UNITED STATES OF AMERICA 

DEPARTMENT OF TRANSPORTATION 

FEDERAL AVIATION ADMINISTRATION 

RENTON, WASHINGTON 98057-3356 

In the matter of the petition of 

ST Aerospace Mobile, Inc 

Exemption No.11060 

for an exemption from§§ 25.7850), 

25.807(g)(l), 25.807(i)(l), 25.810(a)(l), 

25.812(e), 25.813(b)(l), 25.813(b)(6), 

25.1445(a)(2), and 25.1447(c)(l) ofTitle 

14, Code of Federal Regulations 

Regulatory Docket No. FAA-2014-0351 

PARTIAL GRANT OF EXEMPTION 

By letter dated May 9, 2014, Mr. Kumaresan Subramaniam, Engineering Director, ST Aerospace 

Mobile, Inc., 2100 9th Street, Brookley Complex, Mobile, Alabama, 36615, petitioned the 

Federal Aviation Administration (FAA) for exemption from the requirements of§§ 25. 785G), 

25.807(g)(l) and (i)(l), 25.812(e), 25.813(b)(l) and (6), 25.1445(a)(2), and 25.1447(c)(l) of 

Title 14, Code of Federal Regulations (14 CFR). It was confirmed via telephone conversation on 

August 15,2014, that the petitioner also intended to request relief from the requirements of 

§ 25.810(a)(l). The requested exemption, if granted, would permit relief from the requirements 

of these regulations to allow carriage ofnon-crewmembers (commonly referred to as 

supernumeraries) within the flight deck area on Boeing Model 757-200 airplanes which have 

been converted from a passenger to freighter configuration. 

The petitioner requests relief from the following regulations: 

Section 25.7850), at Amendment 25-88, requires, in pertinent part, handholds to enable 

passengers to steady themselves when moving about the cabin, in the event the airplane 

encounters moderately rough air. 

Section 25.807(g)(l), at Amendment 25-114, requires that, if overwing exits are not 

provided, airplanes having a passenger seating configuration of 1 to 9 seats must be fitted 

with an emergency exit having at least the dimensions of a Type III exit in each side of 

the fuselage. 

Section 25.807(i)(l), at Amendment 25-114, requires that airplanes having a passenger 

seating configuration of nine or fewer seats, excluding pilot seats, must have at least one 

exit above the waterline in each side of the airplane, meeting at least the dimensions of a 

Type IV exit. 
Section 25.81 0( a)(1 ), at Amendment 25-114, requires, in pertinent part, that each nonoverwing emergency exit more than 6 feet from the ground have an approved means to 

assist occupants in descending to the ground. For passenger exits, this must be a selfsupporting, automatically deployed and erected slide at each applicable exit. 

Section 25.812(e), at Amendment 25-128, requires, in pertinent part, that floor 

proxiruity emergency escape-path markings must provide emergency evacuation 

guidance for passengers when all sources of illumination more than 4 feet above the 

cabin aisle floor are totally obscured. 

Section 25.813(b )(1 ), at Amendment 25-128, requires, in pertinent part, that each 

passenger emergency floor-level exit, equipped with an assist means, have an assist space 

next to that exit. 

Section 25.813(b )( 6), at Amendment 25-128, requires a handle at each assist space to 

enable crewmembers to steady themselves when assisting in an evacuation. 

Section 25.1445(a)(2), at Amendment 25-00, requires that when crew and passengers 

share a common oxygen supply source, the distribution system must have a means to 

separately reserve the minimum supply required by the flightcrew on duty. 

Section 25.1447(c)(1), at Amendment 25-116, requires, in pertinent part, that oxygen 

dispensing units must be automatically presented to the occupants before the cabin 

altitude exceeds 15,000 feet. The total number of dispensing units and outlets must 

exceed the number of seats by at least 10 percent. The extra units must be uniformly 

distributed throughout the cabin as practicable, and there must be two oxygen masks in 

each lavatory. 

Related sections of 14 CFR 

Section 121.583(a) contains, in pertinent part, a listing of categories of persons who may 

be carried aboard an airplane in part 121 service, without having to comply with all of the 

requirements of part 121 pertaining to carriage of passengers. 

Section 121.54 7 contains, in pertinent part, a listing of categories of persons who may be 

admitted to the flight deck during operation. 

The petitioner supports its request with the following information: 

This section quotes the relevant information from the petitioner's request, with minor edits for 

clarity. The complete petition is available at the Department of Transportation's Federal Docket 

Management System, on the Internet at http://regulations.gov, in Docket No. FAA-2014-0351. 

