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must highlight the information that you 

consider is CBI and explain why you 

believe this information should be held 

confidential. SBA will make a final 

determination, in its sole discretion, of 

whether the information is CBI and, 

therefore, will not be published. 

FOR FURTHER INFORMATION CONTACT: 

Linda Rusche, Supervisory Financial 

Analyst, at (816) 426–4860, or Bryan 

Hooper, Director, Office of Credit Risk 

Management, (202) 205–3049. 

Authority: 15 U.S.C. 634. 

Dated: December 11, 2007. 

Eric R. Zarnikow, 

Associate Administrator for the Office of 

Capital Access. 

[FR Doc. E7–24381 Filed 12–19–07; 8:45 am] 

BILLING CODE 8025–01–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 23 

[Docket No. CE275; Notice No. 23–07–04–

SC] 

Special Conditions: Aviation 

Technology Group, Inc., Javelin Model 

100; High Altitude Operations 

AGENCY: Federal Aviation 

Administration (FAA), DOT. 

ACTION: Notice of proposed special 

conditions. 

SUMMARY: This action proposes special 

conditions for the Aviation Technology 

Group, Inc., Javelin Model 100 airplane. 

This airplane will have a novel or 

unusual design feature(s) associated 

with high altitude operations. The 

applicable airworthiness regulations do 

not contain adequate or appropriate 

safety standards for these design 

features. 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: We must receive your comments 

by January 22, 2008. 

ADDRESSES: Mail two copies of your 

comments to: Federal Aviation 

Administration, Regional Counsel, 

ACE–7, 901 Locust, Room 506, Kansas 

City, Missouri 64106. You may deliver 

two copies to the Small Airplane 

Directorate at the above address. Mark 

your comments: Docket No. CE275. You 

may inspect comments in the Rules 

Docket weekdays, except Federal 

holidays, between 7:30 a.m. and 4 p.m. 

FOR FURTHER INFORMATION CONTACT: 

Leslie B. Taylor, Regulations & Policy 

Branch, ACE–111, Federal Aviation 

Administration, Small Airplane 

Directorate, Aircraft Certification 

Service, 901 Locust, Kansas City, MO 

64106; telephone (816) 329–4134; 

facsimile (816) 329–4090, e-mail at 

leslie.b.taylor@faa.gov. 

SUPPLEMENTARY INFORMATION: 

Comments Invited 

We invite interested parties 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 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 these special conditions. 

You may inspect the docket 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 7:30 a.m. and 

4 p.m., Monday through Friday, except 

Federal holidays. 

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 these special conditions 

based on 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 back to you. 

Background 

On February 15, 2005, Aviation 

Technology Group (ATG), 8001 S. 

InterPort Blvd., Englewood, CO 80112 

applied for a type certificate for their 

new Javelin Model 100 airplane. The 

Javelin Model 100 is a two-seat, 

pressurized, retractable-gear, composite 

airplane with two turbofan engines 

mounted in the aft fuselage. 

The Aviation Technology Group, Inc. 

(ATG) Javelin Model 100 will be 

certificated for operations at a maximum 

altitude of 45,000 feet. This unusually 

high operating altitude constitutes a 

novel or unusual design feature for 

which the applicable airworthiness 

regulations do not contain adequate or 

appropriate safety standards. Therefore, 

it is necessary to develop special 

conditions that provide the level of 

safety equivalent to that established by 

the regulations. 

ATG indicated they will fully comply 

with Special Conditions for a., Pressure 

Vessel Integrity; b., Ventilation; and c., 

Air Conditioning. 

However, ATG is unable to fully 

comply with Special Conditions d. 

Pressurization and e. Oxygen equipment 

and supply. As a result from these 

discussions, the Special Conditions d. 

and e. were revised to include an 

alternate means or compensating 

features that require the use of an 

oxygen system and emergency descent 

procedures that addresses a rapid 

decompression event. 

Discussion 

The 14 CFR part 23 certification basis 

for the ATG Javelin Model 100 is part 

23, Amendment 23–55. The FAA issues 

high altitude special conditions for 

airplanes when the certificated altitude 

exceeds human physiological limits. 

Crack growth could result in rapid 

depressurization to cabin altitudes that 

exceed human physiological limits. 

Damage tolerance methods are proposed 

to be used to assure pressure vessel 

integrity while operating at the higher 

altitudes. Crack growth data is used to 

prescribe an inspection program, which 

will detect cracks before an opening in 

the pressure vessel would allow rapid 

depressurization. Initial crack sizes for 

detection are determined under 

§ 23.571, Amendment 23–55. The cabin 

altitude after permissible crack growth 

may not exceed specified limits. 

To ensure that there is adequate fresh 

air for crewmembers to perform their 

duties, to provide reasonable passenger 

comfort, and to enable occupants to 

better withstand the effects of 

decompression at high altitudes, the 

ventilation system must be designed to 

provide 10 cubic feet of fresh air per 

minute per person during normal 

operations. Therefore, these special 

conditions require that crewmembers 

and passengers be provided with 10 

cubic feet of fresh air per minute per 

person. In addition, during the 

development of the supersonic transport 

special conditions, it was noted that 

certain pressurization failures resulted 

in hot ram or bleed air being used to 

maintain pressurization. Air 

conditioning special conditions are 

required because such a measure can 

lead to cabin temperatures that exceed 

human tolerance limits following 

probable and improbable failures. 

Continuous flow passenger oxygen 

equipment is certificated for use up to 

40,000 feet; however, for rapid 

decompressions above 34,000 feet, 

reverse diffusion leads to low oxygen 

partial pressures in the lungs, to the 

extent that a small percentage of 


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passengers may lose useful 

consciousness at 35,000 feet. The 

percentage increases to an estimated 60 

percent at 40,000 feet, even with the use 

of the continuous flow system. To 

prevent permanent physiological 

damage, the cabin altitude must not 

exceed 25,000 feet for more than 2 

minutes, or 40,000 feet for any time 

period. The maximum peak cabin 

altitude of 40,000 feet is consistent with 

the standards established for previous 

certification programs. 

Decompression above 37,000 feet can 

result in cabin altitudes that approach 

the physiological limits of the average 

person; therefore, every effort must be 

made to provide the pilot with adequate 

oxygen equipment to withstand these 

severe decompressions. Reducing the 

time interval between pressurization 

failure and the time the pilot receives 

oxygen will provide a safety margin 

against being incapacitated and can be 

accomplished by the use of maskmounted regulators. The proposed 

special condition, therefore, requires 

pressure demand masks with maskmounted regulators for the flight crew. 

This combination of equipment will 

provide the best practical protection for 

the failures covered by the proposed 

special conditions and for improbable 

failures not covered by the special 

conditions, provided the cabin altitude 

is limited. 

Type Certification Basis 

Under 14 CFR part 21, § 21.17, 

Aviation Technology Group, Inc. must 

show that the Javelin Model 100 meets 

the applicable provisions of part 23, as 

amended by Amendments 23–1 through 

23–55 thereto. 

If the Administrator finds that the 

applicable airworthiness regulations in 

part 23 do not contain adequate or 

appropriate safety standards for the 

Javelin Model 100 because of a novel or 

unusual design feature, special 

conditions are prescribed under § 21.16. 

In addition to the applicable 

airworthiness regulations and special 

conditions, the Javelin Model 100 must 

comply with the fuel vent and exhaust 

emission requirements of 14 CFR part 

34 and the noise certification 

requirements of 14 CFR part 36, and the 

FAA must issue a finding of regulatory 

adequacy under § 611 of Public Law 92–

574, the ‘‘Noise Control Act of 1972.’’

The FAA issues special conditions, as 

defined in § 11.19, under § 11.38, and 

they become part of the type 

certification basis under § 21.17(a)(2). 

Special conditions are initially 

applicable to the model for which they 

are issued. Should the type certificate 

for that model be amended later to 

include any other model that 

incorporates the same or similar novel 

or unusual design feature, the special 

conditions would also apply to the other 

model under § 21.101. 

