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 Department of Transportation Federal Aviation Administration 14 CFR Part 39
[Docket No. FAA-2010-1204; Directorate Identifier 2010-NM-147-AD]
RIN 2120-AA64
 AGENCY: Federal Aviation Administration (FAA), DOT.
 ACTION: Notice of proposed rulemaking (NPRM).
 SUMMARY: We propose to adopt a new airworthiness directive (AD) for various aircraft equipped with certain ACSS TCAS units. This proposed AD would require upgrading software. This proposed AD results from reports of anomalies with TCAS units during a flight test over a high density airport. The TCAS units dropped several reduced surveillance aircraft tracks because of interference limiting. We are proposing this AD to prevent TCAS units from dropping tracks, which could compromise separation of air traffic and lead to subsequent mid-air collisions.
 DATES: We must receive comments on this proposed AD by February 11, 2011.
 ADDRESSES: You may send comments by any of the following methods: *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 W12-140, 1200 New Jersey Avenue, SE., Washington, DC 20590, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. For service information identified in this proposed AD, contact Aviation Communication & Surveillance Systems, LLC, 19810 North 7th Avenue, Phoenix, Arizona 85027-4741; telephone (623) 445-7040; fax (623) 445-7004; e-mail 
                        *acss.orderadmin@L-3com.com;*
                         Internet 
                        *http://www.acss.com.*
                         You may review copies of the referenced service information at 
                        ( print page 81513)
                        the FAA, Transport Airplane Directorate, 1601 Lind, Avenue, SW., Renton, Washington. For information on the availability of this material at the FAA, call 425-227-1221. Examining the AD Docket You may examine the AD docket on the Internet at 
                    *http://www.regulations.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 800-647-5527) is in the 
                    **ADDRESSES**
                     section. Comments will be available in the AD docket shortly after receipt.
 FOR FURTHER INFORMATION CONTACT: Abby Malmir, Aerospace Engineer, Systems and Equipment Branch, ANM-130L, FAA, Los Angeles Aircraft Certification Office (ACO), 3960 Paramount Boulevard, Lakewood, California 90712-4137; telephone (562) 627-5351; fax (562) 627-5210.


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-2010-1204; Directorate Identifier 2010-NM-147-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 because of 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 We have received reports of anomalies with the Aviation Communication & Surveillance Systems (ACSS) Traffic Alert and Collision Avoidance System (TCAS) units during a flight test over a high density airport. The TCAS units dropped several reduced surveillance aircraft tracks because of interference limiting. When the TCAS unit interrogated aircraft in a high density airport area, some of the targets disappeared from the cockpit display or were not recognized. One occurrence of dropped tracks occurred for 30 to 40 seconds of a 90-minute flight segment. This condition, if not corrected, could lead to possible loss of separation of air traffic and possible mid-air collision. Relevant Service Information We have reviewed the ACSS service information specified in the following table. The service information describes procedures for upgrading software for the ACSS TCAS to improve tracking of nearby Mode-S intruders in high density environments. Relevant Service Information
ATA Service Bulletin No.
ACSS Publication No.
Date4066010-34-6036
8008230-001
May 25, 2010.7517900-34-6040
8008229-001
May 12, 2010.7517900-34-6041
8008231-001
May 24, 2010.7517900-34-6042
8008236-001
May 27, 2010.9000000-34-6016
8008233-001
June 4, 2010.9000000-34-6017
8008234-001
June 4, 2010.9000000-34-6018
8008238-001
June 4, 2010.9003000-34-6006
8008235-001
June 4, 2010.9003500-34-6014
8008221-001
May 27, 2010.9003500-34-6015
8008222-001
May 27, 2010.9003500-34-6016
8008223-001
May 27, 2010.
