18148 Federal Register / Vol. 72, No. 69 / Wednesday, April 11, 2007 / Proposed Rules 

representative engine in accordance 

with paragraph (a) or (b) of this section, 

as applicable, without evidence of 

failure or malfunction. 

(a) Fixed-pitch and ground adjustablepitch propellers must be subjected to 

one of the following tests: 

(1) A 50-hour flight test in level flight 

or in climb. The propeller must be 

operated at takeoff power and rated 

rotational speed during at least five 

hours of this flight test, and at not less 

than 90 percent of the rated rotational 

speed for the remainder of the 50 hours. 

(2) A 50-hour ground test at takeoff 

power and rated rotational speed. 

(b) Variable-pitch propellers must be 

subjected to one of the following tests: 

(1) A 110-hour endurance test that 

must include the following conditions: 

(i) Five hours at takeoff power and 

rotational speed and thirty 10-minute 

cycles composed of: 

(A) Acceleration from idle, 

(B) Five minutes at takeoff power and 

rotational speed, 

(C) Deceleration, and 

(D) Five minutes at idle. 

(ii) Fifty hours at maximum 

continuous power and rotational speed, 

(iii) Fifty hours, consisting of ten 5- 

hour cycles composed of: 

(A) Five accelerations and 

decelerations between idle, takeoff 

power and rotational speed; 

(B) Four and one-half hours at 

approximately even incremental 

conditions from idle up to, but not 

including, maximum continuous power 

and rotational speed; and 

(C) Thirty minutes at idle. 

(2) The operation of the propeller 

throughout the engine endurance tests 

prescribed in part 33 of this chapter. 

(c) An analysis based on tests of 

propellers of similar design may be used 

in place of the tests of § 35.39(a) and (b). 

32. Add § 35.40 to read as follows: 

§ 35.40 Functional test. 

The variable-pitch propeller system 

must be subjected to the applicable 

functional tests of this section. The 

same propeller system used in the 

endurance test (§ 35.39) must be used in 

the functional tests and must be driven 

by a representative engine on a test 

stand or on an airplane. The propeller 

must complete these tests without 

evidence of failure or malfunction. This 

test may be combined with the 

endurance test for accumulation of 

cycles. 

(a) Manually-controllable propellers. 

Five hundred representative flight 

cycles must be made across the range of 

pitch and rotational speed. 

(b) Governing propellers. Fifteen 

hundred complete cycles must be made 

across the range of pitch and rotational 

speed. 

(c) Feathering propellers. Fifty cycles 

of feather and unfeather operation must 

be made. 

(d) Reversible-pitch propellers. Two 

hundred complete cycles of control 

must be made from lowest normal pitch 

to maximum reverse pitch. During each 

cycle, the propeller must be run for 30 

seconds at the maximum power and 

rotational speed selected by the 

applicant for maximum reverse pitch. 

(e) An analysis based on tests of 

propellers of similar design may be used 

in place of the tests of § 35.40. 

33. Revise §§ 35.41, 35.42, and 35.43 

to read as follows: 

§ 35.41 Overspeed and overtorque. 

(a) When the applicant seeks approval 

of a transient maximum propeller 

overspeed, the applicant must 

demonstrate that the propeller is 

capable of further operation without 

maintenance action at the maximum 

propeller overspeed condition. This 

may be accomplished by: 

(1) Performance of 20 runs, each of 30 

seconds duration, at the maximum 

propeller overspeed condition; or 

(2) Analysis based on test or service 

experience. 

(b) When the applicant seeks approval 

of a transient maximum propeller 

overtorque, the applicant must 

demonstrate that the propeller is 

capable of further operation without 

maintenance action at the maximum 

propeller overtorque condition. This 

may be accomplished by: 

(1) Performance of 20 runs, each of 30 

seconds duration, at the maximum 

propeller overtorque condition; or 

(2) Analysis based on test or service 

experience. 

§ 35.42 Components of the propeller 

control system. 

The applicant must demonstrate by 

tests, analysis based on tests, or service 

experience on similar components, that 

each propeller blade pitch control 

system component, including governors, 

pitch change assemblies, pitch locks, 

mechanical stops, and feathering system 

components, can withstand cyclic 

operation that simulates the normal load 

and pitch change travel to which the 

component would be subjected during 

the initially declared overhaul period or 

during a minimum of 1000 hours of 

typical operation in service. 

§ 35.43 Propeller hydraulic components. 

Applicants must show that propeller 

components that contain hydraulic 

pressure and whose structural failure or 

leakage from a structural failure could 

cause a hazardous propeller effect 

demonstrate structural integrity by: 

(a) A proof pressure test to 1.5 times 

the maximum operating pressure for one 

minute without permanent deformation 

or leakage that would prevent 

performance of the intended function. 

(b) A burst pressure test to 2.0 times 

the maximum operating pressure for one 

minute without failure. Leakage is 

permitted and seals may be excluded 

from the test. 

§ 35.45 [Removed] 

34. Remove and reserve § 35.45. 

§ 35.47 [Removed] 

35. Remove and reserve § 35.47. 

Issued in Washington, DC, on March 26, 

2007. 

John J. Hickey, 

Director, Aircraft Certification Service. 

[FR Doc. E7–6193 Filed 4–10–07; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 33 

[Docket No. FAA–2007–27311; Notice No. 

07–03] 

RIN 2120–AI94 

Airworthiness Standards; Engine 

Control System Requirements 

AGENCY: Federal Aviation 

Administration, DOT. 

ACTION: Notice of proposed rulemaking 

(NPRM). 

SUMMARY: The Federal Aviation 

Administration (FAA) is proposing to 

revise type certification standards for 

aircraft engine control systems. These 

proposed changes reflect current 

practices and harmonize FAA standards 

with those recently adopted by the 

European Aviation Safety Agency 

(EASA). These proposed changes would 

establish uniform standards for all 

engine control systems for aircraft 

engines certificated by both U.S. and 

European countries and would simplify 

airworthiness approvals for import and 

export. 

DATES: Send your comments on or 

before July 10, 2007. 

ADDRESSES: You may send comments 

identified by Docket Number [FAA–

2007–27311] using any of the following 

methods: 

• DOT Docket Web site: Go to 

http://dms.dot.gov and follow the 

instructions for sending your comments 

electronically. 


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Federal Register / Vol. 72, No. 69 / Wednesday, April 11, 2007 / Proposed Rules 18149 

• Government-wide rulemaking Web 

site: Go to http://www.regulations.gov 

and follow the instructions for sending 

your comments electronically. 

