SUBPART D – DESIGN AND CONSTRUCTION
Large Aeroplanes (CS-25) · CS-25 · CS 25.601 – CS 25.899
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CS 25.601 General
The aeroplane may not have design features or details that experience has shown to be hazardous or unreliable.
CS 25.603 Materials
(See AMC 25.603; for composite materials, see AMC 20-29; for use of glass in passenger cabins, see AMC No 2 to CS 25.603(a)) The suitability and…
AMC No 1 to CS 25.603(a) Suitability and durability of materials — Experience or tests
To show compliance with CS 25.603 and CS 25.605, applicants may use previous applicable experience and/or tests together with material specifications and…
AMC No 2 to CS 25.603(a) Suitability and durability of materials — Large glass items
General This AMC defines acceptable minimum performance standards for the specific case of large glass items used as an interior material in passenger…
CS 25.605 Fabrication methods
(See AMC 25.605) (a) The fabrication methods used (i.e. the manufacturing and assembly methods, including consideration of the materials and material…
AMC 25.605(a) Fabrication methods — Approved process specifications
CS 25.607 Fasteners
(See AMC 25.607) (a) Each removable bolt, screw, nut, pin or other removable fastener must incorporate two separate locking devices if – (1) Its loss…
CS 25.609 Protection of structure
(See AMC 25.609) Each part of the structure must- (a) Be suitably protected against deterioration or loss of strength in service due to any cause…
CS 25.611 Accessibility provisions
Means must be provided to allow inspection (including inspection of principal structural elements and control systems), replacement of parts normally…
CS 25.613 Material strength properties and Material Design Values
(See AMC 25.613) (a) Material strength properties must be based on enough tests of material meeting approved specifications to establish design values on…
AMC 25.613 Material strength properties and material design values
CS 25.619 Special factors
The factor of safety prescribed in CS 25.303 must be multiplied by the highest pertinent special factor of safety prescribed in CS 25.621 through CS…
CS 25.621 Casting factors
(see AMC 25.621.) (a) General. For castings used in structural applications, the factors, tests, and inspections specified in sub-paragraphs (b) through…
CS 25.623 Bearing factors
Except as provided in sub-paragraph (b) of this paragraph, each part that has clearance (free fit), and that is subject to pounding or vibration, must…
CS 25.625 Fitting factors
For each fitting (a part or terminal used to join one structural member to another), the following apply:
CS 25.629 Aeroelastic stability requirements
(See AMC 25.629) (a) General. The aeroelastic stability evaluations required under this paragraph include flutter, divergence, control reversal and any…
CS 25.631 Bird strike damage
(See AMC 25.631) The aeroplane must be designed to assure capability of continued safe flight and landing of the aeroplane after impact with a 4 lb bird…
CS 25.651 Proof of strength
Limit load tests of control surfaces are required. These tests must include the horn or fitting to which the control system is attached.
CS 25.655 Installation
Movable tail surfaces must be installed so that there is no interference between any surfaces when one is held in its extreme position and the others are…
CS 25.657 Hinges
For control surface hinges, including ball, roller, and self-lubricated bearing hinges, the approved rating of the bearing may not be exceeded.
CS 25.671 General
(See AMC 25.671) (a) Each flight control system must operate with the ease, smoothness, and positiveness appropriate to its function.
CS 25.672 Stability augmentation and automatic and power-operated systems
If the functioning of stability augmentation or other automatic or power-operated systems is necessary to show compliance with the flight characteristics…
CS 25.675 Stops
Each control system must have stops that positively limit the range of motion of each movable aerodynamic surface controlled by the system.
CS 25.677 Trim systems
Trim controls must be designed to prevent inadvertent or abrupt operation and to operate in the plane, and the sense of motion, of the aeroplane.
CS 25.679 Control system gust locks
(See AMC 25.679) (a) There must be a device to prevent damage to the control surfaces (including tabs), and to the control system, from gusts striking…
CS 25.681 Limit load static tests
Compliance with the limit load requirements of this CS-25 must be shown by tests in which – (1) The direction of the test loads produces the most severe…
CS 25.683 Operation tests
It must be shown by operation tests that when portions of the control system subject to pilot effort loads are loaded to 80% of the limit load specified…
CS 25.685 Control system details
(See AMC 25.685) (a) Each detail of each control system must be designed and installed to prevent jamming, chafing, and interference from cargo…
CS 25.689 Cable systems
Each cable, cable fitting, turnbuckle, splice, and pulley must be approved.
