ETSO-C49b

• ED Decision 2003/10/RM found in: CS-ETSO Amdt 17 - European Technical Standard Orders (Oct 2026)

#### ETSO-C49b *ED Decision 2003/10/RM* ##### **Electric Tachometer: Magnetic Drag (Indicator and Generator)** **1 Applicability** This ETSO gives the requirements which electric tachometers: magnetic drag (indicator and generator) that are manufactured on or after the date of this ETSO must meet in order to be identified with the applicable ETSO marking. **2 Procedures** 2.1 General Applicable procedures are detailed in CS-ETSO [Subpart A](#_DxCrossRefBm920220672). 2.2 Specific None. **3 Technical Conditions** 3.1 Basic 3.1.1 Minimum Performance Standard Standards set forth in the SAE Aerospace Standard (AS) document: AS 404B dated February 1, 1959, and reconfirmed May 1991, as amended and supplemented by this ETSO: Exceptions. (i) The following specifically numbered parts in AS-404B do not concern minimum performance and therefore are not essential to compliance with this paragraph: Parts 3.1, 3.1.1, 3.1.2, 3.2, 3.2(a)(b)(c)(d)(e)(f), 4.1.3.1, 4.1.3.2, 4.1.3.3, 4.1.3.4, and 4.1.3.5. (ii) In lieu of part 7 in AS-404B, it is a requirement that tachometers covered by this paragraph be capable of successfully passing the tests in parts 7.1 through 7.8. 3.1.2 Environmental Standard As prescribed in AS 404B. 3.1.3 Computer Software See CS-ETSO Subpart A paragraph 2.2 3.2 Specific None. **4 Marking** 4.1 General Marking is detailed in CS-ETSO Subpart A paragraph 1.2; in addition, range and rating shall be shown. 4.2 Specific None. **5 Availability of Referenced Document** See CS-ETSO Subpart A paragraph 3.