ST Aerospace Mobile (STA Mobile) is the applicant for a multiple airplane Supplemental 

Type Certificate for conversion of Boeing 757-200 passenger airplanes to a 15-Unit Load 

Device (ULD) position (15-P) freighter configuration under FAA Project Number 

ST14446AT-T. STA Mobile expects issuance ofSTC by October 15,2014. 

The purpose of this letter is to petition for an exemption from the requirements of certain 

sections of Title 14, Code of Federal Regulations (14 CFR), Part 25, to allow carriage of 

non-crewmembers, or 'supernumerary' personnel, in a compartment within the 

reconfigured flight deck on the converted airplanes. Supernumeraries will be restricted to 

those persons complying with§ 121.583 (a)(l) through (a)(8). 

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STA Mobile requests that the publication and comment procedures be waived in 

accordance with § 11.29 and § 11.87 for the following reasons: 

i. Similar exemptions have been issued by the FAA for STC ST03562AT (STA Mobile 

757-200SF), Boeing 757-200PF & STC ST01529SE (Precision Conversions' 757-

200PCF) 

ii. Granting this petition would not set a precedent 

DESCRIPTION OF CONVERSION 

The main features of the intended conversion from the passenger aircraft configuration 

include: 

a) Installation of a side-opening main deck cargo door (MDCD) and its surround 

structure. The MDCD design is based on that used in the STA Mobile 757-200 

Combi Freighter (STC ST03952AT) construction. 

b) Installation of a 9g rigid cargo barrier (RCB) at approximately STA 335, identical 

to that in the Boeing 757-200PF "package freighter ('PF')" design, providing 

separation between the flight deck and the main deck cargo compartment. 

c) Installation of a vendor-developed main deck cargo loading system (CLS) to 

accommodate 15 industry-standard 88 x 125 contoured ULDs, such as the 

International Air Transport Association (lATA) SAA container, on the main deck, 

using a floor track system based on, and modified from, the incoming passenger 

aircraft main deck seat track installation, similar to the Boeing 757-200PF 

"package freighter" design. 

d) Accommodation for six in the flight deck, with two pilots and two observers 

being accommodated within the original flight deck layout of the incoming 

passenger configuration aircraft (with observers on bulkhead-mounted seats), and 

two supernumerary personnel located just forward of the RCB, identical to the 

Boeing 757-200PF package freighter configuration. 

e) Installation of a new crew entry door (CED), identical to that of the Boeing 757-

200PF, centered at approximately STA 311 on the left-hand side of the fuselage 

forward of the RCB, in place of the forward passenger and service doors existing 

on the incoming passenger configuration aircraft. 

f) Structural modifications related to the installation of the MDCD, CED, RCB, and 

CLS, including, but not necessarily limited to, the floor and fuselage monocoque 

( skinfi·ame-stringer) structures. 

g) Systems modifications related to the air conditioning, communications, electrical 

power, fire protection, flight controls, hydraulics, indicating and recording, 

lighting, pitot-static (navigation), oxygen, as well as water and waste handling, 

based on the 14-P special freighter design, to enable the main deck cargo 

compartment to meet the Class E cargo compartment classification requirements, 

with a one-minute smoke detection system. 

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h) Interior modifications and installations related to side-wall and ceiling liners, new 

flight deck lavatory and emergency equipment. 

i) Retention of all certificated flight performance as well as weight and balance 

limitations (maximum taxi weight, maximum take-off weight, maximum zero fuel 

weight, maximum landing weight and center of gravity range) of the incoming 

passenger configuration aircraft. 

j) Damage tolerance based on structural maintenance inspections featuring a 

minimum of20,000 cycles since modification for initial threshold for new 

structures, and no less than 3,000 cycles between inspections using detail visual 

inspection as basis, for modified, new and affected structures, to be listed as 

Airworthiness Limitation Items in the Maintenance Planning Data document and 

its supplement. 

This petition seeks relief from the requirements of the following sections of 14 CPR, for 

the 15P conversion: 

• § 25.7850), Amendment 25-88, Seats, berths, safety belts, and harnesses 

• § 25.807(g)(l) and (i)(l), Amendment 25-114, Emergency Exits 

• § 25.812(e), Amendment 25-128, Emergency Lighting 

• § 25.813(b)(1) and (6), Amendment 25-128, Emergency Exit Access 

• § 25.1445(a)(2), Amendment 25-0, Equipment Standards for the Oxygen 

Distributing System 

• § 25.1447(c)(1), Amendment 25-116, Equipment Standards for Oxygen 

Dispensing Units 

The following information is provided to support this petition: 

To date, there have been many passenger-to-freighter conversions being carried out by 

the industry and the reconfigured flight deck layout design has accumulated a 

considerable satisfactory service history. 

