Tailwheel Steering
Moderators: GAHorn, Karl Towle, Bruce Fenstermacher
Tailwheel Steering
My recently purchased ragwing has very minimal tailwheel steering when taxiing, particularly to the left. When rolling out after landing and taxiing it is usually necessary to use the brake on the left side to stay straight. During a pre-purchase annual the left brake pad was quite a bit more worn than the right (they were installed at the same time) so this may have been going on for some time.
My mechanic has taken the tailwheel (Scott 3200) apart and inspected it and it is in good shape. He also tried switching the springs, which had no effect. Any ideas out there? Thanks! Kevin
My mechanic has taken the tailwheel (Scott 3200) apart and inspected it and it is in good shape. He also tried switching the springs, which had no effect. Any ideas out there? Thanks! Kevin
You mention needing to use the left brake to stay straight when taxiing. I had a similar problem with my "B" when I bought it. The plane had sat for some time previously and the right brake was partially seized. The puck had corrosion that prevented it from moving and caused it to be partially engaged all the time thereby requiring excessive opposite brake to compensate. Have a close look at your brakes and make sure they are not dragging.
My $.02
My $.02
Doug
- Bruce Fenstermacher
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- Kyle Wolfe
- Posts: 706
- Joined: Mon Mar 17, 2003 12:30 am
I don't have my parts book at home so I can't provide you with the appropriate parts number, but I had a similar problem not wanting to turn to the left.
Check the spring in the tailwheel which looks like this \___/ Mine was a bit too long and was not engaging into the v-notch in the tailwheel. So when pushing on the rudders the cables would tighten and apply pressure, but since the spring was not engaging into the notch it simply slid by and would not turn the tailwheel in direction. Make certain this spring is engaging the slot.
Check the spring in the tailwheel which looks like this \___/ Mine was a bit too long and was not engaging into the v-notch in the tailwheel. So when pushing on the rudders the cables would tighten and apply pressure, but since the spring was not engaging into the notch it simply slid by and would not turn the tailwheel in direction. Make certain this spring is engaging the slot.
Kyle
54 B N1932C
57 BMW Isetta
Best original 170B - Dearborn, MI 2005
54 B N1932C
57 BMW Isetta
Best original 170B - Dearborn, MI 2005
Kevin, you will find that even if there isn't anything wrong with your tail wheel steering you will still have very minimal tail wheel steering just by its design. However it shouldn't be just to one side. You'll find that good brakes are a must. Wait untill you try taxiing on skis with no brakes. You don't realize how much you need them until they are gone. If you get in a little crosswind while taxiing on skis it can become impossible with out having someone walk the tail for you. Good luck!
Shawn
Shawn
With your tailwheel locked lift the tail to see if it is alignment with your rudder. Hows your main gear alignment?
Vic
N2609V
48 Ragwing
A Lanber 2097 12 gauge O/U Sporting
A happy go lucky Ruger Red label 20 ga
12N Aeroflex
Andover NJ
http://www.sandhillaviation.com
![Image](http://vicsviewaviation.com/inflight170.jpg)
" Air is free untill you have to move it" BB.
N2609V
48 Ragwing
A Lanber 2097 12 gauge O/U Sporting
A happy go lucky Ruger Red label 20 ga
12N Aeroflex
Andover NJ
http://www.sandhillaviation.com
![Image](http://vicsviewaviation.com/inflight170.jpg)
" Air is free untill you have to move it" BB.
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- Posts: 2271
- Joined: Tue Apr 23, 2002 12:11 am
A quick & dirty way to check wheel alignment:
1) Put a straight-edge across the front of both main-gear tires, up on a couple blocks ( like on 4 x 4's)
2) Use a long-ish framing or combination square to check the flat inboard side of the brake disc's against the straight-edge. With the airplane loaded up to 2,000 pounds,ideally the disc's should be square to the straight-edge--in other words,neutral castor (zero toe-in/toe-out). I'm not too sure how much effect positive/negative camber has on handling-- I think that's more a tire-wear thing.
My ragwing has neutral castor and positive camber ( top of wheels tilted out) at around 1550 pounds-- in other words,ready to fly but with no people on board yet-- and it seems to handle fine.
