Taildragger tail dragging

[1938BF50]

I recently bought a 1940 BC-12 Taylorcraft that for all practical purposes has been converted to a BC-12D. BC-12D wings and 2-hinge tail surfaces were added at some point in its history(1950’s if I remember correctly). It flies wonderfully and will fly hands off with minor trim adjustments. On my test flight(and departure) in the plane, I noted that the tail never came up on takeoff. It lifted off semi-3pt. Never thought much more about it until I rec’d some recent feedback that my tailwheel is still on the ground long after the mains have lifted. I make the comparison to my 1938 which would lift the tail in under 100ft.
So here is my question……could wash affect the take-off this much? I will look at W&B tonite and post those figures for reference. Hopefully, this weekend I can spend some more time with it. I plan to measure wash, remove the Maule, and replace it with the Heath. I will also inspect the tail-section for a mud or sand build-up. Any other obvious things that I might be missing?
MikeC

[Pearson]

Re: Taildragger tail dragging

Mike,
Congratulations on the new plane. As usual there are always a few little things that need attention when you buy a used airplane. I think you are on the right course of action in looking for anything that might add weight in the tail area of your plane. You could start by just putting a scale under the tailwheel and comparing it with other Taylorcraft. I am no engineer, but I don't think the wash out could affect the tail being heavy to this degree. If you don't find any sort of added weight in the tail area, I would suggest looking for an improper repair. I would suggest taking some very accurate measurements of where the horizontal stab attaches to the fuselage. Someone may have done a repair and not put the stab back on at the correct angle. As usual, always look for the simplest solution. I would be extremely careful about flying this plane until the problem is found and fixed. If you accidentally stall, or just get a little too slow, it could be deadly.

[Hank Jarrett]

Re: Taildragger tail dragging

Richard is saying be cautious, I will REDOUBLE THAT! DO NOT FLY until you weigh her! It is nice to look at the W&B paperwork, but NEVER trust it when you buy a plane. When you do your W&B you will KNOW where the CG is. When I bought my 41 the W&B had been copied from the original paperwork from the factory, and since it showed EXACTLY the same weight as the TC I doubt the factory actually weighed it. When I checked it I was at the very aft limit for CG. A bottle of water in the baggage sling put me outside of limits! NICE crisp controls, but I pulled about 20# of old wire out of the fuselage that wasn't hooked to anything. Loads of old lamp and extension cord back there and a piece of PVC tube painted to look like a longeron under the fairing under the pilots door. It was PACKED with wire. The battery had also been moved from in front of the seat kick plate to a plate behind the baggage compartment. If I had tried a spin I seriously doubt I could have recovered if anything was in the baggage compartment.

A W&B is easy to do and I for one would like to hear where your CG is. Check the incidence angle of the wing with the stab level too. That will tell you if the fuselage is bent from a bad repair.

Hank

[M Towsley]

Re: Taildragger tail dragging

Check your elevator trim that is is not giving you a little 'up' elevator.

[jim cooper]

Re: Taildragger tail dragging

After making sure there weren't any old corn binder parts or rolls of barb wire in the rear of the fuselage and that the tail was fastened on correctly, I would set the trim in neutral position and take off. ( You mentioned it flew very nicely and trimmed perfectly) when I arrived at 2500 feet I would trim it out and look at the trim indicator to see where it was. It may have slipped on the pulley giving a false reading. Slow fly it, stall it,etc. Land and take off again with necessary forward pressure to raise the nose. None of my three ever had the tail come up immed. I ALWAYS had to apply some forward pressure, or just fly it off tail low. Personally I don't think the tail wheel model has anything to do with it. None of my three ever flew exactly the same. If it was annualed by someone you trust , I'd fly it some and check it out. Best, JC ( I think Marty's point has alot of merit.)

[crispy critter]

Re: Taildragger tail dragging

Improper washout could also cause it but not likely....the airplane has been in the high mountains so it could be rigged for a much higher angle of attach then you will probably every be flying at again so it might simply need to be rigged back down to earth,lol.

A stock postwar taylorcraft with wood prop is a little toward the tail heavy side anyway from the factory. Check your actual w&b, check the rigging, check for extra weight toward the tail(make sure you check under the seat and baggage sling/floor too).

Something else ya might check....first does the airplane seem to be landing normally, trimming out and flying like it should in level flight, feels normal in steep turn etc.? If so and everything else checks out them you might trying checking the angle of thrust on the engine. I the engine mount is warped or bent it could cause the engine thrust line to angle up a little bit which would be most noticeable on takeoff and climb out. Also check your engine mount bushings, bolts, etc. Hope this helps.

[1938BF50]

Re: Taildragger tail dragging

I will weigh it this weekend. The current paper shows a 63# tailwheel weight. Is this in the ballpark with some other 12D Taylorcrafts out there?

[Guest]

Re: Taildragger tail dragging

mine is 70 lbs. with full fuel in nose

[Robert Lees]

Re: Taildragger tail dragging

Mike:

Here are some tail weights I have measured in the last few years:

1945 BC12 50lb (A-65 engine) Empty weight 777lb [PX]
1946 BC12-D 63.5lb (A-65 engine) Empty weight 828lb [EY]
1946 BC12-D 58lb (A-65 engine) Empty weight 814lb [EY]
1946 BC12-D 58lb (C-85 engine) Empty weight 839lb [EY]
1946 BC12-D 65lb (A-65 engine) Empty weight 855lb [IH]
1946 BC12-D 62lb (A-65 engine) Empty weight 877lb [NR]



The letters in italics are for my reference [Registrations]. All carried out with empty tanks (or at least, the "unusable" fuel").

So it sounds like you are in the right ballpark. But Drude's sounds wrong...full fuel in the nose should reduce the tail wheel weight.

Rob

[1938BF50]

Re: Taildragger tail dragging

Thanx Rob!
I am starting to feel better about 27599's EW @ 770#. I was comparing it to my 20407's EW of 680#.

Wow.......your listing of 1946 BC12-D 62lb (A-65 engine) Empty weight 877lb [NR]) would allow me full fuel and a 21# payload!

[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.

[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

[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

[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.

[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