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Daniel Rose

Its happening way too often… On Labor day weekend I got a text from a friend telling me that yet another Cirrus SR22 had crashed on landing…  This time in Falmouth, Massachusetts. (read about Kreindler’s investigation here). He said, as if it was a foregone conclusion, that it happened during a missed approach like several others have…

A missed approach is the procedure pilots are trained to execute when the landing needs to be aborted, for whatever reason, and the pilot needs to re-try the landing attempt again. (Its also referred to as a “go around” since the plane goes around the landing pattern again to try again.) If you’ve flown on commercial flights enough, you’ve probably experienced one. In commercial aircraft, its usually because the runway is not in sight at the minimum altitude due to the cloud ceilings or visibility being too low and a missed approach/go around has to be made. Also, sometimes a missed approach/go around is necessary because the previous landing aircraft has not yet cleared the runway, so the incoming plane will have to execute a missed approach to avoid the obvious conflict.

When I flew in the Navy onto aircraft carriers, a missed approach/go around happened not infrequently. There the amount of time between landings was 45 seconds, much less than

the typical busy commercial airport landing interval, which is usually between 1 1/2 -2 minutes.  It was much shorter in the Navy because we had to recover aircraft and clear them from the landing area as quickly as possible.  Sometimes it would take longer to disconnect the arresting gear – which is used to “trap” the jet on the carrier – than usual, so a missed approach/go around would have to be executed.

So a missed approach/go around can be necessary for many different reasons; an unstable approach, the runway not being in sight, another aircraft on the runway, or even an animal on the runway.  You never know for what reason you may need to execute a missed approach/go around.

The tactical jets I flew in the Navy were actually easier to conduct a missed approach in than the Cirrus SR22 can be. That’s because, when you apply full power to go missed approach in a tactical

jet, the power is applied symmetrically to the aircraft and is not difficult to control. You just push the throttle full forward, and as the engine smoothly but rapidly spools up power you bring the nose of the aircraft up to a climb attitude and the aircraft starts to climb away… In a propeller plane like the Cirrus SR22 however, when you add full power the airplane tends to cork-screw and turn to the left. If you think of those wind up little wooden rubber band airplanes you probably played with when you were little (or maybe still do) you can begin to understand some of the force that’s created in a propeller plane.

With this significant force to the left, the pilot must try to maintain control of the aircraft by applying right rudder which should counteract the left turning force and allow the aircraft to climb out straight ahead.  The Cirrus SR22 is a very light and powerful (for its weight) aircraft.  As such, a very strong left turning force is created when the plane is at a slow airspeed (high angle of attack) and power is abruptly added, as in the case of a missed approach/go around.  There have been several Cirrus SR22 crashes in the missed approach/go around flight stage that have seriously injured and killed several pilots and passengers.  The landing accident history of the SR22 necessarily calls into question the ability to control the SR22 in this critical stage of flight.  Does the rudder provide the appropriate amount of authority to control the left turning tendency of the aircraft to provide for its safe maneuvering???

The SR22 rudder was initially designed to control the less powerful SR20 model aircraft — which has the same basic airframe as the SR22 but was designed for a much less powerful engine.  The rudder design is critical to the ability to safely control the aircraft in the missed approach/go around flight regime.  Failure to control the aircraft in this critical flight phase begs the question of whether the design is safe.  Notably, the Columbia/Cessna 400 aircraft, which is essentially the same airframe design with the same engine, has not suffered from the same landing crash history as the SR22.  It seems that when Columbia was faced with the same design issue — that is having a more powerful engine in an airframe that was initially designed for a less powerful engine, Columbia went back to the drawing board to redesign the rudder to provide more control in situations such as a missed approach/go around….

I hope that some of these issues will be considered and investigated by the NTSB in this crash, but i’m not optimistic…  this is the type of crash that is too easily “written up” as “pilot error” without digging deeper to see how the man-machine interaction functioned and whether it contributed to the crash…  but that’s for another post…  In the meantime more pilots and passengers have been injured and killed ….

 

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