Definition
An FAA field office responsible for the certification and continued airworthiness oversight of aircraft, aircraft engines, propellers, and related parts within a defined geographic area. ACFOs work under the FAA's Aircraft Certification Service and handle approvals, design changes, and field-level certification activities for manufacturers, modifiers, and operators in their region.
Plain English
A local FAA office that handles the paperwork and approvals for making sure aircraft and aircraft parts meet safety standards. If a manufacturer or modifier needs an FAA sign-off on an aircraft design or change, this is the office that often deals with it.
Context Anchor
Seen in FAA acronym lists, certification paperwork, and discussions about aircraft design approvals or major aircraft changes.
Derivation
The acronym is made from the first letters of Aircraft Certification Field Office. In this context, a “field office” means an FAA office outside headquarters that handles certification work closer to the people or projects involved.
Why Pilots Care
Most line pilots will not contact an ACFO directly, but owners, mechanics, and operators dealing with modifications, STCs, or special airworthiness issues will. Knowing what an ACFO is helps you follow conversations about who approved a particular modification on the aircraft you fly.
Intuition Check
Do not read “field office” as an office located on an airport field. Here it means a local or regional FAA office that handles certification work outside headquarters.
Example Sentence 1
The avionics upgrade required approval from the local ACFO before the aircraft could be returned to service.
Example Sentence 2
An ACFO inspector verified that the installed avionics met all required standards before final approval.