FD, most of the aircraft you've mentioned don't have a carb air system, probably because they have fuel injection.:p

On higher powered a/c the affect is masked due to the percentage power loss being smaller. I've noticed this effect on nearly all a/c I've flown with a CSU, and that's definately more than a couple, it might be very minor, but there is a small initial difference, note I don't say the the RPM drops for any length of time, but like all mechanical systems the CSU bob weights do take a (small) amount of time to react to allow the pitch to fine slightly and therefore regain the specified RPM.

Sorry mate,

Those that don't have carb heat and are fuel injected have alternate air.

The difference in power delivered by flying assymetric at zero trust/max continuous is many multiples greater than that generated by applying carb heat.

I think what you are stating is factually incorrect.

FD

Airdog,
Congrats on your solo. Welcome to the club. A go-round may not have been possible simply because you might have been just a bit too overloaded with the bounce to get it right. Absolutely no disrespect to you, you've just begun this great hobby/career.
I would put it behind me, take the lessson learnt and make sure you nail the speed next time and remember the go-round drill if required.
Recovering from a bounce is possible, I've done it many times. Just add a smidge of power to check the RoD and let it settle back on to the runway again (after removing the power). If the thermals are a bastard, then fly earlier in the day. Summer in SA is hot as you well know. :D

I've bounced every thing from Cherokees to Dash 8's. It's no bother really. I assume that 1 out of 10 landings will be ordinary. (perhaps I should say "touch downs"). If I am on speed, correctly configured with an acceptable RoD and landing on the correct part of the runway and the aircraft is serviceable after the landing, it's a good one. :D

I didn't expect to see an RPM drop necessarily (because of the CSU), but regardless of that ongoing debate my point was that I don't notice any change in performance and since attitude + power = performance I was wondering about the drop in power. As a practical solution I tend to use the carb heat quite liberally and leave it on for at least 20 seconds, to detect an increase in peformance when it is returned to cold.

More generally, given the high susceptability of a 182 to generate carb ice I am basically wondering about the merits or not of using it even more/more often. If there is no appreciable power drop why not use it, for example, constantly when in cloud (a time when carb ice is both more likely and more dangerous)? Is the lack of filtering a real concern here?

Sorry Dutch, but your comment about Zero thrust and Full throttle engines staying in synch, is simply not true. A CSU or governor has stops, and an engine/prop combination that will produce 350HP on one side is simply not going to remain at 2575 RPM when it has 12 inches of manifold pressure applied. Every instrument renewal I do reminds me of this fact. I use these examples as they are from the a/c I usually fly.

FD,
As Dale says, there is no way an engine at 12" manifold is going to keep a specified RPM. The prop will be fully fine on the pich stops. This usually happens at around 19-20" inches as you reduce power. The prop will then act like a fixed unit, because essentially that is what it has become.

Alternate air and carb heat are NOT the same thing. I don't know exact figures, but I would doubt that the power differential between 'normal' and alternate air would be the same as with carb heat hot or cold.
FD if you think about the way a CSU operates, then you will see what I am saying HAS to be true. As I stated before, all mechanical devices have some lag in them so when the power is reduced the prop has to become finer to compensate and keep the same RPM, this takes a finite amount of time so the RPM initally will drop and then recover to the original setting. This may only take 1/4-1/2 of a second, but it is noticable.

Drauk, usually you won't have a problem with non filtered air in flight unless you fly through a dust storm! The problem usually comes with taxiing with carb heat on. I would stick to the principle that when in cloud I would use carb heat more often, but not constantly, just be very aware that it can creep up on you. Generally an engine will only stop due to carb ice when the throttle is closed, as Whirly has already alluded to, but obviously it can happen at other times. At large throttle openings it is less likely for carb ice to form due to the speed of the airflow and the fact that there isn't as much of a pressure drop behind the throttle butterfly. (I still don't understand why we don't use flat-slide carbs on a/c, any engineers out there know the reason? Or is it just a 'certifcation issue' as per usual?)

BRL, shouldn't some of the replies to this thread be moved across to the carb heat in the circuit thread? If this is possible of course!

Dale,

That is not my experience but happy to concede that this can be the case in some engine/prop/airframe set ups.

SASlowly,

I have never noticed that but will pay more attention next time.

