AC 25-17A

Advisory circular · Transport Airplane Cabin Interiors Crashworthiness Handbook

Approved
May 18, 2009
Last reviewed
June 27, 2016
Cancels
AC25-17
Family
AC 25-17 · 2 versions
Revision
A
14 CFR parts
25
Cited by
1 AD

Guidance, not mandatory unless a rule or AD requires it. DRS record last changed October 23, 2026.

Show pages 470–481
Page 482Open in PDF

466 (B) If the device is intended for use during TT&L, and it has a constant tension cord, then no cord length and no cord loop evaluations are required.

(C) If the device is intended for use during TT&L, and it does not have a constant tension cord and it is not installed on an aisle, cross aisle or exit row, then no cord loop and length evaluation is required.

(D) If, however, the device is intended for use during TT&L, and does not have a constant tension cord, and is installed on an aisle armrest, a cross aisle armrest or aisle side seatback or in an exit row, then cord loop and length evaluations must be made to ensure that the corded device will not interfere with passenger emergency egress. These devices may include breakaway capabilities in the cord connections, or frangibility in the cord itself, that can act as compensating features during the evaluation.

(1) Cord Loop Evaluation. Loops created by mis-stowage of a corded device should be evaluated to determine if they pose an egress hazard. It should be shown that, with the handset stowed in its cradle, an unstowed cord does not become a hazard which can entrap or snag limbs or clothing during an emergency evacuation. Evaluations should be made with a 5th percentile female and a 95th percentile male, as follows:

(i) Any cord loop that can be formed by mis-stowing the handset using reasonable force should be evaluated to determine that the location of the loop does not pose an egress hazard. Loops formed below the level of the armrest and contained within the bounds of the seat bottom cushion should be acceptable.

(ii) Any loop that can be formed by mis-stowing the handset using reasonable force, which extends into an aisle, must be unable to encircle an appendage (limb or clothing) without significant manipulation or contrivance.

(iii) Any loop that can be formed by mis-stowing the handset using reasonable force, in a location where a limb may be encircled, must be easily escapable by normal passenger movement, or the handset must be able to be pulled free with normal motion and strength.

(2) Cord Length. Applicants must demonstrate that their handset installation cord length will not permit the handset to lie flat on the floor when the handset is not properly stowed. Also, on seat back mounted handsets, the cord length must be restricted so that the device cannot be used by anyone seated across the aisle or by anyone seated in a row behind the row directly facing the unit. Note: This does not preclude the passing of the handset forward to the row on which the handset is mounted.

(E) Associated Placards: If placards are installed which state when a handset may (or may not) be used, at least one placard should be in plain sight of the occupant of any position from which the handset is likely to be used, whether or not the handset is stowed.

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467 These, and any other safety related placards, should be of sufficient size and color contrast (lettering to background) so as to be easily visible to all expected users under normal cabin lighting conditions. Visibility during low light level conditions, which are often encountered during night flights, is desirable, but not mandatory.

(iv) Finally, this guidance material covers compliance for cabin safety issues only.

All other applicable certification regulations still apply.

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FIGURE 419-1 CORDED DEVICES Yes Corded Device No intended for use during TT&L Constant Tension No Located in air Exit Row or Aisle* or No Cord Cross Aisle Yes Yes Cord Creates Redesign Loop Impeding Evac Yes No Cord Length Redesign Creates a Barrier to Evac Yes Redesign No Head Strike Yes Located in the Found Acceptable Head Strike Zone Yes No Corded Device meets Cabin → Safety Requirements for * Aisle location - mounted on either the seatback or the armrest Installation ** ** This process only covers compliance for Cabin Safety regulations, all other applicable regulations still apply.

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(8) Paragraph (b). When it is required that there be an area adjacent to an exit to permit a crewmember to assist passengers in the use of escape devices, a 12 x 20-inch assist space with the long dimension parallel to and clear of the required 20-inch exit approach passageway or equivalent facility should be provided. The area should be adequate to permit an attendant to stand erect and to perform needed assist services in the evacuation of passengers. Minor deviations from the 12 X 20-inch assist space are permitted if an evaluation is made that the effectiveness of the exit is not reduced. A demonstration may be necessary to show that passengers can be effectively evacuated. (Amendment 25-0)

(9) Paragraph (b). Seat breakover should not be used to clear the assist space. Recline into the assist space and cushion compression are permitted, if the seat is easily pushed forward, and the cushion readily compressible. (Amendment 25-0)

