[Federal Register Volume 64, Number 102 (Thursday, May 27, 1999)]
[Proposed Rules]
[Pages 28770-28771]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-13233]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Parts 91, 121, and 135
Terrain Awareness and Warning System
AGENCY: Federal Aviation Administration (DOT).
ACTION: Notice of availability for public comment.
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SUMMARY: This document announces the availability of and requests
comments on a revised proposed Technical Standard Order (TSO) C151,
Terrain Awareness and Warning System (TAWS). The proposed TSO
prescribes the minimum operational performance standards that TAWS must
meet to be identified with the applicable TSO marking.
DATES: Comments submitted must be received on or before July 9, 1999.
ADDRESSES: Send all comments on the proposed technical standard order
to: Federal Aviation Administration (FAA), Aircraft Certification
Service, Aircraft Engineering Division, Avionic Systems Branch, AIR-
130, 800 Independence Avenue, SW., Washington, DC 20591. Or deliver
comments to: Federal Aviation Administration, Room 815, 800
Independence Avenue, SW., Washington, DC 20591.
FOR FURTHER INFORMATION CONTACT: Michelle Swearingen, Federal Aviation
Administration (FAA), Aircraft Certification Service, Aircraft
Engineering Division, Avionic Systems Branch, AIR-130, 800 Independence
Avenue, SW., Washington, DC 20591, Telephone: (202) 267-3817, FAX: 267-
5340.
SUPPLEMENTARY INFORMATION:
Comments Invited
Interested persons are invited to comment on the proposed TSO
listed in this document by submitting such written data, views, or
arguments, as they desire, to the aforementioned specified address.
Comments must be marked ``Comments to TSO C151.'' Comments received on
the proposed technical standard order may be examined, both before and
after the closing date, in Room 815, FAA Headquarters Building (FOB-
10A), 800 Independence Avenue, SW., Washington, DC 20591, weekdays
except Federal holidays, between 8:30 a.m. and 4:30 p.m. All
communications received on or before the closing date for comments
specified will be considered by the Director of the Aircraft
Certification Service before issuing the final TSO.
Background
The FAA is developing a new technical standard order, TSO-C151,
Terrain Awareness and Warning System. This TSO will prescribe the
minimum operational performance standards that TAWS equipment must meet
to be identified with the TSO-C151 Class A or Class B marking. This is
the second opportunity for the public and the industry to review and
comment upon the proposed TSO before the FAA publishes it as a final
document. The FAA is giving this second opportunity for the following
two reasons.
First, the FAA has revised significantly the proposed TSO as a
result of public comments. On November 4, 1998, the FAA published in
the Federal Register (63 FR 59494, November 4, 1998) a notice of
availability for public comment that announced the availability of and
requested comments on proposed TSO-C151, Terrain Awareness and Warning
System. In response to the TSO notice of availability, commenters
submitted a large number of suggested changes, approximately 300, to
the proposed TSO. In trying to be as flexible and as accommodating as
technically feasible, the FAA accepted and included most of the
suggested changes. As a result, the current proposed version is
significantly different than what was originally proposed with the
initial notice of availability.
[[Page 28771]]
Second, the FAA has included two classes of TAWS equipment in the
current version of the proposed TSO. On August 26, 1998, the FAA
published in the Federal Register (63 FR 45628, August 26, 1998) a
notice of proposed rulemaking (NPRM). That NPRM proposed to amend 14
CFR part 91, General Operating and Flight Rules, by adding new rules
that prohibit the operation of certain airplanes unless those airplanes
are equipped with a TAWS that meets the requirements of the proposed
TSO-C151. In response to the NPRM, the FAA received over 250 comments.
Having reviewed the comments, the FAA is making changes to its proposed
rule based on those comments. One significant change is to develop two
classes of TAWS equipment, known as Class A and Class B. TSO-C151 Class
A equipment will be required for all turbine powered airplanes operated
under 14 CFR part 121 and for turbine powered airplanes configured for
10 or more passenger seating operating under 14 CFR part 135. TSO-C151
Class B equipment will be the minimum requirement for turbine powered
airplanes configured with 6 or more passenger seats operating under 14
CFR part 91 and for turbine powered airplanes configured with 6 to 9
passenger seating operating under 14 CFR part 135. The proposed TSO-
C151 has been revised to include the airworthiness requirements for
both Class A and Class B equipment. The original proposed TSO
associated with the initial notice of availability did not include two
classes of TAWS equipment.
Both classes of equipment--Class A and Class B--include the TAWS
features of comparing airplane position information to an on board
terrain database then providing appropriate caution and warning alerts
if necessary. The Class A equipment includes, in addition to the TAWS
features, ground proximity warning system (GPWS) functions. There
currently are International Civil Aviation Organizations (ICAO) and FAA
(14 CFR parts 121 & 135) requirements for all part 121 and certain part
135 airplanes to carry GPWS. Therefore Class A equipment includes both
TAWS and GPWS features. The existing 14 CFR parts 121 and 135 rules for
GPWS are being revised to make them compatible with the proposed new 14
CFR part 91 TAWS rule. Class B equipment is the basic TAWS equipment
and is required as minimum equipment by the new FAR Part 91 TAWS rule.
Class A equipment, which includes both TAWS and GPWS, is required by
the revised part 121 and part 135 rules for those airplanes that
currently must carry GPWS. The FAA is requiring one level of safety for
TAWS while still maintaining existing ICAO and FAA GPWS requirements
for turbine-powered commercial airplanes. This TSO will be the means to
obtain FAA approval of TAWS product(s).
How To Obtain Copies
A copy of the revised proposed TSO-C151 may be obtained via
Internet (http://www.faa.gov/avr/air/airhome.htm) or on requests from
the individual listed under FOR FURTHER INFORMATION CONTACT.
The revised proposed TSO references several RTCA, Inc. documents
that contain specific requirements related to the TSO. RTCA Document
No. DO-161A, ``Minimum Performance Standards--Airborne Ground Proximity
Warning Equipment,'' dated May 27, 1976; DO-160D, ``Environmental
Conditions and Test Procedures for Airborne Equipment,'' dated July 29,
1997; DO-178B, ``Software Considerations in Airborne Systems and
Equipment Certification,'' dated December 1, 1992; and DO-200A,
``Preparation, Verification and Distribution of User-Selectable
Navigation Data Bases,'' dated November 28, 1998, may be purchased from
the RTCA Inc., 1140 Connecticut Avenue, NW., Suite 1020, Washington, DC
22036. Copies of the RTCA documents may be inspected at the location
specified under ADDRESSES. However, those documents are copyrighted and
may not be copied without the written consent of RTCA, Inc.
Issued in Washington, DC, on May 19, 1999.
James C. Jones,
Manager, Aircraft Engineering Division, Aircraft Certification Service.
[FR Doc. 99-13233 Filed 5-26-99; 8:45 am]
BILLING CODE 4910-13-M