• Mail: Docket Management Facility; 

U.S. Department of Transportation, 400 

Seventh Street, SW., Nassif Building, 

Room PL–401, Washington, DC 20590–

0001. 

• Fax: 1–202–493–2251. 

• Hand Delivery: Room PL–401 on 

the plaza level of the Nassif Building, 

400 Seventh Street, SW., Washington, 

DC, between 9 a.m. and 5 p.m., Monday 

through Friday, except Federal holidays. 

For more information on the 

rulemaking process, see the 

SUPPLEMENTARY INFORMATION section of 

this document. 

Privacy: We will post all comments 

we receive, without change, to http:// 

dms.dot.gov, including any personal 

information you provide. For more 

information, see the Privacy Act 

discussion in the SUPPLEMENTARY

INFORMATION section of this document. 

Docket: To read background 

documents or comments received, go to 

http://dms.dot.gov at any time or to 

Room PL–401 on the plaza level of the 

Nassif Building, 400 Seventh Street, 

SW., Washington, DC, between 9 a.m. 

and 5 p.m., Monday through Friday, 

except Federal holidays. 

FOR FURTHER INFORMATION CONTACT: Gary 

Horan, Engine and Propeller Directorate 

Standards Staff, ANE–111, Federal 

Aviation Administration, 12 New 

England Executive Park, Burlington, 

Massachusetts 01803–5299; telephone 

(781) 238–7164, fax (781) 238–7199, email gary.horan@faa.gov. 

SUPPLEMENTARY INFORMATION: 

Comments Invited 

The FAA invites interested persons 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. We ask that you send 

us two copies of written comments. 

We will file in the docket all 

comments we receive, as well as a 

report summarizing each substantive 

public contact with FAA personnel 

concerning this proposed rulemaking. 

The docket is available for public 

inspection before and after the comment 

closing date. If you wish to review the 

docket in person, go to the address in 

the ADDRESSES section of this preamble 

between 9 a.m. and 5 p.m., Monday 

through Friday, except Federal holidays. 

You may also review the docket using 

the Internet at the Web address in the 

ADDRESSES section. 

Privacy Act: Using the search function 

of our docket Web site, anyone can find 

and read the comments received into 

any of our dockets, including the name 

of the individual sending the comment 

(or signing the comment on behalf of an 

association, business, labor union, etc.). 

You may review DOT’s complete 

Privacy Act Statement in the Federal 

Register published on April 11, 2000 

(65 FR 19477–78) or you may visit 

http://dms.dot.gov. 

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 late if it is possible to do so 

without incurring expense or delay. We 

may change this proposal in light of the 

comments we receive. 

If you want the FAA to acknowledge 

receipt of your comments on this 

proposal, include with your comments 

a pre-addressed, stamped postcard on 

which the docket number appears. We 

will stamp the date on the postcard and 

mail it to you. 

Availability of Rulemaking Documents 

You can get an electronic copy using 

the Internet by: 

(1) Searching the Department of 

Transportation’s electronic Docket 

Management System (DMS) Web page 

(http://dms.dot.gov/search); 

(2) Visiting the FAA’s Regulations and 

Policies Web page at http:// 

www.faa.gov/regulations_policies/; or 

(3) Accessing the Government 

Printing Office’s Web page at http:// 

www.gpoaccess.gov/fr/index.html. 

You can also get a copy by sending a 

request to the Federal Aviation 

Administration, Office of Rulemaking, 

ARM–1, 800 Independence Avenue, 

SW., Washington, DC 20591, or by 

calling (202) 267–9680. Make sure to 

identify the docket number, notice 

number, or amendment number of this 

rulemaking. 

Background 

U.S. and European aircraft engine 

regulations differ in several areas 

including engine controls. 

Harmonization of these differences 

benefits industry and regulators because 

of the lower costs associated with one 

set of engine control regulations. 

The FAA, in cooperation with the 

Joint Aviation Authorities (JAA), the 

European rulemaking authority before 

EASA, established an international 

engine certification study group to 

compare part 33 with the Joint Aviation 

Requirements—Engines (JAR–E), the 

European requirements for engines. As 

a follow-on, the Aviation Rulemaking 

Advisory Committee, through its Engine 

Harmonization Working Group (EHWG), 

looked at harmonizing the engine 

control requirements of part 33 and the 

JAR–E. 

In response to EHWG 

recommendations, the JAA published a 

Notice of Proposed Amendment (NPA), 

NPA–E–33 Rev 0, on April 20, 2001. 

JAA’s proposed amendment contained 

rules and advisory material almost 

identical to FAA’s proposed part 33 

changes. Some commenters to this NPA 

objected that the reliability of aircraftsupplied electrical power should be 

considered when determining the 

required degree of protection against 

failure. Because of these comments, the 

JAA updated its rulemaking in NPA–E–

33 Rev 1. The FAA and the JAA 

subsequently agreed that the reliability 

and quality of aircraft-supplied power 

should be a factor in considering the 

approval of the engine design. This 

NPRM reflects this agreement between 

FAA and the JAA. EASA has adopted 

this agreement as CS–E (Certification 

Specifications for Engines) 50(h). 

Section-by-Section Discussion of the 

Proposals 

Section 33.5 

We propose adding new paragraphs 

(a)(4), (a)(5), (a)(6) and (b)(4) to § 33.5 to 

require applicants to include additional 

installation information in their 

instructions for installation. The 

requirements in proposed paragraphs 

(a)(4), (a)(5) and (b)(4) are currently 

prescribed under § 33.28(a) as part of 

the control system description. This 

proposal places these requirements in 

sections consistent with their intended 

purpose. 

Our proposed § 33.5(a)(6) would 

require that installation instructions list 

the instruments necessary for 

satisfactory control of the engine. It 

would also require that the limits of 

accuracy and transient response 

required for satisfactory engine 

operation be identified so that the 

suitability of the instruments as 

installed can be assessed. Part 33 does 

not require similar installation 

information. We would harmonize 

§§ 33.5(a)(4), (a)(5) and (b)(4) with CS–

E 20(d), CS–E 30(b), and CS–E 20(d), 

respectively. Adding § 33.5(a)(6) would 

harmonize with CS–E 60(b). 

