Ops Manual determines light useage
Regardless of what I think about using the position lights during daylight ops, I am required to comply with our FAA approved Ops manual. I suspect all US airlines have the same requirement as my company. Here is a copy & paste of the page in our Ops Manual:
Exterior Lights Usage:
Exterior lights should be used in accordance with the following guidance, and consistent with specific aircraft equipment, limitations, and procedures.
Phase of Flight Lights Usage:
Aircraft is powered - Navigation/Position lights
Engines running/aircraft moving:
Anti-collision lights (Beacons)
• On immediately prior to aircraft movement, or
immediately prior to engine start (if starting at gate).
Taxiing:
Taxi light
• On when moving or intending to move; off when
stopped.
Crossing a runway:
All exterior lights
• Avoid using landing lights if they will adversely affect
the vision of other pilots.
Position and hold:
All exterior lights (except landing lights)
• Avoid using strobes if they will adversely affect the
vision of other pilots.
Takeoff:
All exterior lights
• Turning on the landing lights is a signal that the
aircraft is commencing takeoff roll.
In flight (below 18,000 feet):
All exterior lights
• Conditions permitting, all exterior lights are normally
on.