Novel or Unusual Design Features 

The Javelin Model 100 will 

incorporate the following novel or 

unusual design features: 

Part 23 did not envision operation at 

the service ceiling requested for this 

airplane. The methods used to ensure 

pressure vessel integrity and to provide 

ventilation, air conditioning, 

pressurization, and supplemental 

oxygen will be unique due to that 

operating altitude. 

Applicability 

As discussed above, these special 

conditions are applicable to the Javelin 

Model 100. Should Aviation 

Technology Group, Inc., 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 under the 

provisions of § 21.101. 

Conclusion 

This action affects only certain novel 

or unusual design features on one model 

of airplane. It is not a rule of general 

applicability, and it affects only the 

applicant who applied to the FAA for 

approval of these features on the 

airplane. 

List of Subjects in 14 CFR Part 23 

Aircraft, Aviation safety, Signs and 

symbols. 

Citation 

The authority citation for these 

special conditions is as follows: 

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

44701; 14 CFR 21.16 and 21.17; and 14 CFR 

11.38 and 11.19. 

The Proposed Special Conditions 

Accordingly, the Federal Aviation 

Administration (FAA) proposes the 

following special conditions as part of 

the type certification basis for Aviation 

Technology Group, Inc., Javelin Model 

100 airplanes. 

a. Pressure Vessel Integrity. 

1. The maximum extent of failure and 

pressure vessel opening that can be 

demonstrated to comply with paragraph 

d (Pressurization) of this special 

condition must be determined. It must 

be demonstrated by crack propagation 

and damage tolerance analysis 

supported by testing that a larger 

opening or a more severe failure than 

demonstrated will not occur in normal 

operations. 

2. Inspection schedules and 

procedures must be established to 

ensure that cracks and normal fuselage 

leak rates will not deteriorate to the 

extent that an unsafe condition could 

exist during normal operation. 

b. Ventilation. In lieu of the 

requirements of § 23.831(b), the 

ventilation system must be designed to 

provide a sufficient amount of 

uncontaminated air to enable the 

crewmembers to perform their duties 

without undue discomfort or fatigue, 

and to provide reasonable passenger 

comfort during normal operating 

conditions and also in the event of any 

probable failure of any system which 

could adversely affect the cabin 

ventilating air. For normal operations, 

crewmembers and passengers must be 

provided with at least 10 cubic feet of 

fresh air per minute per person, or the 

equivalent in filtered, recirculated air 

based on the volume and composition at 

the corresponding cabin pressure 

altitude of not more than 8,000 feet. 

c. Air Conditioning. In addition to the 

requirements of § 23.831, paragraphs (b), 

the cabin cooling system must be 

designed to meet the following 

conditions during flight above 15,000 

feet mean sea level (MSL): 

1. After any probable failure, the 

cabin temperature-time history may not 

exceed the values shown in Figure 1. 

(Please see Advisory Circular (AC) 

23.1309–1C, pages 10 and 16.) 

2. After any improbable failure, the 

cabin temperature-time history may not 

exceed the values shown in Figure 2. 

(Please see AC 23.1309–1C, pages 9 and 

16.) 

d. Pressurization: In addition to the 

requirements of § 23.841, the following 

revised Special Condition was designed 

to limit high altitude exposure by 

slowing down the depressurization 

event and to mitigate or eliminate acute 

affects of dangerously low atmospheric 

pressure on flight crew and passengers. 

1. For the purposes of this special 

condition, the pressurization system 

includes bleed air, air conditioning, and 

pressure control systems. The 

pressurization system must prevent the 

cabin altitude from exceeding the cabin 

altitude-time history shown in Figure 3 

after each of the following: 

(a) Any probable malfunction or 

failure of the pressurization system. The 

existence of undetected, latent 

malfunctions or failures in conjunction 

with probable failures must be 

considered. 

