Airworthiness Directives; Trimble or FreeFlight Systems 2101 I/O Approach Plus Global Positioning System (GPS) Navigation Systems

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

This document proposes adopting a new airworthiness directive (AD) for the Trimble or FreeFlight Systems 2101 I/O Approach Plus global positioning system (GPS) navigation system (2101 I/O Approach Plus system). The AD would require a software upgrade for this system. This proposal is prompted by an incident that led to the discovery of several annunciation errors with the 2101 I/O Approach Plus system. The actions specified by the proposed AD are intended to prevent a pilot from making an unsafe decision based on erroneous information provided by the 2101 I/O Approach Plus system, which could result in loss of control of the aircraft.

DATES:

Comments must be received on or before September 11, 2007.

ADDRESSES:

Use one of the following addresses to submit comments on this proposed AD:

• DOT Docket Web site: Go to http://dms.dot.gov and follow the instructions for sending your comments electronically;
• Government-wide rulemaking Web site: Go to http://www.regulations.gov and follow the instructions for sending your comments electronically;
• Mail: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE., Washington, DC 20590;
• Hand Delivery: Deliver to the “Mail” address between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays; or
• Fax: (202) 493-2251.

You may get the service information identified in this proposed AD from FreeFlight Systems, 3700 IH 35, Waco, Texas, USA, 76706, or by calling (254) 662-0000.

You may examine the comments to this proposed AD in the AD docket on the Internet at http://dms.dot.gov.

FOR FURTHER INFORMATION CONTACT:

Sung-Hui Cavazos, Aviation Safety Engineer, FAA, Rotorcraft Directorate, Special Certification Office, Fort Worth, Texas 76193-0170, telephone (817) 222-5142, fax (817) 222-5785.

SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to submit any written data, views, or arguments regarding this proposed AD. Send your comments to the address listed under the caption ADDRESSES. Include the docket number “FAA-2007-28689, Directorate Identifier 2006-SW-17-AD” at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of the proposed AD. We will consider all comments received by the closing date and may amend the proposed AD in light of those comments.

We will post all comments we receive, without change, to http://dms.dot.gov,, including any personal information you provide. We will also post a report summarizing each substantive verbal contact with FAA personnel concerning this proposed rulemaking. Using the search function of our docket web site, you can find and read the comments to any of our dockets, including the name of the individual who sent or signed the comment. You may review the DOT's complete Privacy Act Statement in the Federal Register published on April 11, 2000 (65 FR 19477-78) or you may visit http://dms.dot.gov.

Examining the Docket

You may examine the docket that contains the proposed AD, any comments, and other information in person at the Docket Management System (DMS) Docket Office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The Docket Office (telephone 1-800-647-5527) is located in Room W12-140 on the ground floor of the West Building, 1200 New Jersey Avenue, SE., Washington, DC. Comments will be available in the AD docket shortly after the DMS receives them.

Discussion

This document proposes adopting a new AD for the 2101 I/O Approach Plus system that would require a software upgrade. This proposal is prompted by an incident involving a Federal Republic of Germany military helicopter that led to the discovery of the following system malfunctions:

• Under certain conditions, when the system enters Dead Reckoning (DR) mode, the navigation and Super flags are removed from the display; however, the DR message and associated message light annunciation may fail to illuminate;
• The navigation and Super flags may not be removed from the display as required during approach mode after loss of a Receiver Autonomous Integrity Monitor (RAIM) condition; and
• When a RAIM error occurs (detects a satellite failure) and the system is unable to exclude the affected satellite, the unit may fail to enter DR mode and may fail to remove the navigation and Super flags from the display.

These malfunctions could result in the following unsafe conditions:

• System could fail when interfaced with Terrain Awareness Warning System (TAWS) and the TAWS can fail to annunciate terrain alerts;
• System could provide misleading heading information; or
• System may provide erroneous navigation fault annunciations.

The actions specified by the proposed AD are intended to prevent a pilot from making an unsafe decision based on erroneous information provided by the 2101 I/O Approach Plus system, which could result in loss of control of the aircraft.

These unsafe conditions are likely to exist or develop on any aircraft with a 2101 I/O Approach Plus system installed. Therefore, the proposed AD would require, within 180 days after the effective date of the AD for aircraft approved for instrument flight rule (IFR) flight, or 270 days after the effective date of the AD for aircraft approved for visual flight rule (VFR) flight, upgrading the 2101 I/O Approach Plus system software. This AD is applicable to the units that currently have software revision, part number (P/N) 81440-xx-241E, -241F, or -241G installed. The “xx” in the P/N is a place-holder for either 02, 03, 12, or 13. FreeFlight Systems Service Information Letter SIL 81440-xx-00-17, dated November 7, 2005, was issued when the manufacturer believed that revision, P/N 81440-xx-241H, would correct the erroneous information displays. However, since the Service Information Letter was issued, it was determined that software revision, P/N 81440-xx-241H, did not correct all the 2101 I/O Approach Plus system malfunctions. An additional software problem which can cause the system to enter Dead Reckoning (DR) mode unintentionally was subsequently discovered. System software revision, P/N 81440-xx-241J, has been approved to correct all the known malfunctions. Updating the system software with software revision, P/N 81440-xx-241J, would be required by the proposed AD.

We estimate that this proposed AD would affect 259 2101 I/O Approach Plus systems installed on aircraft of U.S. registry, and the software upgrade would take approximately 2 work hours per aircraft to accomplish at an average labor rate of $80 per work hour. FreeFlight Systems has stated that they would absorb some of the cost of the upgrade, including cost of the software upgrade and work hours for upgrading the existing software. Required parts would cost approximately $300 per aircraft. Based on these figures, the total cost impact of the proposed AD on U.S. operators would be $72,520, assuming one 2101 I/O Approach Plus system is installed on each aircraft, the manufacturer would provide all $300 in parts at no cost, and the only costs for these parts would be $120 for shipping costs for each unit.

Regulatory Findings

We have determined that this proposed AD would not have federalism implications under Executive Order 13132. Additionally, this proposed AD would 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 the proposed regulation:

1. Is not a “significant regulatory action” under Executive Order 12866;

2. Is not a “significant rule” under the 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 draft economic evaluation of the estimated costs to comply with this proposed AD. See the DMS to examine the draft economic evaluation.

Authority for This Rulemaking

Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, Section 106, describes the authority of the FAA Administrator. Subtitle VII, Aviation Programs, describes in more detail the scope of the Agency's authority.

We are issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III, Section 44701, “General requirements.” Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Safety

The Proposed Amendment

Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration proposes to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) as follows:

PART 39—AIRWORTHINESS DIRECTIVES

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

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