(10) Paragraph (b). If the assist space is under the overhead bins such that the attendant cannot stand erect, additional space, such as removal of the outboard seat, is required. The effectiveness of the assist space must be demonstrated. (Amendment 25-0)

(11) Paragraph (b). The assist space need not be directly adjacent to the exit. In some cases the assist space could be inboard a short distance from the exit but outboard of the main aisle. (Amendment 25-0)

(12) Paragraph (b). Assist handles are often provided at floor level emergency exits to provide stability for the flight attendant during an emergency evacuation. There is no specific requirement to provide an assist handle however, where an assist handle has been utilized for an evacuation demonstration used to show compliance with the regulations, production airplanes should also have an assist handle. The assist handle should be located at the assist space, even if the location of the assist space is not the same as the location on the airplane used for the evacuation demonstration. (Amendment 25-0)

(13) Paragraph (c)(2)(i). For airplanes with 20 or more passenger seats the following guidance applies.

(i) An armrest should not protrude into the projected opening of the required exit, even if it could be rotated out of the projected exit opening. (Amendment 25-0)

(ii) Armrests, curtains, or other protuberances which are removed simultaneously with opening of the exit are not considered to obstruct the projected opening provided.

(Amendment 25-32)

(iii) Berth installations, whether or not made up, should not obstruct the projected opening of the exit provided for a distance from that exit not less than the width of the narrowest passenger seat installed on the airplane. (Amendment 25-0)

(iv) Seat back recline or breakover should not render the exit unopenable from either inside or outside. (Amendment 25-0)

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(v) Seat back breakover and recline at the outboard seat locations should have a positive lockout, (e.g., such that a tool is required to adjust the breakover or recline) to prevent the seatback from protruding into the projected opening of the exit provided. Special seat identification is required. The projected exit opening provided must be not be obstructed rather than the minimum required opening must be not be obstructed. (Amendment 25-32)

(vi) All portions of the outboard seat should clear the projected exit opening. No seat cushion compression should be allowed in order to clear the projected exit opening provided. Since seats are not directly controllable by the crew and are susceptible to passengers’ actions after the crew has completed their preparatory duties, crew procedures or placards are not considered adequate to maintain the proper access to the exit. (Amendment 25-32)

(vii) Interior features (galleys, closets, seats, etc.) must not prevent an exit from being opened. (Amendment 25-32)

(viii) The outboard seats, berths, or other protrusions, even though they clear the projected exit opening, should not interfere with the opening of the exit. For example, interior lining or trim on the exit hatch may extend beyond the projected opening of the exit, and could interfere with opening of the exit by contacting seats or other structure. (Amendment 25-46)

(14) Paragraph (c)(2)(ii). For airplanes with 19 or less passenger seats the following guidance applies. The region that is discussed in this paragraph is the same region that is defined in paragraph (c)(2)(i) of the regulation.

(i) An armrest should not protrude into the projected opening of the required exit, even if it could be rotated out of the projected exit opening. (Amendment 25-0)

(ii) Armrests, curtains, or other protuberances which are removed simultaneously with opening of the exit are not considered to restrict the required minimum opening.

(Amendment 25-0)

(iii) Projection of the seat backs into the minimum required exit opening should be permitted only if the seat back can be pushed forward or aft to clear the opening with the seat occupied. The force required to push the seat back away from the opening should be as low as practicable and should not exceed a maximum of 35 lbs with the seat unoccupied. The action should not require operation of any mechanical release. (Refer to paragraph 81b(8) for minimum breakover force.) A clear opening should permit the required minimum exit shape to be projected inward past the seat bottom and back cushion. Minor protrusion of the seat upholstery is acceptable if it does not interfere with exit removal and if it could be compressed without special effort by the person(s) using the exit. (Amendment 25-0)

(iv) Berth installations, whether or not made up, should not decrease the accessibility and utility of emergency exits. (Amendment 25-0)

(v) Seat back recline or breakover should not render the exit unopenable from either inside or outside. (Amendment 25-0)

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(vi) A minor protrusion, not to exceed two-inches, of the outboard seat cushion into the required exit opening is permitted, if the cushion is easily compressed. A force of 170 lbs distributed over 40 square-inches has been found acceptable to determine if the cushion is easily compressed. (Amendment 25-0)

