[Federal Register Volume 69, Number 80 (Monday, April 26, 2004)]
[Rules and Regulations]
[Pages 22386-22387]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-9104]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2002-NE-32-AD; Amendment 39-13586; AD 2004-08-16]
RIN 2120-AA64


Airworthiness Directives; NARCO Avionics Inc. AT150 Transponders

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for 
certain serial numbers (SNs) of NARCO Avionics Inc. AT150 transponders. 
This AD requires modification to the transponder by adding a resistor 
and transistor to the circuit board. This AD results from reports of 
AT150 transponders not recognizing and responding properly to Mode S 
interrogations from Mode S ground stations and Traffic Alert and 
Collision Avoidance System (TCAS-II) airborne equipment. We are issuing 
this AD to prevent loss of aircraft airspace separation and the 
possibility of mid-air collision.

DATES: This AD becomes effective June 1, 2004. The Director of the 
Federal Register approved the incorporation by reference of certain 
publications listed in the regulations as of June 1, 2004.

ADDRESSES: You can get the service information identified in this AD 
from NARCO Avionics Inc., 270 Commerce Drive, Fort Washington, PA 
19034; telephone (215) 643-2905; fax (215) 643-0197.
    You may examine the AD docket, by appointment, at the FAA, New 
England Region, Office of the Regional Counsel, 12 New England 
Executive Park, Burlington, MA. You may examine the service 
information, by appointment, at the FAA, New England Region, Office of 
the Regional Counsel, 12 New England Executive Park, Burlington, MA; or 
at the Office of the Federal Register, 800 North Capitol Street, NW., 
suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Balram Rambrich, Aerospace Engineer, 
New York Aircraft Certification Office, FAA, Engine and Propeller 
Directorate, 10 Fifth Street, 3rd floor, Valley Stream, NY 11581-1200; 
telephone (516) 256-7507; fax (516) 256-2716.

SUPPLEMENTARY INFORMATION: The FAA proposed to amend 14 CFR Part 39 
with a proposed airworthiness directive (AD). The proposed AD applies 
to certain SNs of NARCO Avionics Inc. AT150 transponders. We published 
the proposed AD in the Federal Register on February 20, 2003 (68 FR 
816). That action proposed to require:
     For transponders not modified in accordance with 
NARCO Avionics Inc. Service Bulletin (SB) AT150 No. 1, dated July 29, 
1977, modification of ``Chassis Level A'' transponders, serial numbers 
10000 through 12598 inclusive, by adding a resistor and transistor to 
the circuit board, changing transponder to ``Chassis Level B'', and 
transponder testing after the modification; and
     For transponders modified in accordance with 
NARCO Avionics Inc. SB No. AT150 No. 1, dated July 29, 1977, changing 
transponder to ``Chassis Level B'', and transponder testing.

Comments

    We provided the public the opportunity to participate in the 
development of this AD. We have considered the comments received.

Request To Correct the Discussion Wording

    One commenter, the manufacturer, requests that we correct the 
discussion section in the proposal. As written, the discussion states 
that the manufacturer determined that ``Chassis Level A'' AT150 
transponders have a design error, which causes the P4 pulse not to be 
presented, causing the transponders to shut down. The commenter states 
that the AT150 transponder met all the requirements of technical 
standard order (TSO)-C-74C at the time of design. The commenter also 
states that NARCO Avionics Inc. SB AT150 No. 1, dated July 29, 1977, 
was issued because original design AT150 transponders did not work 
properly with particular Tele Instruments Corporation (TIC) and bench 
test equipment. Also, the commenter states that the incorporation of 
NARCO Avionics Inc. SB No. AT150 No. 1, dated July 29, 1977, resolves 
the P4 problem, which came about years after the original design. The 
implementation of the P4 pulse was an FAA requirement.
    We partially agree. We agree that this problem in its entirety is 
not a design error because we implemented the P4 pulse requirement 
after approval of TSO-C-74C and because the problem with NARCO AT150 
transponders was discovered during the P4 pulse testing. However, the 
AT150 transponder did not work properly with the TIC ramp and bench 
test equipment. The final rule does not repeat the discussion 
information found in the proposal. No changes to the final rule are 
made based on this comment.

Request To Correct Service Information Fax Number

    One commenter, the manufacturer, requests that we correct the 
service information fax number to read (215) 643-0197.
    We agree. We corrected the fax number in the final rule.

Request To Correct Part Numbers

    Two commenters request that we correct the part numbers for the 
transistor and resistor, which are transposed in the proposal.
    We agree. We corrected the part numbers in the final rule.

[[Page 22387]]

Aircraft Models List

    Three commenters state that the applicability section should not 
include a list of any particular aircraft models because the unsafe 
condition identified in the proposal involves the design of the 
transponder, not the aircraft. The commenters suggest using a generic 
statement, such as ``all general aviation aircraft'' rather than 
listing any specific aircraft models.
    We do not agree. The commenters all start from the incorrect 
premise that the listing of aircraft in the proposed AD affects the 
applicability of the AD. The listing is provided only as a guide to 
operators as to some of the types of aircraft on which these 
transponders may be found. The AD applies to the transponder regardless 
of the installation, even if installed in an aircraft not found in the 
list. The list is provided for informational purposes only. However, 
because the presence of the list is causing more confusion than 
benefits we deleted the list from the applicability paragraph.

