EASA SIB 2020-04: Lithium Batteries used in Emergency Locator Transmitters

What to do

Type certificate holders and design approval holders should evaluate the impact of fire and hot gases from lithium battery failures on aircraft-level safety, especially near stowed safety equipment. Operators carrying affected ELTs or battery packs not part of the approved type design should ensure fire containment to prevent propagation to surrounding materials. EASA also recommends using ELT models approved under RTCA DO-227A for enhanced battery safety. No specific compliance deadlines are stated.

Summary

EASA Safety Information Bulletin 2020-04 is an airworthiness bulletin addressing lithium batteries used in Emergency Locator Transmitters (ELT) from HR Smith (Technical Developments) Ltd and Techtest Ltd. It applies to specific ELT part numbers including 500-12(), 500-27(), 500-32-2Y, 500-32-2Y-S, 500-32-2Y-S-D, and battery packs A01477 and A0696Y, installed on or carried aboard aircraft certified under CS-23, CS-25, CS-27, and CS-29 or equivalent regulations. The bulletin highlights potential fire risks from thermal runaway in these lithium batteries and provides safety recommendations without mandating regulatory action.

What changed

EASA SIB 2020-04 introduces safety information regarding the fire risk associated with lithium batteries in certain ELTs and battery packs. It does not mandate an Airworthiness Directive but recommends assessing fire effects on nearby safety equipment and considering improved battery approvals according to RTCA DO-227A standards. This bulletin supplements existing standards by emphasizing fire impact beyond hot gases in battery failure assessments.

Why it matters

This bulletin is important for aviation professionals because lithium battery thermal runaway can cause fires that may affect critical safety equipment such as flotation devices. Operators, maintenance organizations, and certification teams need to understand these risks to ensure continued airworthiness and safety compliance. The guidance helps prevent potential hazards from battery failures without imposing immediate regulatory burdens.