Sec. 23.775 - Windshields and windows.
(a) The internal panels of windshields
and windows must be constructed of a nonsplintering material, such as
nonsplintering safety glass.
(b) The design of windshields, windows,
and canopies in pressurized airplanes must be based on factors peculiar to
high altitude operation, including --
(1) The effects of continuous and cyclic
(2) The inherent characteristics of the
material used; and
(3) The effects of temperatures and
(c) On pressurized airplanes, if
certification for operation up to and including 25,000 feet is requested,
an enclosure canopy including a representative part of the installation
must be subjected to special tests to account for the combined effects of
continuous and cyclic pressurization loadings and flight loads, or
compliance with the fail-safe requirements of paragraph (d) of this
section must be shown.
(d) If certification for operation above
25,000 feet is requested the windshields, window panels, and canopies must
be strong enough to withstand the maximum cabin pressure differential
loads combined with critical aerodynamic pressure and temperature effects,
after failure of any load-carrying element of the windshield, window
panel, or canopy.
(e) The windshield and side windows
forward of the pilot's back when the pilot is seated in the normal flight
position must have a luminous transmittance value of not less than 70
(f) Unless operation in known or
forecast icing conditions is prohibited by operating limitations, a means
must be provided to prevent or to clear accumulations of ice from the
windshield so that the pilot has adequate view for taxi, takeoff,
approach, landing, and to perform any maneuvers within the operating
limitations of the airplane.
(g) In the event of any probable single
failure, a transparency heating system must be incapable of raising the
temperature of any windshield or window to a point where there would be --
(1) Structural failure that adversely
affects the integrity of the cabin; or
(2) There would be a danger of fire.
(h) In addition, for commuter category
airplanes, the following applies:
(1) Windshield panes directly in front
of the pilots in the normal conduct of their duties, and the supporting
structures for these panes, must withstand, without penetration, the
impact of a two-pound bird when the velocity of the airplane (relative to
the bird along the airplane's flight path) is equal to the airplane's
maximum approach flap speed.
(2) The windshield panels in front of
the pilots must be arranged so that, assuming the loss of vision through
any one panel, one or more panels remain available for use by a pilot
seated at a pilot station to permit continued safe flight and landing.
[Doc. No. 4080, 29 FR 17955, Dec. 18, 1964, as
amended by Amdt. 23-7, 34 FR 13092, Aug. 13, 1969; Amdt. 23-45, 58 FR
42165, Aug. 6, 1993; 58 FR 51970, Oct. 5, 1993; Amdt. 23-49, 61 FR 5166,
Feb. 9, 1996]