after turning base to about mid-base is where you apply 20° of flap. A hint: if you think you're high, drop them early, if you think you're low, delay it until about midway on base. And don't forget the Trim.

Turn final and honker down the slope, here you will control your ROD with small power adjustments (if needed). Remember that for low Ground Speed (lot's of headwind) you will have to have more power during final than normally.

When you estimate that you could glide in if the engine would quit, apply 30° of flap. And don't forget the Trim.

The most rewarding thing is when you can do this excersise by reducing to about 1500 -1600 Rpm and not touch the throttle until the flare. That forces you to concentrate on when to turn and when to drop the flaps.
Turning on base is the hardest thing to estimate but generally, using the 45° angle to the TDZ works both in still air and in heavy winds.

Hope this helps you with your training.

Proxus

[Mark 1]

What you describe sounds to be as the circuit is generally taught.
A few possibilities:

Is there a wind component down the base leg? If so, try to recognise it early and widen your downwind leg accordingly.

Is your downwind to base turn a smart 30 degree banked turn?
A 20 degree bank will give you a much bigger turn radius and put you closer to final at the end of the turn.

Taking some flap at the end of the downwind leg will help to keep your circuit tight, but this is usually taught at a little later in the course and slowing too much in the circuit could cause bunching if the circuit is crowded.

It should all come with practice. If your positioning in the circuit is good then adjusting your power settings and flap selection for the conditions of the day should be sufficient to keep your approach profile stable and consistent. 1500 RPM is just a starting point, but won't be correct for every case.

[BackPacker]

From your description it looks like you're maintaining cruise power, and a speed well above Vfe, until the end of downwind, and then need to rush to get rid of all this energy. Reduce power to, say, 2000rpm when you join downwind, so that you can apply the first stage flaps not long thereafter. That should get you in a much more comfortable position by the end of downwind.

[kevmusic]

And, FWIW, I was taught that you should approach at 65 with 2 stages of flap in a C152. That would improve your ROD.

[bravobravo74]

As one of the other guys mentioned be aware that a tailwind on base will exasperate the situation that you describe.

As I'm sure you know you can't slow down, descend and keep the engine warm simultaneously to any real extent without the use of flaps. You'll want to get the barn doors into the airflow relatively soon on the base leg.

Consider reducing the power and consequently your speed in the downwind to base turn. When you roll wings level on base a further power reduction will put you into the white arc very quickly, thus allowing you to benefit from the flaps for the duration of the base leg.

Best of luck.

[foxmoth]

Are you still learning or a PPL already? The reason I ask is, if you are learning then you need to be getting this off your instructor, not applying random techniques that you get here.
Assuming you already have your PPL, the way I was taught (and teach for normal PPL circuits) is :-
Turn base, CLOSE the throttle holding the attitude, as speed falls select initial flap, at the correct approach speed lower the nose, adjust power and trim. By CLOSING the throttle you will get a faster deceleration and start down earlier. Tailwind/headwind on base is allowed for by setting lower/higher power than you would for a base with no wind component.

[Ds3]

Pretty much the same for me. I'm in a Robin hr200 so might be a bit different from the Cesna, but I've flown with a few instructors and they've all basically taught me the same approach process on a circuit of 1000ft QFE:

Turn base
Carb heat out
Throttle down
Hold attitude to hit desired speed (73 in my case)
First stage of flaps
Start descent maintaining correct speed
Turn final
Call final R/T
At around 3/400ft apply second stage flaps and carb heat in
Focus solely on maintaining speed and heading until flare

Seems to be working ok for me at least, I find it fairly easy to adjust my heading if required just using a combination of throttle and attitude. I have a set of pylons at about 150ft half way down final approach which livens things up too.

[cct]

I would be glad to be on the high side - too often I end up on the low side, which is not good. Often this is from subconsciously using the start of the runway, not the landing zone or numbers.
A bit of extra height is safer if the engine goes pop, and you can always slip off the extra height

[FlyingSportsman]

Thanks for all your comments chaps,

I am still learning, the purpose of this post was to see other people's techniques were and wack down a few notes, which i have done. I will have a chat with my instructor next week and see what he says.

When i have found something that is not absolutely straight-forward I like to get a few opinions, including my instructor's, chat to him and evaluate what I have found. It works well as it enables us to explore various situations, and why it would be better to use a certain technique at a certain time, and another at a different time.

Anyway, Cheers

FS :ok: