The Taurus motor glider uses fluid to alter the C of G as per the quote below from http://www.mcp.com.au/sinus/models/taurus.html
"One of the unique features of the Taurus is the mass trim system. There are two fluid reservoirs in the aircraft, one in the nose and one in the tail section. Since both pilots sit in front of the CofG, the CofG range can move quite considerably. In case only one pilot is on board, the trim fluid is pumped into the front reservoir. Should there be 2 persons on board, the trim fluid is pumped into the tail section. By using the mass trim system the aircraft becomes safe and insensitive to big differences in pilot weights." Regards Barry Kruyssen Cairns, Australia RAA 19-3873 [email protected] http://www.users.bigpond.com/kr2/kr2.htm ----- Original Message ----- From: Brian Kraut To: KRnet Sent: Thursday, August 25, 2005 1:15 PM Subject: RE: KR> 56ML Incidence I have pondered the idea of having a couple pound weight on some type of pulley in the tail cone that could be moved forward or aft while in flight. You could arrange it so that your C.G. is correct with an almost empty header tank and a heavy passenger when the weight is moved forward. With just you and no passenger you could roll the weight towards the rear. Obviously, this is something that could cause an accident if it was put in the wrong position at the wrong time, moved by itself, or the weight broke off under heavy Gs and went sliding around. I don't know that the FAA would even allow it, but it is an interresting idea to ponder even if it was only set up temporarilly to explore performance at different C.G. locations while safely at altitude. I did notice that my KR was about 4 MPH faster when it was on the aft side of the safe limit than on the forward side of the safe limit. I also noticed that for a given C.G. location the speed was about the same regardless of my weight. I could achieve about the same C.G. location in a light loading with just me, fuel in the wing tanks, and a low header tank or a heavy loading with a full header, me and my son in the plane, and full wing tanks. Either way, speed was about the same, but climb rate differed. My Midget Mustang acts differently. I can't tell any difference at all in handling or speed with a full or very low header tank on it. Brian Kraut Engineering Alternatives, Inc. www.engalt.com -----Original Message----- From: [email protected] [mailto:[email protected]]On Behalf Of Steve Jacobs Sent: Wednesday, August 24, 2005 1:09 PM To: 'KRnet' Subject: RE: KR> 56ML Incidence I'm going to move the CG aft some (by moving the backup battery toward the tail, and maybe adding a few pounds of lead to the tail spring mount) and THEN I might adjust the horizontal stab. +++++++++++++++ Thanks, makes complete sense now. You really are fine-tuning this bird. = Having the CG float around (and within) the fwd part of the range is better, but you already know that. = If you must have a battery (or other heavy object) behind the seats, please secure it really well - these things become missiles in an accident. Consider finding a reason to make another engine mount or shortening the present mount by a few mm. (Won't be the first time you did something three times to get it perfect). When you get around to moving the prop and hub back a tad, that will also contribute without adding any weight, as will any weight you may save on the new cowl. Good luck Steve J _______________________________________ Search the KRnet Archives at http://www.maddyhome.com/krsrch/index.jsp to UNsubscribe from KRnet, send a message to [email protected] please see other KRnet info at http://www.krnet.org/info.html _______________________________________ Search the KRnet Archives at http://www.maddyhome.com/krsrch/index.jsp to UNsubscribe from KRnet, send a message to [email protected] please see other KRnet info at http://www.krnet.org/info.html
