When to turn base

[pv892c]

When at a class D towered airport and instructed to make "left pattern for runway 3," am I supposed to wait for the base leg turn until tower clears me for landing? This seems to be the norm, but I can't find anything in the FAR/AIM to indicate what is acceptable.

Thanks, Dave

[Nelson L.]

Do the pattern as normal - tower should clear you to land/for the option on the downwind, or somewhere along final. If you don't get a landing clearance or can't get a word in, go around. It's debatable on whether you should extend the downwind without explicit instructions to do so from the tower.

[tngarner]

I have found that a quick call to the tower "Nxxxxx, is ready to turn base" sends a nice message of wake up buddy I need direction.

[BonanzaDude]

If the tower clears you for left traffic it kind of depends where you are. You could either be entering a left downwind or left base. Enter the base turn when you are comfortable doing so. I was taught at an uncontrolled field that when the threshhold is at a 45 degree angle behind you is standard. You can use the same process when at a towered field. There are times when the controller will tell you close traffic (which means to keep the pattern tight) or to extend downwind and the controller will call your base leg. That will happen when there is another plane on final and spacing is required for both of your planes. There have been times when I am cleared to land just after contacting the tower several miles from the airport.

John

[Ryan B]

Sure you don't mean "closed" traffic? I've told a pilot to keep their base in close (more proper phraseology is "make short approach"), but I've never said "make close traffic."

Anyway, to the OP you don't need to extend or anything unless the controller says to. I tend to fly my patterns in a light GA with the wingtip over the runway from my perspective in the cockpit, or about 1/2 - 1 mile from the runway on downwind.