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contains regulatory documents having general

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are keyed to and codified in the Code of

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Rules and Regulations Federal Register

56525 

Vol. 77, No. 178 

Thursday, September 13, 2012 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 25 

[Docket No. FAA–2012–0968; Special 

Conditions No. 25–467–SC] 

Special Conditions: Bombardier, Model 

CL–600–2B16 Airplane (CL–601–3A, 

CL–601–3R, and CL–604 Variants); 

Enhanced Flight Vision System 

AGENCY: Federal Aviation 

Administration (FAA), DOT. 

ACTION: Final special conditions; request 

for comments. 

SUMMARY: These special conditions are 

issued for the Bombardier Model CL– 

600–2B16 airplanes, including variants 

CL–601–3A, CL–601–3R and CL–604. 

This airplane, as modified by Atlantic 

Aero, Inc., will have a novel or unusual 

design feature associated with an 

advanced, enhanced flight vision system 

(EFVS). The EFVS consists of a head-up 

display (HUD) system modified to 

display forward-looking infrared (FLIR) 

imagery. The applicable airworthiness 

regulations do not contain adequate or 

appropriate safety standards for this 

design feature. These 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: The effective date of these 

special conditions is September 6, 2012. 

We must receive your comments by 

October 29, 2012. 

ADDRESSES: Send comments identified 

by docket number FAA–2012–0968 

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: Dale 

Dunford, FAA, Transport Standards 

Staff, ANM–111, Transport Airplane 

Directorate, Aircraft Certification 

Service, 1601 Lind Avenue SW., 

Renton, Washington 98057–3356; 

telephone 425–227–2239; facsimile 

425–227–1320; email: 

dale.dunford@faa.gov. 

SUPPLEMENTARY INFORMATION: The FAA 

has determined that notice of, and 

opportunity for prior public comment 

on, these special conditions are 

impracticable because these procedures 

would significantly delay issuance of 

the design approval and thus delivery of 

the affected aircraft. In addition, the 

substance of these special conditions 

has been subject to the public comment 

process in several prior instances with 

no substantive comments received. The 

FAA therefore finds that good cause 

exists for making these special 

conditions effective upon issuance. 

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 by the closing date for 

comments. We may change these special 

conditions based on the comments we 

receive. 

Background 

On October 7, 2011, Atlantic Aero, 

Inc., applied for a supplemental type 

certificate (STC) for the installation and 

operation of a HUD and an EFVS in the 

Bombardier Model CL–600–2B16 (CL– 

601–3A, CL–601–3R, and CL–604 

variants). The original type certificate 

for the CL–600–2B16 is A21EA, dated 

April 30, 1987, and is now at revision 

31, dated May 25, 2011. 

The Model CL–600–2B16 is a 22- 

passenger, transport category airplane 

that operates with a crew of two. It is 

powered by two General Electric 

engines and has a maximum takeoff 

weight of 43,100 pounds for the CL– 

601–3A and 3R variants and 47,600 

pounds for the CL–604 variant. 

The electronic infrared image 

displayed between the pilot and the 

forward windshield represents a novel 

or unusual design feature in the context 

of Title 14, Code of Federal Regulations 

(14 CFR) 25.773. Section 25.773 was not 

written in anticipation of such 

technology. The electronic image has 

the potential to enhance the pilot’s 

awareness of the terrain, hazards, and 

airport features. At the same time, the 

image may partially obscure the pilot’s 

direct outside compartment view. 

Therefore, the FAA needs adequate 

safety standards to evaluate the EFVS to 

determine that the imagery provides the 

intended visual enhancements without 

undue interference with the pilot’s 

outside compartment view. The FAA’s 

intent is that the pilot will be able to use 

a combination of the information seen 

in the image and the natural view of the 

outside scene, as seen through the 

image, as safely and effectively as a pilot 

compartment view without an enhanced 

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56526 Federal Register / Vol. 77, No. 178 / Thursday, September 13, 2012 / Rules and Regulations 

vision system (EVS) image, and that it 

is compliant with § 25.773. 

Although the FAA has determined 

that the existing regulations are not 

adequate for certification of EFVSs, it 

believes that EFVSs could be certified 

through application of appropriate 

safety criteria. Therefore, the FAA has 

determined that special conditions 

should be issued for certification of 

EFVSs to provide a level of safety 

equivalent to that provided by the 

standard in § 25.773. 