In accordance with§ 121.583, all persons that may be carried on the flight deck will have 

special training, which includes proper methods for egress from the airplane and use of 

emergency equipment. Limitations will be imposed on the airplane operator to find that 

all occupants are physically able to use the escape means provided. When 

supernumeraries are carried, they will be briefed prior to each flight as to the location and 

use of the emergency egress equipment and the supplemental oxygen equipment. 

Supernumeraries are also prohibited from being in the cargo area during any flight 

operation. These limitations will be included as part of the Airplane Flight Manual 

Supplement (AFMS) similar to that of STC ST03562AT. 

The RCB sliding door will be closed and locked prior to taxi and will not be opened 

again for access to the cargo area until the airplane has parked at its destination. Steps 

will also be taken to ensure that no one is in the cargo area prior to the locking of the 

sliding door before taxi. 

4 
Occupancy of the flight deck area of the 15P-configured airplane is limited to a total of 

six (6) persons, which will consist of supernumeraries as defined by§ 121.583 (a)(1) 

through (a)(8), and personnel permitted on the flight deck as defined by§ 121.547. This 

limitation will be included in the AFMS similar to that of STC ST03562AT. 

The AFMS will include a requirement for the flight crew to brief supernumeraries on the 

use of the escape provisions prior to each flight. 

§ 25.7850), Amendment 25-88, "If the seat backs do not provide a firm handhold, there 

must be a handgrip or rail along each aisle to enable persons to steady themselves while 

using the aisles in moderately rough air." 

Justification: 

Hand holds are not available in the flight deck area due to the space constraint. The 

configuration of the flight deck area with the supernumerary seats' backs attached on the 

RCB does not permit using the seat back as the traditional handhold. The lack of 

handhold is identical to that ofSTA Mobile 757-200SF supernumerary area 

configuration. 

A Petition for Exemption was submitted by STA Mobile in connection with the STA 

Mobile 757-200SF with regards to the equivalent§ 25.785(d) at Amendment 25-32, and 

this resulted in FAA Grant of Exemption No. 9487. 

The flight crew area is limited to the use of operator assigned supernumeraries or flight 

crew (not public passenger) as described by§ 121.583 (a)(1) through (a)(8) and/or 

§ 121.54 7 whom have higher level of training and knowledge of the flight deck area 

layout. There will also be a recommendation to supernumeraries to remain seated with 

their seat belts fastened. Therefore, an acceptable level of safety is provided. 

§ 25.807(g)(l) and (i)(l), Amendment 25-114, "25.807(g)(l): For a passenger seating 

configuration of I to 9 seats, there must be at least one Type IV or larger overwing exit in 

each side of the fuselage or, if overwing exits are not provided, at least one exit in each 

side that meets the minimum dimensions of a Type III exit. 

25.807(i)(1): Ditching emergency exits for passengers. Whether or not ditching 

certification is requested, ditching emergency exits must be provided in accordance with 

the following requirements, tmless the emergency exits required by paragraph (g) of this 

section already meet them: 

(1) For airplanes that have a passenger seating configuration of nine or fewer seats, 

excluding pilot seats, one exit above the waterline in each side of the airplane, meeting at 

least the dimensions of a Type IV exit." 

Justification: 

Flight deck is equipped with a left hand crew entry door (22" x 56"), with a step-up inside 

the aircraft of I 0 inches. This meets the size requirement of a Type III door for the LH 

side of the aircraft. The RH side of the aircraft does not have a Type III door. However, 

the right hand flight deck window will be modified to be openable from the outside to 

serve as a flight crew emergency exit. Both exits are above the waterline, and will be 

5 
equipped with ropes to serve as escape means. Recommended evacuation procedures 

will be briefed to the supernumeraries prior to each flight. Since the supernumeraries 

have a higher level of training and lmowledge of the airplane configuration than a typical 

passenger, an acceptable level of safety is provided. 

The same exemption was granted to the Boeing Package Freighter certified under TCDS 

A2NM, using Exemption No. 4808, and to Precision Conversions' PCP (STC 

ST01529SE), using Exemption No. 8258, using the same justifications. 

