Air traffic operating and flight rules, etc.: Terrain awareness and warning system,

[Federal Register: May 27, 1999 (Volume 64, Number 102)]

[Proposed Rules]

[Page 28770-28771]

From the Federal Register Online via GPO Access [wais.access.gpo.gov]

[DOCID:fr27my99-21]

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.

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. 99-13233Filed5-26-99; 8:45 am]

BILLING CODE 4910-13-M