For landings come in slow, I aim for 150-180 speed at less than 2k above the runway (slower than 150 is OK, but if you go slower than 100-ish you start stalling (stalling = your plane isn't moving fast enough to maintain lift/fly)) , then deploy some flaps (when I land it's usually light, so I rarely use more than 2-3 tics (~50%) of flaps, and some planes only have two flap settings, full or none.), line up your runway approach and drop gear.
With speed in check, flaps and gear down, and a general idea of where the runway is below you (its OK to land off of it for now, especially if your in a nice and controlled decent to the ground) gingerly work the throttle so that you avoid stalling, but not too much that you stop your slow and controlled glide onto the runway/ground.
What you should be experiencing is your flaps slowing your plane down without any engine throttle. When you use just enough throttle to counter this drag from your flaps and maintain speed, you'll notice that your in a nice slow and controlled glide. Use too much and you will begin to gain speed and altitude. Use your throttle to speed up and slow down as needed, thus increasing and lowering the rate you are descending to the ground. At no time, other than lining up with the runway on your final approach should you tip your airplanes nose below the horizon and towards the ground (you want to be level or your nose slightly tipped up, at the very least when coming in to touch down) Also, at ~150 mph, you have a lot of runway to work with too, so don't feel rushed in hitting the runway at a certain spot.
After gliding to the ground and your wheels make contact (and keep contact) you're almost there. Just kill your throttle and fully retract/close your flaps (if you keep your flaps down while on the runway it makes you much more easily prone to flip your plane during even a slight turn on the runway). While your flaps retract, hit the space bar to apply your runway brakes. I think C and the V key are the default left and right brakes. Just tap them as needed if you still have some speed, hitting one while going too fast will cause your plane to flip. You can also use your rudder to help steer your plane on the runway, just like during take off.
If you want to show off your taxiing skills, find your way on to the reload/refuel pads at the end of each runway (you need to remain still on the pad for 30 seconds to reload).
Be mindful of the torque your engine produces in this game with single-engine aircraft (and also the lack of it when you throttle down). This is what is causing your plane to veer off course while on the runway and powering up from a dead stop. Your propeller is turning one way, pushing your engine/plane the opposite way. As you become aware of it, you'll notice it a lot more everywhere.
If you want some step by step in-flight help/instruction, there is usualy always a helpful and friendly person on the TA waiting around for someone to come in and ask them for help. If not, hunt me down this weekend, I'll be more than happy to watch you put some craters in the runway until you get it right
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