§ 25.812(e), Amendment 25-128, "Floor proximity emergency escape path marking 

must provide emergency evacuation guidance for passengers when all sources of 

illumination more than 4 feet above the cabin aisle floor are totally obscured. In the dark 

of the night, the floor proximity emergency escape path marking must enable each 

passenger to--

(1) After leaving the passenger seat, visually identify the emergency escape path along 

the cabin aisle floor to the first exits or pair of exits forward and aft of the seat; and 

(2) Readily identify each exit from the emergency escape path by reference only to 

markings and visual features not more than 4 feet above the cabin floor." 

Justification: 

... the configuration of the converted Boeing Model 757-200 in the flight deck area does 

not provide floor proximity emergency lightings, as required by§ 25.812(e). 

The proximity of the two supernumeraries to the emergency exits, via the left hand Crew 

Entry Door and the right hand flight deck window, provides a level of safety that would 

not be enhanced by the installation of floor proximity emergency lightings. In addition, 

supernumeraries have a higher level of training and lmowledge of the emergency exit 

layout than the typical passenger. Hence, the configuration of the flight deck area 

provides an acceptable level of safety for the supernumeraries. 

The absence of floor proximity emergency exit path marking is identical to the 

configuration of STA Mobile 757-200SF. A Petition for Exemption was submitted by 

STA Mobile for STA Mobile 757-200SF and resulted in FAA Partial Grant of Exemption 

(No. 9487). In Exemption No. 9487, the FAA had granted the exemption based on the 

same justifications described above. The same exemption was granted to Precision 

Conversions' PCP (STC ST01529SE), using Exemption No. 8258, based on the same 

justifications. 

§ 25.813(b), Amendment 25-128, "Adequate space to allow crewmember(s) to assist in 

the evacuation of passengers must be provided as follows: 

(1) Each assist space must be a rectangle on the floor, of sufficient size to enable a 

crewmember, standing erect, to effectively assist evacuees. The assist space must not 

reduce the unobstructed width of the passageway below that required for the exit. 

( 6) There must be a handle, or handles, at each assist space, located to enable the 

crewmember to steady himself or herself: 

(i) While manually activating the assist means (where applicable) and, 

6 
(ii) While assisting passengers during an evacuation." 

Justification: 

The configuration of the flight area does not provide an assist space adjacent to each exit, 

due to the space constraint within the flight deck. However, since the supernumeraries 

will have a higher level of training than a typical passenger, they will have no need for 

crew assistance. In addition, in the relatively small confines of the flight deck area, the 

flight crew can easily provide instmctions and some physical assistance to the 

supernumeraries, if needed. 

The absence of an assist space adjacent to each exit is identical to the configuration of 

STA Mobile 757-200SF. A Petition for Exemption was submitted by STA Mobile for 

STA Mobile 757- 200SF and resulted in FAA Partial Grant of Exemption (No. 9487). In 

Exemption No. 9487, the FAA had granted the exemption based on the same 

justifications described above. The same exemption was granted to the Boeing Package 

Freighter certified under TCDS A2NM, using Exemption No. 4808, and to Precision 

Conversions' PCP (STC ST01529SE), using Exemption No. 8258. 

§ 25.1445(a)(2), Amendment 25-0, "When oxygen is supplied to both crew and 

passengers, the distribution system must be designed for either--

(1) A source of supply for the flight crew on duty and a separate source for the 

passengers and other crewmembers; or 

(2) A common source of supply with means to separately reserve the minimum supply 

required by the flight crew on duty." 

Justification: 

There is no means to separate the means of oxygen to reserve the minimum supply 

required by the flight crew as the supernumeraries occupy the same flight deck area as 

the flight crew. Since the two supernumeraries are co-located within the enlarged 

cockpit, they can communicate directly and receive instructions from the flight crew. 

Moreover, the common oxygen cylinder is able to supply sufficient supplemental 

emergency oxygen for up to six occupants for an ETOPS duration of up to 120 minutes 

The absence of the ability to separate tl1e oxygen supply for the flight crew use is 

identical to that on the Boeing 757-200 Package Freighter certified under TCDS A2NM 

and the Precision Conversions' PCP (STC ST01529SE). In Exemption No. 8258, the 

FAA had granted the exemption based on the same justifications described above. 

