Airdog, had many simillar problems myself, and got lots of useful advice at http://www.pprune.org/forums/showthr...threadid=42711

Good luck, and stick at it, it'll come.

Airdog

Welcome to the club. I don't think there is one pilot who hasn't had the experience you describe. See it for what it is, a learning experience and you will be a better pilot for it.

Good luck. :ok:

Airdog,

Yes, it happens to everyone sooner or later. I remember when I was learning my instructor even had me doing go-arounds from the hold off at about 5' (well it felt like 5'at the time).

I'd echo what evferyone else has said, but I'm afraid I have to disagree with High Wing Drifter on one point: Carb Heat - that's the FIRST thing you should do, in fact you should be putting it to cold at about 200 - 300' on short final in case you have to go around.

Brooklands

Flying for Fun

Regarding your first sentence in your last post.

Does it mean to sound so arrogant? Are you qualified to pick holes in his instructors views?

Perhaps you are an instructor yourself. If that's the case how would you feel having your views discussed openly on this forum?

Sounds to me like Airdog had a bad experience and the instructor agreed that a g/a was not an option so as not to shred the confidence out of him.

If you really would like to make a formal enquiry why not do it by Private Message.

Tory Boy,

No, it was not intended to sound arrogant at all, and if it did then I can only apoligise to anyone who took offense. I'm not an instructor, I'm a low-hours PPL.

The reason I ask is because if I'm missing an obvious reason why a go-around wouldn't be an option, then I'd like to know about it for my own education.

FFF
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My PPL instructor told me in the early stages..."Every landing is a potential go-around". If you think in that vein then you will be prepared if you have to abort. His view was people get injured or killed trying to commit themselves to a runway they arent going to make.

I have had a scary oscilation down the runway a couple of years ago and dont really want another! So far so good.......

Tory Boy,
I don't agree with what you are saying. I don't think FFF's post sounded arrogant.
I am an instructor myself and there are very few occasions where a g/a would not be possible and on a licensened airfield it is even rarer at any point excpt for maybe the end of the roll out.
The post Julian has put in, is exactly the point I would like all low houred, inexperienced students to put into practise. As I said before, if you are ready for it, then it isn't so much of an issue when you actually need to do it.

I would like to re-iterate the point about carb heat. On some a/c you have a very large accelerator pump in the carb, if the throttle is opened quickly a large amount of fuel will be dumped into the engine. If the carb heat is hot, then you are more likely to have a rich-cut due to lower air fuel ratio caused by the hot(er) air. Putting it away on finals is one way of curing this, but I would recommend that you check it just to make sure. Carb heat does make an enormous difference in power output (upto 10-20%) and in the little bug smashers you usually need as much as possible!!

I don't like the fact that an instructor would gloss over a safety point because of a fragile ego. I'm not saying that it happened here however. There may well have been valid reasons. I'm just curious to know what they are. Pure noseyness I'm afraid.

It may also be a case that the instructor didn't really say too much, and just tried to be encouraging.

I suspect A/d said to his instructor that he didn't consider a g/a an option, and as the instructor saw that he was pretty shock up, didn't want to critise. The instructor could have been thinking that the what went wrong and how to get out of it chat, was best left until the next lesson when he could demonstrate it again, and a/d was a bit more relaxed. In my opinion that would be a good call....certainly would have been more effective teaching method if the same had happened to me in my training.

Sometimes we say something to an instructor, and just because they don't disagree there an then, we tend to assume that they are agreeing with us.

Don't be too hard on this instructor, he may have done the best thing.

Dublinpilot

That was exactly what I was trying to get at. You put it far clearer than I could have though!:ok:

Say again s l o w l y, your comments about carb heat interested me. I was taught "carb heat to cold" in the last 2-300 feet, so that isn't a problem. And I know that generally carb heat results in a reduction in power. However, in a C182 that I fly the difference the carb heat control seems to make is really minimal and perhaps hardly noticeable at all. Is this likely a function of that plane's engine/carb design or something else? It seems unlikely (though not impossible obviously) that it is faulty because it has been known to clear carb ice.

drauk,
It is different for different a/c and engines. Sometimes the carb heat doesn't open as far as it's meant to, or the cold air source for the engine is warmer than it should be.

