Mastering a tailwheel airplane first requires a keen sense of this "misalignment" and the development of immediate, rapid and controlled rudder response/s. And, the pilot also must develop an ability to input a series of "follow up" rudder inputs to avoid overcontrolling the plane and causing a ground loop in the opposite direction! Some call this process of "wagging the tail" like an excited puppy.
Earning your tailwheel endorsement requires you to demonstrate competency to a CFI, generally on a relatively smooth and level runway, in relatively calm wind conditions.
Landing on a grass strip is supposed to be easier for a new tailwheel pilot, as the touchdown is more "forgiving". I found that to be true to some extent-at least on relatively flat and smooth grass strips.
Here is a landing at Bermudian Valley Airport in East Berlin, PA.
Real world flying often requires landing on bumpy, sloping runways with gusty crosswinds. The new tailwheel pilot will quickly realize there is "more to learn".
Convinced that practicing landings at a Class D airport was not my cup of tea, I decided to move my plane to a grass strip. Specifically, Baublitz Airport 9W8. 100 foot wide turf runways (10/28) with about 2000 feet of usable length. It is shaped like an "M" with a short flat surface at each end followed by a downsloping (2% grade) touchdown area with the low spot in the middle. So touchdown occurs on a downslope, and the final part of the rollout being uphill. (N998SC usually uses less than half the runway length.)
On runway 28, the area adjacent to the touchdown area is higher with a long section of hangars that shade any crosswind from the right. But, once past the hangars a right crosswind will swoop down and challenge your directional control at the most critical part of your post touchdown rollout.
In addition, the turf is good, but it is not a golf green or fairway---it is bumpy enough to make a light plane move around, up/down quite a bit. More like a freshly mowed hay field.
The airport is surrounded by farm fields (corn and/or soybeans) on three sides. The west end of runway 28 adjoins Muddy Creek Forks Rd. with a steep dropoff, telephone poles and wires. On the south side of the runway, there is a 300 foot area with a steep 10 foot drop off on the west portion. Every 200 feet on each side there are 2 foot tall landing lights. Not a place where ground loops occur without penalty except if you are lucky enough to go off into a recently harvested section of farm field on the north side of runway 28.
Here is a video of my first landing...
Before moving my plane, I took instruction from Larry Stone, a CFI (and former airline pilot) at Baublitz in his C172. So, I knew the landing area was a bit bumpy, and concluded that landing on a downhill slope was also "tricky".
Now on my 30th "solo" landing in N998SC, and my 133rd tailwheel landing (around 20 of which were on flat grass runways) during the past year, I was feeling reasonably confident about my crosswind landing technique, but conditions for my first landing at Baublitz were to challenge my personal minimums. Wind was a 45 degree 8 mph crosswind. The crosswind component being around 4 mph, well below my 8 mph personal minimum. Gusts however, were 15-20, so the 7-10 mph crosswind gust component was to test my skills.
The downslope effect was as expected. I needed just a bit extra "forward stick" at touchdown in my wheel landing to keep the front wheels on the ground. The bumpiness however was very distracting and coupled with the gusty crosswind, a lot of control inputs were needed. I did not anticipate the increased crosswind after passing the hangars which pushed my plane to the left.
And, most importantly, I did not remember or sufficiently appreciate the effect of gyroscopic precession when dropping the tail wheel.
Once I had rolled sufficiently far enough to have slowed below stall speed, one reaction to the gust was to get the tail wheel down on the ground. And, since the plane had just been pushed left (right aileron, left rudder for a right crosswind), I pulled the stick back fast while at the same time releasing some of that left rudder and increasing right aileron. Surprise! The plane's nose pointed right much faster than I expected. In addition, instead of the tailwheel on the ground providing almost perfect steering, it was bouncing on the bumpy runway. So I had little help from the tailwheel and with full flaps, engine at idle, and a plane now rolling maybe only 15-20 mph, very little control from air flowing past the rudder. Toe-brakes to the rescue.
During training, you "learn" and "know" many things, but sometimes it takes a bit of experience to make what you "know" a matter of instinct.
First, I knew that "precession" caused the nose to veer left when pushing the stick forward, lifting the tail. (It is one of the four left turning tendencies requiring right rudder durring takeoff.) I also knew that the opposite occured when dropping the tail---"precession" causes the nose to veer right. This day however, my stick back tail down move was not accompanied by any compensating left rudder.
When landing with a left crosswind, this issue is less important as the right turning tendency actually counters the crosswind effect. But when landing with a right crosswind, the right turning tendency from the precession when dropping the tail adds to the weather-vaning force of the crosswind. (Most of my crosswind landing had been with a left crosswind.) Every stick movement requires a coordinated compensating rudder input.
Second, you have to remember adverse yaw when making rapid changes with ailerons. In a gusty situation, a gust from the right may require more right aileron, and the adverse yaw will point the nose to the left.
Third, I knew that full flaps created a risk that the plane could "take off" in a gust. In this case, it did not "take off" but it did get light. It is harder to control a plane when it is bouncing on the runway and is not firmly "planted". I should have taken out the flaps as soon as possible after touchdown.
Fourth, crosswind control requires a steerable tailwheel firmly on the ground with traction, OR enough air flow over the rudder to allow the rudder to control direction. On a bumpy grass strip, the tailwheel may not be firmly on the ground and may not have side force traction. And, if the plane has slowed, with the engine at idle, there may not be enough air flow over the rudder. I should have used a bit of power to generate more airflow to improve rudder control.
Finally---brakes are for holding the plane during runup, BUT ALSO for occasional directional control. Be ready to use them carefully.
Most importantly---anticipate all of the forces on your plane and react instantly and appropriately. Don't let the bumpiness of the runway distract you from flying the plane correctly.
No doubt, some readers will conclude, "He should have done a three point!". The argument and preference of one group of pilots for three point vs wheel landing continues. There is no doubt that a landing with less "energy" makes the consequences of mistakes a bit less severe. However, in a gusty cross wind situtation, on a bumpy grass runway, my preference is to wheel land and to use the rudder for directional control for as long as possible to a point where when the tail is dropped, the plane is almost stopped.
As usual, I am practicing this scenario high gusting right xwind on my Prepar3d Simulator. Including a lot of practice moving the flaps right after touchdown so that I will not be distracted during my real life landings. The bumpy down sloping runway however is something you have to practice in real life.
Here is a video of my third outing a Baublitz.
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