CS 25.693 Joints
Control system joints (in push-pull systems) that are subject to angular motion, except those in ball and roller bearing systems must have a special…
CS 25.697 Lift and drag devices, controls
Each lift device control must be designed so that the pilots can place the device in any takeoff, en-route, approach, or landing position established…
CS 25.699 Lift and drag device indicator
There must be means to indicate to the pilots the position of each lift or drag device having a separate control in the cockpit to adjust its position.
CS 25.701 Flap and slat interconnection
(See AMC 25.701) (a) Unless the aeroplane has safe flight characteristics with the flaps or slats retracted on one side and extended on the other, the…
CS 25.703 Take-off warning system
(See AMC 25.703) A take-off warning system must be installed and must meet the following requirements:
CS 25.705 Runway overrun awareness and alerting systems
(See AMC 25.705) A runway overrun awareness and alerting system (ROAAS) must be installed.
CS 25.721 General
(See AMC 25.963(d)) (a) The landing gear system must be designed so that when it fails due to overloads during take-off and landing, the failure mode is…
CS 25.723 Shock absorption tests
(See AMC 25.723) (a) The analytical representation of the landing gear dynamic characteristics that is used in determining the landing loads must be…
CS 25.729 Extending and retracting mechanisms
(See AMC 25.729) (a) General. For aeroplanes with retractable landing gear, the following apply:
CS 25.731 Wheels
Each main and nose wheel must be approved. The maximum static load rating of each wheel may not be less than the corresponding static ground reaction…
CS 25.733 Tyres
When a landing gear axle is fitted with a single wheel and tyre assembly, the wheel must be fitted with a suitable tyre of proper fit with a speed rating…
CS 25.734 Protection against wheel and tyre failures
(see AMC 25.734) The safe operation of the aeroplane must be preserved in case of damaging effects on systems or structures from:
CS 25.735 Brakes and braking systems
(See AMC 25.735) (a) Approval. Each assembly consisting of a wheel(s) and brake(s) must be approved.
AMC 25.735 Brakes and Braking Systems Certification Tests and Analysis
CS 25.745 Nose-wheel steering
(See AMC 25.745) (a) The nose-wheel steering system, unless it is restricted in use to low-speed manoeuvring, must be so designed that exceptional skill…
AMC 25.745(a) Nose-wheel steering
CS 25.771 Pilot compartment
Each pilot compartment and its equipment must allow the minimum flight crew (established under CS 25.1523) to perform their duties without unreasonable…
CS 25.772 Pilot compartment doors
For an aeroplane that has a lockable door installed between the pilot compartment and the passenger compartment:
CS 25.773 Pilot compartment view
(See AMC 25.773) (a) Non-precipitation conditions. For non-precipitation conditions, the following apply:
AMC 25.773 Pilot compartment view
AMC 25.773(b)(1)(ii) Pilot compartment view in icing conditions
CS 25.775 Windshields and windows
(See AMC 25.775) (a) Internal panes must be made of non-splintering material.
CS 25.777 Cockpit controls
Each cockpit control must be located to provide convenient operation and to prevent confusion and inadvertent operation.
AMC 25.777(c) Full and unrestricted movement of cockpit controls
CS 25.779 Motion and effect of cockpit controls
Cockpit controls must be designed so that they operate in accordance with the following movement and actuation:
CS 25.781 Cockpit control knob shape
Cockpit control knobs must conform to the general shapes (but not necessarily the exact sizes or specific proportions) in the following figure:
CS 25.783 Fuselage Doors
(See AMC 25.783) (a) General. This paragraph applies to fuselage doors, which includes all doors, hatches, openable windows, access panels, covers, etc.…
CS 25.785 Seats, berths, safety belts and harnesses
(See AMC 25.785) (a) A seat (or berth for a non-ambulant person) must be provided for each occupant who has reached his or her second birthday.