(vii) For the smaller airplanes there could be some minor obstructions, provided that they do not reduce the effectiveness of the exit. Unattached (loose), soft seat-back cushions on side-facing divans, for example, may encroach into the minimum required exit opening provided the cushion can be readily moved away and the exit easily opened from the inside and outside. Other incursions into the projected opening, and even some interference in opening the exit are acceptable for these smaller airplanes, provided the exit maintains its effectiveness, and remains openable. The exit signs may not be obscured. (Amendment 25-32)

(viii) Interior features (galleys, closets, seats, etc.) must not prevent an exit from being opened from either inside or outside. (Amendment 25-32)

(15) Paragraphs (c)(2)(i) and (c)(2)(ii). The wording “a passenger seating configuration, excluding pilot seats,” which was promulgated with the intent of being consistent with Amendment 23-10 to part 23, does not directly address seats intended for use by observers or flight attendants. Seats approved for use by observers or flight attendants are not included in the passenger seating configuration. Seats that have dual approval for occupancy by either crew/observers or passengers will be included in the passenger seating configuration.

(Amendment 25-32)

(16) Paragraph (d). The curtains may protrude slightly into the required passageway, provided the curtain and its tie-backs do no inhibit passage. (Amendment 25-1)

(17) Paragraph (e). Arrangements have been found acceptable for a lavatory door where the lavatory would be occupied by one passenger during taxi, takeoff, and landing. This arrangement would require an equivalent level of safety finding. The door should be secured open for taxi, takeoff, and landing and be provided with an emergency egress panel. An emergency egress panel is a panel that can be broken through by a passenger who may be inadvertently trapped behind the door. A demonstration should be done using a 5th percentile female subject (approximately 60-inches tall and weighing 102 lbs). (Amendment 25-1)

(18) Paragraph (e). Curtains within a sliding frame are not considered to be a door if a person can easily pass through the curtain when closed. The curtain should be fastened open for taxi, takeoff, and landing. (Refer to paragraph 1041b(7).) (Amendment 25-1)

(19) Paragraph (e). Doors are permitted on galleys, etc. that are between the main aisle and exit if the door is not between passenger compartments. This would also apply to rooms not occupied for taxi, takeoff, and landing. Doors that open into a main aisle should not be permitted

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472 in passenger compartments occupiable for taxi, takeoff or landing or in passenger compartments with passenger emergency exits. These types of compartments are typically found in "executive" interiors with the main aisle along the side wall. (Amendment 25-1) 420 - 440. [RESERVED]

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473 SECTION 25.815 WIDTH OF MAIN AISLE

441. REGULATION IN EFFECT AT ADOPTION OF PART 25.

a. Regulation.

The main passenger aisle width at any point between seats must equal or exceed the values in the following table:

Minimum main passenger aisle width Passenger seating capacity Less than 25-inches from floor 25-inches and more from floor

10 or less ...................... 12-inches 18-inches 11 through 19 ............... 12-inches 20-inches 20 or more ..................... 15-inches 20-inches

b. Guidance.

(l) The passenger aisle width is the normal distance between opposite seats measured without occupants. The distance should be determined without compression of seat fabric or cushion and with the seats or other aisle constraints in the most adverse position, such as seats reclined or broken over. Unlike typical commercial aircraft, private use airplanes (i.e., not for hire, not for common carriage) have seats that can be moved during flight operations. The seating can be reconfigured to accommodate meetings and other arrangements. Some of these arrangements can reduce the aisle widths below those specified. This is acceptable only during en-route flight and only if clear instructions are provided requiring that the seats be positioned for taxi, takeoff, and landing in an arrangement that meets the required aisle widths. The private use provision does not preclude the operator from receiving remuneration to the extent consistent with 14 CFR parts 125 and 91, subpart F, as applicable. (Amendment 25-0)

(2) When the measurement is not between seats but between other aisle constraints such as galleys, coat closets, storage compartments, etc., the minimum widths at the specified vertical distance above the floor still prevails. Protuberances such as door knobs, latches, rails, etc., should be considered if they encroach into the specified aisle width. This measurement should be made using the vertical projection of any protuberance in its appropriate height zone (less than 25-inches from the floor or 25-inches and more from the floor). The effect of the protuberance on the evacuation of the airplane should be considered when determining if it may or may not protrude into the required aisle width. Curtains may protrude slightly into the required aisle, provided the curtain and its tie-back do not inhibit passage. (Amendment 25-0)

(3) For staggered seat rows, or zigzag aisles, the aisle width distance may be considered as that measured perpendicular to the aisle pathway at any point along its full path. (Amendment 25-0)

