Re: [Flightgear-devel] Aircraft and Debian Packages
1) Have you got the scripts? would look to see how its done. Yes, you first have to use the: http://brisa.homelinux.net/fgfs/download_and_compile-2.0.0.sh (save it in an empty folder and run it) to have fgfs 2.0 up and runnning then: http://brisa.homelinux.net/fgfs/debCreator-2.0.0.tar.gz unpackit and change the fift line ORI_PATH= to point to the folder you build FlightGear run it. it will recompile and build packages. 2) As far as where to put them, Launchpad PPA's would be an obvious choice. I would like to do it, but it seems to me you have to work with src debs, and you can't send them binary debs. And since these are not programs, bat data for FlightGear don't know what to do. 3) Can the deb's be created via an automated process.. eg check is changed in cvs, make package, upload. There is an other script that creates packages for cvs version, the script compare the compilation folder with the local folder and if it finds files differences it will build a new package for aircraft with new version number. here: http://brisa.homelinux.net/fgfs/download_and_compile.sh and after: http://brisa.homelinux.net/fgfs/debCreator.tar.gz If any problem, let me know. pete Cheers Francesco -- Download Intel#174; Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] Airliners and Auto Pitch-Trim
Hi Guys I think you will find on all Boeing aircraft if the elevator is out of neutral for a set amount of time the horizontal stabilizer runs to return the elevator to the null position.Hence retriming the aircraft.Hence the name stabilizer trim I think also you will find that the tab on the elevator is not a trim tab but moves in the opposite direction to the elevator movement. So until we get a working FDM for the horizontal stabilizer in FG anything else will be a hack. Cheers Innis Hi, I just tried with the SenceaII and both Ti and elevator filter influence this. Great, thanks to all for the help! Cheers Heiko If you have a pid-simple-controller, try increasing Ti, it slows down the action. Hi Torsten, That sounds like it could be done without nasal just in the autopilot file. I guess the speed of the trim-pitch-channel can be changed with the filter? (The 737-300 has a speed-trim at certain situations) Kind regards Heiko Hi Heiko, the auto-pitch-trim channel moves the elevator trim to return the elevator into the neutral position while the pitch-channel moves the elevator to change attitude. Or a bit more technical: The auto-pitch-trim-channel compares the elevator-pos-norm to a reference of zero and adjusts elevator-trim The pitch-channel compares e.g. current pitch with a reference of some calculated target pitch and adjusts elevator-pos Usually the pitch-trim channel is much slower than the elevator channel. HTH, Torsten -- Download Intel® Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel __ Do You Yahoo!? Sie sind Spam leid? Yahoo! Mail verfügt über einen herausragenden Schutz gegen Massenmails. http://mail.yahoo.com -- Download Intel® Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel -- Download Intel® Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel __ Do You Yahoo!? Sie sind Spam leid? Yahoo! Mail verfügt über einen herausragenden Schutz gegen Massenmails. http://mail.yahoo.com -- Download Intel#174; Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel _ Get personal with Windows. Download a free gift for your PC. http://experience.windows.com-- Download Intel#174; Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] Airliners and Auto Pitch-Trim
On Sun, 7 Mar 2010 20:29:55 +0800, Innis wrote in message blu131-w17c7e956211e458dacc7f2df...@phx.gbl: Hi Guys I think you will find on all Boeing aircraft if the elevator is out of neutral for a set amount of time the horizontal stabilizer runs to return the elevator to the null position.Hence retriming the aircraft.Hence the name stabilizer trim I think also you will find that the tab on the elevator is not a trim tab but moves in the opposite direction to the elevator movement. ..those tabs are 'servo rudders', the essentially fly the elevators etc they hang on to, not the plane, etc for rudders, ailerons etc. They are often _combined_ with trim tab controls, though. So until we get a working FDM for the horizontal stabilizer in FG anything else will be a hack. ..maybe a tree of sub-FDM's? Cheers Innis Hi, I just tried with the SenceaII and both Ti and elevator filter influence this. Great, thanks to all for the help! Cheers Heiko If you have a pid-simple-controller, try increasing Ti, it slows down the action. Hi Torsten, That sounds like it could be done without nasal