FD

Carb icing in a normally aspirated engine with a constant speed prop will be evident by loss of manifold pressure.

Chuck

Sorry to have taken so long to report back on follow-up developments but have been away for a few days.

I have flown on two occasions (neither solo) since that bouncing scare, the first two days later and the second four days after that.
Both times we did circuits, practising touch-and-goes (with and without flaps) and go-arounds.

My instructor put me through several situations where I had to very quickly decide whether or not to do a G/A. These included coming in a bit high or fast, balooning before touchdown and missing the runway. All of this was beneficial. I think I made the right calls on the go-arounds and also managed to land fairly smoothly (no major bounces).

Of course we discussed at some length the whole G/A issue and the causes/ recovery of bouncing/balooning.
These are the main points:
My instructor emphasized that the go-around is always an option. It should preferably be initiated before touchdown.
It can be quite a dangerous manouevre if initiated after touchdown, so if a bounce occurs you muct decide very quickly whether to go around or whether to recover and land.
If the bounce is not too severe, the recovery can be safely employed by correctly re-positioning the aircraft for touchdown and landing in the usual manner by holding off with back pressure on the control stick. Never allow the nose to drop.
If the bounce is severe, go around.

My problem was that I while I was coming in a bit fast I did not think this warranted a go-around. First mistake, particularly with the winds as tricky as they were.
Second mistake: I did not properly recover from the first bounce. It took me until the third bounce, and in potentially a very dangerous situation, to finally recover correctly. I can only put this down to lack of experience.

No doubt I have learnt some valuable lessons and, hopefully, will be a better pilot for it. Thanks to all on this forum for their advice and encouragement. I look forward to my next solo although I must admit some trepidation still lingers.

Airdog

AD,

Good to read that you are back in the saddle.

You write:

but just remember that you
1. Have already done the deed (of flying solo) and
2. When the instructor lets you go he/she is convinced you are up to the job.

Have fun and keep us posted!

FD

Don't worry I was sitting at the hold at a certain airport and saw an A320 put in a bit of a rough landing. It just happens, even to those wth 1000's of hours.

Remember Keep calm:ok:

Airdog, stick with it - if you ever meet anyone who claims to have never ballooned/bounced, I would speculate that they are probably liars and are not worth talking to.

Interesting about the 172 and its landing charactoristics though . I learned in 152's and when I got my ticket and had a go in 172's, I made what I am told was a common mistake and assumed that as a bigger plane, it needed a faster approach/landing speed (despite what the books say!!) So, I made approaches at 70kts and guess what, the damned thing would not land. Luckily, I was on a field with a long long runway and got away with it. When I did my first night approach with an instructor at 70kts, he tore me off a strip for being stupid and ignoring the books.

G-Foxtrot Oscar 69 & phnuff,

and
Well said, Absolutely true!

I recently flew Mrs G to a meeting in a Warrior that I fly from time to time.

It was, fortunately, a large strip and there was a fairly healthy crosswind - just within limits – but my landing was SO bad that Mrs G (who is normally an extremely placid, calm and experienced passenger) turned to me and said “what the hell was that?”!!!

Afterwards, whilst licking my wounds, I realised that I had screwed it up, simply because I was far, far too fast on the approach (if I’m honest I was probably about 75 – 80 knots over the threshold). Luckily I recovered the landing without incident BUT I was reminded of two very valuable lessons:

1. I had done a ‘seat of the pants’ approach – I foolishly thought that the speed ‘felt’ right – it was slow compared to the 74 and I didn’t keep a close enough eye on the ASI.

2. I was in ‘Private Flying Committed to Land’ mode – i.e. a G/A didn’t enter my head until I thought “wwwwwwwwooooooooooooooaaaaaaaaaaaaaaaaoh shhhhhhh11111111111ttttttt, I’ve screwed this one up” – if I’d done the same thing at work I’d have gone around without even thinking about it – interestingly, even now I still don’t know why I was mentally so committed to landing the thing.

Whilst Mrs G was at the meeting. I climbed back into the a/c and did 6 circuits, this time at the CORRECT speed and each was OK.

When it was time to fly home, Mrs G (ever the school maam) said, “well, I hope that this landing will be better”, to which I replied, “it’s OK, I’ve been practising”. . . . .
:ooh: :ouch: :ooh: :ouch: