Re: "Darting" to Left on Slow Speed Taxi

David J. Gall

So you’re taxiing downwind at idle at 15 kts. with a tailwind gusting 18-26 kts. from 20 degrees to the right off your tail. Basically, your vertical stabilizer/rudder is at zero airspeed gusting to -10 kts. airspeed. Any change of wind direction to be more from the left off your tail is going to be changing the roll moment imparted by the wing dihedral as much as the yaw moment imparted by the vertical stab/rudder. I think almost any taildragger would behave similarly, but the Quickie main gear is known to be a little more responsive to roll coupling than other planes. Did it do anything similar on the taxi back to the hangar when you had a headwind? If not, I’d diagnose it as “Corbin flies his Quickie when mere mortals cower in the hangar.”


On Dec 22, 2020, at 1:33 PM, Corbin via <c_geiser@...> wrote:

[Edited Message Follows]

Well, I thought today would be the first day I flew with the new Lightspeed ignition.  My plan was to do a couple high speed taxi tests and, if all was well, then depart for a test flight.  However, when simply taxiing down to the runup area it "darted" left on me twice.  I don't think it was because my feet aren't awake from not flying.  It just seemed to randomly "dart" left.  

The pedals and brakes feel normal and there is no play in the rudder cables.  Could it be the left tire/caliper is grabbing but then releasing.  I don't know where to begin troubleshooting.

I had a camera recording but not with the tailwheel in view.  Here is the video in case you want to see the "dart" and have any ideas for me to look into tomorrow.  I included the startup just for fun.  Skip to 1:15 and 2:15 for the two darts before I decided to head back to the hangar.

Could it simply be wind gusts....they started picking up around that time.  My heading on taxi was 360 and winds were 160 18-26kts....




Join { to automatically receive all group messages.