just in the autopilot file. I guess the speed of the trim-pitch-channel can be changed with the filter? (The 737-300 has a speed-trim at certain situations) Kind regards Heiko Hi Heiko, the auto-pitch-trim channel moves the elevator trim to return the elevator into the neutral position while the pitch-channel moves the elevator to change attitude. Or a bit more technical: The auto-pitch-trim-channel compares the elevator-pos-norm to a reference of zero and adjusts elevator-trim The pitch-channel compares e.g. current pitch with a reference of some calculated target pitch and adjusts elevator-pos Usually the pitch-trim channel is much slower than the elevator channel. HTH, Torsten -- Download Intel® Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel __ Do You Yahoo!? Sie sind Spam leid? Yahoo! Mail verfügt über einen herausragenden Schutz gegen Massenmails. http://mail.yahoo.com -- Download Intel® Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel -- Download Intel® Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel __ Do You Yahoo!? Sie sind Spam leid? Yahoo! Mail verfügt über einen herausragenden Schutz gegen Massenmails. http://mail.yahoo.com -- Download Intel#174; Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel _ Get personal with Windows. Download a free gift for your PC. http://experience.windows.com -- ..med vennlig hilsen = with Kind Regards from Arnt... ;o) ...with a number of polar bear hunters in
Re: [Flightgear-devel] Airliners and Auto Pitch-Trim
Hi, Hi Guys I think you will find on all Boeing aircraft if the elevator is out of neutral for a set amount of time the horizontal stabilizer runs to return the elevator to the null position.Hence retriming the aircraft.Hence the name stabilizer trim I think also you will find that the tab on the elevator is not a trim tab but moves in the opposite direction to the elevator movement. The tabs are to support the movements of the control surfaces and in the case there is no hydraulic pressure anymore. With other words- when no hydraulic only the small tabs are moved so due to the aerodynamic forces the whole control surface is moving in the opposite way. No idea if JSBSim can simulate this. Only at older jets, the newer ones has another system for hydraulic backup in case of emergency. The whole stabilizer is the pitch trim. Before start the aircraft has to be trimmed according to CoG. Without the aircraft would never rotate at the given Vr. At low weight; low speed, aft CoG and some more conditions the 737 uses a so called Auto-speedtrim which is twice as fast as the usual Autotrim and electric trim. I was now able to make the Autotrim,(run the elevator to zero-position) Autospeedtrim is still missing yet. My question to JSBSim- folks here: Is JSBSim able to to simulate the forces of the whole stabilizer trim? I used the usual trim for the 737-300, but have problems to match the settings according to the the real one ( I have already found a table wich shows me the angle of the stab related to the trim settings) Cheers Heiko __ Do You Yahoo!? Sie sind Spam leid? Yahoo! Mail verfügt über einen herausragenden Schutz gegen Massenmails. http://mail.yahoo.com -- Download Intel#174; Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
[Flightgear-devel] Shader question
Hi Tim, is there a way to have the value of an uniform updated every frame by the value of a live property ? I used : parameters sun-angleuse/sim/time/sun-angle-rad/use/sun-angle /parameters and then, in pass uniform namesun_angle/name typefloat/type valueusesun-angle/use/value /uniform According to README.effect, the value should dynamically change but my shader variable stay at 0.0. The readme also says [NOT IMPLEMENTED YET], but it is unclear to me what in not implemented : the copy of a value from the global property tree to a uniform, or the copy from a local property, or both ? Regards, -Fred -- Download Intel#174; Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] Shader question
On Sun, Mar 7, 2010 at 6:37 PM, Frederic Bouvier fredfgf...@free.fr wrote: Hi Tim, is there a way to have the value of an uniform updated every frame by the value of a live property ? I've been promising this to AndersG for some time now. I have code that basically makes this (the animation) work in my development tree, but haven't checked it in yet. I'll check it in for uniforms tonight, then start changing the code to support animations in the other effects parameters too. Tim I used : parameters sun-angleuse/sim/time/sun-angle-rad/use/sun-angle /parameters and then, in pass uniform namesun_angle/name typefloat/type valueusesun-angle/use/value /uniform According to README.effect, the value should dynamically change but my shader variable stay at 0.0. The readme also says [NOT IMPLEMENTED YET], but it is unclear to me what in not implemented : the copy of a value from the global property tree to a uniform, or the copy from a local property, or both ? Initializing a value from a property works, animating it doesn't. Regards, -Fred -- Download Intel#174; Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel -- Download Intel#174; Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] Airliners and Auto Pitch-Trim
