Why There is an Altitude only Waypoint for the Missed Approach Sequence in the Flight Plan

Every approach sequence in the Garmin Aviation database is carefully programmed for accuracy in order to comply with Federal Aviation Administration (FAA) approach requirements.  However, it is good practice to review the approach waypoint sequence to ensure you have the correct approach loaded properly via the desired transition fixes.  Upon further inspection of the waypoint sequence, you may notice an altitude-only waypoint that is not specifically listed on the approach chart. This waypoint will show on Garmin touch navigators and integrated flight decks for every loaded approach. This waypoint is related to the standard instrument departure procedures and initial turn obstacle clearance.

EXAMPLE

For this example, view the Kansas City Downtown (KMKC) RNAV 21 approach as it appears on the GTN™ GPS navigator below.  In this image the page is scrolled to the bottom following the Missed Approach Point (FISGO).  There is a waypoint entitled “1,157ft” with an altitude constraint assigned to 1,157ft MSL.

Upon inspection of the KMKC RNAV 21 approach chart, you will not find 1,157ft anywhere on the chart. So, what does that relate to? 

The answer to this lies in the Aeronautical Information Manual (AIM) 5-2-9, e.1 which clarifies the requirements for a Standard Instrument Departure.

AIM 5-2-9, e.1:  “Unless specified otherwise, required obstacle clearance for all departures, including diverse, is based on the pilot crossing the departure end of the runway at least 35 feet above the departure end of runway elevation, climbing to 400 feet above the departure end of runway elevation before making the initial turn, and maintaining a minimum climb gradient of 200 feet per nautical mile (FPNM)”

When looking at the MKC chart the field elevation (FE) is 757ft MSL.

***Therefore, 757ft (FE) + 400ft AIM standard instrument departure = 1,157ft MSL.  The exact altitude for the waypoint in question.

This waypoint serves as a quick reference on departure.  Missed Approach operations can be a high workload time for a pilot especially in busy airspace, in Instrument Meteorological Conditions (IMC), and/or flying a non-published missed/Missed Approach Vectors.  This waypoint reference allows the pilot to quickly assess when they can turn to comply with ATC guidance while being at or above the obstacle clearance altitudes to execute the initial turn.