Special Conditions: Embraer S.A., Model EMB-550 Airplanes; Electrical/Electronic Equipment Bay Fire Detection and Smoke Penetration, 75071-75073 [2012-30493]

Download as PDF Federal Register / Vol. 77, No. 244 / Wednesday, December 19, 2012 / Proposed Rules 6. In lieu of § 25.125(b)(2)(ii)(B), we propose paragraph § 25.125(b)(2)(ii)(C) be removed and replaced by the following requirements: In lieu of § 25.125(b)(2)(ii)(B) and § 25.125(b)(2)(ii)(C) Landing. (B) A speed that provides the maneuvering capability specified in § 25.143(h) with the landing ice accretion defined in appendix C. 7. In lieu of, § 25.143(j)(2)(i) we propose the following requirements for controllability and maneuverability: In lieu of § 25.143(j)(2)(i) General. (i) The airplane is controllable in a pull-up maneuver up to 1.5 g load factor or lower if limited by AOA protection; and 8. In lieu of § 25.207, Stall warning, to read as the requirements defined in SC Part I., Section 4. Ali Bahrami, Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 2012–30441 Filed 12–18–12; 8:45 am] BILLING CODE 4910–13–P DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 25 [Docket No. FAA–2012–1292; Notice No. 25– 12–17–SC] Special Conditions: Embraer S.A., Model EMB–550 Airplanes; Electrical/ Electronic Equipment Bay Fire Detection and Smoke Penetration Federal Aviation Administration (FAA), DOT. ACTION: Notice of proposed special conditions. AGENCY: This action proposes special conditions for the Embraer S.A. Model EMB–550 airplane. This airplane will have novel or unusual design features, specifically distributed electrical and electronic equipment bays in pressurized areas of the airplane. Older transport category airplane electrical/ electronic equipment bay installations are located in the lower lobe where the flightcrew could determine the origin of smoke or fire by a straightforward airplane flight manual procedure. In distributed electrical/electronic bay installations it is not as straightforward. The FAA has no requirement for smoke and/or fire detection in the electrical/ electronic equipment bays. To ensure effective mitigation of fires, the FAA proposes these special conditions. The applicable airworthiness regulations do not contain adequate or appropriate safety standards for this design feature. wreier-aviles on DSK5TPTVN1PROD with SUMMARY: VerDate Mar<15>2010 15:12 Dec 18, 2012 Jkt 229001 These proposed special conditions contain the additional safety standards that the Administrator considers necessary to establish a level of safety equivalent to that established by the existing airworthiness standards. DATES: Send your comments on or before February 4, 2013. ADDRESSES: Send comments identified by docket number FAA–2012–XXXX using any of the following methods: • Federal eRegulations Portal: Go to http://www.regulations.gov/and follow the online instructions for sending your comments electronically. • Mail: Send comments to Docket Operations, M–30, U.S. Department of Transportation (DOT), 1200 New Jersey Avenue SE., Room W12–140, West Building Ground Floor, Washington, DC 20590–0001. • Hand Delivery or Courier: Take comments to Docket Operations in Room W12–140 of the West Building Ground Floor at 1200 New Jersey Avenue SE., Washington, DC, between 8 a.m. and 5 p.m., Monday through Friday, except federal holidays. • Fax: Fax comments to Docket Operations at 202–493–2251. Privacy: The FAA will post all comments it receives, without change, to http://www.regulations.gov/, including any personal information the commenter provides. Using the search function of the docket Web site, anyone can find and read the electronic form of all comments received into any FAA docket, including the name of the individual sending the comment (or signing the comment for an association, business, labor union, etc.). DOT’s complete Privacy Act Statement can be found in the Federal Register published on April 11, 2000 (65 FR 19477–19478), as well as at http://DocketsInfo.dot.gov/. Docket: Background documents or comments received may be read at http://www.regulations.gov/ at any time. Follow the online instructions for accessing the docket or go to the Docket Operations in Room W12–140 of the West Building Ground Floor at 1200 New Jersey Avenue SE., Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, except federal holidays. FOR FURTHER INFORMATION CONTACT: Robert C. Jones, FAA, Propulsion and Mechanical Systems Branch, ANM–112, Transport Airplane Directorate, Aircraft Certification Service, 1601 Lind Avenue SW., Renton, Washington 98057–3356; telephone 425–227–1234; facsimile 425–227–1149. SUPPLEMENTARY INFORMATION: PO 00000 Frm 00007 Fmt 4702 Sfmt 4702 75071 Comments Invited We invite interested people to take part in this rulemaking by sending written comments, data, or views. The most helpful comments reference a specific portion of the special conditions, explain the reason for any recommended change, and include supporting data. We will consider all comments we receive on or before the closing date for comments. We may change these special conditions based on the comments we receive. Background On May 14, 2009, Embraer