U.S. Department of Transportation Federal Aviation Administration


### MAR 2 

## 82016
FEDERAL EXPRESS
Mr. Glenn Baxter Manager, C Series Airworthiness Bombardier Aerospace 400 Cote-Vertu Road West Dorval, Quebec, H4S 1 Y9 CANADA
Dear Mr. Baxter: Transport Airplane Directorate 1601 Lind Avenue, S.W. Renton ,Washington 98057-3356

We have received your petition letter dated February 18,2016, in which Bombardier requested a time-limited exemption from the requirements of§ 25.981(a)(3) ofTitle 14, Code ofFederal Regulations (14 CFR). The exemption, ifgranted, would allowBombardier 3 years after type validation to incorporate necessary design changes to the fuel boost pump on Model BD-500-1A10 (CS100) and Model BD-500-1A11 (CS300) airplanes to fully comply with 14 CFR 25.981(a)(3). Bombardier's request was posted to the Department of Transportation's Federal Docket Management System (at Regulations.gov) on February 24,2016, and was assigned Docket No. FAA-2016-4198.
The petition states that full compliance with§ 25.981(a)(3) will require the introduction ofa ground fault interrupter (GFI) or a fast-acting arc fault circuitprotection device. Itfurther states that Bombardier is assessing and evaluating potential design solutions to incorporate either a GFI or a fast-acting arc fault circuitprotection.device into the AC boost pump external electrical wiring in order to fully comply with§ 25.981(a)(3).
We have reviewed your petition, and have determined that more information is needed before we can process it. In the petition, it is not clearhow Bombardierplans to fully comply with the requirements of§ 25.981(a)(3) as it applies to the fuel pump installation; and it is also unclear why Bombardier needs relieffrom§ 25.981(a)(3) for a 3-yeartime period after FAA type validation. Therefore, Bombardier'spetition should be supplemented to provide more substantial assurance that they will design and develop a certifiable GFI or fast-acting arc fault circuitprotection in accordance withthe requirements defined in Issue Paper P-32. Additionally, in orderto substantiate the necessity ofBombardier's 3-year requirement to fully comply with§ 25.981(a)(3),the FAA requires a detailed schedule that includes completion dates for the design and certification ofthe GFI or fast-acting arc fault circuitprotection. Furthermore, Bombardier must also provide a schedule for production implementation and retrofit ofthe existing fleet.Please provide the requested information within 30 days ofthe date ofthis letter, by submitting itto the established docket (FAA-2016-4198). Ifthe additional information is not submitted within that timeframe, we will cease work on the project with no further correspondence to you. Please note that our work will only resume when we receive your additional information, addressed to the established docket. 2

Bombardierrequested that the action on this petition not be delayed by publication and commentprocedures. However, Bombardier's requested reliefis not identical to exemptions granted previously and would set a precedent. Therefore, once we have the additional information from Bombardierthat we need, we will publish a summary ofyour petition in the Federal Register, for a 20-day commentperiod, in accordance with the requirements of§ 11.89. Please note that according to§ 11.63(d), petitioners must submit an exemption request 120 days before the exemption is needed to take effect. However, you will be advised ofthe agency's decision on your petition as soon as possible after the commentperiod closes.
Ifyou have any questions or concerns regarding your petition orthe petitionprocess, please contact Margaret Langsted at (425) 227-2677, orby e-mail at Margaret.Langsted@faa.gov. Sincerely,

# Jfl?-VJon Regimbal Acting Manager, Propulsion/Mechanical Systems Branch Transport Standards Staff Transport Airplane Directorate Aircraft Certification Service