Note: The term ‘‘enhanced vision system’’ 

(EVS) in this document refers to a system 

comprised of a head-up display (HUD), 

imaging sensor(s), and avionics interfaces 

that display the sensor imagery on the HUD, 

and overlay that imagery with alpha-numeric 

and symbolic flight information. However, 

the term has also been commonly used in 

reference to systems that display the sensor 

imagery, with or without other flight 

information, on a head-down display. For 

clarity, the FAA created the term ‘‘enhanced 

flight vision system’’ (EFVS) to refer to 

certain EVS systems that meet the 

requirements of the new operational rules— 

in particular, the requirement for a HUD and 

specified flight information—and which can 

be used to determine ‘‘enhanced flight 

visibility.’’ An EFVS can be considered a 

subset of a system otherwise labeled EVS. 

On January 9, 2004, the FAA 

published revisions to operational rules 

in 14 CFR parts 1, 91, 121, 125, and 135 

to allow aircraft to operate below certain 

altitudes during a straight-in instrument 

approach while using an EFVS to meet 

visibility requirements. 

Prior to this rule change, the FAA 

issued Special Conditions No. 25–180– 

SC, which applied to an EVS installed 

on Gulfstream Model G–V airplanes. 

Those special conditions addressed the 

requirements for the pilot compartment 

view and limited the scope of the 

intended functions permissible under 

the operational rules at the time. The 

intended function of the EVS imagery 

was to aid the pilot during the approach 

and allow the pilot to detect and 

identify the visual references for the 

intended runway down to 100 feet 

above the touchdown zone. However, 

the EVS imagery alone was not to be 

used as a means to satisfy visibility 

requirements below 100 feet. 

The recent operational rule change 

expands the permissible application of 

certain EVSs that are certified to meet 

the new EFVS standards. The new rule 

allows the use of an EFVS for operation 

below the minimum descent altitude or 

decision height to meet new visibility 

requirements of § 91.175(l). The purpose 

of these special conditions is not only 

to address the issue of the ‘‘pilot 

compartment view,’’ as was done by 

Special Conditions No. 25–180–SC, but 

also to define the scope of intended 

function consistent with § 91.175(l) and 

(m). 

Type Certification Basis 

Under the provisions of § 21.101, 

Atlantic Aero, Inc., must show that the 

Bombardier Model CL–600–2B16 (CL– 

601–3A, CL–601–3R, and CL–604 

variants), as changed, continues to meet 

the applicable provisions of the 

regulations incorporated by reference in 

Type Certificate No. A21EA or the 

applicable regulations in effect on the 

date of application for the change. The 

regulations incorporated by reference in 

the type certificate are commonly 

referred to as the ‘‘original type 

certification basis.’’ The regulations 

incorporated by reference are listed in 

Type Certificate Data Sheet No. A21EA, 

Revision 31, dated May 25, 2011, which 

covers all variants of the Bombardier 

CL–600–2B16 airplanes. In addition, the 

certification basis includes certain 

special conditions and exemptions that 

are not relevant to these special 

conditions. 

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 Bombardier Model CL–600–2B16 

because of a novel or unusual design 

feature, special conditions are 

prescribed under the provisions of 

§ 21.16. 

Special conditions are initially 

applicable to the model for which they 

are issued. Should the applicant apply 

for a supplemental type certificate to 

modify any other model included on the 

same type certificate to incorporate the 

same novel or unusual design feature, 

the special conditions would also apply 

to the other model. 

In addition to the applicable 

airworthiness regulations and special 

conditions, the Model CL–600–2B16 

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. 

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 

§ 21.101. 

Novel or Unusual Design Features 

The Bombardier Model CL–600–2B16 

will incorporate the following novel or 

unusual design feature: An EFVS that 

projects a video image derived from a 

FLIR camera through the HUD. The 

EFVS image is projected in the center of 

the ‘‘pilot compartment view,’’ which is 

governed by § 25.773. The image is 

displayed with HUD symbology and 

overlays the forward outside view. 

Therefore, § 25.773 does not contain 

appropriate safety standards for the 

EFVS display. 

Operationally, during an instrument 

approach, the EFVS image is intended 

to enhance the pilot’s ability to detect 

and identify ‘‘visual references for the 

intended runway’’ [see § 91.175(l)(3)] to 

continue the approach below decision 

height or minimum descent altitude. 

Depending on atmospheric conditions 

and the strength of infrared energy 

emitted and/or reflected from the scene, 

the pilot can see these visual references 

in the image better than they can be 

seen through the window without 

EFVS. 

