IRImplementing rule
ETSO-C27a
1 Applicability
This ETSO provides the requirements which twin seaplanes floats that are designed and 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
The applicable procedures are detailed in CS-ETSO, Subpart A.
- 2.2 Specific
None.
3 Technical conditions
3.1 Basic
3.1.1 Minimum Performance Standard
The applicable standards are those provided in Aerospace Industries of America, Inc., National Aerospace Standard (NAS) 807, Revision 2, Twin Seaplane Floats, dated 30 June 2017.
3.1.2 Environmental Standard
See CS-ETSO, Subpart A, paragraph 2.1.
3.1.3 Software
See CS-ETSO, Subpart A, paragraph 2.2.
3.1.4 Airborne Electronic Hardware
See CS-ETSO, Subpart A, paragraph 2.3.
3.2 Specific
3.2.1 Functionality
The standards of this ETSO apply to twin seaplane floats that are suitable for use on aeroplanes.
3.2.2 Failure Condition Classification
A failure condition classification is not required.
3.2.3 Functional Qualification
The materials and workmanship must conform to the requirements specified in Section 3 of NAS 807, Revision 2. The functional performance must be demonstrated under the test conditions specified in Section 4 of NAS 807, Revision 2. The applicant must define the design parameters to which the article is qualified (e.g. maximum aeroplane weight, Vso, etc.).
TWIN SEAPLANE FLOATS
ED Decision 2020/011/R
- 4 Marking
4.1 General See CS-ETSO, Subpart A, paragraph 1.2. 4.2 Specific None.
5 Availability of Referenced Documents
See CS-ETSO, Subpart A, paragraph 3. [Amdt ETSO/16]
IR · ETSO-C27a — CS-ETSO · CS-ETSO Easy Access Rules · EAR revision 14 Aug 2026