On Thursday, June 4, 2015 at 10:56:21 AM UTC-6, wrote:
Arguably, the base leg may be the most important leg. A proper length base leg allows a pilot to make adjustments - shortening the base leg and turning onto the final leg early if it is perceived to low (angle too shallow) or turning away from the landing area if it is perceived you are too high.

This adjustment allowance is especially important when landing at a strange airport, or even more important when landing off field.

It should also be noted extending the base leg and performing a "button hook" landing pattern can be very dangerous - especially if there is a wind gradient or turbulence.

A disciplined, rectangular, properly spaced landing pattern is a very important judgment tool as a pilot advances to cross country flying with the risks of off field landings.

A common error is flying too close to the landing area while on the downwind leg - leaving inadequate space for a proper base leg.

Tom Knauff

I don't think I would say either rectangular patterns or a 180 turn to final is "best". The USN has certainly shown the 180 turn is best for landing on carriers and they have really tight parameters. Rectangular patterns seem to work well for others. "Best" is what works for the pilot.

I find I can make very large energy/height/distance adjustments during a 180 turn to final even with a very close-in downwind leg by simply adjusting the turn radius, adding or subtracting a little spoiler or slip. I can also make large adjustments from a rectangular pattern. However, I think the visual information needed before making those adjustments is easier to see from a close-in 180 approach.

I see many pilots making rectangular patterns arrive way too high as they turn final because they were uncertain whether they could use spoilers until they were established on final where they had good visual cues. I've also seen many pilots get in trouble at the downwind to base turn in a rectanguolar pattern when they found themselves too far from the runway. I've never seen these things happen with a simple close-in 180 turn.