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Aircraft Certification Offices (ACOs)

Contact the appropriate FAA Field Office that serves your geographic area for guidance on aircraft certification related activities.

ACO Branches assist with:

  • Design approval and certificate management
  • Support to Manufacturing Inspection District Office (MIDO) Sections for US production approvals.
  • Type certification & continued operational safety questions
  • Investigating and reporting aircraft accidents, incidents, and service difficulties
  • Designated Engineering Representatives (DER) oversight

Depending on your specific needs, you may want to contact one of the following offices involved in certification and oversight activities:

Engine Certification Office (ECO) Branch
Issues design approvals and oversees continued operational safety of various domestic and foreign aircraft engines, including most large turbofan engines for transport category airplanes.

International Validation Branch
Responsible for all validation activity (inbound and outbound) for aviation products and appliances.

Military Certification Office (MCO) Branch
Supports military commercial derivative aircraft (MCDA) activities on behalf of the U.S. Armed Services.

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