S.A. applied for a type certificate for their new Model EMB–550 airplane. The Model EMB–550 airplane is the first of a new family of jet airplanes designed for corporate flight, fractional, charter, and private owner operations. The aircraft has a conventional configuration with a low wing and T-tail empennage. The primary structure is metal with composite empennage and control surfaces. The Model EMB–550 airplane is designed for 8 passengers, with a maximum of 12 passengers. It is equipped with two Honeywell HTF7500–E medium bypass ratio turbofan engines mounted on aft fuselage pylons. Each engine produces approximately 6,540 pounds of thrust for normal takeoff. The primary flight controls consist of hydraulically powered fly-by-wire elevators, aileron and rudder, controlled by the pilot or copilot sidestick. The Model EMB–550 airplane has electrical/electronic equipment bays distributed throughout the airplane; three of them are in the pressurized area. The current airworthiness requirements do not contain adequate or appropriate safety standards regarding smoke/fire detection and protection against penetration of hazardous quantities of smoke from equipment bays into occupied areas of the airplane for this type of airplane configuration. Type Certification Basis Under the provisions of Title 14, Code of Federal Regulations (14 CFR) 21.17, Embraer S.A. must show that the Model EMB–550 airplane meets the applicable provisions of part 25, as amended by Amendments 25–1 through 25–127 thereto. If the Administrator finds that the applicable airworthiness regulations (i.e., 14 CFR part 25) do not contain adequate or appropriate safety standards for the Model EMB–550 airplane because of a novel or unusual design feature, special conditions are E:\FR\FM\19DEP1.SGM 19DEP1 75072 Federal Register / Vol. 77, No. 244 / Wednesday, December 19, 2012 / Proposed Rules prescribed under the provisions of § 21.16. Special conditions are initially applicable to the model for which they are issued. Should the type certificate for that model be amended later to include any other model that incorporates the same or similar novel or unusual design feature, the special conditions would also apply to the other model under § 21.101. In addition to the applicable airworthiness regulations and special conditions, the Model EMB–550 airplane must comply with the fuel vent and exhaust emission requirements of 14 CFR part 34 and the noise certification requirements of 14 CFR part 36 and the FAA must issue a finding of regulatory adequacy under § 611 of Public Law 92–574, the ‘‘Noise Control Act of 1972.’’ The FAA issues special conditions, as defined in 14 CFR 11.19, in accordance with § 11.38, and they become part of the type-certification basis under § 21.17(a)(2). wreier-aviles on DSK5TPTVN1PROD with Novel or Unusual Design Features The Model EMB–550 airplane will incorporate the following novel or unusual design features: The Model EMB–550 airplane has distributed electrical and electronic equipment bays that were not envisioned at the time this rule was made. Discussion In general, smoke and fire detection systems are designed to: • Automatically shut off power to the affected equipment, • If necessary, reconfigure the environmental control systems to control any smoke resulting from a fire or overheat condition, and • Alert the flightcrew to the existence of the fire. Most airplanes certified under part 25 have one or two electrical equipment bays located in the lower lobe, adjacent to pressure regulator/outflow valves or vents. If a fire occurs in an electrical equipment bay, any smoke is drawn toward the outflow valves or vents and is discharged from the airplane without entering occupied areas. In the event of a smoke or fire in one of the electrical equipment bays, the procedures to isolate the bay on some airplanes requires the flightcrew to use trial and error to determine whether or not the source is in a particular electrical equipment bay. However, with this approach, the flightcrew does not know where the fire or smoke is because it is difficult to identify the source, especially during changes of phases of flight (e.g., climbing or descending) or VerDate Mar<15>2010 15:12 Dec 18, 2012 Jkt 229001 system transients (e.g., changes in the airflow from the environmental control system). This trial-and-error approach may be acceptable for aircraft with no more than two electrical equipment bays, both located in the lower lobe. In this case, a fire in an electrical equipment bay is in either one bay or the other. However, for an aircraft with three or more electrical equipment bays, in the time it takes to determine the source of smoke, the fire could spread, generating even more smoke and damage. In the Model EMB–550 airplane, electrical equipment bays are distributed throughout the airplane in the pressurized compartment. Section 25.857 requires that cargo compartments have means to prevent hazardous quantities of smoke or fire extinguishing agent from penetrating into occupied areas of the airplane. However, the applicable airworthiness regulations do not address the following: • Preventing hazardous