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86-21-08: Battery Tray

FAA order 86-21-08 is an airworthiness directive in force since October 24, 1986. The FAA's subject line: Battery Tray. It names Daher (Socata) TB 10, Daher (Socata) TB-20: about 253 aircraft on the U.S. register today across them, though an order usually covers particular versions or serial numbers rather than every one. System: electrical power.

What it applies to as the FAA lists it

Kind of product
Aircraft
Makes
SOCATA
Models
TB 10, TB 20
On this site
Daher (Socata) TB 10 53 registered
Daher (Socata) TB-20 200 registered

Dates and paperwork

In force since
October 24, 1986
Docket
Unknown
Status
Current
The FAA's document
Read the order on the FAA's site

The order itself the regulatory text, as published

Show the full text (1,699 characters)
86-21-08 SOCATA: Amendment 39-5444. Applies to Models TB10 and TB20 (Serial Numbers 1 through 342, 344 through 381, 383 through 413, 415 through 422, 424, 430, 431, 433, and 439 through 441) airplanes certificated in any category. Compliance: Required within 50 hours time-in-service or 60 days, whichever occurs first, from the effective date of this AD, unless already accomplished. To prevent possible structural damage and loss of airframe integrity, accomplish the following: (a) Visually inspect the fuselage area under the battery tray for damage caused by battery electrolyte leaks. (1) If damage exists, before further flight, repair the damage or replace the damaged component(s) in accordance with Advisory Circular No. 43.13-1A and applicable manufacturer's maintenance information and modify the battery tray as specified in paragraph (a) (2) below. (2) If damage does not exist, modify the battery tray in accordance with the instructions in the "DESCRIPTION" Section1 of SOCATA Service Letter No. 18 dated February 1985. (b) Airplanes may be flown in accordance with FAR 21.197 to a location where this AD may be accomplished. (c) An equivalent means of compliance with this AD may be used if approved by the Manager, Aircraft Certification Staff, AEU-100, Europe, Africa, and Middle East Office, FAA, c/o American Embassy, 1000 Brussels, Belgium. All persons affected by this AD may obtain copies of the documents referred to herein upon request to SOCATA Groupe Aerospatiale, B.P. 38, 65001 Tarbes, France, or FAA, Office of the Regional Counsel, Room 1558, 601 East 12th Street, Kansas City, Missouri 64106. This amendment becomes effective on October 24, 1986.

Related safety bulletins advice on the same designs, not orders

2018-11-21SW-18-31 · NAVIGATION, ATTITUDE, AND DIRECTION DATA SYSTEM
2003-11-06CE-04-14 ·
2003-10-23CE-04-09 ·
2003-10-22CE-04-07 ·
2003-10-22CE-04-08 ·

Source: FAA Dynamic Regulatory System, airworthiness directives. The FAA's document is the authority; the register counts are this site's, from the FAA register of November 6, 2026. Connections as data: /graph/directive/86-21-08.json · aircraft systems.