Scene contrast detected by infrared 

sensors can be much different from that 

detected by natural pilot vision. On a 

dark night, thermal differences of 

objects which are not detectable by the 

unaided eye are easily detected by many 

imaging infrared systems. On the other 

hand, contrasting colors in visual 

wavelengths may be distinguished by 

the unaided eye but not by an imaging 

infrared system. Where thermal contrast 

in the scene is sufficiently detectable, 

the pilot can recognize shapes and 

patterns of certain visual references in 

the infrared image. However, depending 

on conditions, those shapes and 

patterns in the infrared image can 

appear significantly different than they 

would with normal vision. Considering 

these factors, the EFVS image needs to 

be evaluated to determine that it can be 

accurately interpreted by the pilot. 

The EFVS image may improve the 

pilot’s ability to detect and identify 

items of interest. However, the EFVS 

needs to be evaluated to determine that 

the imagery allows the pilot to perform 

the normal flightcrew duties and 

adequately see outside the window 

through the image, consistent with the 

safety intent of § 25.773(a)(2). 

Compared to a HUD displaying the 

EFVS image and symbology, a HUD that 

only displays stroke-written symbols is 

easier to see through. Stroke symbology 

illuminates a small fraction of the total 

display area of the HUD, leaving much 

of that area free of reflected light that 

could interfere with the pilot’s view out 

the window through the display. 

However, unlike stroke symbology, the 

video image illuminates most of the 

total display area of the HUD 

(approximately 30 degrees horizontally 

and 25 degrees vertically), which is a 

significant fraction of the pilot 

compartment view. The pilot cannot see 

around the larger illuminated portions 

of the video image, but must see the 

outside scene through it. 

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Federal Register / Vol. 77, No. 178 / Thursday, September 13, 2012 / Rules and Regulations 56527 

Unlike the pilot’s external view, the 

EFVS image is a monochrome, twodimensional display. Many, but not all, 

of the depth cues found in the natural 

view are also found in the image. The 

quality of the EFVS image and the level 

of EFVS infrared-sensor performance 

could depend significantly on 

conditions of the atmospheric and 

external light sources. The pilot needs 

adequate control of sensor gain and 

image brightness, which can 

significantly affect image quality and 

transparency (i.e., the ability to see the 

outside view through the image). 

Certain system characteristics could 

create distracting and confusing display 

artifacts. Finally, because this is a 

sensor-based system intended to 

provide a conformal perspective 

corresponding with the outside scene, 

the system must be able to ensure 

accurate alignment. Therefore, safety 

standards are needed for each of the 

following factors: 

• An acceptable degree of image 

transparency; 

• Image alignment; 

• Lack of significant distortion; and 

• The potential for pilot confusion or 

misleading information. 

Section 25.773, ‘‘Pilot compartment 

view,’’ specifies that ‘‘Each pilot 

compartment must be free of glare and 

reflection that could interfere with the 

normal duties of the minimum flight 

crew * * *.’’ In issuing § 25.773, the 

FAA did not anticipate the development 

of the EFVS and does not consider that 

§ 25.773 adequately addresses the 

specific issues related to such a system. 

Therefore, the FAA has determined that 

special conditions are needed to address 

the specific issues particular to the 

installation and use of an EFVS. 

Discussion 

The EFVS is intended to present an 

enhanced view during the landing 

approach. This enhanced view would 

help the pilot see and recognize external 

visual references, as required by 

§ 91.175(l), and to visually monitor the 

integrity of the approach, as described 

in FAA Order 6750.24D, ‘‘Instrument 

Landing System and Ancillary 

Electronic Component Configuration 

and Performance Requirements,’’ dated 

March 1, 2000. 

Based on this approved functionality, 

users would seek to obtain operational 

approval to conduct approaches, 

including approaches to Type I 

runways, in visibility conditions much 

lower than those for conventional 

Category I. 

The purpose of these special 

conditions is to ensure that the EFVS to 

be installed can perform the following 

functions: 

• Present an enhanced view that aids 

the pilot during the approach. 

• Provide enhanced flight visibility to 

the pilot that is no less than the 

visibility prescribed in the standard 

instrument approach procedure. 

• Display an image that the pilot can 

use to detect and identify the ‘‘visual 

references for the intended runway’’ 

required by § 91.175(l)(3) to continue 

the approach with vertical guidance to 

100 feet height above the touchdownzone elevation. 

Depending on the atmospheric 

conditions and the particular visual 

references that happen to be distinctly 

visible and detectable in the EFVS 

image, these functions would support 

its use by the pilot to visually monitor 

the integrity of the approach path. 