The tabs are to support the movements of the control surfaces and in the case there is no hydraulic pressure anymore. With other words- when no hydraulic only the small tabs are moved so due to the aerodynamic forces the whole control surface is moving in the opposite way. No idea if JSBSim can simulate this. Only at older jets, the newer ones has another system for hydraulic backup in case of emergency. The whole stabilizer is the pitch trim. Before start the aircraft has to be trimmed according to CoG. Without the aircraft would never rotate at the given Vr. At low weight; low speed, aft CoG and some more conditions the 737 uses a so called Auto-speedtrim which is twice as fast as the usual Autotrim and electric trim. I was now able to make the Autotrim,(run the elevator to zero-position) Autospeedtrim is still missing yet. My question to JSBSim- folks here: Is JSBSim able to to simulate the forces of the whole stabilizer trim? I used the usual trim for the 737-300, but have problems to match the settings according to the the real one ( I have already found a table wich shows me the angle of the stab related to the trim settings) Cheers Heiko Hi, Heiko, The short answer is, yes, of course. The longer answer is even more emphatically, yes, but I'm on the way out right now. Will have to respond later in more detail if others have not. Jon -- Download Intel#174; Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] Airliners and Auto Pitch-Trim
On Sun, 2010-03-07 at 15:15 +, Heiko Schulz wrote: Hi, Hi Guys I think you will find on all Boeing aircraft if the elevator is out of neutral for a set amount of time the horizontal stabilizer runs to return the elevator to the null position.Hence retriming the aircraft.Hence the name stabilizer trim I think also you will find that the tab on the elevator is not a trim tab but moves in the opposite direction to the elevator movement. The tabs are to support the movements of the control surfaces and in the case there is no hydraulic pressure anymore. With other words- when no hydraulic only the small tabs are moved so due to the aerodynamic forces the whole control surface is moving in the opposite way. No idea if JSBSim can simulate this. Only at older jets, the newer ones has another system for hydraulic backup in case of emergency. Seems to me I remember a crash report where a DC10?'s center engine shelled and cut all the hydraulic lines leading to a total loss of hydraulics. Yeah, there it is: http://en.wikipedia.org/wiki/United_Airlines_Flight_232 The whole stabilizer is the pitch trim. Before start the aircraft has to be trimmed according to CoG. Without the aircraft would never rotate at the given Vr. At low weight; low speed, aft CoG and some more conditions the 737 uses a so called Auto-speedtrim which is twice as fast as the usual Autotrim and electric trim. I was now able to make the Autotrim,(run the elevator to zero-position) Autospeedtrim is still missing yet. My question to JSBSim- folks here: Is JSBSim able to to simulate the forces of the whole stabilizer trim? I used the usual trim for the 737-300, but have problems to match the settings according to the the real one ( I have already found a table wich shows me the angle of the stab related to the trim settings) Cheers Heiko JSBSim can pretty much simulate anything if you get the math and functions right... So, if I understand correctly, we want to keep the elevator control and elevator trim, then add the ability to rotate the entire horizontal stabilizer? For simplicity break the problem down into two areas: - Flight controls driving the surface positions -- Elevator position (currently): fcs/elevator-pos-rad = (fcs/elevator-cmd-norm + fcs/pitch-trim-cmd-norm) * 0.3 -- Stabilizer position (create a new property or two) fcs/stabilizer-cmd-norm fcs/stabilizer-pos-rad - Aerodynamic effects of surface positions -- Add functions for change in Lift, Drag and Pitch due to Stabilizer position. Ron -- Download Intel#174; Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] Airliners and Auto Pitch-Trim
