• Flat Surface 35" Headstrike Arc Seat Reference Point Headstrike Envelope Figure 3 13
10. FLIGHT ATTENDANT DIRECT VIEW.
a. As defined earlier in this AC, flight attendant direct view pertains to direct visual contact between the flight attendant and the passenger cabin. The regulation requires direct view for all flight attendant seats, unless proximity to floor level exits would be compromised. While the regulation gives proximity to floor level exits higher priority, every effort should be made to accommodate both requirements. It is possible though, that not all flight attendants will have a direct view of the cabin. It is the intention of the requirements, however, that no less than a majority of the required flight attendants contribute to direct view, even considering that some seat locations may be dictated by proximity to floor level exits. These flight attendants need not share equally in direct view, however, a majority of the required flight attendants should contribute to paragraph 10a(3) below. In the case where there are only two required flight attendants, it is acceptable that proximity to floor level exits dictates the location of one of the seats, if the criteria below can be satisfied by one flight attendant. The following should be visible to flight attendants:
(1) The length of each main aisle adjacent to all passenger seats,
(2) Each floor level exit,
(3) Using the criteria in Appendix A, at least 50 percent (i.e., with zero head movement) of the total number of passenger seats in the cabin, and
(4) Using the criteria in Appendix A, at least 25 percent (i.e., with zero head movement) of the passenger seats in each visually divided zone.
(5) For non-floor level exits not equipped with flightdeck annunciation of the open condition, the seat adjacent to each such exit.
(6) The criteria in paragraphs 10a(1), (2), and (5) should be satisfied with flight attendants seated with restraint systems fastened, as would be the case for takeoff and landing. No lateral movement or head rotation should be utilized to meet the above criteria. Peripheral vision is assumed to be 180 degrees as referenced in Society of Automotive Engineering (SAE) J985.
(7) The criteria of paragraphs 10a(3) and (4) may be satisfied using the figures in Appendix A and applying the guidance noted.
b. The following guidance can be used to determine whether aisles, exits or seats are within direct view:
(1) An aisle is considered to be in direct view if, from a flight attendant seat, any part of a standing person is visible at each point in the minimum required aisle.
(2) A floor level exit is considered to be in direct view if the exit itself is directly visible, or if a person approaching the exit or entering the passageway to the exit is visible from a flight attendant seat.
(3) A seat is considered to be in direct view if any portion of the vertically projected plan view of the seat (up to a height of 5 feet above the floor) is within the line of sight of a flight attendant, seating as noted in paragraph 10c below. Alternatively:
(a) A person seated in the seat is visible when they raise their arm over their head, or
(b) A five foot high pole may be placed in front of the seat; if the pole is visible, the seat is considered to be in direct view.
NOTE: Assessments of seats are made assuming an unoccupied airplane.
c. Persons used to determine acceptability of the arrangement should be 5th percentile females and also, in the case of flight attendants, 95th percentile males (where such evaluation could produce more critical results). For the purpose of establishing sight lines, heights above the seat pan representing the seated height of a 5th percentile female and 95th percentile male, may be established using a current, recognized source. See paragraph 5d for anthropometric reference source.
d. Acceptability of the arrangement should be determined under the minimum lighting levels to be allowed for takeoff and landing.
e. Cabin features, such as movable panels in partitions, should be in the taxi, takeoff and landing position.
NOTE: The airframe manufacturer should identify on the type design the flight
attendant seats that are required to comply with the direct view requirements,
and that therefore need to be occupied in service, and provide this information
to the operator.
Ali Bahrami Manager, Transport Airplane Directorate Aircraft Certification Service 15
100 90 80 ~ 70
• .:
,! 60 .:,
• • Ill ---- Total Cabin\llewvs . Head Movement ... 50
• - cabin Zone vi ewvs. Head Movement
• .. : 40
• • ~
• ~ 30 20 10 2 4 6 10 12 14 16 L3 t er a, I He a d M ov ement in In c he s 05/11/10 AC 25.785-1B Appendix A Appendix A Direct View Determination for Visually Divided Zones and Airplane Cabins In order to permit a more performance based assessment, the following relationship of direct view and flight attendant head movement has been constructed. Figure A-1 shows an envelope of cabin view as a function of the amount of head movement utilized. The curves depicted are based on previously accepted methods of compliance.