quantities of smoke or extinguishing agent originating from the electrical equipment bays from penetrating into occupied areas of the airplane; or • Installing smoke or fire detectors in electrical equipment bays. The FAA determined that the Model EMB–550 needs a means to detect smoke or fire in each electrical equipment bay that is located in the pressurized cabin. This means must indicate in which bay the smoke or fire occurs, and ensure that the flightcrew can depower it. For situations in which it may be impossible for the flightcrew to shut down all the equipment in the bay due to the use of critical or essential equipment located in it, Embraer S.A. shall conduct an analysis to: • Specify the criteria for shutting down specific electrical equipment in the electrical equipment bay that can be shut down, • Demonstrate that remaining electrical equipment is protected against fire propagation, such as thermal protection, fire containment, and other systems as addressed in Advisory Circular 25–16, Electrical Fault and Fire Prevention and Protection, dated April 5, 1991. The criteria developed for aircraft designs that incorporate distributed electrical/electronic equipment bays are based upon existing smoke/fire detection and smoke penetration guidance and acceptable past practices. Sections 25.831(b), 25.831(c), 25.831(d), and 25.869(a) provide the general requirements that apply to electrical/ electronic equipment smoke penetration and evacuation. Flight tests are conducted to demonstrate compliance; PO 00000 Frm 00008 Fmt 4702 Sfmt 4702 however, the amount of smoke generated and flight test conditions have been highly variable. The special conditions below require that there must be a means to detect smoke or fire in each electrical/ electronic equipment bay located in the pressurized compartment. They also include requirements to prevent propagation of hazardous quantities of smoke or fire extinguishing agent throughout the passenger cabin. Applicability As discussed above, these special conditions are applicable to the Model EMB–550 airplane. Should Embraer S.A. apply at a later date for a change to the type certificate to include another model incorporating the same novel or unusual design feature, the special conditions would apply to that model as well. Conclusion This action affects only certain novel or unusual design features on one model of airplanes. It is not a rule of general applicability. List of Subjects in 14 CFR Part 25 Aircraft, Aviation safety, Reporting and recordkeeping requirements. The authority citation for these special conditions is as follows: Authority: 49 U.S.C. 106(g), 40113, 44701, 44702, 44704. The Proposed Special Conditions Accordingly, the Federal Aviation Administration (FAA) proposes the following special conditions as part of the type certification basis for Embraer S.A. Model EMB–550 airplanes. 1. Requirements to prevent propagation of smoke that originates in electrical equipment bays from entering the passenger cabin and flight deck: a. To prevent such propagation, means to prevent hazardous quantities of smoke originating from the electrical equipment bays from incapacitating passengers and crew must be demonstrated. The demonstrations must include flight tests, and shall be conducted for all dispatchable system configurations. b. A small quantity of smoke may enter an occupied area only under the following conditions: i. The smoke enters occupied areas during system transients from below the deck or main deck sources. No sustained smoke penetration beyond that from environmental control system transients is permitted, ii. Penetration of the small quantity of smoke is a dynamic event, involving either dissipation or mobility. E:\FR\FM\19DEP1.SGM 19DEP1 Federal Register / Vol. 77, No. 244 / Wednesday, December 19, 2012 / Proposed Rules wreier-aviles on DSK5TPTVN1PROD with Dissipation is rapid dilution of the smoke by ventilation air. Mobility is rapid movement of the smoke into and out of the occupied area. In no case should a light haze indicative of stagnant airflow form, as this indicates that the ventilation system is failing to meet the requirements of 14 CFR 25.831, iii. The smoke from a source below the main deck must not rise above armrest height on the main deck, and iv. The smoke from a source in the main deck must dissipate rapidly via dilution with fresh air and be evacuated from the airplane. The Airplane Flight Manual (AFM) must include procedures to evacuate smoke from the occupied areas. To demonstrate that the quantity of smoke is small, a flight test must be conducted which simulates the emergency procedures used in the event of a fire during flight, including the use of VMO/MMO descent profiles and a simulated landing, if such conditions are specified in the emergency procedure. 