Timing-Based Approaches

Timing-based approaches are non-precision instrument approaches in which the Missed Approach Point (MAPt) is identified by elapsed time, rather than by a navigation aid (like DME or GPS). These approaches require the pilot to start a timer when crossing the Final Approach Fix (FAF) and use aircraft groundspeed to determine when to begin the missed approach if the runway environment is not visible.
This method is primarily used in traditional NDB, VOR, and LOC approaches without distance-measuring equipment.

• Provide a way to safely complete non-precision approaches where more precise fixes (e.g. DME, GNSS waypoints) are not available
• Allow calculation of the Missed Approach Point based on time and speed
• Serve as a backup method for aircraft without advanced avionics

• Cross the FAF (Final Approach Fix) at or above the final approach altitude
• Start a stopwatch or timer immediately
• Maintain the published approach speed (groundspeed)
• Time to MAPt is found in a table on the approach chart
• If required visual reference is not established at that time, initiate the missed approach procedure

You may see a note like:
"MAPt at 3:45 from FAF at 90 KT"

• ❌ Sensitive to wind error — incorrect groundspeed = incorrect MAPt
• ❌ More workload-intensive than GPS or DME-based approaches
• ❌ Not permitted in high workload or low-visibility environments unless trained
• ✅ Still valid for IFR checkrides and legacy procedures

• “Crossed FAF, timing started.”
• “Approach stable, 1 minute to MAPt.”
• “No visual contact at MAPt, missed approach initiated.”

• ✅ Know your category-based approach speed and check the timing chart before descent
• ✅ Use a digital timer or cockpit stopwatch—avoid relying on mental math
• ✅ Practice with LearnATC’s classic NDB/VOR modules to develop timing proficiency
• ✅ Monitor descent rate and speed carefully to avoid early or late arrival at MAPt