Hi, I have no experience in FGFS capabilities in terms of autopilot and trimming, but I do have some in JSBSim, so I will refer only to that FDM, and I hope this will be relevant to this discussion. First, I think it would be good to have this in mind: there are two types of trim: 1. Aircraft pitching moment trim, which refers to making the aircraft pitching moment zero, and 2. stick force trim, which, obviously, refers to zeroing the pilot stick forces. As Heiko has already pointed, airliners and most business jets use the stabilizer for pitching moment trim. In JSBSim this CAN be modeled as follows: channel name=Pitch : : summer name=Stabilizer Trim Sum inputfcs/pitch-trim-cmd-norm/input !-- Note that here is the trim variable that comes from the trimming algorithm -- clipto min-1/min max 1/max /clipto /summer : : This will yield a fcs/stabilizer-trim-sum that can be mapped into a fcs/stabilizer-pos-deg (using an aerosurface_scale) which can be then used to calculate the tail angle of attack (alpha+stab-downwash) and from there the tail lift and/or pitching moment (of course this aerodynamic data is not always easy to achieve). Regarding the second type of trim (stick force), as far as I know JSBSim does not have the capability for this yet, although it may be possible to build that on the base of existing trimming options). For manually operated elevators, the elevator angle for zero force will depend on hinge moments (affected by alpha_tail, dynamic pressure, etc.), and will normally will be different from 0 degrees. For powered elevators (as in modern or high performance aircraft) zero elevator deflection will give zero stick force (by means of an artificial feeling system). For how all said above can be applied in FGFS...well, somebody familiar with that part would need to jump in. I hope this was not more confusing than helpful... Fabian On Sun, Mar 7, 2010 at 7:29 AM, Innis Cunningham inn...@hotmail.com wrote: Hi Guys I think you will find on all Boeing aircraft if the elevator is out of neutral for a set amount of time the horizontal stabilizer runs to return the elevator to the null position.Hence retriming the aircraft.Hence the name stabilizer trim I think also you will find that the tab on the elevator is not a trim tab but moves in the opposite direction to the elevator movement. So until we get a working FDM for the horizontal stabilizer in FG anything else will be a hack. Cheers Innis Hi, I just tried with the SenceaII and both Ti and elevator filter influence this. Great, thanks to all for the help! Cheers Heiko If you have a pid-simple-controller, try increasing Ti, it slows down the action. Hi Torsten, That sounds like it could be done without nasal just in the autopilot file. I guess the speed of the trim-pitch-channel can be changed with the filter? (The 737-300 has a speed-trim at certain situations) Kind regards Heiko Hi Heiko, the auto-pitch-trim channel moves the elevator trim to return the elevator into the neutral position while the pitch-channel moves the elevator to change attitude. Or a bit more technical: The auto-pitch-trim-channel compares the elevator-pos-norm to a reference of zero and adjusts elevator-trim The pitch-channel compares e.g. current pitch with a reference of some calculated target pitch and adjusts elevator-pos Usually the pitch-trim channel is much slower than the elevator channel. HTH, Torsten -- Download Intel® Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel __ Do You Yahoo!? Sie sind Spam leid? Yahoo! Mail verfügt über einen herausragenden Schutz gegen Massenmails. http://mail.yahoo.com -- Download Intel® Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net
[Flightgear-devel] dme
This writes the source frequency to dme/frequencies/selected-mhz to fix the
dme hold for the second source , and for an indication in the property tree
that it is doing what it's supposed to .
Cheers
Index: dme.cxx
===
RCS file: /var/cvs/FlightGear-0.9/source/src/Instrumentation/dme.cxx,v
retrieving revision 1.21
diff -U 3 -r1.21 dme.cxx
--- dme.cxx 4 Sep 2009 17:01:53 - 1.21
+++ dme.cxx 8 Mar 2010 00:32:22 -
@@ -96,7 +96,8 @@
if (frequency_mhz != _last_frequency_mhz) {
_time_before_search_sec = 0;
_last_frequency_mhz = frequency_mhz;
-}
+}
+_frequency_node-setDoubleValue(frequency_mhz);
// Get the aircraft position
double longitude_rad =
--
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[Flightgear-devel] dme fix
My first email seems to have vanished , so here goes again ...
I fixed the dme so that it writes the source frequency to
dme/frequencies/selected-mhz , which allows
dme hold to use source 2 (nav[1]) .
This was probably intended in the first place.
