Senna,
I've never done any real short/rough strip work (unless you count the runways at White Waltham as rough!). But the general idea is that, for take-off, follow the technique in the POH. This will usually involve full back elevator during the take-off roll, and lowering the nose as soon as airbourne in order to gain speed and avoid the stall. Landing will usually be slower than normal, sometimes on the back side of the power curve, involving lots of power to couteract the drag, and a flatter approach than you're used to. But the POH will take precendence over everything I've said - I've never flown a C172, so I make no guarantees that the technique I've described is appropriate.
You should have covered all this for your PPL - if not, read the POH, and get an instructor to run through it with you in the air. I doubt that practicing over here will prepare you for the real thing (it certainly didn't prepare me for the one rough field I've flown into), but at least you'll know what to do, even if not what to expect.
Altitude flying is something I do know about, having spent 100 hours or so flying around the moutains in Arizona.
Take-off and landing really shouldn't be a problem, so long as you do your performance checks. If you're flying a type such as a C172 you should find you have performance graphs in the POH - use them for every flight into conditions you're not used (that includes any combination of weights/altitudes/temps/winds you're not used) and you'll be fine. It will take longer to accelerate on take-off, don't be tempted to rotate too soon. And both the take-off and landing will be at a higher ground-speed than you're used to - trust your ASI and fly the attitude, ignore what your brain tells you about your speed.
(If you're flying an aircraft without performance graphs, as I was, there are two techniques you can use for guestimating the performance. First, look at the graphs for a different type, and apply similar percentage increases for similar differences. Second, and probably more importantly, talk to the locals!)
In the cruise, you'll need more throttle to get the same amount of power at higher altitudes. As the air gets thinner, you need a greater volume of air to get the same mass of air. If you don't open the throttle, you'll notice the RPM dropping off. Unfortunately, just increasing the throttle to maintain RPM doesn't quite work - the thinner air provides less resistance to the prop, so in order to set the same amount of power as you had at lower levels, you'll actually need a higher RPM at higher levels, and therefore an even greater increase in throttle setting than you would to just maintain RPM.
As a guide, I used to start opening the throttle at about 4000'. By about 7000' I was at full throttle - any further increase in altitude and I would have to accept a decrease in power.
(It's no problem if you have a constant speed prop - you can set the power on the manifold pressure guage, and the prop will coarsen as necessary. You'll still run out of throttle at about 7000', but you'll be able to set it much more accurately below this.)
Leaning also becomes more important. Always lean in the cruise. You'll need to get some guidelines from the instructors as to whether to lean for take-off, I was told to lean the Super Cub for take-off, but not the Warrior or Arrow, and that seemed to work for me.
Also, the difference between IAS and TAS starts becoming more relevant at these altitudes - if you don't convert IAS to TAS when doing flight planning normally, you might like to start, otherwise you'll find that you're consistently faster than expected on your ded reckoning.
Far more important is the effect of winds blowing over mountains. The general rules are: 1) Never fly close to mountains on the down-wind side - the down-draughts can make the aircraft uncontrollable, and 2) Always make sure you've got enough space between you and the mountain to do a 180-degree turn and get out.
I should probably emphasise the importance of understanding these winds a bit more: take-off and landing performance is easy to do properly, and unlikely to kill you. Not understanding how the engine and prop behave at altitude might mess up your navigation a bit, but won't kill you. Failing to understand the winds will kill you if you get it wrong on a windy day. Always be aware of where the wind is from, how it's going to be affected by the terrain, and how to get out of trouble if you've got the winds wrong.
I'm sure you'll have a great time there - I'd like to get out there myself some time. Make sure we get a full report!
FFF
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