§ 25.1447(c)(l), Amendment 25-116, "There must be an oxygen dispensing unit 

connected to oxygen supply terminals immediately available to each occupant wherever 

seated, and at least two oxygen dispensing units connected to oxygen terminals in each 

lavatory. The total number of dispensing units and outlets in the cabin must exceed the 

number of seats by at least 10 percent. The extra units must be as uniformly distributed 

throughout the cabin as practicable. If certification for operation above 30,000 feet is 

requested, the dispensing units providing the required oxygen flow must be automatically 

presented to the occupants before the cabin pressure altitude exceeds 15,000 feet. The 

7 
crew must be provided with a manual means of making the dispensing units immediately 

available in the event of failure ofthe automatic system." 

Justification: 

The two supernumeraries will have two quick -donning type masks similar to the flight 

crew that are not automatically presented. However, the high level of training of the 

supernumeraries and the aural warning system will allow the flight crew to command the 

supernumeraries to don the masks, providing an adequate level of safety to all occupants. 

The lavatory will also be outfitted with a portable walk around oxygen bottle equipped 

with an oxygen mask. This area will not be utilized for takeoff and landing. 

The absence of the automatic presentation of the dispensing units for oxygen use is 

identical to the configuration of STA Mobile 757-200SF. A Petition for Exemption was 

submitted by STA Mobile for STA Mobile 757-200SF and resulted in FAA Partial Grant 

of Exemption (No. 9487). In Exemption No. 9487, the FAA had granted the exemption 

based on the same justifications described above. The same exemption was granted to 

Precision Conversions' PCF (STC ST01529SE), using Exemption No. 8258, based on the 

same justifications. 

Evaluation of Public Interest: 

The presence of trained personnel on board the airplane when cargo is carried will 

enhance flight safety, which is in the public interest. 

Granting this exemption will enhance the utility of the airplane for the operator by 

ensuring that needed cargo management personnel will be available at each flight 

destination. This will reduce shipping costs and transit time, which is in the public 

interest. 

As Boeing 757-200 passenger airplanes are conve1ied into 15P-configured airplanes, 

airlines will replace them with new passenger airplanes which meet newer 14 CFR Part 

25 Amendments. Over time, this will have the effect of raising the safety level of the 

passenger airline fleets, which is in the public interest. 

Petition for Exemption: 

Based on the information provided, STA Mobile, hereby petitions for exemption from the 

following sections of 14 CFR Part 25 for Boeing 757-200 passenger airplanes converted 

to a 15P configuration under FAA STC Project ST14446AT-T to allow the carriage of 

supernumeraries in the flight deck area: 

• § 25.7850), Amendment 25-88, Seats, berths, safety belts, and harnesses 

• § 25.807(g)(1) and (i)(1), Amendment 25-114, Emergency Exits 

• § 25.812(e), Amendment 25-128, Emergency Lighting 

• § 25.813(b)(l) and (6), Amendment 25-128, Emergency Exit Access 

• § 25.1445(a)(2), Amendment 25-0, Equipment Standards for the Oxygen 

Distributing System 

8 
• § 25.1447(c)(1), Amendment 25-116, Equipment Standards for Oxygen 

Dispensing Units 

STA Mobile respectfully requests favorable FAA consideration of this petition. 

Federal Register publication 

The FAA has determined that good cause exists for waiving the requirement for Federal Register 

publication for public comment because the request is identical in all material respects to 

previously granted exemptions; the exemption, if granted, would not set a precedent; and any 

delay in acting on this petition would be detrimental to ST Aerospace Mobile, Inc. 

The FAA's analysis 

The FAA considers the petitioner's proposal to be in the public interest for the following 

reasons: 

The FAA has granted several exemptions for the carriage of supernumeraries on freighter 

airplanes. These supernumeraries are seen as a benefit to airplane safety and efficient operations 

of air cargo and a significant dismption of air commerce could occur if the petition were not 

granted. 

The certification regulations for transport -category airplanes address airplane occupants as being 

either "crew" or "passengers." Due to differences in training, physical capabilities, and other 

factors (such as familiarity with the airplane), the means required by part 25 to address 

emergency evacuation and emergency equipment differ for passengers and crewmembers. 

Because supernumeraries are not crewmembers, they must be considered "passengers" by 

default, with respect to part 25. However, supernumeraries do hold a special status because of 

their training and other factors. The FAA, therefore, has granted certain exemptions to allow the 

carriage of supernumeraries on freighter airplanes without compliance with all of the part 25 

standards for passengers, provided that certain other conditions are met. Those conditions have 

varied, depending on the airplane design, the nature of the proposals under consideration, and the 

number and location of persons to be carried. 