AMC 25.785 Seats, Berths, Safety Belts and Harnesses
CS 25.787 Stowage compartments
(See AMC 25.787) (a) Each compartment for the stowage of cargo, baggage, carry-on articles and equipment (such as life rafts) and any other stowage…
CS 25.788 Passenger amenities
(See AMC 25.788) (a) Showers: If a shower cubicle is installed (See AMC 25.788(a) and AMC 25.1447(c)(3)):
CS 25.789 Retention of items of mass in passenger and crew compartments and galleys
Means must be provided to prevent each item of mass (that is part of the aeroplane type design) in a passenger or crew compartment or galley from…
CS 25.791 Passenger information signs and placards
(See AMC 25.791) (a) If smoking is to be prohibited, there must be at least one placard so stating that is legible to each person seated in the cabin.
CS 25.793 Floor surfaces
(See AMC to CS 25.793 and 25.810(c)) The floor surface of all areas, which are likely to become wet in service, must have slip resistant properties.
CS 25.795 Security considerations
(see AMC 25.795) (a) Protection of flightdeck. If a secure flightdeck door is required by operating rules, the bulkhead, door, and any other accessible…
AMC 25.795 Security considerations
AMC 25.795(a)(1) Flightdeck intrusion resistance
AMC 25.795(a)(2) Flightdeck penetration resistance
AMC 25.795(b)(1) Flight deck smoke protection
AMC 25.795(b)(2) Passenger cabin smoke protection
AMC 25.795(b)(3) Cargo compartment fire suppression
AMC 25.795(c)(1) Least risk bomb location
AMC 25.795(c)(2) Survivability of systems
CS 25.801 Ditching
If certification with ditching provisions is requested, the aeroplane must meet the requirements of this paragraph and CS 25.807(i), 25.1411 and…
CS 25.803 Emergency evacuation
(See AMC 25.803) (a) Each crew and passenger area must have emergency means to allow rapid evacuation in crash landings, with the landing gear extended…
CS 25.807 Emergency exits
(See AMC 25.807) (a) Type. For the purpose of this CS-25, the types of exits are defined as follows:
CS 25.809 Emergency exit arrangement
(See AMC 25.809) (a) (1) Each emergency exit, including a flight crew emergency exit, must be a movable door or hatch in the external walls of the…
AMC 25.809 Emergency exit arrangement
AMC 25.809(a) Emergency exit outside viewing
AMC 25.809(a)(3) Emergency exit arrangement
AMC 25.809(c) and (e) Testing of the opening of passengeroperated exits
CS 25.810 Emergency egress assisting means and escape routes
(See AMC 25.810) (a) Each non-over-wing Type A, Type B or Type C exit, and any other non-over-wing landplane emergency exit more than 1.8 m (6 feet) from…
AMC 25.810 Emergency egress assisting means and escape routes
AMC 25.810(a)(1)(iv) Capability of assisting means in wind conditions
CS 25.811 Emergency exit marking
(See AMC 25.811) (a) Each passenger emergency exit, its means of access, and its means of opening must be conspicuously marked.
AMC 25.811 Emergency exit marking
CS 25.812 Emergency lighting
(See AMC 25.812) (a) An emergency lighting system, independent of the main lighting system, must be installed.
AMC 25.812(b)(1) Emergency lighting
AMC 25.812(b)(2) Emergency lighting
CS 25.813 Emergency exit access and ease of operation
(See AMC 25.813) (a) There must be a passageway leading from the nearest main aisle to each Type A, Type B, Type C, Type I, or Type II emergency exit and…
AMC 25.813 Emergency exit access
CS 25.815 Width of aisle
(See AMC 25.815) The passenger aisle width at any point between seats must equal or exceed the values in the following table:
CS 25.817 Maximum number of seats abreast
On aeroplanes having only one passenger aisle, no more than 3 seats abreast may be placed on each side of the aisle in any one row.
CS 25.819 Lower deck service compartments (including galleys)
(See AMC 25.819) For aeroplanes with a service compartment located below the main deck, which may be occupied during the taxi or flight but not during…
AMC 25.819 Lower deck service compartments (including galleys)
CS 25.820 Lavatory doors
All lavatory doors must be designed to preclude anyone from becoming trapped inside the lavatory.
