Hatz Biplane Association

I loop mine at 120. In fact, 120 will do fine for just about any vertical maneuver in a Hatz. You might want 125 if you're gonna try a quarter or half roll on the up line. I aileron roll at 100, 110 for a big ol' exaggerated barrel roll with lots of vertical.

It will do a fine loop at 120. 130 gives you a little cushion. I didn't know a stock Stearman could get to 150. It doesn't need that to loop.

Steve

PS - The Stearman hits 150 mph in a dive for a loop. I do not know for sure, but I would guess the Hatz Classic would need to be around 130 mph for the same loop. Anyone have some experience on this?

Michael
9648B

I know - 130 mph was a little wild. Did a left base descending approach for a low fly by - certainly not a cruise speed. As a side note - No vibrations. I am running an Ellison Throttle Body and have only been able to get 2500 RPM - which kind of surprises me. I have a wood 74-58 prop so I am not over proped. Called Ellison but can not get a call back. Very disappointed in their customer support. I have gone through the required set up (twice). The motor runs smooth and strong at 2500 - so I not sure if this (low rpm) is a concern. Still working on the tailwheel problem. I may change to a lighter MATCO tailwheel.

Michael
N 9648B

Congratulations for a very nice job, Michael! Please keep us posted on your flight results. 130 mph is a very high speed for a Hatz! Hope to see you in Brodhead next year!

Kindest regards from overseas

Hans & Sam, H.C. #78, Switzerland

Congratulations Mike. Looks like you did an awesome job. Very inspirational for us still in the building trenches! Oshkosh-bound this summer??

Congratulation!

Hatz's are pretty light on the tail. If the steering springs are too stiff, the tailwheel will just slide before the steering springs stretch enough to allow it to go full swivel.
You don't want it kicking out from full rudder travel, but rather just when you apply brakes in conjunction with full rudder travel. That should stretch the springs just enough to allow it to go full swivel.
3200's are used on some pretty large airplanes that have a lot more weight on the tail than a Hatz, so you might just need to reduce the steering spring stiffness. Personally, I'm not a fan of slack in the steering system.
Mark

Mark please explain more . I have fairly stiff springs and there is very little slack. Do I need weaker springs? and how much slack?

TKS

michael

Michael,
Congratulations, looks great.
If your tailwheel isn't breaking loose, you might need softer springs. It shouldn't unlock just from full rudder travel, but only when the springs stretch past the point of full travel.
Mark