---------------------------------------------------------- Allegro-List Digest Archive --- Total Messages Posted Sun 12/16/07: 3 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 11:55 AM - Electric Flaps - Incident (Hugh) 2. 02:49 PM - Micro switch replacement parts (Amy Hackworth) 3. 05:17 PM - Re: Micro switch replacement parts (Hugh) ________________________________ Message 1 _____________________________________ Time: 11:55:56 AM PST US From: "Hugh" Subject: Allegro-List: Electric Flaps - Incident Everyone, The other day as I and my instructor were flying my Allegro 2000, we had an incident with the electric flap drive that I felt was worth sharing. Having made a short flight (10 miles) to a different field, landed, and taken back off, I had returned to my home field and landed, and taken off twice and was landing the third time when the plane began to behave very differently on final. I made the landing alright although it probably was not very pretty. After we came to a stop my instructor and I looked at each other and we agreed on "let's try that again". Well, as I began my pre-takeoff checks and got to the point where I set the flaps to take off position, I looked out the window as I turned the switch to position 1, and the flaps did not move. They were in position "0". I tried again and they did not move. I then noticed the flaps breaker on the panel was tripped. I reset the breaker and tried again, and the breaker tripped. Well that ended that days flying. After returning to the hanger I checked the flap servomotor drive, and limit switches. As I removed the protective cover I saw the drive was at the top position, and the spring loaded metal trip plate was at the top micro switch and slightly to the side. It was enough for the trip plate to miss the switch. Some how the Potter & Brumfield breaker tripped the circuit before the drive motor drove the vertical rod any farther. I was able to get the motor to re-position the drive to position "1". The trip plate was still in its original position on the worm gear drive unit, and tight. After trying all three positions again I noticed that each time the flap switch was activated and the motor torque began to drive the worm gear, the whole worm gear drive rotated a slight amount. I knew about this earlier when setting up the flap drive. In fact, I had earlier shimmed (with washers) the upper forked end of the vertical flap rod where it fits over the bearing of the flap lever to take the rotational play (there is some unless you shim it) out of the rod. The shims were still in place and the rod was tight. However, when I activated the drive I noticed some slight rotation of the worm gear drive unit (the red cylinder) before the vertical movement began. This occurred in the up and down direction. This slight rotation combined with the narrow width of the spring loaded metal trip plate had allowed the trip plate to rotate enough to slightly miss the micro switch. I don't know why this rotational movement is occurring in the worm gear drive unit, other than normal play between the gear drive and the worm gear. To correct this problem I have fabricated a small metal piece that I have riveted on the end of the metal trip plate that is wider than the original trip plate width. This wider piece takes into account the slight rotation that is occurring and assures that the micro switches do come in contact with the trip plate, and properly trip the drive unit. Also, if one had to replace one of these micro switches, does anyone know what brand, type, model Number, etc., they are? Each of you might want to check your drive units to see if you are getting this same type rotation (or play), and determine if it could be a problem in the future. If any one is interested I can post a photograph of the "fix". Hugh McKay in NC Allegro 2000 Rotax 912 UL N661WW ________________________________ Message 2 _____________________________________ Time: 02:49:20 PM PST US From: "Amy Hackworth" Subject: Allegro-List: Micro switch replacement parts Hey Hugh, Dale & I had the same problem with the switch plate missing the micro switch. Fortunately, we learned of this problem before the plane was even airworthy. Dale also has shimmed the upper bearing (hopefully enough). In our case, the micro switch broke and we were really concerned about waiting for another to arrive from Czech Republic. After some research, we found a place in California called All Electronics. They were very accommodating and we received our part here in Florida within a couple of days. Here is the info: All Electronics, Van Nuys, CA 1-800-826-5432 www.allelectronics.com Item #SMS-219 SPDT Mini Snap Action Switch w/ Roller Lever $1.30 each (shipping & handling was $7) We had given this information to B-Bar-D Aviation some time back, so they may have some in stock. Best Wishes, Amy & Dale Hackworth Allegro Amphib 306AD (now has 20 hours on the Hobbs!) ________________________________ Message 3 _____________________________________ Time: 05:17:15 PM PST US From: "Hugh" Subject: RE: Allegro-List: Micro switch replacement parts Amy/Dale: Thanks so much for the info on where to get the switches. Did your switch fit exactly in the same location as the old one without problems? Hugh _____ From: owner-allegro-list-server@matronics.com [mailto:owner-allegro-list-server@matronics.com] On Behalf Of Amy Hackworth Sent: Sunday, December 16, 2007 5:49 PM Subject: Allegro-List: Micro switch replacement parts Hey Hugh, Dale & I had the same problem with the switch plate missing the micro switch. Fortunately, we learned of this problem before the plane was even airworthy. Dale also has shimmed the upper bearing (hopefully enough). In our case, the micro switch broke and we were really concerned about waiting for another to arrive from Czech Republic. After some research, we found a place in California called All Electronics. They were very accommodating and we received our part here in Florida within a couple of days. Here is the info: All Electronics, Van Nuys, CA 1-800-826-5432 www.allelectronics.com Item #SMS-219 SPDT Mini Snap Action Switch w/ Roller Lever $1.30 each (shipping & handling was $7) We had given this information to B-Bar-D Aviation some time back, so they may have some in stock. Best Wishes, Amy & Dale Hackworth Allegro Amphib 306AD (now has 20 hours on the Hobbs!) ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message allegro-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Allegro-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/allegro-list Browse Digests http://www.matronics.com/digest/allegro-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.