Part 91 operators use of Minimum Descent Altitude as a Decision Altitude

Part 91 operators use of Minimum Descent Altitude (MDA) as a Decision Altitude (DA)

Many navigation systems permit operators to fly non-precision approaches with GPS lateral and vertical navigation guidance. FAA Order 8900.1, Volume 3, Chapter 18, Section 5, paragraph C073 provides guidance on how an MDA may be used as a DA when using vertical navigation (VNAV).

Operators must be authorized with a Letter of Authorization (LOA) C073 in order to use an MDA as a DA with VNAV. This information was originally published in Notice, N 8900.248, dated 12/11/13. The Notice expired 12/12/14 and the information incorporated in the above mentioned 8900.1 guidance. 

Recommended Actions: Operators of aircraft should accomplish the following:

1.View FAA Order 8900.1, Volume 3, Chapter 18, Section 5, paragraph C073 to determine if your aircraft is capable of using MDA as DA.

2.Determine if you are willing to accomplish procedures required in LOA C073.

3.Request LOA C073 from your Principal Operating Inspector at local Flight Standard District Office.

Contact: Questions or comments should be directed to Kel Christianson, Aviation Safety Inspector, AFS-470 at (202) 267-8838.