Cheers
Index: dme.cxx
===
RCS file: /var/cvs/FlightGear-0.9/source/src/Instrumentation/dme.cxx,v
retrieving revision 1.21
diff -U 3 -r1.21 dme.cxx
--- dme.cxx 4 Sep 2009 17:01:53 - 1.21
+++ dme.cxx 8 Mar 2010 00:32:22 -
@@ -96,7 +96,8 @@
if (frequency_mhz != _last_frequency_mhz) {
_time_before_search_sec = 0;
_last_frequency_mhz = frequency_mhz;
-}
+}
+_frequency_node-setDoubleValue(frequency_mhz);
// Get the aircraft position
double longitude_rad =
--
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Re: [Flightgear-devel] [Jsbsim-devel] Airliners and Auto Pitch-Trim
It should be possible to model trim tab effects on the stabilizer using function definitions in the aerodynamics section and in the system or flight_control section. The trim tab setting could be used to calculated the stabilizer pitching moment, and it should then be possible to calculated the equilibrium stabilizer position. The flight control components would be in charge of moving the aerosurface to that position. Subsequently, the lift and drag contributions would be calculated. I think that could work . Jon From: Leonardo Fabian Grodek [mailto:fabian.gro...@gmail.com] Hi, I have no experience in FGFS capabilities in terms of autopilot and trimming, but I do have some in JSBSim, so I will refer only to that FDM, and I hope this will be relevant to this discussion. First, I think it would be good to have this in mind: there are two types of trim: 1. Aircraft pitching moment trim, which refers to making the aircraft pitching moment zero, and 2. stick force trim, which, obviously, refers to zeroing the pilot stick forces. As Heiko has already pointed, airliners and most business jets use the stabilizer for pitching moment trim. In JSBSim this CAN be modeled as follows: channel name=Pitch : : summer name=Stabilizer Trim Sum inputfcs/pitch-trim-cmd-norm/input !-- Note that here is the trim variable that comes from the trimming algorithm -- clipto min-1/min max 1/max /clipto /summer : : This will yield a fcs/stabilizer-trim-sum that can be mapped into a fcs/stabilizer-pos-deg (using an aerosurface_scale) which can be then used to calculate the tail angle of attack (alpha+stab-downwash) and from there the tail lift and/or pitching moment (of course this aerodynamic data is not always easy to achieve). Regarding the second type of trim (stick force), as far as I know JSBSim does not have the capability for this yet, although it may be possible to build that on the base of existing trimming options). For manually operated elevators, the elevator angle for zero force will depend on hinge moments (affected by alpha_tail, dynamic pressure, etc.), and will normally will be different from 0 degrees. For powered elevators (as in modern or high performance aircraft) zero elevator deflection will give zero stick force (by means of an artificial feeling system). For how all said above can be applied in FGFS...well, somebody familiar with that part would need to jump in. I hope this was not more confusing than helpful... Fabian -- Download Intel#174; Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] Web Site
I like it too. On Sun, Mar 7, 2010 at 9:22 PM, Pete Morgan ac...@daffodil.uk.com wrote: Have developed the idea a bit further. http://fg-www.appspot.com/ idea is to have a dedicated aircraft and Online site also is this worth pursuing ? Its quite neat and developer friendly on the Google App Engine. pete Curtis Olson wrote: On Fri, Feb 12, 2010 at 9:06 PM, Pete Morgan ac...@daffodil.uk.com mailto:ac...@daffodil.uk.com wrote: I want to help please... Hi Pete, Here's one possible idea. Why not whip together a replacement front page and maybe a sample sub-page, put it in a temporary location, and we can take a look. That way we could present some different ideas and see if we like them, but at the same time, you don't have to do a huge amount of work only to find out that no one likes the new design proposal. Best regards, Curt. -- Curtis Olson: http://baron.flightgear.org/~curt/ http://baron.flightgear.org/%7Ecurt/ -- SOLARIS 10 is the OS for Data Centers - provides features such as DTrace, Predictive Self Healing and Award Winning ZFS. Get Solaris 10 NOW http://p.sf.net/sfu/solaris-dev2dev ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel -- Download Intel#174; Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel -- Download Intel#174; Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] Airliners and Auto Pitch-Trim
Hi Guys Another thing to keep in mind with the horizontal stabilizer is that on Boeing aircraft at least it is a reverse aerofoil so any lift is in a down direction. This is just for those that might not be aware of that. Cheers Innis _ Looking for a new home? With all the latest places, searching has never been easier. http://clk.atdmt.com/NMN/go/157631292/direct/01/-- Download Intel#174; Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