The handhold requirement of§ 25.785G), at Amendment 25-88, is to ensure that occupants have 

a means to steady themselves in moderately rough air while traversing the main aisles of typical 

passenger airplanes. The petitioner states that the lack-of-handhold issue is identical to that of 

the ST Aerospace Mobile, Inc., 757-200SF supernumerary-area configuration for which the FAA 

granted relief via Exemption No. 9487. On the proposed airplane, the FAA requires the same 

limitation for a crew-operated visual/aural alerting system as stated in Exemption No. 9487. 

This alerting system enables the crew to indicate, at the onset of turbulence, that supernumeraries 

must return to their seats. The alert must be recognized in accessible areas in the supernumerary 

compartment and lavatory and indicate, during turbulence, those persons must return to their 

seats. 

The emergency exit provided on the right side of the airplane-the right flight deck windowdoes not meet the minimum size for a Type III exit as required by§ 25.807(g)(1). The Boeing 

Company has tested the usability of such a right flight deck window. Results indicate that the 

9 
window can be used for an exit-with the evacuation means provided-for a maximum of seven 

people in the flight deck of the Boeing Model 757-200PF. Also, the four non-crewmembers of 

the airplane will have a higher level of training and be physically more capable of evacuating the 

airplane by using the smaller exit opening provided on the right side of the airplane than would 

typical passengers. 

The emergency exit provided on the right side of the airplane-the right flight deck windowalso does not meet the minimum size for a Type IV exit as required by§ 25.807(i)(l) for a 

ditching exit. As discussed above, the utility of the right flight deck window and its usability 

with the evacuation means provided has been demonstrated for a maximum occupancy of seven 

persons on the flight deck of the Boeing Model 757-200PF. This demonstration would also 

apply to evacuating the airplane for ditching. Furthermore, the four non-crewmembers of the 

airplane will have a higher level of training and be physically more capable of evacuating the 

airplane by using the reduced exit opening on the right side of the airplane than would typical 

passengers. It should be noted that, if life-rafts must be installed for flights over water, they must 

be of a design that can be launched out of the right flight deck window. 

As stated above, because of their training and physical capabilities, as well as other factors, flight 

crewmembers are different than typical passengers, and as such, the means required by part 25 to 

enable flight crewmembers to reach the ground are different from those required for passengers. 

As an example, ropes are allowed as the sole means of escape for flight crewmembers, but slides 

or equivalent means are required for passengers. 

Although supernumeraries must be considered "passengers" by default (because they are not 

crewmembers) under part 25, the FAA recognizes that supernumeraries normally have unique 

training to perform their roles on an airplane. As indicated above, the FAA has previously 

granted exemptions to allow the carriage of supernumeraries on cargo airplanes without 

complying with all of the part 25 requirements applicable to passengers. 

The petitioner has proposed to not install an assist means at the crew entry door. We have 

reviewed figure 2 in the information submitted by the petitioner, and confirmed with a phone call 

with the petitioner on August 15,2014, that the intent of the petitioner is to also request relief 

from the requirements of§ 25.810(a)(l). This section requires the passenger emergency exits to 

be equipped with a self-supporting slide or equivalent assist means. ST Aerospace Mobile, Inc. 

has proposed to install descent devices (commonly known as inertia reels) at the crew entry door 

emergency exit. 

The issue of whether inertia reels with harnesses for trained supernumeraries provide an 

acceptable alternative to the escape slides required by part 25 for passengers is discussed in some 

length in Exemptions No. 4808 and 4808A. (The FAA granted those exemptions to the Boeing 

Commercial Airplane Group in 1987 and 1997, respectively.) This issue is also discussed in 

Exemption No. 5993A, which the FAA granted in 1995 to the Boeing Commercial Airplane 

Group for Boeing 767-300F airplanes. 

The FAA recognizes that supernumeraries, as opposed to passengers, may be selected and 

trained appropriately in the use of escape ropes and inertia reels and harnesses. We consider that 

10 
the petitioner's proposed installation of inertia reels and harnesses at the emergency exit crew 

entry door and retention of the existing escape ropes installed for the flight deck window exits on 

the left and right side provides an adequate level of safety to supernumeraries for the petitioner's 

airplane configuration. 