2. Requirement for smoke or fire detection in electrical/electronic equipment bays: A smoke or fire detection system compliant with §§ 25.855(a), (b), (c), and (d); and § 25.858 must be provided for each electrical/electronic equipment bay in the pressurized cabin. Each system must provide a visual indication to the flight deck within one minute after the start of a fire. Airplane flight tests must be conducted to show compliance with these requirements, and the performance of the detectors must be shown in accordance with Advisory Circular 25–9A, Smoke Detection, Penetration, and Evacuation Tests and Related Flight Manual Emergency Procedures, or other means acceptable to the FAA. 3. Requirement for AFM procedures safety analysis: It shall be demonstrated that the AFM procedures to shut down electrical/electronic equipment bays, or part of them, in case of smoke/fire detection, do not compromise the safe operation of the aircraft. If a procedure requests to shut down only part of the equipment, the remaining equipment shall be incorporated with safety precautions against fire propagation. Issued in Renton, Washington, on December 13, 2012. Ali Bahrami, Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 2012–30493 Filed 12–18–12; 8:45 am] BILLING CODE 4910–13–P VerDate Mar<15>2010 15:12 Dec 18, 2012 Jkt 229001 DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. FAA–2011–1285; Directorate Identifier 2010–SW–073–AD] RIN 2120–AA64 Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters Federal Aviation Administration (FAA), DOT. ACTION: Supplemental notice of proposed rulemaking (SNPRM); reopening of comment period. AGENCY: We are revising an earlier proposed airworthiness directive (AD) for Eurocopter Deutschland GmbH (Eurocopter) Model BO–105A, BO– 105C, BO–105LS A–1, BO–105LS A–3, and BO–105S helicopters, which proposed inspecting for debonding of the erosion protective shell (abrasion strip) on the leading edge of each main rotor blade. This SNPRM proposes to revise those inspection requirements by identifying specific dates of replacement of the applicable parts and identifying a specific inspection method for debonding of an abrasion strip. DATES: We must receive comments on this proposed AD by February 4, 2013. ADDRESSES: You may send comments by any of the following methods: • Federal eRulemaking Docket: Go to http://www.regulations.gov. Follow the online instructions for sending your comments electronically. • Fax: 202–493–2251. • Mail: Send comments to the U.S. Department of Transportation, Docket Operations, M–30, West Building Ground Floor, Room W12–140, 1200 New Jersey Avenue SE., Washington, DC 20590–0001. • Hand Delivery: Deliver to the ‘‘Mail’’ address between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. SUMMARY: 75073 For service information identified in this proposed AD, contact American Eurocopter Corporation, 2701 N. Forum Drive, Grand Prairie, Texas 75052; telephone (972) 641–0000 or (800) 232– 0323; fax (972) 641–3775; or at http:// www.eurocopter.com/techpub. You may review the referenced service information at the FAA, Office of the Regional Counsel, Southwest Region, 2601 Meacham Blvd., Room 663, Fort Worth, Texas 76137. FOR FURTHER INFORMATION CONTACT: Jim Grigg, Manager, Safety Management Group, Rotorcraft Directorate, FAA, 2601 Meacham Blvd., Fort Worth, Texas 76137; telephone (817) 222–5110; email jim.grigg@faa.gov. SUPPLEMENTARY INFORMATION: Comments Invited We invite you to participate in this rulemaking by submitting written comments, data, or views. We also invite comments relating to the economic, environmental, energy, or federalism impacts that might result from adopting the proposals in this document. The most helpful comments reference a specific portion of the proposal, explain the reason for any recommended change, and include supporting data. To ensure the docket does not contain duplicate comments, commenters should send only one copy of written comments, or if comments are filed electronically, commenters should submit only one time. We will file in the docket all comments that we receive, as well as a report summarizing each substantive public contact with FAA personnel concerning this proposed rulemaking. Before acting on this proposal, we will consider all comments we receive on or before the closing date for comments. We will consider comments filed after the comment period has closed if it is possible to do so without incurring expense or delay. We may change this proposal in light of the comments we receive. Examining the AD Docket Discussion You may examine the AD docket on the Internet at http:// www.regulations.gov or in person at the Docket Operations Office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this proposed AD, the economic evaluation, any comments received, and other information. The street address for the Docket Operations Office (telephone 800–647–5527) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt. On November 29, 2011, we issued a proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an AD that would apply to Eurocopter Model BO–105A, BO–105C, BO–105LS A–1, BO–105LS A–3, and BO–105S helicopters with a main rotor blade, part number (P/N) 105–15103, 105–15141, 105–15141V001, 105– 15143, 105–15150, 105–15150V001, 105–15152, 105–81013, 105–87214, 1120–15101, or 1120–15103; where the main rotor blade erosion protective shell was replaced between September 2006 PO 00000 Frm 00009 Fmt 4702 Sfmt 4702 E:\FR\FM\19DEP1.SGM 19DEP1

