§  17.45   Temporary warning lights.

   During construction of an antenna structure, for which red obstruction
   lighting is required, at least two 116- or 125-watt lamps (A21/TS)
   enclosed in aviation red obstruction light globes, shall be installed
   at the uppermost point of the structure. The intensity of each lamp
   shall not be less than 32.5 candelas. In addition, as the height of the
   structure exceeds each level at which permanent obstruction lights will
   be required, two similar lights shall be installed at each such level.
   These temporary warning lights shall be displayed nightly from sunset
   to sunrise until the permanent obstruction lights have been installed
   and placed in operation, and shall be positioned so as to insure
   unobstructed visibility of at least one of the lights at any normal
   angle of approach. If practical, the permanent obstruction lights may
   be installed and operated at each required level as construction
   progresses.

   [ 32 FR 11273 , Aug. 3, 1967, as amended at  39 FR 26157 , July 17, 1974;
    42 FR 54826 , Oct. 11, 1977]