Bird Strike Regulations
FAA Rules for Bird Strike
14 CFR FAR 25.631: Bird Strike.
The empennage structure must be designed to assure capability of continued safe flight and landing of the airplane after impact with an 8 lb bird when the velocity of the airplane is equal to VC at sea level.
14 CFR FAR 25.775: Windshields and windows.
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 4lb bird when the velocity of the airplane is equal to the value of VC, at sea level.
14 CFR FAR 25.571: Damage-tolerance and fatigue evaluation of structure.
Impact with a 4-pound bird when the velocity of the airplane is equal to VC at sea level or 0.85 VC at 8,000 feet, whichever is more critical. The damaged structure must be able to withstand the static loads (considered as ultimate loads) which are reasonably expected to occur on the flight. Dynamic effects on these static loads need not be considered. Corrective action to be taken by the pilot following the incident must be considered. If significant changes in structural stiffness or geometry, or both, follow from a structural failure or partial failure, the effect on damage tolerance must be further investigated
14 CFR FAR 33.76: Bird Ingestion Aircraft Engines.