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