Wheel landings

 

There are two common techniques used to land tailwheel aircraft:  three-point and wheel landings.

 

Three-point refers to the landing attitude – typically around 5 degrees nose up – which allows all three tires of the tailwheel aircraft to contact the runway at the same time.

 

Wheel landing refers to a near-level (or slightly tail low) landing attitude, where the two main tires touch first, and after a while, the tailwheel is gently lowered to the ground.

 

Almost all tailwheel instructors, including myself, start students with the three-point landings, and only after they have developed some proficiency with the rudder, is the wheel landing introduced.

 

Many pilots of light tailwheel aircraft never master the wheel landing, and that’s ok.  Other pilots prefer wheel landings all the time.  Whatever works for you, in that particular airframe, in that particular situation.

 

The way I teach tailwheel landings is for the student, just as he would in a nosewheel aircraft, to establish himself on the runway centerline – let’s forget about crosswinds for now, so no crab required on final.  I like to turn the VASI/PAPI lights on, so that the student can clearly see if he is too high (all white lights) or too low (all red lights).  Too high, push the nose down.  Too low, pull the nose up.

 

Once the student is established on the runway centerline and correct glidepath, then the desired airspeed is attained with the use of power.  Too slow, add power (and typically push the nose down).  Too fast, reduce power (and pull the nose up).  If power reduction won’t cure excessive airspeed, a forward slip is a good idea.  I try to use the same amount of flaps every time, for the sake of consistency in the flare.  The amount of flaps I like to use is the amount of flaps specified for takeoff – often zero degrees, to reduce pilot workload during a touch & go landing.

 

However you get there, it’s important for the student to precisely maintain the desired airspeed until passing over the runway threshold, and then the power is reduced to idle, and the student can now entirely focus on flaring the aircraft to the three-point attitude and establishing it at a height of ideally less than one foot above the ground.  With the power off, airspeed will be decreasing and the pilot does his very best to try to stop the aircraft from touching down with progressive back elevator.  Eventually the aircraft runs out of speed and lift, and settles down on the runway.

 

Hopefully the pilot has kept the aircraft perfectly aligned with the direction of travel.  Any crab will now launch him to the side of the runway as discussed before.

 

Once the aircraft sits down on the runway, the stick is steadily pulled all the way back, to put weight on the tailwheel to improve directional control, and to get rid of any porpoising in pitch.

 

At this point, the student can now totally concentrate on using his feet to stay straight – that’s the only thing he has to do at this point.  The power is off, the stick is all the way back, and the ground speed should be decreasing during the rollout.  As required, the student will perform the Three Step as described before to control the aircraft directionally.  Eventually the speed will decrease during the rollout to a taxi speed.  The slower the aircraft is moving, the easier it will be for the student to control it.

 

Below 20 mph, you’re really taxiing.   A light tailwheel aircraft might touch down around 50 mph, but it won’t have much weight on the tires at that speed – the wings are still developing significant lift, and if you try to use the brakes, all you will do is flat-spot the tires.  Between 40 mph and 20 mph is what I call the “expensive speed”.  You won’t kill yourself  - or likely even get hurt badly – if something goes horribly wrong, but you can sure spend a lot of money if you lose control of the aircraft between 40 mph and 20 mph, because you can’t fly, but you are careening down the runway with a lot of speed on.

 

Keep in mind that aircraft – even nosewheel aircraft – are lousy ground vehicles.  They are about as graceful as an enormous pregnant duck, and the faster they go, the crappier they are.  Tailwheel aircraft are horrible ground vehicles, and the faster you go on the ground, the worse they get.

 

Anways, first the student masters the three point landing, which allows him to concentrate solely on keeping the aircraft straight with his feet after touchdown, with the stick all the way back.  Once the student masters the three point landing, they can work on the wheel landing.

 

Wheel landings can be awfully frustrating.  The reason why is that if you don’t get a greaser touchdown, after the mains touch down, the center of mass behind the mains has momentum and it pulls the tail down.  This increases the angle of attack of the wing, and hence lift, shooting the aircraft up and converting what little airspeed it had into height with near-zero airspeed (and lift).  A hard second touchdown usually follows, and this porpoising can get worse with each successive bounce.  As always, when something goes wrong with a tailwheel landing, apply FULL POWER, stabilize and accelerate with a couple feet of height, get some airspeed and get up and get the hell out of Dodge.  Calm the nerves, go around the pattern, and get set up again.

 

The secret to a good wheel landing is to sideslip, as if there was a crosswind – even if there is no crosswind!  This allows one main to touch first, and if you don’t get a greaser touchdown, the other main comes down – not just the tailwheel – so the angle of attack (and hence lift) doesn’t increase, shooting you back up into the sky.  A little forward stick to decrease the AOA and stick the mains on the ground and you’re rolling down the runway, now with two chores – stay straight with your feet, and control pitch with the stick via the elevator.

 

This is why I recommend teaching wheel landings after three point landings, because the touchdown is trickier and the workload is higher during the rollout.

 

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acboyd@gmail.com  Sept 2011