Thinking hard about safety, here's a transcript from one of Jason Miller's weekly "Finer Points" podcasts. Click the title above to listen to the audio as you read it. (http://cdn.libsyn.com/jmiller/clearing-turns-jason-miller.mp3)
...In this episode, I'm going to lay out some procedures that I recommend for clearing turns.
One thing that will help you become diligent about this procedure is to do it the same way every time.
Now, the FAA gives us a choice about clearing turns. You have to turn 180 degrees, but you can either do this in one turn, or you can turn 90º and back to your original heading. Either way, here's a procedure to help you become diligent.
Always start by first turning to the left. Remember, if there's any aircraft overtaking you, they're going to overtake you on the right side. So always begin your clearing turns with a left turn.
If you're in a high-wing airplane, remember to lift the wing and clear the blind spot before you turn in that direction.
During the turn, make sure you're scanning the air using the FAA-recommended technique of scanning UP and DOWN columns of the sky, then move over 10º and repeat.
If you're lucky enough to have windows in the back of your airplane..., make sure that you're using them. Put your head on a swivel. Turn your head and look through all those windows and make sure that there IS no traffic in the area.
When you reach the 90º point, reduce power to the setting required for the maneuver. This will allow your aircraft to slow during the rest of the turn, whether you continue on a 180º turn or if you go back to your original heading. This will keep your airplane in the vicinity of the airspeed you just cleared.
You do have to divide your attention and make sure you're not losing altitude.
Once you're back on your original heading, it's time to do your flow check, perform the maneuver, recover, and fly away safely.
If you're a student pilot, adopt this technique.
If you're a private pilot, we all have biennial flight reviews. Make sure you don't forget the clearing turns.
I hate hearing about midair collisions. And I hope that you'll all adopt this technique to prevent ever having one yourself.
----The Finer Points Episode #47, "It's Severe Not to Clear." Jason Miller