Won't bore you with all the detail of how I got to this point but after a year I've only put about 10 hours on my Starduster (N249E), been through 3 tailwheel instructors, had a small fire behind the control panel and have recurring tailwheel issues. I would really appreciate some help.
When I received the plane it shimmied a bit and lacked some steering authority. Some of you noticed including Dave that the castor looked negative and should be corrected to positive. The mechanic rebuilt the Scott 3200 and removed a shim from the front of the tail spring and added a shim to the rear mount to create positive castor. He also changed the steering tension type connector springs to the Maule anti-shimmy connector springs. These compress instead of elongate when stretched.
About 12 weeks ago on a flight with my second instructor we got a really strong x-wind gust to which I responded with equally strong opposite rudder with limited response. When we reached the hanger, I noticed the tab on the Scott arm assembly was bent almost straight up. I bent it back down and considered it an anomaly. The next flight was uneventful.
The plane then went into annual during which the Scott 3200 was disassembled and inspected and the tailwheel itself was replaced due to some dry-rot. On the first landing after the annual, the tailwheel shimmied violently but did not shimmy at all during any of the subsequent 10 landings. However, there was very poor steering control during slow speed rollout and small wind gusts seemed to turn the plane easily. When we got to the hanger I found both of the Scott arms bent as pictured below.
The mechanic is recommending replacing the Scott standard arm assembly with a heavy duty arm assembly that has bent up tabs like the ones on Alaskan Bushwheels. I also noticed the castor was down to about + 1 deg with the plane empty and he suggested it should be + 4-7 degrees. He feels that the leaf spring may be worn out and should be replaced.
Questions:
1.) Is adding the heavy duty arm assembly the right thing to do? It seems like the angle from the rudder arm to the scott arm is quite steep which was exacerbated by the shims used to fix the caster. The heavy duty arm will lessen the angle and I really don't want to have another event where the arms get folded up. Also, should I install some eye bolts on the rudder arm to lower that connection and reduce the angle even further?
2.) What is the right replacement tail spring? I measured 1 1/2" width, the bolts as 3/8" Fuselage and 7/16" tail with a length following the curvature of a little more than 14". These match PN 06-14400 for the Aeronca but this spring is the wrong shape. Can the existing spring be re-bent by a shop?
3.) Should I keep the Maule anti-shimmy connector springs or should I switch back to standard tension type springs? My concern is that the maule type springs may be causing the scott arms to bend. I no longer have the old springs so if I should switch back, does someone have a part number?
Thanks in advance for any help. I really appreciate it.
When I received the plane it shimmied a bit and lacked some steering authority. Some of you noticed including Dave that the castor looked negative and should be corrected to positive. The mechanic rebuilt the Scott 3200 and removed a shim from the front of the tail spring and added a shim to the rear mount to create positive castor. He also changed the steering tension type connector springs to the Maule anti-shimmy connector springs. These compress instead of elongate when stretched.
About 12 weeks ago on a flight with my second instructor we got a really strong x-wind gust to which I responded with equally strong opposite rudder with limited response. When we reached the hanger, I noticed the tab on the Scott arm assembly was bent almost straight up. I bent it back down and considered it an anomaly. The next flight was uneventful.
The plane then went into annual during which the Scott 3200 was disassembled and inspected and the tailwheel itself was replaced due to some dry-rot. On the first landing after the annual, the tailwheel shimmied violently but did not shimmy at all during any of the subsequent 10 landings. However, there was very poor steering control during slow speed rollout and small wind gusts seemed to turn the plane easily. When we got to the hanger I found both of the Scott arms bent as pictured below.
The mechanic is recommending replacing the Scott standard arm assembly with a heavy duty arm assembly that has bent up tabs like the ones on Alaskan Bushwheels. I also noticed the castor was down to about + 1 deg with the plane empty and he suggested it should be + 4-7 degrees. He feels that the leaf spring may be worn out and should be replaced.
Questions:
1.) Is adding the heavy duty arm assembly the right thing to do? It seems like the angle from the rudder arm to the scott arm is quite steep which was exacerbated by the shims used to fix the caster. The heavy duty arm will lessen the angle and I really don't want to have another event where the arms get folded up. Also, should I install some eye bolts on the rudder arm to lower that connection and reduce the angle even further?
2.) What is the right replacement tail spring? I measured 1 1/2" width, the bolts as 3/8" Fuselage and 7/16" tail with a length following the curvature of a little more than 14". These match PN 06-14400 for the Aeronca but this spring is the wrong shape. Can the existing spring be re-bent by a shop?
3.) Should I keep the Maule anti-shimmy connector springs or should I switch back to standard tension type springs? My concern is that the maule type springs may be causing the scott arms to bend. I no longer have the old springs so if I should switch back, does someone have a part number?
Thanks in advance for any help. I really appreciate it.
