September 0 4, 2013 U.S. Department of Transportation Docket Operations West Building, Room W12 - 140 1200 New Jersey

Avenue, S.E. Washington, D.C. 20590 Subject: Petition for Exemption,

Delta Engineering for Project ODA - 22 33 - 0 3 Title 14 CFR § 2 3 . 1359 ( c ) , amendment 2 3 - 49 Subject: Request for immediate exemption from Title 14 CFR § 2 3 . 1359 ( c ) for the wire and cable located within certain metal electronic articles. 

### Introduction: Ina ccordance with Title 14 CFR Part 11, Delta Engineering is petitioning for an immediate exemption from Title 14 CFR § 23 . 1359 ( c ) for the wire and cable located within certain metal electronic article s , where the electronic article is located in a non - fire zone. Delta Engineering’s STC project , ODA - 22 33 - 03 is for the installation of various electronic articles in the fuselage, in the cabin, in the Electronics Rack, and under the floor, of a Beech Kingair B300 aircraft. M any of the electronic articles are commercial off the shelf articles . Title 14 CFR § 2 3 . 1359 ( c ) amendment 2 3 - 49 states, “ Insulation on electrical wire and electrical cable must be self - extinguishing when tested at an angle of 60 degrees in accordance with the applicable portions of Appendix F of this part, or other approved equivalent methods. The av erage burn length must not exceed 3 inches (76 mm) and the average flame time after removal of the flame source must not exceed 30 seconds. Drippings from the test specimen must not continue to flame for more than an average of 3 seconds after falling. ” This regulation does not provide relief if the wire or cable is located within a non - flammable metal case, electronic article. Based upon requirements of Title 14 CFR § 2 3 . 1359 (c ) even the electrical wire and cable located within a metal case electroni c article must be tested per Appendix F. 

### Supporting data for the requested exemption : As provided in FAA Advisory Circular 21 - 16G the FAA finds the criteria in RTCA DO - 160G sufficient for compliance with Title 14 CFR Part 25. W ithin RTCA DO - 160G, Section 26.3.3 it is establishes two conditions wherein flammability

testing is NOT required. A s worded the wire and cable within an electronic article that meets those conditions would not require flammability testing, even though this may be contrary

to the wording provided in Title 14 CFR § 2 3 . 1359 ( c ) amendment 2 3 - 49 .When shielded wire assembly , or coaxial cable is tested for compliance the test subjects the flame to the outer surface of the shielded wire or coax. When the shielded wire assembly or coaxial cable assembl y i s found compliant additional testing is not conducted on each wire internal to the shielded assembl y, or when the coaxial cable is found compliant the center insulator and conductor are not separately tested. L ikewise should be wire and cable within an assembly that would prevent an external flame from propagating internal to the electronic article, or an internal flame f rom being able to propagate externall y. 

### Proposed Requirements for Equivalent level of safety: To ensure an equivalent level of safety as provided by Title 14 CFR 2 3 . 1359 ( c ) amendment 2 3 - 49 , Delta Engineering is proposing the following: Wire and cabl e located internal to the e lectronic articles/ metal cased articles located in non - fire zone s if any of the following conditions are met: 1) The enclosure is constructed of metal (metal finish that is non - flammable), on all sides, and has no vent holes. 2) The enclosure is constructed of metal (metal finish that is non - flammable) on five sides and one side is constructed of a material that has met 12 second vertical test, and has no vent holes 3) The enclosure is constructed of metal (metal finish that is non - f lammable) on all sides and has vent holes, provided test and/or anal ys is substantiates an external fire event cannot propagate to the inside of the metal case and subject any of the wire or cable to the flame. The test and/or anal ys is substantiates an internal fire event cannot propa gate out of the metal case and subject any external item to a fire that would be located within three inches (3”) of the electronic article . 4) The enclosure is constructed of m etal (metal finish that is non - f lammable) on five si des with vent holes and one side is constructed of a material that has met 12 second vertical test, provided test and/or anal ys is substantiates an external fire event cannot prop agate to the inside of the metal case and subject any of the wire or cable to the flame. The test and/or analysis substantiates an internal fire event cannot propagate out of the metal case and subject any external item to a fire that would be located within three inches (3”) of the electronic article.

### Public Interest: Granting this request for exemption would benefit the public by not requiring additional articles to be purchased to support flammability

testing of the wire and cable that is used on the internal of the electronic article s . Sincerel y, John A. Moritz Delta Engineering 13 DRBA Way New Castle County

Airport New Castle, Delaware 1 9720 Phone (302) 325 - 9337 E Mail jamoritz@delta - engineering.com