Published date: 17 September 2021


This AC describes an acceptable means of compliance with standards for the approval and use of both portable and installed Electronic Flight Bag (EFB) devices in aircraft.

Related rules

This AC relates specifically to parts in rules 121, 125 and 135 listed in Section 4 on page 5 of this document.

Change notice

This is the first revision of AC91-20. It completely updates section 7, Background, and section 8, Evaluation of Portable Hardware Components. It also updates section 9.2, Type B Software Applications, and updates section 12.13, Training. Lastly, it renumbers and deletes duplicate sections, with the effect that section 10 in the first version is now section 8, section 11 has been largely deleted and what was section 13 in the previous version is now section 12.