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Collin
General
Gender: Male
Location: McMinnville. Oregon
Registered: Oct 2006
Status: Offline
Posts: 711
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 Posted Wednesday, April 20, 2011 @ 08:10 PM
Hello,
I added 5.5lb (2.5kg) weight when flying the RF5B solo. Without the weight I was running out up elevator. Trim about 70mph (113kph). With the weight running out of trim about 60-65mph (97-105kph).
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Jorgen
Captain
Gender: Male
Location: Lund, Sweden
Registered: Apr 2007
Status: Offline
Posts: 833
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Posted Thursday, April 21, 2011 @ 03:29 AM
Very neat Collin!
That's a good place to put the weight and easy to remove it. I have been thinking about a good place, it would be nice to be able to remove it for dual flights.
Inadvertedly you gave very good credibility to Nisse, a carpenter friend of mine who has done some work on Fourniers. Among the stories he has produced is a good one when he was using his axe to remove the rests of a tailwheel of an unfortunate RF 5 just as a Swedish FAA-inspector walks in the door. I asked him about running out of elevator in the RF 5b and putting a weight in the back. Off the top of his head he suggested 5 lb....
May the 4´s be with you/ Jörgen
P.S. I note with satisfaction that you provide both metric and US scale! D.S.
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Martin Hill
Sergeant
Gender: Male
Location: UK
Registered: Apr 2010
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Posts: 35
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Posted Thursday, April 21, 2011 @ 08:21 AM
How blindingly obvious. I was wondering about tail ballast and never thought to hang it on the handles!
The issue is elevator trim not necessarily cg position. Has anyone put a fixed tab on the other elevator to counter what seems a general "5" problem? I had noticed G-AZRK has one (to make gliding easier John once told me) and was thinking to do the same but wondered if this is a more widely adopted solution.
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Collin
General
Gender: Male
Location: McMinnville. Oregon
Registered: Oct 2006
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Posts: 711
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Posted Monday, April 25, 2011 @ 09:51 PM
Version 2
Flying with the 5.5lb (2.5kg) weight helped so I am making a heavier weight and streamlining.
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Jorgen
Captain
Gender: Male
Location: Lund, Sweden
Registered: Apr 2007
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Posts: 833
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Posted Tuesday, April 26, 2011 @ 04:04 AM
Haha Collin,
I was just going to ask about fairing the weight, but off course you already thought of that. Fourniers are gliders, so aerodynamics and fairings are part of the religion. Speaking of gliding, this spring is coming along nicely with unusually perky thermals, I had a 1 h 20 min flight with the 4 the other day, engine time 10 minutes and landed gliding. Strong lift on downwind and a windshift put me high and necessitated full spoilers and full slip on final. "Shake Yerbouti" as Mr Zappa put it.
May the 4´s be with you/ Jörgen
P.S. Eehrm Collin, I actually thought of a similar solution, but shouldn´t the eccentric hole be drilled close to the 12 o´clock position instead of as shown in the three o´clock, to keep the weight/fairing aligned in the slip stream? D.S.
[Edit by Jorgen on Tuesday, April 26, 2011 @ 04:11 AM]
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jb92563
Second Lieutenant
Gender: Male
Location: Lake Elsinore, CA, USA
Registered: Mar 2007
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Posts: 583
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Posted Tuesday, April 26, 2011 @ 10:10 AM
Nice work,
I was also going going to comment that an unstreamlined dumb bell hanging on the side of a glider just doesn't look right
but now it looks right.
An observation:
I am a little concerned about the location of the hole in the weight.
You should balance your little weight as if it were a wing with the cg & hole at about 25% of the chord so that it does not inadvertantly flip around on you during flight and cause any trim problems.
You might already have a method to prevent rotation of the weight on the handle but it was not obvious from the pictures.
--------------------
Ray
RF4D #4057 N-1771 Rectimo 1400cc
http://picasaweb.google.com/jb92563/FournierRF4D
http://www.touringmotorgliders.org
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Collin
General
Gender: Male
Location: McMinnville. Oregon
Registered: Oct 2006
Status: Offline
Posts: 711
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Posted Tuesday, April 26, 2011 @ 01:35 PM
Hi,
I plan on adding more weight to the tail section of the weight to balance out. (lead shot). I will drill two small holes to use the screw heads of the handle to keep from rotating.
More pictures will follow.
Collin
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Collin
General
Gender: Male
Location: McMinnville. Oregon
Registered: Oct 2006
Status: Offline
Posts: 711
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Posted Thursday, May 5, 2011 @ 06:26 PM
Hi,
Here is my new weight. 8.5lb (3.85kg)
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jb92563
Second Lieutenant
Gender: Male
Location: Lake Elsinore, CA, USA
Registered: Mar 2007
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Posts: 583
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Posted Friday, May 6, 2011 @ 12:58 PM
Nice looking aerodynamic weight. Now just paint it white so that it does not stand out against your paint job. 
--------------------
Ray
RF4D #4057 N-1771 Rectimo 1400cc
http://picasaweb.google.com/jb92563/FournierRF4D
http://www.touringmotorgliders.org
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Jorgen
Captain
Gender: Male
Location: Lund, Sweden
Registered: Apr 2007
Status: Offline
Posts: 833
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Posted Saturday, May 7, 2011 @ 04:15 AM
Neat Collin,
thanks for sharing your elegant solution. As an aside, "SE-UDI"s previous owner Peter in Borås said they didn´t use the handle to lift the tail because they feared the wooden screws would loosen, but since I have had plenty of opportunity to scrutinize the interior structure around the handle I feel confident it can handle(pun intended) the loads when lifting. Loosening wooden screws is a general Fournier characteristic anyway and needs to be dealt with on a regular basis.
Hi Martin, nice to have your input and sorry for not acknowledging your question. I haven´t heard of any additional tabs to fix the trim problem on RF 5b´s when flying solo and to be honest I don´t really see the point of adding the additional drag of a fixed tab to fix a problem that in my mind is a weight and balance issue. If you talk to John about his experience with G-AZRK I would be interested to hear about it.
Collin, I´m curious about the holes you talked about to keep it from rotating. Would you care to snap a picture of those? I´m so pleased to hear the twins don´t have to ride as counter weights everytime their dad goes flying- but I bet they are a lot more fun company!
May the 4´s be with you/ Jörgen
[Edit by Jorgen on Monday, May 9, 2011 @ 01:59 AM]
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Collin
General
Gender: Male
Location: McMinnville. Oregon
Registered: Oct 2006
Status: Offline
Posts: 711
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Posted Monday, August 1, 2011 @ 04:01 PM
Hi,
This picture was sent by Ron Smith. He and his twin Brother worked at Sportavia.
Note the jettisonable ballast.
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