Cabin Zone Acceptance: For each zone in the cabin, any combination of latera l head movement and percentage of seats in view that is above the lower curve is considered acceptable. The airplane cabin zone direct view may be established using head movement as necessary at each fight attendant seat to achieve the total percentage, provided such movement is permitted by the restraint system when fastened.
Figure A-1 NOTE: Measured head movement is from common reference point, such as the eye reference point of the normally seated occupant.
Total Cabin Acceptance: The simplest method to determine total cabin view is to utilize the same amount of head movement at each flight attendant position and determine the total number of seats in view, based on the curves. In this case, the zonal criteria and the total airplane criteria may be treated independently. The airplane satisfies the criteria as long as the total number of seats in view is above the “total cabin” curve at some point (i.e., using the same amount of head movement at each flight attendant seat). The total cabin view should be established in 5 percent increments (rounded up), since the curves are not refined enough to be more precise. An A-1
I 10 ++---------------------------- --;
0+---~---~---~---~--~---~---~-------4 0 2 4 6 8 10 12 16 Lateral Head Mo vement in Inche s ---- Tot al Cabin View vs. Head M ovement Cm in Zone view vs. Head M ovement 05/11/10 AC 25.785-1B Appendix A applicant may simply choose to select a fixed amount of head movement and assess the total cabin view at that point. Alte rnatively, the curves as shown in Figure A-2 may be developed and the point on the curve where maximum cabin viewing occurs may be established. As noted above, each zone may be assessed to determine its maximum direct view even if the assessment criteria are different among the specific zones (different amount of head movement at each flight attendant seat).
The following example illustrates one way to do this.
Example: An airplane with three divided zones, with a total passenger capacity of 375, and zone capacities of 50, 175 and 150. Five f light attendants (out of a required 8) participate in direct view as follows: Flight attendants 1 and 2 view zone 1, flight attendants 3 and 4 view zone 2 and flight attendant 5 views zone 3.
Each flight attendant’s actual direct view coverage as a function of head movement is shown on Figure A-2 (note that the movement is limited by the restraint system):
Figure A-2 In Figure A-2, flight attendants 1,3 and 5 have direct view that is unaffected by head movement.
Flight attendants 2 & 4 can improve their view with a limited amount of head movement, although for flight attendant 4 the view diminishes beyond a certain point. The overall assessment of acceptability can be made as follows:
A-2
Appendix A
a. All flight attendants have adequate zone viewing since each line is above the zone viewing curve at some point.
Peak zone viewing is as follows:
Flight attendant 1 ~40 percent of zone 1 or 20 seats.
Flight attendant 2 ~58 percent of zone 1 or 29 seats.
Flight attendant 3 ~81 percent of zone 2 or 142 seats.
Flight attendant 4 ~72 percent of zone 2 or 126 seats.
Flight attendant 5 ~81 percent of zone 3 or 121 seats.
b. The total cabin viewing can be established by a point on the zone curve at which the sum of the individual zone views exceeds the total cabin view curve, for a given amount of head movement. For this example arrangement, a large portion of the cabin is visible at 4” of head movement. With 4” of head movement, the corresponding total cabin view is read at ~70 percent. As long as a total of 70 percent of the cabin is in direct view of the combined 5 flight attendants using no more than 4” head movement, the arrangement is acceptable. For this arrangement, that would be 263 seats.
c. For this airplane, total coverage is no worse than the sum of the maximum zone coverages, or 29??+142+121 or 292 seats, so the arrangement satisfies the criteria.
d. Figure A-3 illustrates the amount of viewing coverage provided in each zone by each flight attendant seat position (note that the figure is representative only, and cannot be used to estimate, or extrapolate direct view). As can be seen, there is some degree of redundancy in the zone viewing among flight attendants, but in this case no flight attendant’s view is completely redundant with any other. In actuality, the total cabin direct view is greater than shown above since zones 1 and 2 are viewed by more than one flight attendant.
F/Α 2 175 Pax F/Α 4 Seats Zone 2Zone 1 Zone 3 F/Α 3 150 Pax F/Α 1 50 Pax Seats Seats F/Α 5 Figure A-3 A-3