What symbol indicates an MEA/MOCA/MAA change that occurs in the middle of a route (not at a Navaid)?

• A. Circle
• B. Square
• C. Sideways T
• D. Triangle

Answer: (C)

The key idea is that some altitude minima along an IFR route can change at a fix that lies between nav aids. When that happens, the chart marks the point with a sideways T symbol to show a mid-route change in MEA, MOCA, or MAA.

Seeing a sideways T tells you to adjust your altitude to meet the new minimum for the rest of the leg beyond that fix, even though you aren’t at a Navaid. This helps ensure you maintain obstacle clearance and, for MOCA, reliable navigation signal within the required area.

Other shapes on enroute charts denote different features or fixes, not this mid-route altitude change, so they don’t indicate the MEA/MOCA/MAA change point.