Agencies

[Federal Register Volume 77, Number 244 (Wednesday, December 19, 2012)]
[Proposed Rules]
[Pages 75071-75073]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2012-30493]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 25

[Docket No. FAA-2012-1292; Notice No. 25-12-17-SC]


Special Conditions: Embraer S.A., Model EMB-550 Airplanes; 
Electrical/Electronic Equipment Bay Fire Detection and Smoke 
Penetration

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed special conditions.

-----------------------------------------------------------------------

SUMMARY: This action proposes special conditions for the Embraer S.A. 
Model EMB-550 airplane. This airplane will have novel or unusual design 
features, specifically distributed electrical and electronic equipment 
bays in pressurized areas of the airplane. Older transport category 
airplane electrical/electronic equipment bay installations are located 
in the lower lobe where the flightcrew could determine the origin of 
smoke or fire by a straightforward airplane flight manual procedure. In 
distributed electrical/electronic bay installations it is not as 
straightforward. The FAA has no requirement for smoke and/or fire 
detection in the electrical/electronic equipment bays. To ensure 
effective mitigation of fires, the FAA proposes these special 
conditions. The applicable airworthiness regulations do not contain 
adequate or appropriate safety standards for this design feature. These 
proposed special conditions contain the additional safety standards 
that the Administrator considers necessary to establish a level of 
safety equivalent to that established by the existing airworthiness 
standards.

DATES: Send your comments on or before February 4, 2013.