Section 33.7 

We propose adding a new paragraph 

(d) to this section. This paragraph 


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would require that the overall limits of 

accuracy of the engine control system 

and the necessary instruments, as 

defined in § 33.5(a)(6), be considered 

when determining engine performance 

and operating limitations. Paragraph (d) 

would harmonize with CS–E 40(g). 

Section 33.27 

We propose a new § 33.27(b) that 

prescribes requirements for methods, 

other than engine control methods, for 

protecting rotor structural integrity 

during overspeed conditions. These 

methods would include protection 

methods, such as blade shedding, 

currently regulated under the CS–E but 

not identified under part 33. 

Section 33.28 

We propose changing the title of 

§ 33.28 and the content of its 

paragraphs. The title would be changed 

from ‘‘Electrical and electronic engine 

control systems’’ to ‘‘Engine control 

systems.’’ Currently, § 33.28 applies 

only to electrical and electronic engine 

control systems, while CS–E 50 and 

associated requirements apply to all 

types of engine control systems, 

including hydromechanical and 

reciprocating engine controls. The new 

title reflects the proposed revisions to 

the section which, to harmonize with 

EASA specifications, would change the 

scope of the proposed rule to include all 

types of engine control systems and 

devices under § 33.28. 

Section 33.28(a) 

Our proposed § 33.28(a) would be 

titled ‘‘Applicability’’ and would clarify 

the systems or devices that are subject 

to § 33.28 requirements. 

Section 33.28(b) 

We propose replacing existing 

§ 33.28(b) with new § 33.28(b), 

‘‘Validation,’’ which prescribes 

requirements for engine control system 

validation. The new § 33.28(b) consists 

of new paragraphs (b)(1) and (b)(2). 

Our proposed § 33.28(b)(1) requires 

that applicants demonstrate that their 

engine control system performs its 

intended function in the declared 

operating conditions, including 

environmental conditions and flight 

envelope. Part 33 generally requires this 

showing, but does so nonspecifically. 

This new specific requirement will 

clarify the regulation. 

The proposed § 33.28(b)(1) requires 

that the engine control system comply 

with §§ 33.51, 33.65, and 33.73, as 

appropriate, under all likely system 

inputs and allowable engine power or 

thrust demands. It also requires that the 

engine control system allow engine 

power and thrust modulation with 

adequate sensitivity over the declared 

range of engine operating conditions. 

The engine control system also must not 

create unacceptable power or thrust 

oscillations. 

Proposed § 33.28(b)(1) would 

harmonize the sections in part 33 that 

address engine performance and 

operability requirements with similar 

requirements in CS–E 50. 

Our proposed § 33.28(b)(2) revises 

requirements located in the existing 

§ 33.28(d). Proposed § 33.28(b)(2) would 

clarify environmental testing 

requirements, including those for High 

Intensity Radiated Fields (HIRF), 

lightning, and electromagnetic 

interference (EMI) for the engine control 

system. 

The environmental testing 

requirements that are part of the 

proposed § 33.28(b) set the installation 

limitations. Those limitations are 

incorporated into the instructions in 

accordance with § 33.5(b)(4). 

Section 33.28(c) 

We propose to revise § 33.28(c) to 

clarify the requirements for control 

transitions when fault accommodation 

is implemented through alternate 

modes, channel changes, or changes 

from primary to back-up systems. 

Proposed § 33.28(c), titled ‘‘Control 

transitions,’’ will clarify the need for 

crew notification if crew action is 

required as part of fault accommodation. 

Section 33.28(d) 

Our proposed § 33.28(d) would 

consist of revised control system failure 

requirements formerly located in 

§ 33.28(c). Proposed § 33.28(d), titled 

‘‘Engine control system failures,’’ would 

consist of four paragraphs: § 33.28(d)(1) 

would address integrity requirements, 

such as Loss of Thrust Control (LOTC) 

requirements consistent with the 

intended application; § 33.28(d)(2) 

would require accommodation of single 

failures with respect to LOTC/LOPC 

(Loss of Power Control) events; 

§ 33.28(d)(3) would clarify requirements 

for single failures of electrical or 

electronic components; and 

§ 33.28(d)(4) would add requirements 

for foreseeable failures or malfunctions 

in the intended aircraft installation such 

as fire and overheat (i.e., local events). 

We considered using the phrase 

‘‘essentially single fault tolerant’’ in 

proposed paragraph (d)(2) as the 

standard for measuring the compliance 

of an applicant’s engine control system. 

We have had extensive discussions with 

industry about the meaning of 

‘‘essentially single fault tolerant.’’

However, in reviewing the meaning of 

‘‘essentially,’’ we decided that this term 

introduces sufficient ambiguity so that 

the phrase could not serve as the basis 

for an enforceable standard. We chose, 

therefore, to remove ‘‘essentially’’ and to 

reserve to the Administrator the right to 

define what is meant by ‘‘single fault 

tolerant.’’ We are preparing an advisory 

circular to offer guidance regarding 

what we mean by ‘‘single fault tolerant’’

as used in the regulation. 

Section 33.28(e) 

Our proposed § 33.28(e), titled 

‘‘System safety assessment,’’ would 

require a System Safety Assessment 

(SSA) for the engine control system. The 

SSA would identify faults or failures 

that would have harmful effects on the 

engine. Proposed § 33.28(e) harmonizes 

with CS–E 50(d). 

Section 33.28(f) 

Our proposed § 33.28(f), titled 

‘‘Protection systems,’’ requires 

protective functions that preserve rotor 

integrity. Proposed § 33.28(f)(1) would 

include the protection requirements of 

the existing § 33.27(b). Proposed 

§ 33.28(f)(2) adds requirements for 

testing the protection function for 

availability. Proposed § 33.28(f)(3) 

establishes requirements for overspeed 

protection systems implemented 

through hydromechanical or mechanical 

means. Proposed § 33.28(f) harmonizes 

with CS–E 50(e). 

Section 33.28(g) 

Our proposed § 32.28(g), titled 

‘‘Software,’’ would consist of the 

software requirements for the engine 

control system currently prescribed 

under § 33.28(e). We are proposing to 

revise § 33.28(g) to require that software 

be consistent with the criticality of 

performed functions. Proposed 

§ 33.28(g) harmonizes with CS–E 50(f). 