AD Should Not Be Issued Through Engine & Propeller Directorate

    One commenter states that the FAA should not issue this AD through 
the Engine & Propeller Directorate.
    We do not agree. While each engineering Directorate within the 
Aircraft Certification Service has an area of concentration, all of the 
Directorates have the expertise to deal with avionics issues, such as 
transponders. For example, the Rotorcraft Directorate issued an AD 
against Terra Corporation transponders in 1994, and recently the Small 
Aircraft Directorate issued an AD in December 2003 against Garmin 
transponders. Because we handle unsafe conditions that result from 
appliances, such as transponders, geographic basis, the Engine & 
Propeller Directorate appropriately issued the proposal and the AD in 
this case.

Conclusion

    We have carefully reviewed the available data, including the 
comments received, and determined that air safety and the public 
interest require adopting the AD with the changes described previously. 
We have determined that these changes will neither increase the 
economic burden on any operator nor increase the scope of the AD.

Regulatory Findings

    We have determined that this AD will not have federalism 
implications under Executive Order 13132. This AD will 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 that this AD:
    (1) Is not a ``significant regulatory action'' under Executive 
Order 12866;
    (2) Is not a ``significant rule'' under 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.
    We prepared a summary of the costs to comply with this AD and 
placed it in the AD Docket. You may get a copy of this summary by 
sending a request to us at the address listed under ADDRESSES. Include 
``AD Docket No. 2002-NE-32-AD'' in your request.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

0
Accordingly, under the authority delegated to me by the Administrator, 
the Federal Aviation Administration amends 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0
1. The authority citation for part 39 continues to read as follows:


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


Sec.  39.13  [Amended]

0
2. The FAA amends Sec.  39.13 by adding the following new airworthiness 
directive (AD):

2004-08-16 NARCO Avionics Inc. AT150 Transponders: Amendment 39-
13586. Docket No. 2002-NE-32-AD.

Effective Date

    (a) This AD becomes effective June 1, 2004.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to NARCO Avionics Inc. AT150 transponders 
with ``Chassis Level A'', serial numbers (SNs) 10000 through 12598 
inclusive.

Unsafe Condition

    (d) This AD results from reports of AT150 transponders not 
recognizing and responding properly to Mode S interrogations from 
Mode S ground stations and Traffic Alert and Collision Avoidance 
System (TCAS-II) airborne equipment. The actions specified in this 
AD are intended to prevent loss of aircraft airspace separation and 
the possibility of mid-air collision.

Compliance

    (e) Compliance with this AD is required as indicated, unless 
already done.

Transponders Not Modified in Accordance With Service Bulletin AT150 No. 
1

    (f) For AT150 transponders with a SN listed in this AD that are 
not modified in accordance with NARCO service bulletin (SB) No. 
AT150 No. 1, dated July 29, 1977, within six months after the 
effective date of this AD, do the following:
    (1) Install resistor part number (P/N) 312180102 and transistor 
P/N 755610028; and
    (2) Change transponder to ``Chassis Level B''; and
    (3) Test transponders in accordance with the Corrective Action, 
Testing the Modification, and Return to Service paragraphs of NARCO 
SB No. AT150 No. 6, dated January 31, 2003.

Transponders Modified in Accordance With Service Bulletin AT150 No. 1

    (g) For AT150 transponders with a SN listed in this AD, that are 
modified in accordance with NARCO SB No. AT150 No. 1, dated July 29, 
1977, do the following:
    (1) Within six months after the effective date of this AD, 
change transponder to ``Chassis Level B''; and
    (2) Test transponders in accordance with the Testing the 
Modification paragraph of NARCO SB No. AT150 No. 6, dated January 
31, 2003; and
    (3) Perform a bench test to the transponder before returning it 
to service. Information on bench testing can be found in AT150 
Manual P/N 03606-0600.

Alternative Methods of Compliance

    (h) The Manager, New York Aircraft Certification Office, has the 
authority to approve alternative methods of compliance for this AD 
if requested using the procedures found in 14 CFR 39.19.

Material Incorporated by Reference

    (i) You must use NARCO SB No. AT150 No. 6, dated January 31, 
2003, to perform the testing required by this AD. The Director of 
the Federal Register approved the incorporation by reference of this 
service bulletin in accordance with 5 U.S.C. 552(a) and 1 CFR part 
51. You can get a copy from NARCO Avionics Inc., 270 Commerce Drive, 
Fort Washington, PA 19034; telephone (215) 643-2905; fax (215) 643-
0197. You can review copies at the FAA, New England Region, Office 
of the Regional Counsel, 12 New England Executive Park, Burlington, 
MA; or at the Office of the Federal Register, 800 North Capitol 
Street, NW., suite 700, Washington, DC.

Related Information

    (j) None.

    Issued in Burlington, Massachusetts, on April 16, 2004.
Robert Guyotte,
Acting Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 04-9104 Filed 4-23-04; 8:45 am]
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