This regulation isn’t too long, so you should probably read it on the ecfr.gov website, but there are parts that show up on most of the exams, so they are summarized here.
Aircraft accident means an occurrence associated with the operation of an aircraft which takes place between the time any person boards the aircraft with the intention of flight and all such persons have disembarked, and in which any person suffers death or serious injury, or in which the aircraft receives substantial damage. For purposes of this part, the definition of “aircraft accident” includes “unmanned aircraft accident”.
Civil aircraft means any aircraft other than a public aircraft. Public aircraft means an aircraft used only for the United States Government.
Fatal injury means any injury which results in death within 30 days of the accident.
Incident means an occurrence other than an accident, associated with the operation of an aircraft, which affects or could affect the safety of operations.
Operator means any person who causes or authorizes the operation of an aircraft, such as the owner, lessee, or bailee of an aircraft.
Serious injury means any injury which: (1) Requires hospitalization for more than 48 hours, commencing within 7 days from the date of the injury was received; (2) results in a fracture of any bone (except simple fractures of fingers, toes, or nose); (3) causes severe hemorrhages, nerve, muscle, or tendon damage; (4) involves any internal organ; or (5) involves second- or third-degree burns, or any burns affecting more than 5 percent of the body surface.
Substantial damage means damage or failure which adversely affects the structural strength, performance, or flight characteristics of the aircraft, and which would normally require major repair or replacement of the affected component.
Not considered “substantial damage” for the purpose of this part:
Engine failure or damage limited to an engine if only one engine fails or is damaged, bent fairings or cowling, dented skin, small punctured holes in the skin or fabric, ground damage to rotor or propeller blades, and damage to landing gear, wheels, tires, flaps, engine accessories, brakes, or wingtips.
Unmanned aircraft accident when the system is activated with the purpose of flight and the time that the system is deactivated at the conclusion of its mission, in which any person suffers death or serious injury or the aircraft has a maximum gross takeoff weight of 300 pounds or greater and sustains substantial damage.
The operator of any civil aircraft, or any public aircraft not operated by the Armed Forces or an intelligence agency of the United States, or any foreign aircraft shall immediately, and by the most expeditious means available, notify the nearest National Transportation Safety Board (NTSB) office,1 when:
An aircraft accident or any of the following listed serious incidents occur:
Flight control system malfunction or failure;
Inability of any required flight crewmember to perform normal flight duties as a result of injury or illness;
Failure of any internal turbine engine component that results in the escape of debris other than out the exhaust path;
Aircraft collision in flight;
Damage to property, other than the aircraft, estimated to exceed $25,000 for repair (including materials and labor) or fair market value in the event of total loss, whichever is less.
For large multiengine aircraft
• In-flight failure of electrical systems which requires the sustained use of an emergency bus powered by a back-up source such as a battery, auxiliary power unit, or air-driven generator to retain flight control or essential instruments;
• In-flight failure of hydraulic systems that results in sustained reliance on the sole remaining hydraulic or mechanical system for movement of flight control surfaces;
• Sustained loss of the power or thrust produced by two or more engines; and
• An evacuation of an aircraft in which an emergency egress system is utilized.
Release of all or a portion of a propeller blade from an aircraft, excluding release caused solely by ground contact;
A complete loss of information, excluding flickering, from more than 50 percent of an aircraft’s cockpit displays known as:
• Electronic Flight Instrument System (EFIS) displays;
• Engine Indication and Crew Alerting System (EICAS) displays;
• Electronic Centralized Aircraft Monitor (ECAM) displays; or
• Other displays of this type, which generally include a primary flight display (PFD), primary navigation display (PND), and other integrated displays;
Airborne Collision and Avoidance System (ACAS) resolution advisories issued when an aircraft is being operated on an instrument flight rules flight plan and compliance with the advisory is necessary to avert a substantial risk of collision between two or more aircraft.
Damage to helicopter tail or main rotor blades, including ground damage, that requires major repair or replacement of the blade(s);
Any event in which an operator, when operating an airplane as an air carrier at a public-use airport on land:
• Lands or departs on a taxiway, incorrect runway, or other area not designed as a runway; or
• Experiences a runway incursion that requires the operator or the crew of another aircraft or vehicle to take immediate corrective action to avoid a collision.
An aircraft is overdue and is believed to have been involved in an accident.
Preservation of Aircraft Wreckage, Mail, Cargo, and Records
The operator of an aircraft involved in an accident or incident is responsible for preserving to the extent possible any aircraft wreckage, cargo, and mail aboard the aircraft, and all records, including all recording mediums of flight, maintenance, and voice recorders, pertaining to the operation and maintenance of the aircraft and to the airmen until the Board takes custody thereof or a release is granted.
Such wreckage, mail, or cargo may not be disturbed or moved except to the extent necessary:
• To remove persons injured or trapped;
• To protect the wreckage from further damage; or
• To protect the public from injury.
Where it is necessary to move aircraft wreckage, mail or cargo, sketches, descriptive notes, and photographs shall be made, if possible, of the original positions and condition of the wreckage and any significant impact marks.
Reports and Statements To Be Filed
(a) Reports. The operator shall file a report on Board Form 6120.5 within 10 days after an accident, or after 7 days if an overdue aircraft is still missing. A report on an incident for which immediate notification is required shall be filed only as requested by an authorized representative of the Board.