ADDRESSES: Send comments identified by docket number FAA-2012-XXXX 
using any of the following methods:
     Federal eRegulations Portal: Go to http://www.regulations.gov/and follow the online instructions for sending your 
comments electronically.
     Mail: Send comments to Docket Operations, M-30, U.S. 
Department of Transportation (DOT), 1200 New Jersey Avenue SE., Room 
W12-140, West Building Ground Floor, Washington, DC 20590-0001.
     Hand Delivery or Courier: Take comments to Docket 
Operations in Room W12-140 of the West Building Ground Floor at 1200 
New Jersey Avenue SE., Washington, DC, between 8 a.m. and 5 p.m., 
Monday through Friday, except federal holidays.
     Fax: Fax comments to Docket Operations at 202-493-2251.
    Privacy: The FAA will post all comments it receives, without 
change, to http://www.regulations.gov/, including any personal 
information the commenter provides. Using the search function of the 
docket Web site, anyone can find and read the electronic form of all 
comments received into any FAA docket, including the name of the 
individual sending the comment (or signing the comment for an 
association, business, labor union, etc.). DOT's complete Privacy Act 
Statement can be found in the Federal Register published on April 11, 
2000 (65 FR 19477-19478), as well as at http://DocketsInfo.dot.gov/.
    Docket: Background documents or comments received may be read at 
http://www.regulations.gov/ at any time. Follow the online instructions 
for accessing the docket or go to the Docket Operations in Room W12-140 
of the West Building Ground Floor at 1200 New Jersey Avenue SE., 
Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, 
except federal holidays.

FOR FURTHER INFORMATION CONTACT: Robert C. Jones, FAA, Propulsion and 
Mechanical Systems Branch, ANM-112, Transport Airplane Directorate, 
Aircraft Certification Service, 1601 Lind Avenue SW., Renton, 
Washington 98057-3356; telephone 425-227-1234; facsimile 425-227-1149.

SUPPLEMENTARY INFORMATION: 

Comments Invited

    We invite interested people to take part in this rulemaking by 
sending written comments, data, or views. The most helpful comments 
reference a specific portion of the special conditions, explain the 
reason for any recommended change, and include supporting data.
    We will consider all comments we receive on or before the closing 
date for comments. We may change these special conditions based on the 
comments we receive.

Background

    On May 14, 2009, Embraer S.A. applied for a type certificate for 
their new Model EMB-550 airplane. The Model EMB-550 airplane is the 
first of a new family of jet airplanes designed for corporate flight, 
fractional, charter, and private owner operations. The aircraft has a 
conventional configuration with a low wing and T-tail empennage. The 
primary structure is metal with composite empennage and control 
surfaces. The Model EMB-550 airplane is designed for 8 passengers, with 
a maximum of 12 passengers. It is equipped with two Honeywell HTF7500-E 
medium bypass ratio turbofan engines mounted on aft fuselage pylons. 
Each engine produces approximately 6,540 pounds of thrust for normal 
takeoff. The primary flight controls consist of hydraulically powered 
fly-by-wire elevators, aileron and rudder, controlled by the pilot or 
copilot sidestick.
    The Model EMB-550 airplane has electrical/electronic equipment bays 
distributed throughout the airplane; three of them are in the 
pressurized area. The current airworthiness requirements do not contain 
adequate or appropriate safety standards regarding smoke/fire detection 
and protection against penetration of hazardous quantities of smoke 
from equipment bays into occupied areas of the airplane for this type 
of airplane configuration.

Type Certification Basis

    Under the provisions of Title 14, Code of Federal Regulations (14 
CFR) 21.17, Embraer S.A. must show that the Model EMB-550 airplane 
meets the applicable provisions of part 25, as amended by Amendments 
25-1 through 25-127 thereto.
    If the Administrator finds that the applicable airworthiness 
regulations (i.e., 14 CFR part 25) do not contain adequate or 
appropriate safety standards for the Model EMB-550 airplane because of 
a novel or unusual design feature, special conditions are