Compliance with these special 

conditions does not affect the 

applicability of any of the requirements 

of the operating regulations (i.e., 14 CFR 

parts 91, 121, and 135). Furthermore, 

use of the EFVS does not change the 

approach minima prescribed in the 

standard instrument approach 

procedure being used; published 

minima still apply. 

The FAA certification of this EFVS is 

limited as follows: 

1. The infrared-based EFVS image 

will not be certified as a means to satisfy 

the requirements for descent below 100 

feet height above touchdown. 

2. The EFVS may be used as a 

supplemental device to enhance the 

pilot’s situational awareness during any 

phase of flight or operation in which its 

safe use has been established. 

An EFVS image may provide an 

enhanced image of the scene that may 

compensate for any reduction in the 

clear outside view of the visual field 

framed by the HUD combiner. The pilot 

must be able to use this combination of 

information seen in the image and the 

natural view of the outside scene, as 

seen through the image, as safely and 

effectively as the pilot would use a pilot 

compartment view without an EVS 

image that is compliant with § 25.773. 

This is the fundamental objective of the 

special conditions. 

The FAA will also apply additional 

certification criteria, not as special 

conditions, for compliance with related 

regulatory requirements, such as 

§§ 25.1301 and 25.1309. These 

additional criteria address certain image 

characteristics, installation, 

demonstration, and system safety. 

Image-characteristics criteria include 

the following: 

• Resolution 

• Luminance 

• Luminance uniformity 

• Low-level luminance 

• Contrast variation 

• Display quality 

• Display dynamics (e.g., jitter, flicker, 

update rate, and lag) 

• Brightness controls 

Installation criteria address visibility 

and access to EFVS controls and 

integration of EFVS in the cockpit. 

The EFVS demonstration criteria 

address the flight and environmental 

conditions that need to be covered. 

The FAA also intends to apply 

certification criteria relevant to highintensity radiated fields (HIRF) and 

lightning protection. 

Applicability 

As discussed above, these special 

conditions are applicable to the 

Bombardier Model CL–600–2B16 (CL– 

601–3A, CL–601–3R, and CL–604 

variants). Should Atlantic Aero, Inc., 

apply at a later date for a supplemental 

type certificate to modify any other 

model included on Type Certificate No. 

A21EA to incorporate 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 

series of airplanes. It is not a rule of 

general applicability and affects only 

the applicant who applied to the FAA 

for approval of these features on the 

airplane. 

The substance of these special 

conditions has been subjected to the 

notice and comment period in several 

prior instances and has been derived 

without substantive change from those 

previously issued. It is unlikely that 

prior public comment would result in a 

significant change from the substance 

contained herein. Therefore, because a 

delay would significantly affect the 

certification of the airplane, which is 

imminent, the FAA has determined that 

prior public notice and comment are 

unnecessary and impracticable, and 

good cause exists for adopting these 

special conditions upon issuance. The 

FAA is requesting comments to allow 

interested persons to submit views that 

may not have been submitted in 

response to the prior opportunities for 

comment described above. 

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: 

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56528 Federal Register / Vol. 77, No. 178 / Thursday, September 13, 2012 / Rules and Regulations 

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

44702, 44704. 

The Special Conditions 

Accordingly, pursuant to the 

authority delegated to me by the 

Administrator, the following special 

conditions are issued as part of the type 

certification basis for Bombardier Model 

CL–600–2B16 (CL–601–3A, CL–601–3R, 

and CL–604 variants) airplanes 

modified by Atlantic Aero, Inc. 

1. Enhanced flight vision system 

(EFVS) imagery on the head-up display 

(HUD) must not degrade the safety of 

flight or interfere with the effective use 

of outside visual references for required 

pilot tasks during any phase of flight in 

which it is to be used. 