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(4) Arm rests that swing up, such as those for handicapped persons, may encroach upon the 20-inch width in the up position. If so, the arm rest should automatically return to the down position or be appropriately placarded. (Amendment 25-0)

(5) The main aisle widths, as defined by the regulation, should be maintained from floor level to a height of at least 73-inches above the floor (top of the floor covering). For airplanes that do not have 73-inches between the floor and the ceiling panels, the aisle width should be maintained from the floor to the height of the ceiling panels. Any features that hang (signs, video monitors etc.) from the ceiling or span across main aisle (i.e., class dividers and curtain headers) should be at least 73-inches above the floor, unless they are retractable and are placarded to be retracted for taxi, takeoff, and landing (TT&L). For airplanes that do not have 73-inches between the floor and the ceiling panels any features that hang (signs, video monitors etc.) from the ceiling should not be positioned in the main aisle. Alternate locations should be used, e.g., over seat, on the side wall etc. These features should also be appropriately padded or rounded to preclude injury when persons are moving about the cabin. (Amendment 25-0)

442. AMENDMENT 25-15, Effective October 24, 1967.

a. Regulation.

[ The passenger aisle width at any point between seats must equal or exceed the values in the following table:] Minimum main passenger aisle width (inches) Passenger seating capacity Less than 25-inches from floor 25-inches and more from floor

10 or less ..................... 12-inches [15-inches] 11 through 19 .............. 12-inches 20-inches 20 or more ................... 15-inches 20-inches

b. Guidance.

(l) The passenger aisle width is the normal distance between opposite seats measured without occupants. The distance should be determined without compression of seat fabric or cushion and with the seats or other aisle constraints in the most adverse position, such as seats reclined or broken over. Unlike typical commercial aircraft, private use airplanes (i.e., not for hire, not for common carriage) have seats that can be moved during flight operations. The seating can be reconfigured to accommodate meetings and other arrangements. Some of these arrangements can reduce the aisle widths below those specified. This is acceptable only during en-route flight and only if clear instructions are provided requiring that the seats be positioned for taxi, takeoff, and landing in an arrangement that meets the required aisle widths. The private use provision does not preclude the operator from receiving remuneration to the extent consistent with 14 CFR parts 125 and 91, subpart F, as applicable. (Amendment 25-0)

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(2) When the measurement is not between seats but between other aisle constraints such as galleys, coat closets, storage compartments, etc., the minimum widths at the specified vertical distance above the floor still prevails. Protuberances such as door knobs, latches, rails, etc., should be considered if they encroach into the specified aisle width. This measurement should be made using the vertical projection of any protuberance in its appropriate height zone (less than 25-inches from the floor or 25-inches and more from the floor). The effect of the protuberance on the evacuation of the airplane should be considered when determining if it may or may not protrude into the required aisle width. Curtains may protrude slightly into the required aisle, provided the curtain and its tie-back do not inhibit passage. (Amendment 25-0)

(3) For staggered seat rows, or zigzag aisles, the aisle width distance may be considered as that measured perpendicular to the aisle pathway at any point along its full path. (Amendment 25-0)

(4) Arm rests that swing up, such as those for handicapped persons, may encroach upon the 20-inch width in the up position. If so, the arm rest should automatically return to the down position or be appropriately placarded. (Amendment 25-0)

(5) The main aisle widths, as defined by the regulation, should be maintained from floor level to a height of at least 73-inches above the floor (top of the floor covering). For airplanes that do not have 73-inches between the floor and the ceiling panels, the aisle width should be maintained from the floor to the height of the ceiling panels. Any features that hang (signs, video monitors etc.) from the ceiling or span across main aisle (i.e., class dividers and curtain headers) should be at least 73-inches above the floor, unless they are retractable and are placarded to be retracted for taxi, takeoff, and landing (TT&L). For airplanes that do not have 73-inches between the floor and the ceiling panels any features that hang (signs, video monitors etc.) from the ceiling should not be positioned in the main aisle. Alternate locations should be used, e.g., over seat, on the side wall etc. These features should also be appropriately padded or rounded to preclude injury when persons are moving about the cabin. (Amendment 25-0)

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443. AMENDMENT 25-38, Effective February 1, 1977.

a. Regulation.

