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###### Department of Transportation

###### Federal Aviation Administration 

          - [Docket No. FAA-2006-23658] 

# AGENCY:

Federal Aviation Administration (DOT). 

# ACTION:

Notice of availability and request for public comment. 

# SUMMARY:

                            This notice announces the availability of, and requests comments on proposed Advisory Circular (AC) 20-HIRF, The Certification of Aircraft Electrical and Electronic Systems for Operation in the High Intensity Radiated Field (HIRF) Environment. This proposed AC provides information and guidance concerning an acceptable means, but not the only means, of showing compliance with the High Intensity Radiated Field (HIRF) Notice of Proposed Rulemaking (NPRM) published in the                             **Federal Register**                             on February 1, 2006, regarding the operation of electrical and electronic systems on an aircraft when the aircraft is exposed to an external HIRF environment.                         

# DATES:

Comments must be received on or before May 2, 2006. 

# ADDRESSES:

You may send comments identified by Docket Number FAA-2006-23658 using any of the following methods: 

                            1.                             *DOT Docket Web site:*                             Go to                             *http://dms.dot.gov*                             and follow the instructions for sending your comments electronically;                         

                            2.                             *Mail:*                             Docket Management Facility; U.S. Department of Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401, Washington, DC 20590-001;                         

                            3.                             *Fax:*                             1-202-493-2251; or                         

                            4.                             *Hand Delivery:*                             Room PL-401 on the plaza level of the Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.                         

# FOR FURTHER INFORMATION CONTACT:

                            Richard E. Jennings, Aircraft Certification Service, Aircraft Engineering Division, AIR-130, Federal Aviation Administration, c/o Atlanta Aircraft Certification Office, 1895 Phoenix Blvd., Suite 450, Atlanta, GA 30349. Telephone (770) 703-6090. Or, via e-mail at:                             *Richard.Jennings@faa.gov*.                         

# SUPPLEMENTARY INFORMATION:

## Comments Invited 

                        Interested persons are invited to comment on the proposed AC listed in this notice by submitting such written data, views, or arguments as they desire to the above specified address. Comments received on the proposed AC may be examined, before and after the comment closing date, in Room PL-401 on the plaza level of the Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9 a.m. and 5 p.m. Monday through Friday, except Federal holidays, or on the DOT DMS Web site                         *http://dms.dot.gov*                         at any time. All communications received on or before the closing date will be considered by the Manager of the Aircraft Engineering Division, Aircraft Certification Service, before issuing the final Advisory Circular.                     

## Background 

The external HIRF environment exists because of the transmission of electromagnetic radio frequency (RF) energy from radar, radio, television, and other ground-based, shipborne, or airborne RF transmitters. Because of the vulnerability of aircraft electrical and electronic systems to interference from the electromagnetic RF energy generated by these transmitters, the FAA proposes to add airworthiness standards to protect these systems from this external HIRF environment. This proposed AC provides designers, manufacturers, and installers, with general information and acceptable means to show compliance with the FAA's proposed HIRF airworthiness regulations. 

## How To Obtain Copies 

                        You may get a copy of proposed AC 20-HIRF from the Internet at:                         *http://www.faa.gov/​aircraft/​draft_​docs/​*. See section entitled                         **FOR FURTHER INFORMATION CONTACT**                         for the complete address if requesting a copy by mail.                     

Issued in Washington, DC, on January 25, 2006. 

Susan J. M. Cabler, 

Acting Manager, Aircraft Engineering Division, Aircraft Certification Service. 

[FR Doc. 06-897 Filed 1-31-06; 8:45 am] 

BILLING CODE 4910-13-P