Taildragger tail dragging

[Hank Jarrett]

Re: Taildragger tail dragging

Same way we did it. If the bubble isn't level both ways, you just get another level.

Hank

[astjp2]

Re: Taildragger tail dragging

Proper levelling is necesssary as well...I expect everyone's spirit level across the stabilser spars is calibrated to an International Standard, is it not?

Rob

No such thing, you just turn it around. I work on $1,500,000 mills and we just turn the "Starret" level around when we level after a move. Tim

[Hank Jarrett]

Re: Taildragger tail dragging

Are you sure the "Taylorcraft brick" didn't fall out of the tail?
Hank ;-)

[1938BF50]

Re: Taildragger tail dragging

I was able to get in (3) take-offs last night after making the above mentioned washout adjustments. The first takeoff was cautious with full concentration on the narrow runway. The next two takeoffs were made on the grass with the tail popping up nicely after a short run. I am shocked that a 1/2"-5/8" change in washout would have this much(apparently) effect on the tail lifting. It makes no sense from a logic perspective. I am really happy that I can now(easily) lift the tail on takeoff.

Re: Taildragger tail dragging

Have you guys checked your elevator travel?

Also any chance that the stabilzer is not in the proper plane? ie there has been damage such that the stabizer mounts no longer represent the level positon of the aircraft?

Dave

[1938BF50]

Re: Taildragger tail dragging

DC,

I expect the same. Anxious to get up tonite. I thought it interesting that both adjusters are completely out of travel(adjusted out) to just get to the 1 5/16" wash.

[flyguy]

Re: Taildragger tail dragging

Rather surprised that it wasn't tail heavy. This is getting interesting. As to the wash-in/wash-out, I experimented with my 12D, both wings in, both wings out, and the fairly unsymmetrical adjustment that I have now and I didn't notice ANY affect on the pitch behavior at take off.

Now I suspect it will be still do the same thing and roll left in level flight.

DC

[cvavon]

Re: Taildragger tail dragging

Mike your tail wheel weight is 10 # lighter then my plane and even when it was a a65 the tail came up easy see what the wing adj did then look at the thrust line it should be 0 to check level the plane and put a straight edge on the prop hub with a level if the level is centered it's at 0 deg thrust line if not shim motor mount to 0.

[1938BF50]

Re: Taildragger tail dragging

I finally got a chance to spend some time working on the plane this last weekend. Here is what I found. Wash-in on the LH wing was 1 7/8" and the RH wing was 1 5/8". Factory setting is 1 5/16". I adjusted both to 1 5/16". Weight on the tailwheel with the plane leveled was 59#. I hope to get a chance to fly tonite to see if the rigging change has any effect on the tail "heavy" takeoff issue that started this thread.

[cvavon]

Re: Taildragger tail dragging

When we put c85 on my plane i had a similar thing happen not as bad as you are we had the wrong washers on the engine mount bolts and that let the engine sag so the thrust line was off put on right part an the problem went away. also my tail wheel is 69 lbs and light weight is 777 lbs and like Rob said the pre war are fun.

[flyguy]

Re: Taildragger tail dragging

Get a digital bathroom scale and weigh the tail just with it sitting on the ground. I WOULD NOT fly the plane again until I have done that. You are not looking for one ounce accuracy here.

The simplest answer is not always the correct one, but that is the way to bet, and it sure sounds like it is way tail heavy.

Just for reference my 12D-85's tail weight is around 90 lbs with the tail on the ground, and it flies just fine, even with just a few gallons in the front tank.
DC

[1938BF50]

Re: Taildragger tail dragging

Tom, Rob,

Understood. I think that I am looking for something fairly obvious here. The fact that I can use really stout forward yoke pressure to try and pop the tail up and still takeoff gear first is really intriguing me at this point. I have to instantly nose down to maintain airspeed.

[Robert Lees]

Re: Taildragger tail dragging

Mike, if you do check the weight for real make sure to measure the actual arm for the weights with the airplane levelled up.

Too true...drop lines from the leading edge, the main gear, and the tailwheel to the hangar floor and chalk where they sit, and then measure accurately. Don't use the book figures...these dimensions have to be for YOUR aeroplane.

Rob

[Robert Lees]

Re: Taildragger tail dragging

...and all my weighings were done on proper UKAS-calibrated scales (similar to the American NIST). "Bathroom" scales have no place here, because we're talking about accuracy and legality.

Proper levelling is necesssary as well...I expect everyone's spirit level across the stabilser spars is calibrated to an International Standard, is it not?

As an aside, my reference above to 777lb for the 1945 BC12 is for a 1941 fuselage that was completed after the war with 15-rib truss ribs, and is the second-best Taylorcraft I have flown in terms of manoeuvrability & handling...the best was Dave Nuss's N26512. The light pre-wars are a joy to fly.

Rob

[3Dreaming]

Re: Taildragger tail dragging

Mike, if you do check the weight for real make sure to measure the actual arm for the weights with the airplane levelled up.