[Federal Register Volume 70, Number 106 (Friday, June 3, 2005)]
[Notices]
[Page 32699]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 05-11114]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration


Proposed revision: Technical Standard Order (TSO)-C128a, 
Equipment That Prevent Blocked Channels Used in Two-Way Radio 
Communications Due To Unintentional Transmissions

AGENCY: Federal Aviation Administration (DOT).

ACTION: Notice of availability and request for public comment.

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SUMMARY: This notice announces the availability of and requests 
comments on a proposed Technical Standard Order (TSO)-C128a, Equipment 
That Prevent Blocked Channels Used in Two-way Radio Communications Due 
To Unintentional Transmissions. The TSO manufacturers seeking a TSO 
authorization or letter of design approval what minimum performance 
standards (MPS) their transmitter radio equipment to prevent blocked 
channels must first meet for approval and identification with the 
applicable TSO markings.

DATES: Submit comments on or before July 5, 2005.

ADDRESSES: Send all comments on the proposed revised technical standard 
order to: Federal Aviation Administration (FAA), Aircraft Certification 
Service, Aircraft Engineering Division, Avionic Systems Branch, Room 
815, AIR-130, 800 Independence Avenue, SW., Washington, DC 20591. Attn: 
Mr. Thomas Mustach. Or deliver comments to: Federal Aviation 
Administration, Room 815, 800 Independence Avenue, SW., Washington, DC 
20591.

FOR FURTHER INFORMATION CONTACT: Mr. Thomas Mustach, AIR-130, Room 815, 
Federal Aviation Administration, Aircraft Certification Service, 
Aircraft Engineering Division, 800 Independence Avenue, SW., 
Washington, DC 20591. Telephone (425) 227-1935, FAX: (425) 227-1181. 
Or, via e-mail at: [email protected].

SUPPLEMENTARY INFORMATION:

Comments Invited

    You are invited to comment on the proposed TSO listed in this 
notice by submitting such written data, views, or arguments to the 
address listed above. Your comments should identify ``Comments to 
Proposed TSO-C128a.`` You may examine all comments received on the 
proposed revised TSO before and after the comment closing date, at the 
FAA Headquarters Building, Room 815, 800 Independence Avenue, SW., 
Washington, DC 20591, weekdays except Federal holidays, between 8:30 
a.m. and 4:30 p.m. The Director of the Aircraft Certification Service 
will consider all communications received on or before the closing date 
before issuing the final revised TSO.

Background

    This proposed TSO-C128a includes the latest TSO boilerplate wording 
and format, to include a Functionality definition used to specify the 
Failure Hazard Classification and invokes environmental conditions and 
test procedures specified in RTCA/DO-160E, Environmental Conditions and 
Test Procedures for Airborne Equipment, dated December 9, 2004. The 
proposed TSO provides a minimum operational performance standard for 
equipment intended to prevent blocked frequencies used in air traffic 
control (ATC) two-way radio communication due to unintentional 
transmissions by aircraft transmitters. Equipment covered by this 
proposed TSO is primarily intended for Aeronautical Operational Control 
(AOC) and Air Traffic Services (ATS) safety communications.

How To Obtain Copies

    You may get a copy of the proposed TSO from the Internet at: http://av-info.faa.gov/tso/Tsopro/Proposed.htm. See section entitled for 
further information contact for the complete address if requesting a 
copy by mail. You may inspect the RTCA document at the FAA office 
location listed under addresses. Note however, RTCA documents are 
copyrighted and may not be reproduced without the written consent of 
RTCA, Inc. You may purchase copies of RTCA, Inc. documents from: RTCA, 
Inc., 1828 L Street, NW., Suite 815, Washington, DC 20036, or directly 
from their Web site: http://www.rtca.org/.

    Issued in Washington, DC, on May 26, 2005.
Susan J.M. Cabler,
Assistant Manager, Aircraft Engineering Division, Aircraft 
Certification Service.
[FR Doc. 05-11114 Filed 6-2-05; 8:45 am]
BILLING CODE 4910-13-M