2. To avoid unacceptable interference 

with the safe and effective use of the 

pilot compartment view, the EFVS 

device must meet the following 

requirements: 

a. The EFVS design must minimize 

unacceptable display characteristics or 

artifacts (e.g., noise, ‘‘burlap’’ overlay, 

running water droplets) that obscure the 

desired image of the scene, impair the 

pilot’s ability to detect and identify 

visual references, mask flight hazards, 

distract the pilot, or otherwise degrade 

task performance or safety. 

b. Automatic control of EFVS display 

brightness must be sufficiently effective, 

in dynamically changing background 

(ambient) lighting conditions, to prevent 

full or partial blooming of the display 

that would distract the pilot, impair the 

pilot’s ability to detect and identify 

visual references, mask flight hazards, 

or otherwise degrade task performance 

or safety. If automatic control for image 

brightness is not provided, it must be 

shown that a single manual setting is 

satisfactory for the range of lighting 

conditions encountered during a timecritical, high-workload phase of flight 

(e.g., low visibility instrument 

approach). 

c. A readily accessible control must be 

provided that permits the pilot to 

immediately deactivate and reactivate 

display of the EFVS image on demand 

without removing the pilot’s hands from 

the primary flight controls (yoke or 

equivalent) or thrust control. 

d. The EFVS image on the HUD must 

not impair the pilot’s use of guidance 

information, or degrade the presentation 

and pilot awareness of essential flight 

information displayed on the HUD, such 

as alerts, airspeed, attitude, altitude and 

direction, approach guidance, 

windshear guidance, traffic alert and 

collision avoidance system (TCAS) 

resolution advisories, or unusual 

attitude recovery cues. 

e. The EFVS image and the HUD 

symbols, which are spatially referenced 

to the pitch scale, outside view and 

image, must be scaled and aligned (i.e., 

conformal) to the external scene. In 

addition, the EFVS image and the HUD 

symbols, when considered singly or in 

combination, must not be misleading, 

cause pilot confusion, or increase 

workload. Airplane attitudes or 

crosswind conditions may cause certain 

symbols (e.g., the zero-pitch line or 

flight path vector) to reach field-of-view 

limits such that they cannot be 

positioned conformably with the image 

and external scene. In such cases, these 

symbols may be displayed but with an 

altered appearance, which makes the 

pilot aware that they are no longer 

displayed conformably (for example, 

‘‘ghosting’’). 

f. A HUD system used to display 

EFVS images must, if previously 

certified, continue to meet all of the 

requirements of the original approval. 

3. The safety and performance of the 

pilot tasks associated with the use of the 

pilot compartment view must not be 

degraded by the display of the EFVS 

image. Pilot tasks that must not be 

degraded by the EFVS image include: 

a. Detection, accurate identification, 

and maneuvering, as necessary, to avoid 

traffic, terrain, obstacles, and other 

hazards of flight. 

b. Accurate identification and 

utilization of visual references required 

for every task relevant to the phase of 

flight. 

Use of EFVS for instrument approach 

operations must be in accordance with 

the provisions of § 91.175(l) and (m) and 

§ 121.651 where applicable. Appropriate 

limitations must be stated in the 

operating limitations section of the 

airplane flight manual to prohibit the 

use of the EFVS for functions that have 

not been found to be acceptable. 

Issued in Renton, Washington, on 

September 6, 2012. 

Ali Bahrami 

Manager, Transport Airplane Directorate, 

Aircraft Certification Service. 

[FR Doc. 2012–22468 Filed 9–12–12; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2012–0896; Directorate 

Identifier 2010–SW–070–AD; Amendment 

39–17173; AD 2012–17–10] 

RIN 2120–AA64 

Airworthiness Directives; Various 

Restricted Category Helicopters 

AGENCY: Federal Aviation 

Administration (FAA), Department of 

Transportation (DOT). 

ACTION: Final rule; request for 

comments. 

SUMMARY: We are adopting a new 

airworthiness directive (AD) for various 

restricted category Model HH–1K, TH– 

1F, TH–1L, UH–1A, UH–1B, UH–1E, 

UH–1F, UH–1H, UH–1L, and UH–1P 

helicopters with certain main rotor (M/ 

R) blade assemblies installed, to require 

inspecting the grip plates, doublers, and 

upper and lower surfaces of the M/R 

blades in the area between blade 

stations 24.5 and 40 for an edge void, 

corrosion, or a crack. This AD is 

prompted by several reports of fatigue 

cracks on M/R blades installed on Bell 

Helicopter Textron, Inc. (Bell) Model 

212 helicopters. These same partnumbered M/R blades may also be 

installed on certain FAA-approved 

modified restricted category helicopters. 

These actions are intended to detect an 

edge void, corrosion, or a crack on an 

M/R blade, which could lead to loss of 

the M/R blade and subsequent loss of 

control of the helicopter. 

DATES: This AD becomes effective 

September 28, 2012. 

We must receive comments on this 

AD by November 13, 2012. 

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. 

Examining the AD Docket: You may 

examine the AD docket on the Internet 

at http://www.regulations.gov or in 

person at the Docket Operations Office 

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