Section 33.28(h) 

Our proposed § 33.28(h), titled 

‘‘Aircraft-supplied data,’’ clarifies 

requirements related to failure of 

aircraft-supplied data. The revision 

consists of two new paragraphs that 

prescribe requirements for single 

failures leading to loss, interruption, or 

corruption of aircraft-supplied data or 

data shared between engines. We 

propose to modify the current FAA 

requirement for fault accommodation 

for loss of all aircraft-supplied data to 

require detection and accommodation 

for single failures leading to loss, 

interruption, or corruption of aircraftsupplied data. This accommodation 

must not result in an unacceptable 

change in thrust or power or an 

unacceptable change in engine 


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operating and starting characteristics. 

Proposed § 33.28(h) harmonizes with 

CS–E 50(g). 

Section 33.28(i) 

Our proposed § 33.28(i), titled 

‘‘Aircraft-supplied electrical power,’’

clarifies requirements for the response 

of the engine control system to loss or 

interruption of electrical power 

supplied from the aircraft. Proposed 

§ 33.28(i) would apply to all electrical 

power supplied to the engine control 

system, including that supplied from 

the aircraft power system and from the 

dedicated power source, if required. 

We propose to add requirements to 

§ 33.28(i) that represent current industry 

standard practices but are not in part 33. 

These include a requirement that the 

applicant define in the instructions for 

installation: 

1. The power characteristics of any 

power supplied from the aircraft to the 

engine control system; and 

2. The engine control and engine 

responses to low voltage transients 

outside the declared power supply 

voltage limitations. 

This action proposes an additional 

requirement for a dedicated power 

source for the control system to provide 

sufficient capacity to power the 

functions provided by the control 

system below idle, such as for the autorelight function. 

With the change in scope of this 

proposal from electronic engine controls 

to engine controls, it is not our intent 

that all electrically powered engine 

functions be under the § 33.28(i) 

requirement for a dedicated power 

source. The loss of some control 

functions traditionally dependent on 

aircraft-supplied power continues to be 

acceptable. The use of conventional 

aircraft-supplied power for these 

traditional functions has been 

acceptable as they, in general, do not 

affect the safe operation of the engine. 

Examples include: 

• Functions without safety 

significance that are primarily 

performance enhancement functions 

• Engine start and ignition 

• Thrust reverser deployment 

• Anti-icing (engine probe heat) 

• Fuel shut-off 

Our proposed § 33.28(i) harmonizes 

with CS–E 50(h). 

Section 33.28(j) 

We propose adding a new § 33.28(j), 

titled ‘‘Air pressure signal,’’ that would 

add safety requirements for air pressure 

signals in the engine control system. It 

will require that applicants take design 

precautions to minimize system 

malfunction from ingress of foreign 

matter or blockage of the signal lines by 

foreign matter or ice. Our proposed 

§ 33.28(j) harmonizes with CS–E 50(i). 

Section 33.28(k) 

Our proposed § 33.28(k), ‘‘Automatic 

availability and control of engine power 

for 30-second OEI rating,’’ prescribes 

requirements for engines with OneEngine-Inoperative (OEI) capability. 

This proposal, formerly located in 

§ 33.67(d), prescribes a control function 

that more properly is located in the 

‘‘Engine control systems’’ section. We 

propose moving the contents of 

§ 33.67(d) to 33.28(k). Our proposed 

§ 33.28(k) harmonizes with CS–E 50(j). 

Section 33.28(l) 

Our proposed § 33.28(l), titled 

‘‘Engine shutdown means,’’ requires 

that the engine control system provide 

a rapid means of shutting down the 

engine. Proposed § 33.28(l) harmonizes 

with CS–E 50(k). 

Section 33.28(m) 

Our proposed § 33.28(m), titled 

‘‘Programmable logic devices,’’ adds 

safety requirements for programmable 

logic devices (PLD) that include 

Application-Specific Integrated Circuits 

and programmable gate arrays. We 

decided to propose new PLD 

requirements separate from software 

requirements, although the 

requirements are similar, because PLD’s 

combine software and complex 

hardware. The proposed rule would 

require that development of the devices 

and associated encoded logic used in 

their design and implementation be at a 

level equal to the hazard level of the 

functions performed via the devices. 

Proposed § 33.28(m) harmonizes with 

CS–E 50(f). 

Section 33.29 

We propose revising § 33.29 by 

adding new paragraphs (e) through (h) 

to harmonize with CS–E 60, Provision 

for Instruments. 

The new § 33.29(e) would require that 

applicants provide instrumentation 

necessary to ensure engine operation in 

compliance with the engine operating 

limitations. When instrumentation is 

necessary for compliance with the 

engine requirements, applicants must 

specify the instrumentation in the 

instructions for installation and include 

the instrumentation as part of the engine 

type design. The proposed § 33.29(e) 

harmonizes with CS–E 60(a). 

The existing § 33.29(a) requirement 

addresses the prevention of incorrect 

connections of instruments only. 

Proposed § 33.29(f) would require that 

applicants provide a means to minimize 

the possibility of incorrect fitting of 

instruments, sensors and connectors. 

Proposed § 33.29(f) harmonizes with 

CS–E 110(e). 

Currently, part 33 does not address 

requirements for sensors and associated 

wiring and signal conditioning 

segregation. Proposed § 33.29(g) would 

reduce the probability of faults 

propagating from the instrumentation 

and monitoring functions to the control 

functions, or vice versa, by prescribing 

that the probability of propagation of 

faults be consistent with the criticality 

of the function performed. Proposed 

§ 33.29(g) harmonizes with CS–E 60(c). 

Our proposed § 33.29(h) would add 

new requirements for instrumentation 

that enables the flight crew to monitor 

the functioning of the turbine case 

cooling system. Proposed § 33.29(h) 

harmonizes with CS–E 60(e). 

Section 33.53 

We propose revising the title of 

§ 33.53 from ‘‘Engine component tests,’’

to ‘‘Engine system and component 

tests.’’ The revised title would better 

identify reciprocating engine control 

system tests that may be conducted 

under this paragraph. Proposed 

§ 33.53(a) provides for systems tests if 

required. 

Section 33.91 

We propose changing the title of 

§ 33.91 from ‘‘Engine component tests’’

to ‘‘Engine system and component 

tests.’’ The revised title would better 

identify engine control system tests, for 

example, system validation testing, that 

may be required under this paragraph. 

Our proposed § 33.91(a) would provide 

for systems tests if required. 

Rulemaking Analyses and Notices 

Authority for This Rulemaking 

Title 49 of the United States Code 

specifies the FAA’s authority to issue 

rules on aviation safety. Subtitle I, 

Section 106, describes the authority of 

the FAA Administrator. Subtitle VII, 

Aviation Programs, describes in more 

detail the scope of the Agency’s 

authority. 

