tailwheel broke off

[imolnar]

I am a proud new owner of a 1980 Taylorcraft F21, and I need your input. I bought this aircraft after not flying for 3 years. I transitioned from a C172, having 400 hours, and an instrument rating.
I just got my tailwheel endorsement this week. The plane had the original Maule tailwheel on it. Since I bought it, it had been shimmying pretty bad,and the clips holding the springs had to be replaced because they broke.

Today, on my fifth landing solo in a tailwheel the wheel broke off during landing (the fork broke where it attaches to the bearing). The landing was a bounce, not particularly hard, trew me off the runway into the grass. I was able to keep it straight, and there is no damage to the plane. I carefully taxied back to the hangar with a screatching noise behind me sliding on the remainder of the fork used to hold the wheel.

After talking with the mechanic on the field, I decided to replace the tailwheel and the leaf springs, but looking through Aircraft Spruce catalog, I am a bit confused what the right parts are. So I had a few questions to the forum:

1) The leafspring seems to be a 1 1/2", but there is no separate spring listed for F21, but one listed for the BC-12D. Is this leaf spring OK for the F21?
2) I do not wish to repeat this experience, so I would like to have a tailwheel, which will hold on to the rest of the aircraft.

Which one do you recommend? I am a bit confused about the choices, and their legality. I am considering the following, in order of preference: 1) Scott model 3200 with spacer to convert to 1 1/2#leafspring 2) Alaskan bushwheel ABI 3224A (standard), 3) Maule SFS-P8B1-2 (extra heavy duty), 4) Maule SFS-P8A1-2

thanks for any insight
istvan molnar

[jgerard]

Re: tailwheel broke off

the F21 and BC12D springs should be the same. Call Wup at alaska bushwheels if you want the 3200 series tail wheel. Costs lest and is better made than the scott one. OR the Maule tundra tail wheel. Both are strong enough to last quite a while.

[Marv]

Re: tailwheel broke off

That is the problem i have had with maule tailwheels. I went with
scott and never had any more trouble. Good luck. Marv

[dedrekon]

Re: tailwheel broke off

That's not all that uncommon on Maule Tailwheels. I had one break just like that. Upon closer inspection it was clear that there had been a hairline crack in the same spot where yours broke for a very long time.....you could see the discoloration difference between the final break and the crack. It wasn't even on a hard landing (don't make ‘em ). I make it a point to inspect that on a regular basis.
Now I have a Scott 3200 on one T and a regular Maule TW on the other. They're both fine (the Maule does shimmy, especially if you keep greased up to much), but I trust the Scott a lot more on rough terrain.
The Scott sits up a little higher and gives you better visibility over the nose (and less prop clearance) unless you have some big tires up front.
Speaking of which....does anybody have a 337 for putting 8's on a 65hp BC12D.....especially in the Portland FSDO? My tires are close to replacement and I'd like to go bigger....plus I have a set of 8's to put on it.

Vincent

[lfries]

Re: tailwheel broke off

I know my shimmy problems went away when ai replaced the maule with the scott. Currently working with a pilot in a Maule MX7-180 with a maule TW. We get a lot of shimmy. I'll have him contact the Alaska people for the price on a 3200 series.

[Jim Herpst]

Re: tailwheel broke off

Good grief. I always thought the Maul was a "good tough tail wheel" sounds like its real S#*t . Good to know

[Taylor Maid]

Re: tailwheel broke off

Dedrekon,

I too was looking to put some bigger tires on my t-craft. I called the local FSDO (GRR) and they said all I had to do was show them a weight and balance and fill out block 7 and another line on a 337 and I would be all set. I wound up getting lazy and never filled out the paperwork tho.

