Missed Approach

An instrument approach is usually begun with the intent to land. Follow the glideslope, maintain the localizer, watch your airspeed, extending flaps. Ok, that runway ought to be showing up real soon now....instead all of a sudden decision altitude/decision height is upon you, and nothing. No lights or runway. Time to go missed. Let's see...full power, let the tower know, retract flaps and then gear on positive rate of climb. Now where am I going? Darn, where's that stupid chart?!

A missed approach exists for every instrument approach and it allows the pilot to return to the airway structure while remaining clear of obstacles. The procedure is shown on the approach chart in text and graphic form. Since the execution of a missed approach occurs when your cockpit workload is at a maximum, the procedure should be studied and mastered before beginning the approach.

Symbology -

A textual description of the missed approach procedure is found at the top of the chart. Shown here are chart fragments from the VOR or GPS-A at KVNY. It is charted as a dotted line on the plan view of the IAP. Lastly, there will be shorthand symbols in the profile view. This is an easy on to fly. Turning right you climb to 4000, intercept the VNY R-101 and hold at AMTRA (VNY 20.2 DME). Direct entry to the hold.

Technique -

We get in trouble because we tend to expect to land, which of course we almost always do. Better to plan on flying the missed approach every time, then if the runway environment happens to be visible upon reaching minimums, we change our plans and land.

To remember what to do for a particular missed procedure, before reaching the FAF, review the chart. Say the missed instructions out loud and repeat. Write them down, or highlight it on the chart. At the FAF, dial in the missed approach altitude. Add the missed approach holding point to your flightplan in FSNavigator, Squawkbox, FMC or GPS. Note that every missed procedure begins with a climb. If nothing else, remember whether the climb is straight-ahead, to the right, or to the left. Get full power first, gear up and flaps to takeoff setting. then look at your chart after you are established in the climb.

If for any reason you start a missed approach procedure prior to reaching the MAP, unless otherwise cleared by ATC, continue to fly the IAP as specified on the approach plate to the MAP at or above the MDA or DA/DH before beginning a turn. You may climb to the missed approach altitude right away.

If you are flying under radar coverage, then most likely when you advise tower of the miss and switch to approach control, they will vector you almost immediately for another approach or alternate. You probably won't need to fly the procedure, but start it until ATC directs otherwise.

DA/DH vs. MDA -

On a precision approach, upon reaching the DA (altitude above MSL, the term "DA" is replacing the obsolete term DH) or DH (height AGL) a missed approach must be initiated if the visual reference to continue the approach to land has not been established. Your momentum will naturally carry you slightly below the DA as you start the miss. This is ok. But a DA is usually 200 feet AGL, so you don't have much room. Important to start the miss immediately. The missed approach point (MAP) is by definition where you reach DA.

On a non-precision approach, you must not descend below the MDA until the required visual reference to continue the approach to land has been established. This is different than the precision approach and it is the fundamental difference between a DA and an MDA. Can't descend below MDA, but ok to descend below DA provided you have begun the missed approach procedure. This difference stems from the fact that one should level off at the MDA prior to reaching the MAP. For a precision approach, you are on a stabilized descent and there is no leveling off at DA.

Also note that on a non-precision approach most of the time the MAP is at the runway threshold. If you have not established visual contact with the runway environment prior to reaching the MAP, it is unlikely you will be able to land. Why? You will be approximately 500 feet above the runway at that point. Pretty hard to make normal descent to land unless the runway is very, very long. A 500 fpm descent starting at the runway threshold and at 100 knots will take you 6,000 feet until touchdown and 1,000 fpm will take 3,000 feet. Not enough runway left at that point, is there? If timing the approach from the FAF to the MAP, a rule of thumb is that if one minute prior to reaching the MAP, you don't have visual contact, make the decision to miss the approach.