A friend was recently involved in some work on the Lotus 340R, specifically about the location of the inlet air. It turned out to be in the bottom of the engine bay where the temperature got up to 40-50 deg C. When some decent trunking was installed and a slight ram effect created, the car was dyno'd and was found to be producing 10 BHP more than usual with better throttle response.
The point of this is, if a company like Lotus can get this wrong, what about 30 year old a/c!!

Without knowing the specifics it is hard to say whether the carb ht on your 182 is functioning correctly or not. I've never flown a 182 so I'm not au fait with it's handbook. Personally I like to see at least a 100rpm drop and a positive change in engine note and leave it for at least 10 elephants. This will ensure you don't just check the action, but also whether you actually have carb ice.

One question for everybody, where are you most likely to get carb ice forming? (I'm just interested to see the replies as I never get the correct answer from students!)

drauk - only flown a C182 once so far (as my last 2 planned complex differences training trips have been weathered off), but have done some ground school type work with an instructor on this. Fairly obviously, you won't see a variation in the RPM due to the CSU when operating carb heat, so all there will be is a slight change in manifold pressure. Due to the way that carb heat operates, it actually doesn't have a great effect on manifold pressure. I'm not claiming expert status on this and am ready for http://www.click-smilies.de/sammlung...smiley-005.gif and the great and good telling me I'm talking like this http://www.click-smilies.de/sammlung...smiley-025.gif :D

Not sure what answer you're looking for, SAS. Are you looking for the temperature/humidity conditions where it's mostly likely to form? The phase of flight when it's most likely to form? Where abouts, physically, in the carb it's most likely to form?

I could have a go at answering any of those, but with a comment like "I never get the correct answer" I'm not sure I dare! ;)

FFF
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PS - Shouldn't some of the later posts on this thread be on the carb heat thread instead?

It's not meant to sound facetious, I'm just doing my own quick research. I actually mean the phase of flight.

Yep, I also think they should be jumped across to the carb heat thread.

Circuit Basher, when you are doing your preflight carb heat check, then you will see an RPM drop despite the CSU. This is because the the RPM is outside of its operating range. There is only a limited angle that the prop can move in, basically the prop will be as fine as possible.
In flight, you will get an initial change of RPM with the application of carb heat this is due to the loss of power and the lag in the response of the CSU in fining off the prop to keep it at the required RPM.

I would think it must be difficult to detect carb icing on a constant speed prop aircraft, because the governor will initially try to compensate and maintain the RPM. It should show up in airspeed eventually...

I read this in some accident reports on engine failures on twins. When doing twin training, the engine gets shut down (by the instructor) so you can see it clearly. But in reality, it often happens slowly, with the prop governor compensating and masking the problem for a while...

ALL engines should be fuel injected. Carb icing is horrid, and the need to fiddle with the carb heat is a huge distraction to safely operating the aircraft.

IO540, couldn't agree with you more.
A CSU can make carb icing more insidious than usual with the very qualities of the unit, masking the problem. I still don't understand why any engines are still carb'd. You cannot even buy a new car without fuel injection anymore. This is a case when the CAA and other bodies hold up the development of a/c to a huge degree, by having such rediculous certification costs. Why do virtually no light a/c have silencers fitted, electronic ignition (Magnetos for god's sake!!!) etc.etc..I know it is said that what we have is tried and tested, so why are there still A/D's coming out on a/c and engines? IO540 I bet you know what I'm talking about!!

Bounces
 

Airdog

It may cheer you up to watch the films of today's Concorde landings at Heathrow. Especially number 2 I think :ok:

Drauk,

You will not notice the difference between carb heat on/off in an aircraft with a CSU due to the CSU.

Anyone who states something different has obviously not got experience in flying this combination of engine/prop.

FD

FD, have you ever flown a TB10? you certainly will get a momentary change of RPM on application of carb heat. That's certainly what happened today and every other day I've flown a machine with a CSU, obviously apart from turbines and fuel injection.

Yup done that, got the T-shirt.

Have also flown other CSU equipped singles and twins from Socata; Cessna; Piper and Beech.

And on all of those you can juggle the carb heat or alternate air to your heart's content without it making a dicky bird difference to the RPM.

That is the essence of the CSU. If your TB10's CSU can not cope with the difference in power due to the application of carb heat then it may well be that there is something wrong with it.

Those who have experience flying twins will know that even if you throttle one engine back to zero trust and open the other engine up for simulated engine failures there will be no changes in RPM as can be witnessed by the props staying in sync.

FD