(b) Any single failure in the 

pressurization system combined with 

the occurrence of a leak produced by a 

complete loss of a door seal element, or 

a fuselage leak through an opening 


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having an effective area 2.0 times the 

effective area, which produces the 

maximum permissible fuselage leak rate 

approved for normal operation, 

whichever produces a more severe leak. 

Note: The ATG Javelin Model 100 proposes 

to use a mechanical canopy seal that is not 

subject to complete loss of the door seal 

element. ATG must still show compliance by 

analysis and/or test a fuselage leak through 

an opening having an effective area 2.0 times 

the effective area that produces the maximum 

permissible fuselage leak rate approved for 

normal operation. 

2. The cabin altitude-time history may 

not exceed that shown in Figure 4 after 

each of the following: 

(a) The maximum pressure vessel 

opening resulting from an initially 

detectable crack propagating for a 

period encompassing four normal 

inspection intervals. Mid-panel cracks 

and cracks through skin-stringer and 

skin-frame combinations must be 

considered. 

(b) The pressure vessel opening or 

duct failure resulting from probable 

damage (failure effect) while under 

maximum operating cabin pressure 

differential due to a tire burst, engine 

rotor burst, loss of antennas or stall 

warning vanes, or any probable 

equipment failure (bleed air, pressure 

control, air conditioning, electrical 

source(s), etc.) that affects 

pressurization. 

3. Complete loss of thrust from all 

engines. In showing compliance with 

paragraphs d.1 and d.2 of these special 

conditions (Pressurization), it may be 

assumed that an emergency descent is 

made by an approved emergency 

procedure. A 5-second crew recognition 

and reaction time must be applied 

between cabin altitude warning and the 

initiation of an emergency descent. 

The additional Special Conditions 

below show full compliance to 

paragraphs d.1. and d.2. and are 

applicable to both aircraft models. 

Special Conditions that are aircraft 

model specific will be noted as Mk–10 

or Mk–20. 

4. A decompression event is 

considered to be a rapid decompression 

event; therefore, the following 

requirements must be met: The airplane 

design must include an auto descent 

feature. The AFM must contain specific 

instructions for its use, including 

considerations for air traffic conditions, 

terrain awareness, annunciation, and 

accessibility to the control(s) for 

automatic initiation of the descent 

sequence by each occupant. 

Note: For the flight evaluation of the rapid 

descent, the test article must have the cabin 

volume representative of what is expected to 

be normal, such that ATG must reduce the 

total cabin volume by that which would be 

occupied by the furnishings and total number 

of people. 

5. ATG must provide flight crew and 

crewmember training requirements, 

including physiological training that 

covers—

(a) Pressure or reverse cycle breathing, 

(b) Rapid decompression training, 

(c) Physical condition with respect to 

the hazards of high altitude rapid 

decompression, and 

(d) Recognition of decompression 

sickness symptoms and the need for 

medical treatment. 

6. The oxygen system must be 

compatible with paragraph e, Oxygen 

Equipment and Supply Special 

Conditions. 

(a) Mk–10: The flight crew and 

passenger(s) are required to use oxygen 

masks for all operating altitudes above 

25,000 feet. 

(b) Mk–20: The flight crew and 

crewmember are required to use oxygen 

masks for all operating altitudes above 

10,000 feet. 

7. ATG will show a means of guarding 

or de-activating the automatic ‘‘auto 

emergency descent’’ mode control in the 

forward or aft cockpit to prevent 

inadvertent descent mode activation. 

Appropriate placards will be required 

for each control device. 

8. ATG will show a means of guarding 

or de-activating the in-flight jettison 

canopy control, canopy fracturing 

system, or any other safety critical 

control device in the forward or aft 

cockpit to prevent inadvertent 

activation. Appropriate placards will be 

required for each control device. 

9. Cabin pressure loss must be 

annunciated as a warning. (See 

Equivalent Level of Safety Findings for 

Cabin Pressurization.) 

10. The AFM will include: 

(a) Mk–10: Require a passenger 

briefing concerning items 4 through 9 

above and the following: 

(i) Seat belts. 

(ii) Emergency exit. 