The petitioner requested an exemption from§ 25.812(e) that requires floor-proximity emergency 

escape-path markings in the passenger areas of the airplane. During the evaluation of this 

petition, the FAA determined that the original certification basis for the 757- 200 did not include 

Amendment 25-58, which codified the requirements for the floor-proximity emergency escapepath marking requirements. The petitioner has volunteered to step up to this amendment level of 

§ 25.812 and then request an exemption from that requirement. The FAA has elected to revert 

the petitioner's certification basis to Amendment 25-32 for§ 25.812, which does not include the 

floor-proximity emergency escape-path marking requirements rather than grant an exemption 

from that requirement. 

The petitioner's Boeing Model 757-200 airplanes have a crew entry door on the left and the 

number 2 flight deck windows, left and right, available for evacuation. However, the 

configuration does not provide an assist space or an assist handle next to the exit to allow a crew 

member to assist in the evacuation of the supernumeraries as required by§ 25.8l3(b). With 

respect to the lack of an assist space and assist handle adjacent to the crew entry door on the left, 

the FAA has determined that the supernumeraries will have a higher level of training than a 

typical passenger, and will therefore have less need for crew assistance. Additionally, in the 

relatively small confines of the flight deck and supernumerary area, the flightcrew can easily 

provide instructions and some physical assistance, if needed. The FAA considers that an assist 

space and assist handle are not necessary in this case due to the size of the exit and the inertial 

reel assist means provided with the number of occupants, and to the higher level of training of 

the occupants. 

The petitioner has requested relief from the requirements of§ 25.1445(a)(2) which require that 

when a single source of oxygen is provided for the flightcrew and passengers, a means must be 

provided to separately reserve the minimum supply required by the flightcrew on duty. The 

petitioner has proposed a design of the system that is intended to provide oxygen to four 

supernumeraries and the flightcrew, as if they were all required flight crewmembers. Supplying 

all six occupants as if they were all flightcrew on duty in the flight deck would comply with the 

regulations and thus, would not require an exemption. However, the amount of oxygen must be 

sufficient for operational requirements for the airplane mission. 

The FAA considers that the supernumeraries should have an oxygen system that is comparable to 

that of passengers. However, taking into account the extra knowledge and training that these 

persons will have, it is not necessary that an equivalent system be installed. Section 

25.1447(c)(l) requires automatic presentation of the oxygen dispensing units. For seated 

passengers in typical passenger airplanes, the automatic presentation of masks throughout the 

cabin indicates the need to don an oxygen mask. Supernumeraries on the petitioner's Boeing 

Model 757 airplanes will not have this indication. In order for an acceptable level of safety to be 

provided, an automatically activated aural/visual decompression signal must be immediately 

11 
recognizable throughout the supernumerary seating area and the lavatory. Operation of this 

signal must be automatic with flightcrew manual action as a backup. 

Additionally, the petitioner proposed to provide supernumeraries with a portable walk-around 

oxygen bottle equipped with a supplemental passenger oxygen mask when accessing the 

lavatory. To ensure adequate hypoxia protection during non-sedentary use, all of the oxygen 

units must meet the requirements for flightcrew oxygen equipment(§ 25.1443(a) or (b)), or the 

equipment must be shown to protect the supernumerary from hypoxia at an activity level 

required to return to his or her seat following a rapid decompression to 25,000 feet cabin altitude. 

One acceptable means of compliance is the use of a continuous-flow passenger oxygen mask that 

meets FAA Technical Standard Order TSO-C64a, or later revision, and is approved for use up to 

at least 40,000 feet cabin altitude, and is connected to an oxygen bottle that supplies a flow rate 

of at least 4 liters per minute NTPD (Normal Temperature and Pressure Dry) at a cabin altitude 

of23,000 feet. If the oxygen bottle regulator has more than one flow rate it must be set to 4 

liters per minute NTPD. 

The non-auto presenting oxygen dispensing units at the supernumeraries' seats and the portable 

oxygen unit must still meet § 25.1449, which states that there must be a means for the crew to 

determine whether oxygen is being delivered to the dispensing units. The FAA has determined 

that it would be an acceptable means of compliance to train the supernumeraries in making this 

determination and to provide oxygen flow indication in the oxygen equipment. 

Section 25.1447(c)(1) also requires 10% extra oxygen masks. The intent is that these masks will 

be used by flight attendants and children sitting on passengers' laps. Since neither will be onboard the airplane, installing 1 0% extra oxygen masks is not required. 

Supernumeraries must be trained regarding the location and use of oxygen equipment and the 

alerts that indicate the need to don oxygen equipment. The oxygen units must be sized 

adequately for continuous and uninterrupted use during worst-case flight duration following 

decompression. 

The FAA's decision 

In consideration of the foregoing, I find that a partial grant of exemption is in the public interest. 