 FAA's Determination and Requirements of This Proposed AD We are proposing this AD because we evaluated all relevant information and determined the unsafe condition described previously is likely to exist or develop in other products of these same type designs. This proposed AD would require accomplishing the actions specified in the service information described previously. Costs of Compliance We estimate that this proposed AD would affect 9,000 airplanes of U.S. registry. We also estimate that it would take about 2 work-hours per product to comply with this proposed AD. The average labor rate is $85 per work-hour. Required parts would cost up to $2,870 per product. Based on these figures, we estimate the cost of this proposed AD to the U.S. operators to be up to $27,360,000, or up to $3,040 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 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. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action. Regulatory Findings We determined that this proposed AD would not have federalism implications under Executive Order 13132. This proposed AD 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. *For the reasons discussed above, I certify this proposed regulation:* 1. Is not a “significant regulatory action” under Executive Order 12866,
                    ( print page 81514) 2. Is not a “significant rule” under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979), and 3. Will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act. You can find our regulatory evaluation and the estimated costs of compliance in the AD Docket. List of Subjects in 14 CFR Part 39 Air transportation
Aircraft
Aviation safety
Incorporation by reference
Safety
 The Proposed Amendment Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 14 CFR part 39 as follows: PART 39—AIRWORTHINESS DIRECTIVES 1. The authority citation for part 39 continues to read as follows: Authority:
                        49 U.S.C. 106(g), 40113, 44701. § 39.13
  2. The FAA amends § 39.13 by adding the following new AD: **Aviation Communication & Surveillance Systems, LLC:**
                                 Docket No. FAA-2010-1204; Directorate Identifier 2010-NM-147-AD. Comments Due Date (a) We must receive comments by February 11, 2011. Affected ADs (b) None. Applicability (c) This AD applies to Aviation Communication & Surveillance Systems (ACSS) Traffic Alert and Collision Avoidance System (TCAS) units with the part numbers (P/Ns) specified in the ACSS service bulletins identified in Table 1 of this AD, as installed on, but not limited to, various transport and small airplanes, certificated in any category. Table 1—Applicable Service Bulletins
ATA Service Bulletin No.
ACSS 
                                         Publication No.
Date4066010-34-6036
8008230-001
May 25, 2010.7517900-34-6040
8008229-001
May 12, 2010.7517900-34-6041
8008231-001
May 24, 2010.7517900-34-6042
8008236-001
May 27, 2010.9000000-34-6016
8008233-001
June 4, 2010.9000000-34-6017
8008234-001
June 4, 2010.9000000-34-6018
8008238-001
June 4, 2010.9003000-34-6006
8008235-001
June 4, 2010.9003500-34-6014
8008221-001
May 27, 2010.9003500-34-6015
8008222-001
May 27, 2010.9003500-34-6016
8008223-001
May 27, 2010.
 Subject (d) Air Transport Association (ATA) of America Code 34: Navigation. Unsafe Condition (e) This AD results from reports of anomalies with TCAS units during a flight test over a high density airport. The TCAS units dropped several reduced surveillance aircraft tracks because of interference limiting. The Federal Aviation Administration is issuing this AD to prevent TCAS units from dropping tracks, which could compromise separation of air traffic and lead to subsequent mid-air collisions. Compliance (f) You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done. Upgrade Software (g) Within 48 months after the effective date of this AD, upgrade software for the ACSS TCAS, in accordance with the Accomplishment Instructions of the applicable ACSS service bulletin identified in Table 1 of this AD. Note 1: ACSS Publication Number 8008233-001, dated June 4, 2010, ATA Service Bulletin 9000000-34-6016, contains three part numbers (P/Ns 9000000-10007, -20007, and -55007) which were never produced. Alternative Methods of Compliance (AMOCs) (h)(1) The Manager, Los Angeles Aircraft Certification Office (ACO), FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. Send information to 
                                *Attn:*
                                 Abby Malmir, Aerospace Engineer, Systems and Equipment Branch, ANM-130L, FAA, Los Angeles ACO, 3960 Paramount Boulevard, Lakewood, California 90712-4137; telephone (562) 627-5351; fax (562) 627-5210. (2) To request a different method of compliance or a different compliance time for this AD, follow the procedures in 14 CFR 39.19. Before using any approved AMOC on any airplane to which the AMOC applies, notify your principal maintenance inspector (PMI) or principal avionics inspector (PAI), as appropriate, or lacking a principal inspector, your local Flight Standards District Office. The AMOC approval letter must specifically reference this AD.
 Issued in Renton, Washington, on December 13, 2010. Ali Bahrami, Manager, Transport Airplane Directorate, Aircraft Certification Service.


[FR Doc. 2010-32658 Filed 12-27-10; 8:45 am] BILLING CODE 4910-13-P