--Suzy

[high time cub]

Re: tailwheel broke off

[The Scott sits up a little higher and gives you better visibility over the nose (and less prop clearance)
Vincent[/SIZE][/FONT]

Vincent,
Do you find the higher tail wheel decreases your 3pt. attitude, therefore increasing stall landing speed and exacerbating float?
Jim

[fearofpavement]

Re: tailwheel broke off

Our BC-12D 100hp broke a tail wheel spring recently. It was the main leaf under the clamp and close inspection (ok, not that close) revealed it had been fractured and fretting for a while. It came apart while pushing it back into the tie down and thankfully did no damage to the rudder. Got a new leaf spring set from Aircraft Spruce and it's all better now.

Regarding the tailwheel shimmy, I have experienced that with several brands of tail wheel and think often the cause is more than just the brand of tail wheel. We currently have a Maule tailwheel on the T-craft and I haven't noticed shimmy but we rarely have it on pavement.

Used to fly a Decathalon that had an awful shimmy that we couldn't get to go away. It would wear the tread off a tailwheel tire in less than 20 hours. Don't know what they ever did to resolve it but hope so by now as that was a long time ago. (Scott wheel)

[crispy critter]

Re: tailwheel broke off

I know this is not t-craft but we have 3 Cessna 170's on the field and a Citabria,all have scott 3200 tailwheels on them. 2 of the C-170's have never shimmyed a single time however the other C-170 and the citabria both shimmy very,very bad if you 3 point them and sometimes when you wheel land them too(as the tail sets down). I have took both apart,inspected and reassembled but can't find anything worn or damaged.....any ideas to look for would be great.

[NC36061]

Re: tailwheel broke off

Istvan, do a search of the forum for past threads related to this problem. It is not uncommon, and can have various causes, including improper tailwheel geometry. You should be able to find some useful information in the archives.

Dave

[Dusty]

Re: tailwheel broke off

Shimmy is usually due to a flat tailspring. Replace it and no more shimmy.

Field approving a TSO or PMA tire less than 35x15 is about the easiest thing involving the FAA that you'll ever do. You have to put it on a scale (be prepared to gain some weight!), fly at a couple differerent weights, and sign your log book. Took me less that a day to get 26" Goodyears on the Champ, from asking my mechanic to signing my logbook.

http://www.safetydata.com/hbaw9701.htm

[N96337]

Re: tailwheel broke off

The shortwing Piper site has the best article (or at least had) on tailwheel shimmy I've ever read. The article goes through all the physics that are involved, and make it easy to understand what's happening, and once you understand, you can prevent it... it took me a few times reading it, but it's great! Mostly it has to do with the arch of the spring, the angle of the tailwheel pivot point, and the setup of the airplane. I'd strongly recommend it to anyone!!
As far as bigger tires, we've been able to do as Dusty did, and get them field approved, citing AC 23.733-1, and a couple simple "worksheets" that were provided to me by our local inspector. We also installed GarAero tundra tailwheels with the same procedure a bunch of times.
JH

[dedrekon]

Re: tailwheel broke off

Thanks for the good tire info! Do you perhaps have a copy of the "worksheets" you used?
I've not really had a problem "3 pointing" in a full stall with the taller tailwheels. I think it's pretty common in a full performance short landing for the tail wheel to hit the ground before the mains. You can get a pretty good angle of attack with the T if you practice your power on slow flight. I like to slip it almost to the ground, round out with some power in very high AOA and thunk it down as I close throttle. Taylorcrafts are all about energy management.
I'm curious as to the empty weight of the F21? How much useful load to you have? Also, what kind of performance do those extra 18 ponies add?

Vincent

[dewhitaker]

Re: tailwheel broke off

The Maule tailwheel is known to shimmy. The fix is to use the correct spring on each side for them. One spring should be heavier than the other, but I can't remember which side the heavier one goes on. Have to look in the paperwork that came with it. I had a large Maule that was put on by the owner before me. No shimmy problems. However, I did not like the way the plane looked with the larger tailwheel. We got a used Lang tailwheel and rebuilt it and I am very happy with it.