Eric
1) Put a straight-edge across the front of both main-gear tires, up on a couple blocks ( like on 4 x 4's)
2) Use a long-ish framing or combination square to check the flat inboard side of the brake disc's against the straight-edge. With the airplane loaded up to 2,000 pounds,ideally the disc's should be square to the straight-edge--in other words,neutral castor (zero toe-in/toe-out). I'm not too sure how much effect positive/negative camber has on handling-- I think that's more a tire-wear thing.
My ragwing has neutral castor and positive camber ( top of wheels tilted out) at around 1550 pounds-- in other words,ready to fly but with no people on board yet-- and it seems to handle fine.
Eric
-
- Posts: 2271
- Joined: Tue Apr 23, 2002 12:11 am
Check the spring in the tailwheel which looks like this \___/ Mine was a bit too long and was not engaging into the v-notch in the tailwheel. So when pushing on the rudders the cables would tighten and apply pressure, but since the spring was not engaging into the notch it simply slid by and would not turn the tailwheel in direction. Make certain this spring is engaging the slot.
There are two shims or spacers that go with that spring. It is important the thicker is installed "inboard." I found that it made a big difference, and corrected my steering problem.
There are two shims or spacers that go with that spring. It is important the thicker is installed "inboard." I found that it made a big difference, and corrected my steering problem.
Sorry, folks, but tracking the main gear isn't quite that easy. What's been outlined to this point is a good starting point, but the definitive procedure to determine main gear track is to put the airplane on grease plates. It isn't necessarily the airplane at rest, sitting in the three point attitude that you necessarily need to look at. Cessna gear moves in many directions during any landing roll.
The problem with the technique described to date is that all it does is measures where the wheels are relative to what the airplane did last. Friction is a wonderful force, and will massively influence the results you see using this procedure. Roll the airplane backward first, and the wheels will point one direction. Roll it forward first, and they'll point in the opposite direction, etc.
Find a good Cessna tailwheel mechanic who understands working the airplane through a grease plate process, and you WILL find a huge difference. Basically, they take four plates of steel, put grease between each pair, then set the airplane down on the grease plates with a hoist.
The grease plates take the friction issue out of the picture, and tell you what your gear is actually wanting to do. Without the grease plates, you'll never know if what you are seeing is simply an artifact of friction.
Mechanics hate the grease plate program, because it requires a lot of messing around with the shims behind the axles to get the gear aligned.
DO IT, THOUGH!! I know of at least one C-170 owner who was about to sell his airplane till he had it done, and wound up in love again.
My airplane was badly out of track, and a semi-handful on pavement.
Also, exchange your tailwheel steering arm (and dust caps) for a Scott 3214T steering arm. It has upturned steering arms, and MUCH better steering geometry. Add to that compression steering springs, and you'll have a much better steering airplane.
Stock 170's don't steer well, and I've heard people say to just accept that. BS, you can make it better, and it doesn't cost that much or take that much trouble.
Mike Vivion
The problem with the technique described to date is that all it does is measures where the wheels are relative to what the airplane did last. Friction is a wonderful force, and will massively influence the results you see using this procedure. Roll the airplane backward first, and the wheels will point one direction. Roll it forward first, and they'll point in the opposite direction, etc.
Find a good Cessna tailwheel mechanic who understands working the airplane through a grease plate process, and you WILL find a huge difference. Basically, they take four plates of steel, put grease between each pair, then set the airplane down on the grease plates with a hoist.
The grease plates take the friction issue out of the picture, and tell you what your gear is actually wanting to do. Without the grease plates, you'll never know if what you are seeing is simply an artifact of friction.
Mechanics hate the grease plate program, because it requires a lot of messing around with the shims behind the axles to get the gear aligned.
DO IT, THOUGH!! I know of at least one C-170 owner who was about to sell his airplane till he had it done, and wound up in love again.
My airplane was badly out of track, and a semi-handful on pavement.
Also, exchange your tailwheel steering arm (and dust caps) for a Scott 3214T steering arm. It has upturned steering arms, and MUCH better steering geometry. Add to that compression steering springs, and you'll have a much better steering airplane.
Stock 170's don't steer well, and I've heard people say to just accept that. BS, you can make it better, and it doesn't cost that much or take that much trouble.
Mike Vivion