[[Page 75072]]

prescribed under the provisions of Sec.  21.16.
    Special conditions are initially applicable to the model for which 
they are issued. Should the type certificate for that model be amended 
later to include any other model that incorporates the same or similar 
novel or unusual design feature, the special conditions would also 
apply to the other model under Sec.  21.101.
    In addition to the applicable airworthiness regulations and special 
conditions, the Model EMB-550 airplane must comply with the fuel vent 
and exhaust emission requirements of 14 CFR part 34 and the noise 
certification requirements of 14 CFR part 36 and the FAA must issue a 
finding of regulatory adequacy under Sec.  611 of Public Law 92-574, 
the ``Noise Control Act of 1972.''
    The FAA issues special conditions, as defined in 14 CFR 11.19, in 
accordance with Sec.  11.38, and they become part of the type-
certification basis under Sec.  21.17(a)(2).

Novel or Unusual Design Features

    The Model EMB-550 airplane will incorporate the following novel or 
unusual design features: The Model EMB-550 airplane has distributed 
electrical and electronic equipment bays that were not envisioned at 
the time this rule was made.

Discussion

    In general, smoke and fire detection systems are designed to:
     Automatically shut off power to the affected equipment,
     If necessary, reconfigure the environmental control 
systems to control any smoke resulting from a fire or overheat 
condition, and
     Alert the flightcrew to the existence of the fire.
    Most airplanes certified under part 25 have one or two electrical 
equipment bays located in the lower lobe, adjacent to pressure 
regulator/outflow valves or vents. If a fire occurs in an electrical 
equipment bay, any smoke is drawn toward the outflow valves or vents 
and is discharged from the airplane without entering occupied areas. In 
the event of a smoke or fire in one of the electrical equipment bays, 
the procedures to isolate the bay on some airplanes requires the 
flightcrew to use trial and error to determine whether or not the 
source is in a particular electrical equipment bay. However, with this 
approach, the flightcrew does not know where the fire or smoke is 
because it is difficult to identify the source, especially during 
changes of phases of flight (e.g., climbing or descending) or system 
transients (e.g., changes in the airflow from the environmental control 
system).
    This trial-and-error approach may be acceptable for aircraft with 
no more than two electrical equipment bays, both located in the lower 
lobe. In this case, a fire in an electrical equipment bay is in either 
one bay or the other. However, for an aircraft with three or more 
electrical equipment bays, in the time it takes to determine the source 
of smoke, the fire could spread, generating even more smoke and damage.
    In the Model EMB-550 airplane, electrical equipment bays are 
distributed throughout the airplane in the pressurized compartment. 
Section 25.857 requires that cargo compartments have means to prevent 
hazardous quantities of smoke or fire extinguishing agent from 
penetrating into occupied areas of the airplane. However, the 
applicable airworthiness regulations do not address the following:
     Preventing hazardous quantities of smoke or extinguishing 
agent originating from the electrical equipment bays from penetrating 
into occupied areas of the airplane; or
     Installing smoke or fire detectors in electrical equipment 
bays.
    The FAA determined that the Model EMB-550 needs a means to detect 
smoke or fire in each electrical equipment bay that is located in the 
pressurized cabin. This means must indicate in which bay the smoke or 
fire occurs, and ensure that the flightcrew can depower it. For 
situations in which it may be impossible for the flightcrew to shut 
down all the equipment in the bay due to the use of critical or 
essential equipment located in it, Embraer S.A. shall conduct an 
analysis to:
     Specify the criteria for shutting down specific electrical 
equipment in the electrical equipment bay that can be shut down,
     Demonstrate that remaining electrical equipment is 
protected against fire propagation, such as thermal protection, fire 
containment, and other systems as addressed in Advisory Circular 25-16, 
Electrical Fault and Fire Prevention and Protection, dated April 5, 
1991.
    The criteria developed for aircraft designs that incorporate 
distributed electrical/electronic equipment bays are based upon 
existing smoke/fire detection and smoke penetration guidance and 
acceptable past practices. Sections 25.831(b), 25.831(c), 25.831(d), 
and 25.869(a) provide the general requirements that apply to 
electrical/electronic equipment smoke penetration and evacuation. 
Flight tests are conducted to demonstrate compliance; however, the 
amount of smoke generated and flight test conditions have been highly 
variable.
    The special conditions below require that there must be a means to 
detect smoke or fire in each electrical/electronic equipment bay 
located in the pressurized compartment. They also include requirements 
to prevent propagation of hazardous quantities of smoke or fire 
extinguishing agent throughout the passenger cabin.

