On Sun, 1 Apr 2007 12:58:40 +1200, "Richard"
wrote:

Do pilots follow the white lines on taxi-ways or swing wide as truck/trailer
drivers must do?

Depends on the aircraft. Some, like the 757, have the nose gear so
far behind the flight deck that the crew must adapt. They allow the
nose to travel well beyond the centerline when turning. On small
aircraft, the nose is simply kept on the line.

Centerlines are simply an aid to keep you to the center of the
pavement, helping to ensure clearance to the sides. In some
circumstances, such as taxiing between rows of parked aircraft, a
centerline makes maintaining equal clearance to the sides much easier
than trying to judge inconsistent edges. Each pilot must learn where
the centerline falls in the field of vision on a particular aircraft.
Some tail draggers need to swerve back and forth, as the pilot has
poor forward vision with the tail on the ground.

When snowbanks are present, all bets are off.

Are they just a night aid?

Not at all.