Therefore, pursuant to the authority contained in 49 U.S.C. §§ 40113 and 44701, delegated to me 

by the Administrator, ST Aerospace Mobile, Inc., is hereby granted a partial exemption from 14 

CFR §§ 25.785G), 25.807(g)(1) and (i)(l), 25.810(a)(1), 25.813(b)(1) and (6), 25.1445(a)(2) and 

25.1447(c)(l) to the extent necessary to allow type certification of Boeing Model 757-200 series 

airplanes with provisions for the carriage of supernumeraries. The petitioner is not granted an 

exemption from§ 25.812(e), Amendment 25-128. 

The following conditions apply and limitations numbers 1 through 7, S.d, and the preflight 

briefings required by 7 and 9, below, must be documented in the limitations section of the 

airplane flight manual: 

I. A maximum of four supernumeraries may occupy the area on the flight deck. 

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2. The supernumeraries are limited to the categories specified in§§ 121.583(a)(l) through 

121.583(a)(8). 

3. Supernumeraries are prohibited from being in the cargo area during any flight operation. The 

pre-flight briefing must inform supernumeraries of this requirement. 

4. Prior to each flight, a flightcrew member must brief each supernumerary on the use of the 

exits, assist means, and emergency equipment. 

5. The operator must determine that each supernumerary is physically able and trained to 

accomplish the necessary emergency procedures. 

6. A flightcrew-operated aural or visual annunciation that would be recognized in the 

supernumerary seating area and lavatory must be installed to indicate, during turbulence, that 

persons must return to their seats. Appropriate procedures/limitations must be established to 

ensure that the flightcrew signals the supernumeraries to return to their seats at the onset of 

turbulence and for landing. 

7. Decompression Alert: 

An automatically activated aural decompression signal must be present and immediately 

recognizable in the lavatory to notify supernumeraries when to don oxygen masks. The 

pre-flight briefing must include training in the sound of the alert, the meaning of the alert, 

and the response to the alert, and cover procedures for donning the masks and activating 

the flow of oxygen. 

8. Supernumeraries Fixed and Portable Oxygen: 

a. There must be at least one fixed non-automatically presenting oxygen unit installed 

and located such that each occupant can don a mask and can simply activate the 

oxygen flow while seated. The oxygen masks must be within easy reach of the 

supernumeraries while seated. The unit must provide an indication to the user that 

oxygen is flowing. 

b. There must be at least one portable oxygen unit with a mask connected to it located in 

the lavatory. The unit must provide an indication to the user that oxygen is flowing. 

c. The oxygen units must meet the performance requirements of§ 25.1443(a) or 

§ 25.144 3 (b), or the equipment must be shown to protect the supernumerary from 

hypoxia at an activity level required to return to his or her seat following a rapid 

decompression to 25,000 feet cabin altitude. 

d. The supernumeraries must be trained in the use of the fixed and portable oxygen 

units. The supernumeraries must also be trained in malcing the determination whether 

oxygen is being delivered to the dispensing units. 

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e. The fixed and portable oxygen units must be sized adequately for continuous and 

uninterrupted use during worst -case flight duration following decompression, or must 

be of sufficient duration to allow the supernumeraries to return to their seats where 

additional oxygen is readily accessible for the remainder of the decompression. 

9. Placards: 

Placards are to be located outside of the cargo compartment, in a conspicuous location 

either on or adjacent to the smoke barrier doors. The placards must indicate the 

following: 

a. Do not occupy the Class E cargo compartment during taxi, take-off, and 

landing and flight. 

b. The smoke barrier must be secured (i.e., the doors must be closed) except 

when entering or leaving the cargo compartment. 

The pre-flight briefing must inform supernumeraries of these requirements. 

10. Alerting Requirements: 

a. Must be distinctive and effective. The alert for turbulence must be clearly 

distinguishable from the alerts for decompression/fire/smoke. 

b. Visual alerts must be visible from all occupant locations and orientations, during all 

expected operational conditions including a rapid decompression where moisture in 

the air may condense. 

c. Aural alerts must be loud enough to be heard during all expected operational 

conditions including a rapid decompression where the ambient noise level will 

mcrease. 

11. A standard airplane public address (PA) system must be installed. It must be audible 

tln·oughout the supernumeraries' seating area. 

. Issued in Renton, Washington, on SEP 2 3 2014 

Dionne Palermo 

Acting Manager, Transport Airplane Directorate 

Aircraft Certification Service 

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