We are issuing this rulemaking under 

the authority described in Subtitle VII, 

Part A, Subpart III, Section 44701, 

‘‘General requirements.’’ Under that 

section, Congress charges the FAA with 

promoting safe flight of civil aircraft in 

air commerce by prescribing regulations 

for practices, methods, and procedures 

the Administrator finds necessary for 

safety in air commerce, including 

minimum safety standards for aircraft 

engines. This proposed rule is within 

the scope of that authority because it 


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updates existing regulations for aircraft 

engine control systems. 

Paperwork Reduction Act 

The Paperwork Reduction Act of 1995 

(44 U.S.C. 3507(d)) requires that the 

FAA consider the impact of paperwork 

and other information collection 

burdens imposed on the public. We 

determined that this proposed rule does 

not impose any new information 

collection requirements. 

International Compatibility 

In keeping with U.S. obligations 

under the Convention on International 

Civil Aviation, we comply with 

International Civil Aviation 

Organization (ICAO) Standards and 

Recommended Practices to the 

maximum extent practicable. We 

determined that ICAO has no Standards 

or Recommended Practices that 

correspond to these proposed 

regulations. 

Economic Assessment, Regulatory 

Flexibility Determination, Trade Impact 

Assessment, and Unfunded Mandates 

Assessment 

Changes to Federal regulations must 

undergo several economic analyses. 

First, Executive Order 12866 directs that 

each Federal agency propose or adopt a 

regulation only upon a determination 

that the benefits of the intended 

regulation justify its costs. Second, the 

Regulatory Flexibility Act of 1980 (Pub. 

L. 96–354) requires agencies to analyze 

the economic impact of regulatory 

changes on small entities. Third, the 

Trade Agreements Act (Pub. L. 96–39) 

prohibits agencies from setting 

standards that create unnecessary 

obstacles to the foreign commerce of the 

United States. In developing U.S. 

standards, this Trade Act also requires 

agencies to consider international 

standards and, where appropriate, use 

them as the basis of U.S. standards. 

Fourth, the Unfunded Mandates Reform 

Act of 1995 (Pub. L. 104–4) requires 

agencies to prepare a written assessment 

of the costs, benefits, and other effects 

of proposed or final rules that include 

a Federal mandate likely to result in the 

expenditure by State, local, or tribal 

governments, in the aggregate, or by 

private sector, of $100 million or more 

annually (adjusted for inflation with 

base year of 1995). This portion of the 

preamble summarizes the FAA’s 

analysis of the economic impacts of this 

proposed rule. 

Department of Transportation Order 

DOT 2100.5 prescribes policies and 

procedures for simplification, analysis, 

and review of regulations. If the 

expected cost impact is so minimal that 

a proposed or final rule does not 

warrant a full evaluation, this order 

permits that a statement to that effect, 

and the basis for it, be included in the 

preamble if a full regulatory evaluation 

of the cost and benefits is not prepared. 

Such a determination has been made for 

this proposed rule. The reasoning for 

this determination follows. 

The proposed rule reflects current 

practices and harmonizes FAA 

airworthiness standards for aircraft 

engine control systems with similar 

requirements recently adopted by 

EASA. These proposed changes to 

engine control system requirements 

would establish uniform standards for 

all engine control systems for aircraft 

engines certificated by both U.S. and 

European countries and would simplify 

airworthiness approvals for import and 

export. Similar international 

requirements would reduce duplicative 

testing which would reduce certification 

costs. 

An engine control system is any 

system or device that controls, limits, or 

monitors engine operation and is 

necessary for the continued 

airworthiness of the engine. This 

implies consideration of all control 

system components including the 

electronic control unit(s), fuel metering 

unit(s), variable-geometry actuators, 

cables, wires, and sensors. 

An engine control system may be 

composed of several subsystems which 

can include: (1) Fuel control, (2) spark 

control, (3) turbocharger wastegate 

control, (4) throttle control, and (5) 

propeller governor. A turbine FADEC 

(Full Authority Digital Engine Control) 

system typically controls the fuel, the 

variable pitch vanes, the engine 

operability bleeds, the temperature 

management system and, most recently, 

the ignition and other starting elements. 

A reciprocating engine could be 

considered to have a FADEC system if 

any of the subsystems are controlled 

electronically over their full range of 

operation. 

The proposed regulation covers the 

main engine control system as well as 

the protection systems, for example, 

overspeed, over-torque, or overtemperature. Engine monitoring systems 

are covered by this proposed regulation 

when they are physically or functionally 

integrated with the control system and 

they perform functions that affect 

engine safety or are used to effect 

continued-operation or return-to-service 

decisions. 

The purpose of § 33.28 is to set 

objectives for the general design and 

functioning of the engine control 

system. These requirements are not 

intended to replace or supersede other 

requirements, such as § 33.67 for the 

fuel system. Therefore, individual 

components of the control system, such 

as alternators, sensors, actuators, should 

be covered, in addition, under other part 

33 paragraphs such as § 33.53 and 

§ 33.91 as appropriate. 

Although the proposed rule would 

cover all types of engine control systems 

(including hydromechanical and 

reciprocating engine controls), it would 

not cover one particular simple electromechanical device—the conventional 

magneto—because that device is not a 

true control component. On the other 

hand, the proposed rule would cover 

subsystems controlled by a FADEC 

because this is considered part of the 

engine control system. FADECs are 

standard on virtually all new turbine 

engines, and are now being put on some 

new reciprocating engines also. 

This proposal would lower costs by 

establishing uniform certification 

standards for all engine control systems 

certified in the United States under part 

33 and in European countries under 

EASA regulations, simplifying 

airworthiness approvals for import and 

export. In addition, a potential for 

increased safety lies in having more 

clear and explicit regulations, but the 

FAA was unable to quantify this benefit. 

The FAA concludes that the benefits of 

this rule justify the costs. The FAA 

requests comments with supporting 

justification about the FAA 

determination of minimal impact. 

The FAA has, therefore, determined 

that this proposed rule is not a 

‘‘significant regulatory action’’ as 

defined in section 3(f) of Executive 

Order 12866, and is not ‘‘significant’’ as 

defined in DOT’s Regulatory Policies 

and Procedures. 