CS 25.831 Ventilation
(See AMC 25.831) (a) Under normal operating conditions and in the event of any probable failure conditions of any system that would adversely affect the…
CS 25.832 Cabin ozone concentration
The aeroplane cabin ozone concentration during flight must be shown not to exceed – (1) 0·25 parts per million by volume, sea level equivalent, at any…
CS 25.833 Combustion heating systems
Combustion heaters must be approved.
CS 25.841 Pressurised cabins
Pressurised cabins and compartments to be occupied must be equipped to provide a cabin pressure altitude of not more than 2438 m (8000 ft) at the maximum…
CS 25.843 Tests for pressurised cabins
Strength test. The complete pressurised cabin, including doors, windows, and valves, must be tested as a pressure vessel for the pressure differential…
CS 25.851 Fire extinguishers
(See AMC 25.851) (a) Hand fire extinguishers. (See AMC 25.851(a).) (1) The following minimum number of hand fire extinguishers must be conveniently…
AMC 25.851(a) Hand fire extinguishers
AMC 25.851(a)(1) Hand fire extinguishers
AMC 25.851(a)(2) Hand fire extinguishers
AMC 25.851(b) Built-in Fire Extinguishers for Cargo Compartments
Appendix 1 Analytical methods for determining Halon 1301 concentration levels
PURPOSE. This appendix contains analytical methods for determining Halon 1301 fire extinguishing agent concentration levels in empty or loaded cargo…
CS 25.853 Compartment interiors
(See AMC 25.853) For each compartment occupied by the crew or passengers, the following apply:
CS 25.854 Lavatory fire protection
(See AMC 25.854) For aeroplanes with a passenger capacity of 20 or more, or with a cabin length of 18.29 m (60 ft) or more:
CS 25.855 Cargo or baggage compartments
(See AMC 25.855 and 25.857) For each cargo or baggage compartment, the following apply:
CS 25.856 Thermal/acoustic insulation materials
(See AMC 25.856(a)) (a) Thermal/acoustic insulation material installed in the fuselage must meet the flame propagation test requirements of Part VI of…
AMC 25.856(a) Thermal/acoustic insulation materials: Flame propagation resistance
AMC 25.856(b) Thermal/acoustic insulation materials: Flame penetration (Burnthrough) resistance
CS 25.857 Cargo compartment classification
(See AMC 25.855 and 25.857) (a) Class A. A Class A cargo or baggage compartment is one in which – (1) The presence of a fire would be easily discovered…
CS 25.858 Cargo or baggage compartment smoke or fire detection systems
If certification with cargo or baggage compartment smoke or fire detection provisions is requested, the following must be met for each cargo or baggage…
CS 25.859 Combustion heater fire protection
Combustion heater fire zones. The following combustion heater fire zones must be protected from fire in accordance with the applicable provisions of CS…
CS 25.863 Flammable fluid fire protection
(See AMC 25.863) (a) In each area where flammable fluids or vapours might escape by leakage of a fluid system, there must be means to minimise the…
CS 25.865 Fire protection of flight controls, engine mounts, and other flight structure
Essential flight controls, engine mounts, and other flight structures located in designated fire zones or in adjacent areas which would be subjected to…
CS 25.867 Fire protection: other components
Surfaces to the rear of the nacelles, within one nacelle diameter of the nacelle centreline, must be constructed of materials at least equivalent in…
CS 25.869 Fire protection: systems
(See AMC 25.869) (a) Electrical system components: Components of the electrical system must meet the applicable fire and smoke protection requirements of…
AMC 25.869(a)(1) Electrical System Fire and Smoke Protection
CS 25.871 Levelling means
There must be means for determining when the aeroplane is in a level position on the ground.
CS 25.875 Reinforcement near propellers
Each part of the aeroplane near the propeller tips must be strong and stiff enough to withstand the effects of the induced vibration and of ice thrown…
CS 25.899 Electrical bonding and protection against static electricity
(See AMC 25.899) (a) Electrical bonding and protection against static electricity must be designed to minimise accumulation of electrostatic charge…
AMC 25.899 Electrical bonding and protection against static electricity
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