Hatz Biplane Association

Hi Hatzers,

As a preparation for FAA acceptance we have to verify all control surface movements. We found out, that our elevator up movement is restricted to 24° instead to 30° as shown on Makelan plans. There might be a fault eigther in the lenght of control rods (which are set by adjustment at shortest possible lengths), which we have to verify or the lateral position of the control column might be misplaced.
Anyway, before removing the control rods and make any mechanical modifications, we wanted to post this matter in order to learn if that 30° up deflection is really necessary!
We hope to hear from both the Classic and CB-1 flying comminity about their flying experience. Our concern is that we have enough movement to fully stall the plane on 3-point landing (our Hatz is standing steep at 13.5°on ground).
One matter which might help with less movement is our design change to the tailplane planform, as the mean chord of the elevator is longer than on the drawings due to our elliptical elevator shape. However, this is just an assumption...

Your input from flight experience would be most welcome!

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

Hans,

I will measure mine this weekend, until then I will venture a guess that you will be fine unless you have a nose heavy airplane. Where did your CG work out to?

Steve

I measured NX1279, I've got 30 deg up and 15 deg down.

Thank you Mark for your mesurements!
We could adjust the rod between the pilot's stick and the yoke a little bit and reached now + 27° and -15°! Might that be ok? Does anyone used full aft stick on touch down?

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

Even with longer main gear and a small tailwheel, I can still touchdown tailwheel first with full aft stick, so for me 30 degrees is more than enough. With 27 degrees, the plane will fly safely. If during flight test you find that you prefer a little more travel, adjustments can be made, after all that's the whole point of flight testing.
Mark

Mine is 27 degrees also. Have never felt I need more.

Steve

Thank you Mark and Steve, your input is most appreciated! We are feeling good with this set up.
Kind regards
Hans & Sam, H.C.#78, Switzerland

As a preparation for FAA acceptance we have to verify all control surface movements.

FAA? In Switzerland?

Hi Al,

Over here it is called BAZL (Bundesamt fuer Zivilluftfahrt), but in terms that you guys know what we are talking about I simply wrote FAA....
Our BAZL require much more paperwork than your FAA. That's the reason, we still haven't made the first flight!
Kind regards

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