Regulatory Flexibility Determination 

The Regulatory Flexibility Act of 1980 

(Pub. L. 96–354) (RFA) establishes ‘‘as a 

principle of regulatory issuance that 

agencies shall endeavor, consistent with 

the objectives of the rule and of 

applicable statutes, to fit regulatory and 

informational requirements to the scale 

of the businesses, organizations, and 

governmental jurisdictions subject to 

regulation. To achieve this principle, 

agencies are required to solicit and 

consider flexible regulatory proposals 

and to explain the rationale for their 

actions to assure that such proposals are 

given serious consideration.’’ The RFA 

covers a wide-range of small entities, 

including small businesses, not-forprofit organizations, and small 

governmental jurisdictions. 

Agencies must perform a review to 

determine whether a rule will have a 

significant economic impact on a 


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substantial number of small entities. If 

the agency determines that it will, the 

agency must prepare a regulatory 

flexibility analysis as described in the 

RFA. 

However, if an agency determines that 

a rule is not expected to have a 

significant economic impact on a 

substantial number of small entities, 

section 605(b) of the RFA provides that 

the head of the agency may so certify 

and a regulatory flexibility analysis is 

not required. The certification must 

include a statement providing the 

factual basis for this determination, and 

the reasoning should be clear. 

The FAA believes that this proposed 

rule would not have a significant 

economic impact on a substantial 

number of small entities because only 

one U.S. engine manufacturer meets the 

definition of small business contained 

in the Small Business Administration’s 

small business size standard 

regulations. Therefore, the FAA certifies 

that this proposed rule would not have 

a significant economic impact on a 

substantial number of small entities. 

The FAA solicits comments regarding 

this determination. 

Trade Impact Assessment 

The Trade Agreements Act of 1979 

(Pub. L. 96–39) prohibits Federal 

agencies from establishing any 

standards or engaging in related 

activities that create unnecessary 

obstacles to the foreign commerce of the 

United States. Legitimate domestic 

objectives, such as safety, are not 

considered unnecessary obstacles. The 

statute also requires consideration of 

international standards and, where 

appropriate, that they be the basis for 

U.S. standards. The FAA has assessed 

the potential effect of this rulemaking 

and determined that it uses European 

standards as the basis for U.S. 

regulations. 

Unfunded Mandates Assessment 

Title II of the Unfunded Mandates 

Reform Act of 1995 (Pub. L. 104–4) 

requires each Federal agency to prepare 

a written statement assessing the effects 

of any Federal mandate in a proposed or 

final agency rule that may result in an 

expenditure of $100 million or more 

(adjusted annually for inflation) in any 

one year by State, local, and tribal 

governments, in the aggregate, or by the 

private sector; such a mandate is 

deemed to be a ‘‘significant regulatory 

action.’’ The FAA currently uses an 

inflation-adjusted value of $128.1 

million in lieu of $100 million. 

This proposed rule does not contain 

such a mandate. The requirements of 

Title II do not apply. 

Executive Order 13132, Federalism 

The FAA has analyzed this proposed 

rule under the principles and criteria of 

Executive Order 13132, Federalism. We 

determined that this action would not 

have a substantial direct effect on the 

States, on the relationship between the 

national Government and the States, or 

on the distribution of power and 

responsibilities among the various 

levels of government, and therefore 

would not have federalism implications. 

Environmental Analysis 

FAA Order 1050.1E identifies FAA 

actions that are categorically excluded 

from preparation of an environmental 

assessment or environmental impact 

statement under the National 

Environmental Policy Act in the 

absence of extraordinary circumstances. 

We determined that this proposed 

rulemaking action qualifies for the 

categorical exclusion identified in 

Chapter 3, paragraph 312d and involves 

no extraordinary circumstances. 

Regulations that Significantly Affect 

Energy Supply, Distribution, or Use 

The FAA has analyzed this NPRM 

under Executive Order 13211, Actions 

Concerning Regulations that 

Significantly Affect Energy Supply, 

Distribution, or Use (May 18, 2001). We 

determined that it is not a ‘‘significant 

energy action’’ under the executive 

order because it is not a ‘‘significant 

regulatory action’’ under Executive 

Order 12866, and it is not likely to have 

a significant adverse effect on the 

supply, distribution, or use of energy. 

List of Subjects in 14 CFR Part 33 

Aircraft, Air transportation, Aviation 

safety, Safety. 

The Proposed Amendment 

In consideration of the foregoing, the 

Federal Aviation Administration 

proposes to amend chapter I of Title 14, 

Code of Federal Regulations, as follows: 

PART 33—AIRWORTHINESS 

STANDARDS: AIRCRAFT ENGINES 

1. The authority citation for part 33 

continues to read as follows: 

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

44702, 44704. 

2. Amend § 33.5 by adding new 

paragraphs (a)(4), (a)(5), (a)(6), and 

(b)(4), to read as follows: 

§ 33.5 Instruction manual for installing and 

operating the engine. 

* * * * * 

(a) * * * 

(4) A definition of the physical and 

functional interfaces with the aircraft 

and aircraft equipment, including the 

propeller when applicable. 

(5) Where an engine system relies on 

components that are not part of the 

engine type design, the interface 

conditions and reliability requirements 

for those components upon which 

engine type certification is based must 

be specified in the engine installation 

instructions directly or by reference to 

appropriate documentation. 

(6) A list of the instruments necessary 

for control of the engine, including the 

overall limits of accuracy and transient 

response required of such instruments 

for control of the operation of the 

engine, must also be stated so that the 

suitability of the instruments as 

installed may be assessed. 

(b) * * * 

(4) A description of the primary and 

all alternate modes, and any back-up 

system, together with any associated 

limitations, of the engine control system 

and its interface with the aircraft 

systems, including the propeller when 

applicable. 

3. Amend § 33.7 by adding new 

paragraph (d) to read as follows: 

§ 33.7 Engine ratings and operating 

limitations. 

* * * * * 

(d) In determining the engine 

performance and operating limitations, 

the overall limits of accuracy of the 

engine control system and of the 

necessary instrumentation as defined in 

§ 33.5(a)(6) must be taken into account. 

4. Amend § 33.27 by revising 

paragraph (b) to read as follows: 

§ 33.27 Turbine, compressor, fan, and 

turbosupercharger rotors. 

* * * * * 

(b) The design and functioning of 

engine systems, instruments, and other 

methods, not covered under § 33.28 of 

this part must give reasonable assurance 

that those engine operating limitations 

that affect turbine, compressor, fan, and 

turbosupercharger rotor structural 

integrity will not be exceeded in service. 

