Document ID: FAA-2012-1301-0001
Agency: faa
Document Type: Proposed Rule
Title: Special Conditions: Embraer S.A., Model EMB-550 Airplane, Dive Speed Definition with Speed Protection System
Posted Date: 2013-01-24T05:00Z

[Federal Register Volume 78, Number 16 (Thursday, January 24, 2013)]
[Proposed Rules]
[Pages 5146-5148]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2013-01457]

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 Proposed Rules
                                                 Federal Register
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 This section of the FEDERAL REGISTER contains notices to the public of 
 the proposed issuance of rules and regulations. The purpose of these 
 notices is to give interested persons an opportunity to participate in 
 the rule making prior to the adoption of the final rules.
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  Federal Register / Vol. 78, No. 16 / Thursday, January 24, 2013 / 
Proposed Rules  

[[Page 5146]]

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 25

[Docket No. FAA-2012-1301; Notice No. 25-12-18-SC]

Special Conditions: Embraer S.A., Model EMB-550 Airplane, Dive 
Speed Definition With Speed Protection System

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed special conditions.

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SUMMARY: This action proposes special conditions for the Embraer S.A. 
Model EMB-550 airplane. This airplane will have a novel or unusual 
design feature when compared to the state of technology envisioned in 
the airworthiness standards for transport category airplanes. These 
design features include a high-speed protection system. 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 March 11, 2013.

ADDRESSES: Send comments identified by docket number FAA-2012-1301 
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 com plete 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: Todd Martin, FAA, Airframe and Cabin 
Safety Branch, ANM-115, Transport Airplane Directorate, Aircraft 
Certification Service, 1601 Lind Avenue SW., Renton, Washington 98057-
3356; telephone 425-227-1178; 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 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, ailerons and rudder, controlled by the pilot or 
copilot sidestick.
    The Model EMB-550 airplane incorporates a high-speed protection 
system in the airplane's flight control laws. The airplane's high-speed 
protection system limits nose-down pilot authority by adding automatic 
control inputs at threshold speeds above VMO/MMO, 
which influence the results of the traditional recovery maneuvers 
required in Title 14, Code of Federal Regulations (14 CFR) 
25.335(b)(1). This speed protection system was not envisioned when 
Sec.  25.335 was promulgated.

Type Certification Basis

    Under the provisions of 14 CFR part 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 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

[[Page 5147]]

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 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: a high-speed protection system that limits 
nose-down pilot authority at speeds above VMO/
MMO. This system prevents the airplane from performing the 
maneuver required under Sec.  25.335(b)(1).

Discussion

    Section 25.335(b)(1) is a dive speed condition that was originally 
adopted in part 4b of the Civil Air Regulations in order to provide an 
acceptable speed margin between design cruise speed and design dive 
speed. Flutter clearance design speeds and airframe design loads are 
impacted by the design dive speed. While the initial condition for the 
upset specified in the rule is 1g level flight, protection is afforded 
for other inadvertent overspeed conditions as well. Section 
25.335(b)(1) is intended as a conservative enveloping condition for 
potential overspeed conditions, including non-symmetric conditions. To 
ensure that potential overspeed conditions are covered, the applicant 
should demonstrate that the dive speed will not be exceeded in 
inadvertent, or gust-induced, upsets resulting in initiation of the 
dive from non-symmetric attitudes; or that the airplane is protected by 
the flight control laws from getting into non-symmetric upset 
conditions. The applicant should conduct a demonstration that includes 
a comprehensive set of conditions, as described in the special 
conditions.
    These special conditions are proposed in lieu of Sec.  
25.335(b)(1). Section 25.335(b)(2), which also addresses the design 
dive speed, is applied separately. Advisory Circular (AC) 25.335-1A, 
Design Dive Speed, dated September 29, 2000, provides an acceptable 
means of compliance to Sec.  25.335(b)(2)).
    Special conditions are necessary to address the high-speed 
protection system on the Model EMB-550. The proposed special conditions 
identify various symmetric and non-symmetric maneuvers that will ensure 
that an appropriate design dive speed, VD/MD, is 
established.
    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.
    This special condition is proposed in lieu of 14 CFR 25.335(b)(1). 
Section 25.335(b)(2), also addresses the design dive speed, but it is 
applied separately. Advisory Circular (AC) 25.335-1A, Design Dive 
Speed, dated September 29, 2000, provides an acceptable means of 
compliance to Sec.  25.335(b)(2).

