---------------------------------------------------------- Lightning-List Digest Archive --- Total Messages Posted Sat 02/23/08: 2 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 07:37 AM - Engine Cowl Cooling (jng62433@aol.com) 2. 04:03 PM - Re: Gear Leg Shimmy (JOSEPH MATHIAS LINDA MATHIAS) ________________________________ Message 1 _____________________________________ Time: 07:37:00 AM PST US Subject: Lightning-List: Engine Cowl Cooling From: jng62433@aol.com Lightning N166JG (Jim Goad) I now have 48 hours total on my lightning and things are going well.? The new tires helped the shimmy. I find a coincidence that there is a discussion on the cowl and engine cooling, because about 2 weeks ago I was looking up into the cowling opening near the nose landing gear supports on the motor mount.? I could see that the paint was rubbed off of the tubing near the back cowl lip. By pushing in the cowling back edge about 11/2" that was what had rubbed the paint off.? Apparently in flight the back edge of the middle of the cowling was being pushed in by air pressure.? It was an easy fix, all I did was hose clamp a stop on the tubing so that it holds the cowling out and prevents it from flexing upward. Jim Goad ________________________________________________________________________ ________________________________ Message 2 _____________________________________ Time: 04:03:38 PM PST US From: "JOSEPH MATHIAS LINDA MATHIAS" Subject: Re: Lightning-List: Gear Leg Shimmy Report on experiment # 2: Today we removed the wheels and axles from the Lightning; wrapped some shim material (beer can aluminum fits almost perfectly) around the axle and reinstalled the wheels. I then performed taxi tests; taxiing up to 33 kts ground speed, there was little to no shimmy. Ceiling never raised above pattern altitude all day so taxi was the only possibility. The slight roughness I felt at the highest speeds was probably the runway surface. I want to fly it a couple of times before I remove the aluminum angle Buz put on the gear then see if that makes any difference. However, between the upgraded tires and the axle shimming, we have greatly improved the situation. Assuming this continues to offer improvement, we will probably remove the shim material when it wears down and weld the axle into the socket to avoid having to periodically replace the shim material. Regards, Linda ----- Original Message ----- From: JOSEPH MATHIAS LINDA MATHIAS To: lightning-list@matronics.com Sent: Saturday, February 16, 2008 6:31 PM Subject: Lightning-List: Gear Leg Shimmy Well folks, we changed the tires on the main wheels today to Goodyear Flight Custom IIIs; one of the original tires definitely was out of round and quite obvious while spinning it on the axle during removal. The new tires improved the shimmy a bit but it hasn't gone away. However, we have a new theory: during the tire changing, we noticed that the axle is quite loose on both main gear. The next idea is to put some shim stock around the axle to tighten its fit in the socket. Has anyone else noticed that the axle doesn't fit tightly? I'll post the results when we get the axle tightened. Linda Mathias ------------------------------------------------------------------------- ----- ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message lightning-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Lightning-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/lightning-list Browse Digests http://www.matronics.com/digest/lightning-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.