* * * * * 

5. Revise § 33.28 to read as follows: 

§ 33.28 Engine control systems. 

(a) Applicability. These requirements 

are applicable to any system or device 

that is part of engine type design, that 

controls, limits, or monitors engine 

operation, and is necessary for the 

continued airworthiness of the engine. 

(b) Validation. (1) Functional aspects. 

The applicant must substantiate by 

tests, analysis, or a combination thereof, 

that the engine control system performs 

the intended functions in a manner 

which: 


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(i) Enables selected values of relevant 

control parameters to be maintained and 

the engine kept within the approved 

operating limits over changing 

atmospheric conditions in the declared 

flight envelope; 

(ii) Complies with the operability 

requirements of §§ 33.51, 33.65 and 

33.73, as appropriate, under all likely 

system inputs and allowable engine 

power or thrust demands, unless it can 

be demonstrated that this is not required 

for non-dispatchable specific control 

modes in the intended application, in 

which case the engine would be 

approved; 

(iii) Allows modulation of engine 

power or thrust with adequate 

sensitivity over the declared range of 

engine operating conditions; and 

(iv) Does not create unacceptable 

power or thrust oscillations. 

(2) Environmental limits. The 

applicant must demonstrate, when 

complying with §§ 33.53 or 33.91, that 

the engine control system functionality 

will not be adversely affected by 

declared environmental conditions, 

including electromagnetic interference 

(EMI), High Intensity Radiated Fields 

(HIRF), and lightning. The limits to 

which the system has been qualified 

must be documented in the engine 

installation instructions. 

(c) Control transitions. (1) The 

applicant must demonstrate that, when 

fault or failure results in a change from 

one control mode to another, from one 

channel to another, or from the primary 

system to the back-up system, the 

change occurs so that: 

(i) The engine does not exceed any of 

its operating limitations; 

(ii) The engine does not surge, stall, 

or experience unacceptable thrust or 

power changes or oscillations or other 

unacceptable characteristics; and 

(iii) There is a means to alert the flight 

crew if the crew is required to initiate, 

respond to, or be aware of the control 

mode change. The means to alert the 

crew must be described in the engine 

installation instructions, and the crew 

action must be described in the engine 

operating instructions; 

(2) The magnitude of any change in 

thrust or power and the associated 

transition time must be identified and 

described in the engine installation 

instructions and the engine operating 

instructions. 

(d) Engine control system failures. 

The applicant must design and 

construct the engine control system so 

that: 

(1) The rate for Loss of Thrust (or 

Power) Control (LOTC/LOPC) events, 

consistent with the safety objective 

associated with the intended 

application can be achieved; 

(2) In the full-up configuration, the 

system is single fault tolerant, as 

determined by the Administrator, for 

electrical or electronic failures with 

respect to LOTC/LOPC events, 

(3) Single failures of engine control 

system components do not result in a 

hazardous engine effect, and 

(4) Foreseeable failures or 

malfunctions leading to local events in 

the intended aircraft installation, such 

as fire, overheat, or failures leading to 

damage to engine control system 

components, do not result in a 

hazardous engine effect due to engine 

control system failures or malfunctions. 

(e) System safety assessment. When 

complying with §§ 33.28 and 33.75, the 

applicant must complete a System 

Safety Assessment for the engine control 

system. This assessment must identify 

faults or failures that result in a change 

in thrust or power, transmission of 

erroneous data, or an effect on engine 

operability together with the predicted 

frequency of occurrence of these faults 

or failures. 

(f) Protection systems. (1) The design 

and functioning of engine control 

devices and systems, together with 

engine instruments and operating and 

maintenance instructions, must provide 

reasonable assurance that those engine 

operating limitations that affect turbine, 

compressor, fan, and turbosupercharger 

rotor structural integrity will not be 

exceeded in service. 

(2) When electronic overspeed 

protection systems are provided, the 

design must include a means for testing, 

at least once per engine start/stop cycle, 

to establish the availability of the 

protection function. The means must be 

such that a complete test of the system 

can be achieved in the minimum 

number of cycles. If the test is not fully 

automatic, the requirement for a manual 

test must be contained in the engine 

instructions for operation. 

(3) When overspeed protection is 

provided through hydromechanical or 

mechanical means, the applicant must 

demonstrate by test or other acceptable 

means that the overspeed function 

remains available between inspection 

and maintenance periods. 

(g) Software. The applicant must 

design, implement, and verify all 

associated software to minimize the 

existence of errors by using a method, 

approved by the FAA, consistent with 

the criticality of the performed 

functions. 

(h) Aircraft-supplied data. Single 

failures leading to loss, interruption or 

corruption of aircraft-supplied data 

(other than thrust or power command 

signals from the aircraft), or data shared 

between engines must: 

(1) Not result in a hazardous engine 

effect for any engine; and 

(2) Be detected and accommodated. 

The accommodation strategy must not 

result in an unacceptable change in 

thrust or power or an unacceptable 

change in engine operating and starting 

characteristics. The applicant must 

evaluate and document the effects of 

these failures on engine power or thrust, 

engine operability, and starting 

characteristics throughout the flight 

envelope. 

(i) Aircraft-supplied electrical power. 

(1) The applicant must design the 

engine control system so that the loss, 

malfunction, or interruption of electrical 

power supplied from the aircraft to the 

engine control system will not result in 

any of the following: 

(i) A hazardous engine effect, or 

(ii) The unacceptable transmission of 

erroneous data. 

(2) When an engine dedicated power 

source is required for compliance with 

§ 33.28(i)(1), its capacity should provide 

sufficient margin to account for engine 

operation below idle where the engine 

control system is designed and expected 

to recover engine operation 

automatically. 

(3) The applicant must identify and 

declare the need for, and the 

characteristics of, any electrical power 

supplied from the aircraft to the engine 

control system for starting and operating 

the engine, including transient and 

steady state voltage limits, in the engine 

instructions for installation. 

(4) Low voltage transients outside the 

power supply voltage limitations 

declared in § 33.28(i)(3) must meet the 

requirements of § 33.28(i)(1). The engine 

control system must be capable of 

resuming normal operation when 

aircraft-supplied power returns to 

within the declared limits. 

(j) Air pressure signal. The applicant 

must consider the effects of blockage or 

leakage of the signal lines on the engine 

control system as part of the system 

safety assessment of § 33.28(e) and must 

adopt the appropriate design 

precautions. 

