[Federal Register Volume 63, Number 213 (Wednesday, November 4, 1998)]
[Proposed Rules]
[Pages 59494-59495]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-29492]


 ========================================================================
 Proposed Rules
                                                 Federal Register
 ________________________________________________________________________
 
 This section of the FEDERAL REGISTER contains notices to the public of 
 the proposed issuance of rules and regulations. The purpose of these 
 notices is to give interested persons an opportunity to participate in 
 the rule making prior to the adoption of the final rules.
 
 ========================================================================
 

  Federal Register / Vol. 63, No. 213 / Wednesday, November 4, 1998 / 
Proposed Rules  

[[Page 59494]]


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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 notice announces the availability of and requests 
comments on proposed Technical Standard Order (TSO) C151, Terrain 
Awareness and Warning System (TAWS). The proposed TSO prescribes the 
minimum operational performance standards that a TAWS must meet to be 
identified with the applicable TSO marking.

DATES: Comments submitted must identify the TSO file number and be 
received on or before January 26, 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: (202) 267-5340.

SUPPLEMENTARY INFORMATION: 

Comments Invited

    Interested person are invited to comment on the proposed TSO listed 
in this notice by submitting such written data, views, or arguments, as 
they desire, to the aforementioned specified address. Comments received 
on the proposed technical standard order may be examined, before 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 above will be 
considered by the Director of the Aircraft Certification Service before 
issuing the final TSO.

Background

    The Federal Aviation Administration (FAA) has proposed issuing 
operating rules that would prohibit operation of turbine-powered U.S. 
registered airplanes type certificated to have six or more passenger 
seats, exclusive of pilot and copilot seating, unless that airplane is 
equipped with an FAA-approved terrain awareness and warning system 
(also referred to as an enhanced ground proximity warning system) (63 
FR 45628, August 26, 1998). That proposal would affect aircraft 
operated under parts 91, 121 and 135. Because operators under part 125 
and operators of U.S. registered airplanes under part 129 must comply 
with part 91, they would also have to meet this proposed requirement.
    The change is needed because there have been several accident 
investigations and studies that have shown a need to expand the safety 
benefits of ground proximity warning systems to certain additional 
operations. In addition, the investigations and studies have shown that 
there is a need to increase the warning times and situational awareness 
of flight crews to decrease the risk of controlled flight into terrain 
accidents.
    Currently, the FAA approves the manufacture and installation of 
Ground Proximity Warning Systems (GPWS) through Technical Standard 
Orders. Section 121.360 of 14 CFR requires the use of a GPWS meeting 
TSO-C92, which has been reissued as TSO-C92a, TSO-C92b, and TSO-C92c. 
The FAA does not intend to revise TSO-C92c to include TAWS 
requirements.
    Instead, the FAA is developing and plans to issue a new and 
separate TSO for TAWS. The new TSO-C151, TAWS, is being developed 
through the FAA TSO process that allows for public comments. Any person 
desiring to review and comment on the draft TSO-C151 may obtain a copy 
of the draft TSO-C151 from the person mentioned in the section entitled 
FOR FURTHER INFORMATION CONTACT. This TSO would be the means to obtain 
FAA approval of the TAWS product.
    The standards of the TSO apply to equipment intended to provide the 
flight crew with both aural and visual alerts and terrain information 
on a display to aid in preventing an inadvertent controlled flight into 
terrain (CFIT) event. The TAWS includes: (a) a terrain display, (b) 
terrain awareness and alerting functions which use position information 
provided by either a suitable internal position sensor or an on-board 
area navigational system and an on-board terrain database, and (c) 
ground proximity detection and alerting functions that are described in 
the TSO as modes 1-6.
    Comments submitted in response to this TSO notice will also be 
included in the docket for the TAWS NPRM. A preliminary review of 
comments submitted in response to the NPRM indicates that several 
commenters are very interested in the provisions of the proposed TAWS 
TSO. Accordingly, to the extent that commenters want to clarify or 
supplement their comments submitted to the NPRM docket, they should so 
identify those clarifying and supplementary comments submitted to the 
TSO-C151 docket.

How To Obtain Copies

    A copy of the proposed TSO-C151 may be obtained via Internet 
(http://www.faa.gov/avr/air/100home.htm) or on request from the office 
listed under For Further Information Contact. 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 1992; and DO-200, ``Preparation, 
Verification and Distribution of User-Selectable Navigation Data 
Bases,'' dated November 28, 1988, 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 ADDRESSES listed above. 
However, those documents are copyrighted and may not

[[Page 59495]]

be copied without the written consent of RTCA, Inc.

    Issued in Washington, DC, on October 26, 1998.
James C. Jones,
Manager, Aircraft Engineering Division, Aircraft Certification Service.
[FR Doc. 98-29492 Filed 11-3-98; 8:45 am]
BILLING CODE 4910-13-M