### SENSENICH COMPOSITES, INC.

AREA CODE 813

fireproof-exemption-r4.doc PHONE - 752-3711

FAX - 752-2818 2008 WOOD COURT
PLANT CITY,FL USA

33563

See us on the Web @ www.sensenichprop.com

November 16, 2000

Mr. Jay Pardee Manager, Engine and Propeller Directorate

Federal Aviation Administration 12 New England Executive Park Burlington, MA 01803

Dear Mr. Pardee,

Sensenich Wood Propeller Company, Inc. submits a petition for exemption from Title 14 CFR Part 45.11 b (fire proof mark ings for TCed products) using Sec. 11.81 Petition for Exemption form. This reques ted exemption is for all Sensenich wooden propellers, as detailed in Ty pe Certificate Data Sheet P- 170 and also Type Certificate P00001NY. I have written this letter in a question / answer format, please see below:

Sec. 11.81 Petition for Exemption

(a) Your name and mailing address and, if you wish, other contact information such as a fax number, telephone number, or e-mail address;

Steve Boser Engineering Manager Sensenich Wood Propeller Co., Inc.

2008 Wood Court Plant City, FL 33567 813.752.3711 phone

813.752.2818 fax steveb@sensenichprop.com

(b) The specific secti on or sections of 14 CFR from which you seek an exemption;

Title 14 CFR Part 45.11 b

(c) The extent of relief you seek , and the reason you seek the relief;Sensenich Wood Propeller Co., Inc. requests an exemption from the requirement for fireproof identification on pr opellers. This requested exem ption is for all Sensenich wooden propellers, as detailed in Type Certificate Data S heet P-170 and also Type

Certificate P00001NY. Sensenich manufactures wooden fi xed pitch propellers for small aircraft using conventional methods of cons truction and identificat ion. With a few exceptions, the population of ai rcraft that use fixed pitch w ooden propellers is limited to antique small aircraft. The method of stam ping the required part marking information into the propeller hub was developed to meet the original permanent identification certification requirements of CAM 14.20 prior to the exis tence of §45.11 b. This identification practice has prov en satisfactory in over 68 y ears of Sensenich production, in addition to being the industry standard procedur e of marking identif ication for wooden propellers within the United States and Eur ope. When fixed pitch wooden propellers are typically damaged, the hub portion rema ins intact, providing all the required

information.

The only means of providing fireproof identification requires mounting a metal tag on the propeller hub. Attaching a metal tag to the propeller hub could have detrimental effects on propeller safety and identification. The a ttachment of a metal tag would break the moisture seal and increase the potential for cracking and deterioration and would increase the difficulty in attaining propeller vertical balance. A metal tag could come loose leaving a propeller with no identification. Also, a meta l tag would detract from the authenticity and historical value of antique sm all aircraft, the prim ary users of wooden fixed pitch propellers.

(d) The reasons why gr anting your request would be in the public interest; that is,

how it would benefit t he public as a whole;

The exemption would retain the service proven method of propeller identification while preserving the historical value of antique small aircraft without adversely affecting safety.

(e) The reasons why gr anting the exemption would not adversely affect safety, or how the exemption would provide a level of safe ty at least equal to that provided by the rule from which you seek the exemption;

When wooden propellers are typically damaged, the hub remains intact, thus preserving the stamped required information. This method has proven satisfactory and safe for over 68 years of Sensenich production. A change to add a metal tag could adversely affect propeller safety

fireproof-exemption-r4.docfireproof-exemption-r4.doc (f) A summary we can publish in the Federal Register, stating: (1) The rule from which you seek the ex emption; and (2) A brief description of the nature of the exemption you seek;

Title 14 CFR Part 11 b, states a requirement for fireproof identif ication on propellers. Sensenich requests an exempt ion from this requireme nt for wooden fixed pitch propellers for the following reasons:

1. Original intent was for identification means which was not likely to be defaced or removed during normal service or destroyed in an accident. The current method of directly stamping into the wooden hub has pr oven satisfactory for over 68 years of Sensenich production. Typical damage to a wooden fixed pitch propeller leaves the hub intact, thus preserving required information.

2. Incorporation of metal i dentification tag would affect environmental resistance (due to screws breaking the moisture seal) and also make vertical balancing of the propeller more difficult. .

3. A metal tag could come loose leavi ng a propeller with no identification.

4. A metal identification tag would detract from the authenticity and hist orical value of antique small aircraft, the primary us ers of wooden fixed pitch propellers.

This requested exemption is for all Senseni ch wooden propellers, as detailed in Type

Certificate Data Sheet P-170 and al so Type Certificate P00001NY.

(g) Any additio nal information, views or arguments available to support your request;

and

None.

(h) If you want to exer cise the privileges of your exem ption outside the United States, the reason why you need to do so.

No.

Thank you for your attention to this ma tter. Please contact me with any questions.

Sincerely,

Steve Boser Engineering Manager Fi reproof-exemption-r4.doc