Stabilized Final Approach

“I will land right-side up no matter what.” Every pilot should say that before each flight. Instead, they tend to take it as a given. It is of supreme importance and a lot of thought must be given on how to make this happen. Close your eyes now and say it yourself. Internalize the sentiment so it lives in your heart.

Term “stabilized approach” is often tossed about in different areas of aviation. For example, each airline has their own unique standard to describe this concept. The idea is pretty simple. A pilot should have all turns complete, be lined up with the landing zone, and be established at the appropriate approach speed by a certain altitude, descending through any low-level wind gradient with the wings level. The approach should be normally into the wind.

This is the goal in the goal-oriented landing. Achieving a safe arrival height is the great enabling principle. After getting home safely, everything else in the pattern is to make this stable final approach goal happen. But by what altitude should a glider pilot be stable? The Soaring Safety Foundation here in the US says 75 ft AGL. The British Gliding Association, on the other hand, says 300 ft AGL. 75 ft is simply too low. We fly a pretty tight pattern here at Harris Hill. A stabilized final approach from at least 200 ft AGL to the surface is the goal.

This, like the other the other landing principles, is transferable to off airport landings. Trees that encircle a farm field may be as tall as 150 ft but they are rarely more than that. A glider pilot must have good habits developed at the home field so that when the day comes and he or she has to put it down in a field, the glider will descend through any wind shadow with the wings level and at 1 g.

Is it the end of the world if a pilot turns final at 150 ft AGL? No. Shoot for 200 ft and if a pilot misses low a little that’s okay. It is a visual maneuver, and no one wants a pilot staring at the altimeter. If, however, a pilot is in the habit of turning final at 150 ft and errs on the low side, that is too low.

In the special case where the approach is a downwind landing for some reason, this must be recognized, and a proper downwind landing technique applied. One legitimate reason for a downwind landing may be having to choose between landing uphill or upwind in an off-airport landing. A pilot has to land uphill if there is a slope.

The other part of this concept is “well selected landing zone.” Every good pilot selects a particular landing spot for every landing. Back up the touchdown spot a little to get a reference point. The stabilized final approach slope is aimed at the reference point.

Here’s a concept that doesn’t get talked about enough–re-selecting the landing zone. If the airport or field is long enough, the pilot can choose a different landing spot if things go awry. This might be appropriate if the pattern is trending low or high or maybe another aircraft is in the way. If the downwind leg is low, fixating on the original touchdown spot can be deadly. Instead, turn base leg earlier and establish a new touchdown spot with a straight final further downfield. If the airspeed is not allowed to build up, the roll out and touch will not use up much distance. If the pattern is blown and and the glider turns final too high, again re-selecting a touchdown spot further down is this better than forcing the aircraft on to the ground at high speed. With our meager 1850 ft runway at Harris Hill these options have limits but they can but helpful to a certain extent and it is easy to choose this option at airfields where there is 4000 ft of runway available. Harris Hill pilots should realize this fixation on the original touchdown spot may be an area of negative training when they later fly off a longer runway.

Speaking of changing your touchdown spot, at Harris Hill we do have the option to change our touchdown spot to a valley landing, to change it to a different location altogether. More on this later but, yes, if a pilot can’t make a good final to a well selected touchdown spot happen at Harris Hill, go to the valley and set up a new final approach to a new, well selected touchdown zone.

One last word about being lined up on final. Yes, at an airport the final approach should be lined up with the runway centerline. In an off-field landing situation, sometimes a small offset may be the way to go. There may be large tree blocking the straight-in approach. A smart pilot may elect to fly around that tree to get down in the field and then make a small straightening turn of maybe 20° heading change once approaching the landing zone. A similar small turn may be needed to align the glider to land uphill versus cross slope.

With proper arrival height, good traffic patterns become possible. A stabilized final approach to a well-chosen landing zone is the ultimate goal of every landing. On every landing look forward and envision how this final approach is shaping up. Modify, modify, modify the traffic pattern to ensure a good final segment.