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Too high on final

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Old 19th Jul 2012, 11:07
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Too high on final

Hello!

I have a question for you experienced folks:
You are on final, full flaps set in a non-complex SEPL (C172, PA28), power idle. You judge where you will end up touching down and realize this will be too late. So you are too high on final and want to get on the correct glidepath again.

How do you do this best/what are the pros and cons?

1) Push nose down to get to the correct path again, relying on full flaps to prevent getting too fast.
2) Pull so the speed decreases and the glidpath steepens to catch the correct glidepath again.
3) Something else?

Thanks for your input!
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Old 19th Jul 2012, 11:09
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Just go around and try again?
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Old 19th Jul 2012, 11:23
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Depends on level of experience/confidence in ability - but if in doubt (as above) go around.
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Old 19th Jul 2012, 11:23
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Safest way is to just go around, but every situation is different i.e if your long final short final and depends on how high you are etc.. but if ever unsure just go around and live to fight another day
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Old 19th Jul 2012, 11:24
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3) Sideslip?
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Old 19th Jul 2012, 11:30
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When i learned i asked a similar question to which the answer was 'An experienced pilot could consider other option such as a sideslip to get back on glide path' and I said 'would that work' and the reply was 'Yes but an experienced pilot would not have allowed themselves to get into that position in the first place'

When in doubt go around.
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Old 19th Jul 2012, 11:32
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Sideslip on a Cessna with full flaps is only a good idea if you're not the owner of the airplane. On some models it's not allowed, on others not recommended. In any case it is not good for your flaps.

What works pretty well in a Cessna is pushing the nose down, it won't get much faster. With a bit of experience, you will try harder before going around. It costs time, money and makes a lot of noise. You still need good judgement though...
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Old 19th Jul 2012, 11:34
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the answer to the question is when in doubt - don't.

But it sounds to me that if you are in a 172 at idle power with full flaps and still not going to make the runway you are pretty high and that has presumably been developing for a minute or two.

Maybe you want to review your base and final technique and be more aware of what "picture" you should expect.

Last edited by Dave Gittins; 19th Jul 2012 at 11:35.
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Old 19th Jul 2012, 11:35
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If it's an older 172 with 40 degree barn doors, you won't need to side slip. Just pull the power back and it'll drop like a brick!
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Old 19th Jul 2012, 11:41
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Sideslip on a Cessna with full flaps is only a good idea if you're not the owner of the airplane. On some models it's not allowed, on others not recommended. In any case it is not good for your flaps.
Not that old chestnut again!


As for the OP, depends how confident you are chucking the aircraft around at low level, personally I'd happily throw some S-turns or a big boot of sideslip but even so there is a point where its beyond recovery and a go-around is in order....

Sopey, if you think ZV drops like a brick with full flaps you want to try a Tri Pacer witht the power off and on the draggy end of the curve....its something to behold! Great fun though!

Last edited by Unusual Attitude; 19th Jul 2012 at 11:42.
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Old 19th Jul 2012, 11:41
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Be careful what aircraft you are in.

On some small singles a sidslip with full flaps can catch you out in a big way.

I was firmly told never to do it in an AA5. Just relax, abandon it if it does not look right and go around and have another go.

C

Last edited by Corsairoz; 19th Jul 2012 at 11:42.
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Old 19th Jul 2012, 11:45
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Going around is the safest option, usually.

One "more interesting" method is to sideslip, but that option is type dependent; some types don't like that due to the flaps messing up the airflow over the tail end. I never do slipping in the TB20.

My favourite method is to do S-turns. Can scare passengers though
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Old 19th Jul 2012, 11:51
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Fishtailing, i.e. alternative fairly rapid alternating application of rudder gets rid of excess height. (Could be described as another form of sideslip, but without crossed controls) but really as generally said above, unless totally avoidable, i.e. engine failure etc., go round again.
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Old 19th Jul 2012, 11:58
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There are other things you can do other than side slip but not sure you should unless you have experience.
One is to increase your distance to touchdown by weaving left and right that also works if another aircraft on final is too close or you need more time for him to clear the runway.
The other is to do an orbit back onto final but that will depend where you are and is unlikely to be an option.
I can remember taking up a hold on final with ATC approval while they cleared some possible debris which had been noticed on the runway.
Both above are not advisable for novice pilots!
Personally I do not like to take full flap unless I am really fairly well assured of landing dragging in from miles out with full flap is not in my book a managed approach and unless full flap is recommended for the aircraft you can use the drag for coming back to your reference landing speed.
I also question the advisability of coming down the approach with a closed throttle as you have little way of knowing if there will be any power there when you do need it and with full flap and closed throttle you are limiting the options available to you to control speed and descent profile.

Pace
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Old 19th Jul 2012, 12:19
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(1) works in a 172 with a long enough runway (you're likely to end up rounding out somewhat fast and using up a fair amount of runway slowing down a few feet up).

Going around always works (provided you still have a working engine).
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Old 19th Jul 2012, 12:29
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This happened to me just a few weeks ago, when I was doing a revalidation test. I was told to do a flapless circuit and approach, and as a result misjudged things and ended up too high about half a mile from touchdown. My tester rightly ticked me off for getting too fast on the approach, but this was to get off the surplus height. We were doing the right approach speed by the time I was down to one hundred feet with a little way left to go to the numbers.

I had thought of a sideslip (which both I and the aircraft can do) but thought that this was hardly the right thing for a test. At the same time, to throw the approach away was to admit that I had got it irretrievably wrong, and this would mean a fail. So what else could be done? And come to that, where does the 'final' approach start? Half a mile out? Or when you have stabilised the speed at the right figure?

An interesting problem, and the only real answer is to get it right from the beginning. But only Allah is perfect.
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Old 19th Jul 2012, 12:30
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Two pages from "Stick and Rudder"

http://db.tt/ETS7lJcN

http://db.tt/LCMfZwhN

Last edited by rapidshot; 19th Jul 2012 at 12:32.
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Old 19th Jul 2012, 13:19
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I'd rather go with Mr. Denker on this one: More About Energy and Power [Ch. 7 of See How It Flies], certainly on an aircraft equipped with flaps (not sure whether Langewiesche isn't rather referring to a flapless aircraft, where the dive would arguably indeed not be as effective owing to the lack of additional drag).
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Old 19th Jul 2012, 13:23
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Thanks for your replies!

Going around is always the safest option, off course. But the questions was mainly, what does work better and why?

So, to sum up the answers most have suggested to put the nose down, the flaps will take care of keeping the speed low in a cessna.
The copy of Stick and Rudder explained the slower approach a bit.

I have done a correction both ways.
In my experience in a PA28 the flaps seem not to be as effective in braking as the cessna ones, meaning that I risk going over flap-speed when pointing the nose down. In addition to that you carry great speed short before (or in) the flare, which is not so good (ballooning).
The slower approach seemed to work well for me, but there is the risk you slow down too much too close to the ground.

Off course, when the final doesn't look like it can be saved, I go around. Have done it often and will do it in the future too.

Thanks again!
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Old 19th Jul 2012, 13:24
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when I was doing a revalidation test..................... to throw the approach away was to admit that I had got it irretrievably wrong, and this would mean a fail.
Before any one else says it, a revalidation is not a test and you cannot fail it.
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