This confusion is common. It arises when people try to visualise the angle beta by simply yawing the aircraft, which they at the same time visualise as flying straight in the original direction. (you get the same condition if you yaw the aircraft in a wind tunnel)
In this special case beta equals minus yaw angle - which is why they make this mistake. In turning flight there is of course no such simple relationship between sideslip and yaw. Side slip angle beta has the same sign as side slip velocity v. Alan -----Original Message----- From: Jon S. Berndt Sent: Monday, July 29, 2013 1:54 PM To: 'FlightGear developers discussions' Subject: Re: [Flightgear-devel] making sign of side-slip consistent betweenfdm (bug 901) As in this image: http://dodlithr.blogspot.com/2011/09/airplanes-stability-axis.html Beta is positive when the wind hits the right side of the vehicle. This is the only standard convention I have ever seen. I would recommend strongly against artificially changing the sign of this parameter as output from JSBSim. Jon > -----Original Message----- > From: jean pellotier [mailto:jean.pellot...@wanadoo.fr] > Sent: Monday, July 29, 2013 6:27 AM > To: FlightGear developers discussions > Subject: [Flightgear-devel] making sign of side-slip consistent between > fdm (bug 901) > > hi there, > > following this bug report: > > http://code.google.com/p/flightgear-bugs/issues/detail?id=901 > > it appears that orientation/side-slip-deg and side-slip-rad don't have > the same sign, depending if it's a yasim or a jsbsim plane. > > is there a commonly adopted convention for this property? > > if not, shouldn't we document somewhere the meaning of the different > fdm properties present in fg tree, to avoid such problems in the future > ? > > jano > > ----------------------------------------------------------------------- > ------- > See everything from the browser to the database with AppDynamics Get > end-to-end visibility with application monitoring from AppDynamics > Isolate bottlenecks and diagnose root cause in seconds. > Start your free trial of AppDynamics Pro today! > http://pubads.g.doubleclick.net/gampad/clk?id=48808831&iu=/4140/ostg.cl > ktrk > _______________________________________________ > Flightgear-devel mailing list > Flightgear-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/flightgear-devel ------------------------------------------------------------------------------ See everything from the browser to the database with AppDynamics Get end-to-end visibility with application monitoring from AppDynamics Isolate bottlenecks and diagnose root cause in seconds. Start your free trial of AppDynamics Pro today! http://pubads.g.doubleclick.net/gampad/clk?id=48808831&iu=/4140/ostg.clktrk _______________________________________________ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel ------------------------------------------------------------------------------ See everything from the browser to the database with AppDynamics Get end-to-end visibility with application monitoring from AppDynamics Isolate bottlenecks and diagnose root cause in seconds. Start your free trial of AppDynamics Pro today! http://pubads.g.doubleclick.net/gampad/clk?id=48808831&iu=/4140/ostg.clktrk _______________________________________________ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