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. Dive Speed Definition with Speed Protection System.
    (1) In lieu of the requirements of 14 CFR 25.335(b)(1), if the 
flight control system includes functions that act automatically to 
initiate recovery before the end of the 20-second period specified in 
Sec.  25.335(b)(1), VD/MD must be determined from 
the greater of the speeds resulting from the conditions (a) and (b) 
below. The speed increase occurring in these maneuvers may be 
calculated if reliable or conservative aerodynamic data are used.
    (a) From an initial condition of stabilized flight at 
VC/MC, the airplane is upset and takes a new 
flight path 7.5 degrees below the initial path. Control application, up 
to full authority, is made to try and maintain this new flight path. 
Twenty seconds after initiating the upset, manual recovery is made at a 
load factor of 1.5g (0.5 acceleration increment), or such greater load 
factor that is automatically applied by the system with the pilot's 
pitch control neutral. Power, as specified in Sec.  25.175(b)(1)(iv), 
is assumed until recovery is initiated, at which time power reduction 
and pilot-controlled drag devices may be used.
    (b) From a speed below VC/MC, with power to 
maintain stabilized level flight at this speed, the airplane is upset 
so as to accelerate through VC/MC at a flight 
path 15 degrees below the initial path (or at the steepest nose down 
attitude that the system will permit with full control authority if 
less than 15 degrees). The pilot's controls may be in the neutral 
position after reaching VC/MC and before recovery 
is initiated. Recovery may be initiated three seconds after operation 
of the high-speed warning system by application of a load of 1.5g (0.5 
acceleration increment), or such greater load factor that is 
automatically applied by the system with the pilot's pitch control 
neutral. Power may be reduced simultaneously. All other means of 
decelerating the airplane, the use of which is authorized up to the 
highest speed reached in the maneuver, may be used. The interval 
between successive pilot actions must not be less than one second.
    (2) The applicant must also demonstrate that the speed margin, 
established as above, will not be exceeded in inadvertent, or gust-
induced, upsets resulting in initiation of the dive from non-symmetric 
attitudes, unless the airplane is protected by the flight control laws 
from getting into non-symmetric upset conditions. The upset maneuvers 
described in paragraphs 32.c(3)(a) and 32.c(3)(c) of AC 25-7B, Flight 
Test Guide for Certification of Transport Category Airplanes, Change 1, 
dated December 7, 2011, may be used to comply with this requirement.
    (3) Any failure of the high-speed protection system that would 
result in an airspeed exceeding those determined by paragraphs (1) and 
(2) must be less than 10-5 per flight hour.
    (4) Failures of the system must be annunciated to the pilots. 
Flight manual instructions must be provided that reduce the maximum 
operating speeds VMO/MMO. The operating speed 
must be reduced to a value that maintains a speed margin between 
VMO/MMO and VD/MD that is 
consistent with showing compliance with Sec.  25.335(b) without the 
benefit of the high-speed protection system.
    (5) Dispatch of the airplane with the high-speed protection system

[[Page 5148]]

inoperative could be allowed under an approved minimum equipment list 
(MEL) that would require flight manual instructions to indicate reduced 
maximum operating speeds, as described in paragraph (4). In addition, 
the flightdeck display of the reduced operating speeds, as well as the 
overspeed warning for exceeding those speeds, must be equivalent to 
that of the normal airplane with the high-speed protection system 
operative. Also, it must be shown that no additional hazards are 
introduced with the high-speed protection system inoperative.

    Issued in Renton, Washington, on December 10, 2012.
Michael Kaszycki,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2013-01457 Filed 1-23-13; 8:45 am]
BILLING CODE 4910-13-P