The passenger aisle width at any point between seats must equal or exceed the values in the following table:

Minimum main passenger aisle width (inches) Passenger seating capacity Less than 25-inches from floor 25-inches and more from floor

10 or less ..................... 1 12-inches 15-inches 11 through 19 .............. 12-inches 20-inches 20 or more ................... 15-inches 20-inches

[ 1 A narrower width not less than nine-inches may be approved when substantiated by tests found necessary by the Administrator.]

b. Guidance.

(1) The above-defined minimum aisle widths consider the adverse effects of possible post-crash seat deflections. The maximum allowed post-crash seat deflections for both § 25.561 and § 25.562 assumed these pre-crash aisle widths. Consequently, any tests that are proposed to substantiate the acceptability of an aisle width that is less than twelve-inches on airplanes seating ten or less, as allowed above, need to address the additional aisle width reduction due to worstcase post-crash seat deflections of § 25.561 and when applicable § 25.562. (Amendment 25-38)

(2) Part 382 was amended by Amendment 382-3, Nondiscrimination on the Basis of Handicap in Air Travel, effective April 5, 1990, and implements the Air Carrier Access Act of 1986. One effect of this amendment was to require certain operators of certain airplanes to provide within a certain timeframe movable aisle armrests on at least half of passenger aisle seats. The intent of this amendment, was to increase accessibility for handicapped passengers.

Airplane interiors that are configured to comply with part 382 requirements may have from onehalf to all of the aisle passenger seats equipped with movable armrests. Armrests may move in such a manner as to decrease the available aisle width, and should therefore be assessed with those requirements in mind. (Amendment 25-38)

(3) The following design options could be considered acceptable means for satisfying the part 25 concerns due to part 382 implementation: (Amendment 25-38)

(i) If the movement of the armrest were not into the required aisle space, there would be no compliance problem. (Amendment 25-38)

(ii) If the armrest were to return to the down position, unless held upward by a person, the impact on evacuation would be negligible. (Amendment 25-38)

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(iii) The armrest could be removable (provided it was positively latched when installed). (Amendment 25-38)

(iv) If the hinged armrest was normally fastened down, but had a discreetly located release that a flight attendant could operate in the event there was a need to accommodate a disabled passenger, the installation may be acceptable. (Amendment 25-38)

(4) The passenger aisle width is the normal distance between opposite seats measured without occupants. The distance should be determined without compression of seat fabric or cushion and with the seats or other aisle constraints in the most adverse position, such as seats reclined or broken over. Unlike typical commercial aircraft, private use airplanes (i.e., not for hire, not for common carriage) have seats that can be moved during flight operations. The seating can be reconfigured to accommodate meetings and other arrangements. Some of these arrangements can reduce the aisle widths below those specified. This is acceptable only during en-route flight and only if clear instructions are provided requiring that the seats be positioned for taxi, takeoff, and landing in an arrangement that meets the required aisle widths. The private use provision does not preclude the operator from receiving remuneration to the extent consistent with 14 CFR parts 125 and 91, subpart F, as applicable. (Amendment 25-0)

(5) When the measurement is not between seats but between other aisle constraints such as galleys, coat closets, storage compartments, etc., the minimum widths at the specified vertical distance above the floor still prevails. Protuberances such as door knobs, latches, rails, etc., should be considered if they encroach into the specified aisle width. This measurement should be made using the vertical projection of any protuberance in its appropriate height zone (less than 25-inches from the floor or 25-inches and more from the floor). The effect of the protuberance on the evacuation of the airplane should be considered when determining if it may or may not protrude into the required aisle width. Curtains may protrude slightly into the required aisle, provided the curtain and its tie-back do not inhibit passage. (Amendment 25-0)

(6) For staggered seat rows, or zigzag aisles, the aisle width distance may be considered as that measured perpendicular to the aisle pathway at any point along its full path. (Amendment 25-0)

(7) Arm rests that swing up, such as those for handicapped persons, may encroach upon the 20-inch width in the up position. If so, the arm rest should automatically return to the down position or be appropriately placarded. (Amendment 25-0)

(8) The main aisle widths, as defined by the regulation, should be maintained from floor level to a height of at least 73-inches above the floor (top of the floor covering). For airplanes that do not have 73-inches between the floor and the ceiling panels, the aisle width should be maintained from the floor to the height of the ceiling panels. Any features that hang (signs, video monitors etc.) from the ceiling or span across main aisle (i.e., class dividers and curtain headers) should be at least 73-inches above the floor, unless they are retractable and are placarded to be retracted for taxi, takeoff, and landing (TT&L). For airplanes that do not have 73-inches between the floor and the ceiling panels any features that hang (signs, video monitors