Applicability

    As discussed above, these special conditions are applicable to the 
Model EMB-550 airplane. Should Embraer S.A. apply at a later date for a 
change to the type certificate to include another model incorporating 
the same novel or unusual design feature, the special conditions would 
apply to that model as well.

Conclusion

    This action affects only certain novel or unusual design features 
on one model of airplanes. It is not a rule of general applicability.

List of Subjects in 14 CFR Part 25

    Aircraft, Aviation safety, Reporting and recordkeeping 
requirements.

    The authority citation for these special conditions is as follows:

    Authority:  49 U.S.C. 106(g), 40113, 44701, 44702, 44704.

The Proposed Special Conditions

    Accordingly, the Federal Aviation Administration (FAA) proposes the 
following special conditions as part of the type certification basis 
for Embraer S.A. Model EMB-550 airplanes.
    1. Requirements to prevent propagation of smoke that originates in 
electrical equipment bays from entering the passenger cabin and flight 
deck:
    a. To prevent such propagation, means to prevent hazardous 
quantities of smoke originating from the electrical equipment bays from 
incapacitating passengers and crew must be demonstrated. The 
demonstrations must include flight tests, and shall be conducted for 
all dispatchable system configurations.
    b. A small quantity of smoke may enter an occupied area only under 
the following conditions:
    i. The smoke enters occupied areas during system transients from 
below the deck or main deck sources. No sustained smoke penetration 
beyond that from environmental control system transients is permitted,
    ii. Penetration of the small quantity of smoke is a dynamic event, 
involving either dissipation or mobility.

[[Page 75073]]

Dissipation is rapid dilution of the smoke by ventilation air. Mobility 
is rapid movement of the smoke into and out of the occupied area. In no 
case should a light haze indicative of stagnant airflow form, as this 
indicates that the ventilation system is failing to meet the 
requirements of 14 CFR 25.831,
    iii. The smoke from a source below the main deck must not rise 
above armrest height on the main deck, and
    iv. The smoke from a source in the main deck must dissipate rapidly 
via dilution with fresh air and be evacuated from the airplane. The 
Airplane Flight Manual (AFM) must include procedures to evacuate smoke 
from the occupied areas. To demonstrate that the quantity of smoke is 
small, a flight test must be conducted which simulates the emergency 
procedures used in the event of a fire during flight, including the use 
of VMO/MMO descent profiles and a simulated 
landing, if such conditions are specified in the emergency procedure.
    2. Requirement for smoke or fire detection in electrical/electronic 
equipment bays: A smoke or fire detection system compliant with 
Sec. Sec.  25.855(a), (b), (c), and (d); and Sec.  25.858 must be 
provided for each electrical/electronic equipment bay in the 
pressurized cabin. Each system must provide a visual indication to the 
flight deck within one minute after the start of a fire. Airplane 
flight tests must be conducted to show compliance with these 
requirements, and the performance of the detectors must be shown in 
accordance with Advisory Circular 25-9A, Smoke Detection, Penetration, 
and Evacuation Tests and Related Flight Manual Emergency Procedures, or 
other means acceptable to the FAA.
    3. Requirement for AFM procedures safety analysis: It shall be 
demonstrated that the AFM procedures to shut down electrical/electronic 
equipment bays, or part of them, in case of smoke/fire detection, do 
not compromise the safe operation of the aircraft. If a procedure 
requests to shut down only part of the equipment, the remaining 
equipment shall be incorporated with safety precautions against fire 
propagation.

    Issued in Renton, Washington, on December 13, 2012.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2012-30493 Filed 12-18-12; 8:45 am]
BILLING CODE 4910-13-P