(iii) Use of quick-donning oxygen 

mask system with a pressure-demand as 

described in paragraph e2, Oxygen 

Equipment and Supply. 

(b) Mk–20: Required flight crew and 

crewmember briefing concerning items 

4 through 10(a) above. 

(i) The flight crew is the pilot and 

crewmember, which means a person 

assigned to perform duty in an aircraft 

during flight time. The Mk–20 poses 

safety concerns for a typical passenger 

since additional training beyond the 

pre-flight briefing may be required to 

use the emergency egress system (i.e., 

ejection seat). Each occupant of the Mk–

20 will be considered as a flight crew or 

crewmember and be required to 

complete the minimum requisite 

training in paragraph d5 before flying on 

the airplane. 

e. Oxygen equipment and supply. 

After several follow-on FAA/ATG 

discussions, the FAA Position Stage 3 

for the Mk–10/Mk–20 Special 

Conditions e.1 and e.2 were revised to 

include quick-donning pressuredemand oxygen mask or an alternate 

helmet mounted oxygen mask for both 

occupants that complies with TSO–C89 

requirements up to 45,000 feet. 

Furthermore, Special Condition e.3 was 

revised to allow a common oxygen 

source with a larger capacity as an 

alternate means or compensating 

feature. 

1. In addition to the requirements of 

§ 23.1441(d), the following applies: A 

quick-donning oxygen mask system 

with a pressure-demand, mask mounted 

regulator that complies with TSO–C89 

requirements up to 45,000 feet must be 

provided for the flight crew. It must be 

shown that each quick-donning mask 

can, with one hand and within 5 

seconds, be placed on the face from its 

ready position, properly secured, sealed, 

and supplying oxygen upon demand. 

Alternately, a helmet mounted oxygen 

mask, panel mounted regulator that 

complies with TSO–C89 requirements 

up to 45,000 feet may be provided to the 

flight crew. 

2. In addition to the requirements of 

§ 23.1443, the following applies: A 

quick-donning oxygen mask system 

with a pressure-demand, mask mounted 

regulator that complies with TSO–C89 

requirements up to 45,000 feet must be 

provided for the passenger or 

crewmember. Alternately, a helmet 

mounted oxygen mask, panel mounted 

regulator that complies with TSO–C89 

requirements up to 45,000 feet may be 

provided to the passenger. 

3. In addition to the requirements of 

§ 23.1445, the following applies: If the 

flight crew and passenger/crewmember 

share a common source of oxygen, a 

means to separately reserve the 

minimum supply required by the flight 

crew must be provided. Alternately, if 

the oxygen system can provide the 

minimum required for the flight crew as 

well as all other occupants, the system 

can have a common source. 

BILLING CODE 4910–13–P 


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Issued in Kansas City, Missouri on 

December 12, 2007. 

James E. Jackson, 

Acting Manager, Small Airplane Directorate, 

Aircraft Certification Service. 

[FR Doc. 07–6129 Filed 12–19–07; 8:45 am] 

BILLING CODE 4910–13–C 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2007–0368; Directorate 

Identifier 2007–NM–050–AD] 

RIN 2120–AA64 

Airworthiness Directives; BAE 

Systems (Operations) Limited Model 

BAe 146–100A, –200A, and –300A 

Series Airplanes 

AGENCY: Federal Aviation 

Administration (FAA), 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: 

Cracking has been found on the centre 

fuselage top aft longeron at Rib ‘0,’ on an inservice aircraft. * * * 

This condition could result in reduced 

structural integrity 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 January 22, 2008. 

ADDRESSES: 

• Federal eRulemaking Portal: Go to 

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

instructions for submitting comments. 

• Fax: (202) 493–2251. 

• Mail: U.S. Department of 

Transportation, Docket Operations, M–

30, West Building Ground Floor, Room 

W12–140, 1200 New Jersey Avenue SE., 

Washington, DC 20590. 