(k) Automatic availability and control 

of engine power for 30-second OEI 

rating. Rotorcraft engines having a 30- 

second OEI rating must incorporate a 

means, or a provision for a means, for 

automatic availability and automatic 

control of the 30-second OEI power 

within its operating limitations. 

(l) Engine shut down means. Means 

must be provided for shutting down the 

engine rapidly. 

(m) Programmable logic devices. The 

development of programmable logic 


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devices using digital logic or other 

complex design technologies must 

provide a level of assurance for the 

encoded logic commensurate with the 

hazard associated with the failure or 

malfunction of the systems in which the 

devices are located. The applicant must 

design, implement, and verify all 

associated logic to minimize the 

existence of errors by using a method, 

approved by the FAA, that is consistent 

with the criticality of the performed 

function. 

6. Amend § 33.29 by adding new 

paragraphs (e) through (h) to read as 

follows: 

§ 33.29 Instrument connection. 

* * * * * 

(e) The applicant must make 

provision for the installation of 

instrumentation necessary to ensure 

operation in compliance with engine 

operating limitations. Where, in 

presenting the safety analysis, or 

complying with any other requirement, 

dependence is placed on 

instrumentation that is not otherwise 

mandatory in the assumed aircraft 

installation, then the applicant must 

specify this instrumentation in the 

engine installation instructions and 

declare it mandatory in the engine 

approval documentation. 

(f) As part of the System Safety 

Assessment of § 33.28(e), the applicant 

must assess the possibility and 

subsequent effect of incorrect fit of 

instruments, sensors, or connectors. 

Where necessary, the applicant must 

take design precautions to prevent 

incorrect configuration of the system. 

(g) The sensors, together with 

associated wiring and signal 

conditioning, must be segregated, 

electrically and physically, to the extent 

necessary to ensure that the probability 

of a fault propagating from 

instrumentation and monitoring 

functions to control functions, or vice 

versa, is consistent with the failure 

effect of the fault. 

(h) The applicant must provide 

instrumentation enabling the flight crew 

to monitor the functioning of the turbine 

cooling system unless appropriate 

inspections are published in the 

relevant manuals and evidence shows 

that: 

(1) Other existing instrumentation 

provides adequate warning of failure or 

impending failure; 

(2) Failure of the cooling system 

would not lead to hazardous engine 

effects before detection; or 

(3) The probability of failure of the 

cooling system is extremely remote. 

7. Amend § 33.53 by revising the 

section heading and paragraph (a) to 

read as follows: 

§ 33.53 Engine system and component 

tests. 

(a) For those systems and components 

that cannot be adequately substantiated 

in accordance with endurance testing of 

§ 33.49, the applicant must conduct 

additional tests to demonstrate that 

systems or components are able to 

perform the intended functions in all 

declared environmental and operating 

conditions. 

* * * * * 

§ 33.67 [Amended] 

8. Remove paragraph (d) from § 33.67. 

9. Amend § 33.91 by revising the 

section heading and paragraph (a) to 

read as follows: 

§ 33.91 Engine system and component 

tests. 

(a) For those systems or components 

that cannot be adequately substantiated 

in accordance with endurance testing of 

§ 33.87, the applicant must conduct 

additional tests to demonstrate that the 

systems or components are able to 

perform the intended functions in all 

declared environmental and operating 

conditions. 

* * * * * 

Issued in Washington, DC, on March 26, 

2007. 

John J. Hickey, 

Director, Aircraft Certification Service. 

[FR Doc. E7–6535 Filed 4–10–07; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2007–27532; Directorate 

Identifier 2007–CE–021–AD] 

RIN 2120–AA64 

Airworthiness Directives; Piaggio Aero 

Industries S.p.A. P–180 Airplanes 

AGENCY: Federal Aviation 

Administration (FAA), Department of 

Transportation (DOT). 

ACTION: Notice of proposed rulemaking 

(NPRM). 

SUMMARY: We propose to adopt a new 

airworthiness directive (AD) for the 

products listed above. This proposed 

AD results from mandatory continuing 

airworthiness information (MCAI) 

originated by an aviation authority of 

another country to identify and correct 

an unsafe condition on an aviation 

product. The MCAI describes the unsafe 

condition as: 

One P–180 aircraft experienced a jamming 

of its longitudinal flight control cables. 

Investigations revealed that its fuselage drain 

holes were plugged, and water was trapped 

in the lower fuselage. 

As a consequence of plugged drain holes, 

water can accumulate and freeze when the 

aircraft reaches and holds altitudes where 

temperature is below the freezing point. If 

not corrected this may cause the loss of 

control of the airplane. 

The proposed AD would require 

actions that are intended to address the 

unsafe condition described in the MCAI. 

DATES: We must receive comments on 

this proposed AD by May 11, 2007. 

ADDRESSES: You may send comments by 

any of the following methods: 

• DOT Docket Web Site: Go to http:// 

dms.dot.gov and follow the instructions 

for sending your comments 

electronically. 

• Fax: (202) 493–2251. 

• Mail: Docket Management Facility, 

U.S. Department of Transportation, 400 

Seventh Street, SW., Nassif Building, 

Room PL–401, Washington, DC 20590–

0001. 

• Hand Delivery: Room PL–401 on 

the plaza level of the Nassif Building, 

400 Seventh Street, SW., Washington, 

DC, between 9 a.m. and 5 p.m., Monday 

through Friday, except Federal holidays. 

• Federal eRulemaking Portal: Go to 

http://www.regulations.gov. Follow the 

instructions for submitting comments. 

Examining the AD Docket 

You may examine the AD docket on 

the Internet at http://dms.dot.gov; or in 

person at the Docket Management 

Facility between 9 a.m. and 5 p.m., 

Monday through Friday, except Federal 

holidays. The AD docket contains this 

proposed AD, the regulatory evaluation, 

any comments received, and other 

information. The street address for the 

Docket Office (telephone (800) 647–

5227) is in the ADDRESSES section. 

Comments will be available in the AD 

docket shortly after receipt. 

FOR FURTHER INFORMATION CONTACT: 

Sarjapur Nagarajan, Aerospace Engineer, 

FAA, Small Airplane Directorate, 901 

Locust, Room 301, Kansas City, 

Missouri 64106; telephone: (816) 329–

4145; fax: (816) 329–4090. 

SUPPLEMENTARY INFORMATION: 

Streamlined Issuance of AD 

The FAA is implementing a new 

process for streamlining the issuance of 

ADs related to MCAI. This streamlined 

process will allow us to adopt MCAI 


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