• Hand Delivery: U.S. Department of 

Transportation, Docket Operations, M–

30, West Building Ground Floor, Room 

W12–40, 1200 New Jersey Avenue SE., 

Washington, DC, 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 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 Operations 

office (telephone (800) 647–5527) is in 

the ADDRESSES section. Comments will 

be available in the AD docket shortly 

after receipt. 

FOR FURTHER INFORMATION CONTACT: 

Todd Thompson, Aerospace Engineer, 

International Branch, ANM–116, FAA, 

Transport Airplane Directorate, 1601 

Lind Avenue SW., Renton, Washington 

98057–3356; telephone (425) 227–1175; 

fax (425) 227–1149. 

SUPPLEMENTARY INFORMATION: 

Comments Invited 

We invite you to send any written 

relevant data, views, or arguments about 

this proposed AD. Send your comments 

to an address listed under the 

ADDRESSES section. Include ‘‘Docket No. 

FAA–2007–0368; Directorate Identifier 

2007–NM–050–AD’’ at the beginning of 

your comments. We specifically invite 

comments on the overall regulatory, 

economic, environmental, and energy 

aspects of this proposed AD. We will 

consider all comments received by the 

closing date and may amend this 

proposed AD based on those comments. 

We will post all comments we 

receive, without change, to http:// 

www.regulations.gov, including any 

personal information you provide. We 

will also post a report summarizing each 

substantive verbal contact we receive 

about this proposed AD. 

Discussion 

The European Aviation Safety Agency 

(EASA), which is the Technical Agent 

for the Member States of the European 

Community, has issued EASA 

Airworthiness Directive 2006–0215, 

dated July 14, 2006 (referred to after this 

as ‘‘the MCAI’’), to correct an unsafe 

condition for the specified products. 

The MCAI states: 

Cracking has been found on the centre 

fuselage top aft longeron at Rib ‘0’ on an inservice aircraft. Subsequent investigation has 

indicated that the currently defined 

threshold and repeat inspection period must 

be reduced, and the area of inspection 

expanded for the BAe 146 series 100 and 200. 

For the BAe146 series 300, only the repeat 

inspection period must be reduced, and the 

area of inspection expanded. 

Cracking on the center fuselage top aft 

longeron at Rib ‘0,’ could result in 

reduced structural integrity of the 

airplane. Corrective actions include 

repetitive inspections of the center 

fuselage top aft longeron for cracking 

and repair/replacement if necessary. 

You may obtain further information by 

examining the MCAI in the AD docket. 

Relevant Service Information 

BAE Systems (Operations) Limited 

has issued Service Bulletin ISB.53–173, 

Revision 2, dated March 28, 2006. The 

actions described in this service 

information are intended to correct the 

unsafe condition identified in the 

MCAI. 

FAA’s Determination and Requirements 

of This Proposed AD 

This product has been approved by 

the aviation authority of another 

country, and is approved for operation 

in the United States. Pursuant to our 

bilateral agreement with the State of 

Design Authority, we have been notified 

of the unsafe condition described in the 

MCAI and service information 

referenced above. We are proposing this 

AD because we evaluated all pertinent 

information and determined an unsafe 

condition exists and is likely to exist or 

develop on other products of the same 

type design. 

Differences Between This AD and the 

MCAI or Service Information 

We have reviewed the MCAI and 

related service information and, in 

general, agree with their substance. But 

we might have found it necessary to use 

different words from those in the MCAI 

to ensure the AD is clear for U.S. 

operators and is enforceable. In making 

these changes, we do not intend to differ 

substantively from the information 

provided in the MCAI and related 

service information. 

We might also have proposed 

different actions in this AD from those 

in the MCAI in order to follow FAA 

policies. Any such differences are 

highlighted in a NOTE within the 

proposed AD. 

Costs of Compliance 

Based on the service information, we 

estimate that this proposed AD would 

affect about 1 product of U.S. registry. 

We also estimate that it would take 

about 8 work-hours per product to 

comply with the basic requirements of 

this proposed AD. The average labor 

rate is $80 per work-hour. Based on 

these figures, we estimate the cost of the 

proposed AD on U.S. operators to be 

$640, or $640 per product. 

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 


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