Re: [Flightgear-devel] B-47 airfoil
Thomas Putnam wrote: > At this point you just have the tip of the iceberg for what you really > want. A fair piece of work remains before you have what what you think > you have. Alternatives would be to look for airframe aero data at the > NACA/NASA web site for the B-47 or to know how to interpret curves and > charts in the pilots manual. Again, I have done things like this before. > In the mean time ... Unfortunately, I have not found much data at NTRS. I am not sure if I am making the right searches though. I will have to learn more about interpreting the graphs in the POH, as there are plenty of them. > - You have the parasite drag for the wing. There is a well established > methodology to go from one to the other. You still need something like > Horner's "Fluid Dynamic Drag" to get the drag for the rest of the > airframe and you still need to get induced drag as well. Again, > simplified methods give induced drag. Luckily, JSBSim allows coefficient buildup, so I can treat the fuselage, stabs, wings and nacelles separately. However, it may be better to put it all into DATCOM+ and get one single set of coefficients. > - Pitching moment data is for the bare airfoil you need to do some > transformations and math to get the data for the complete airframe. By > the way, the airfoil used for the horizontal stab is critical in terms > of how your plane will fly. Do you have that data too ? If not, start > thinking about how you might get it. I have a pretty accurate drawing of the ac, but not enough to figure out anything more than the thickness. It appears to be about 8%. I was going to assume that it is a NACA 0009, as well as the horizontal stab. > Look for the "DATCOM" software. It is a little difficult to use, but it > should give you everything you are looking for and need right now. Yes, > I have used it too. Already have it, and some examples to learn from. Josh Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] Chinook Was: Re: Helicopter: First Impressions
On Wed, 28 Jun 2006, chris wrote: That is backward. Indeed so. ;) (already sorted out) The chinook used to have just an "Stability Augmentation System" the SAS for short. You still did not want to take your hands off the cyclic but it made it somewhat smoother. Yea I read a little about it. The AFCS with underlying systems is perhaps more like something between an SAS and an autopilot. From CH47 Theory of operations: The advanced flight control system provides the following modification and additions to the stability augmentation system (SAS) installed in earlier model CH-47 helicopters. 1. Continuous pitch attitude and, in the long term, airspeed hold referenced to the longitudinal control position throughout the flight envelope. 2. Long term bank angle and heading hold in level flight and bank angle hold about any stabilized bank angle in turning flight. 3. A stable longitudinal positive control gradient from maximum rearward to maximum forward flight speeds. 4. Vernier beep trim of bank angle and airspeed. 5. Radar and barometric altitude hold. 6. Coupled heading selected through the HSI bug error. 7. Cockpit control position transducers (control switch pick-offs) in the longitudinal, lateral, and directional control system to improve maneuverability. 8. The mechanical detent switches on the lateral and directional controls have been replaced by electronic signals derived from control position signals supplied to the AFCS. 9. Automatic longitudinal cyclic trim positioning to the ground mode when either aft wheels are on the ground. Point (1) ought to make the aircraft appear rather differently to the pilot than the older models with only SAS did. (3) I trim manually for now. (hopeless to fly it straight if this is not trimmed correctly to speed and thrust) I suspect (4) together with (5) is used a lot during normal free flight cruise. (when not flying AP alltogether) Apparently the SAS also included the LCT (automatic? -- just not auto ground mode?). I got it significantly more stable now. (without cheating with faked hstabs and vstabs) At one point, when I used a silly power configuration, it even flew fairly straight up to 470 kias. ;) (never mind the G meter) But I still can't figure out how to make it cruise with the right pitch. No matter how I adjust the parameters, it flies nose-up about 7° at cruise (constant speed, heading and altitude). Mystery...Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] Chinook Was: Re: Helicopter: First Impressions
On Wednesday 28 June 2006 02:37, Joacim Persson wrote: > On Tue, 27 Jun 2006, Maik Justus wrote: > > I'm working now on simulating the rotor on several points along the > > rotor blades (with twist). > > I suspect that twist to vary with load. The twist should not vary with load, but the coning angle will. > It's the tips that has a 12° higher > incidence (sic!) than the root, when the rotor is stopped that is. That is backward. The tip has washout ie it has a lower angle of attack than the root. The idea is to achieve an even distribution of lift. The reason is that the velocity at the root of the blade in the plane of rotation is much less than at the tip. If you had made the tips have a higher AOA then all the lift would be concentrated there and either the blades would break or cone so bad it would not be able to take off. > I guess > that's a pre-tensioning of the blade; that the lift moment on the blade (it > has some naca profile if I remember it right) will twist it back to a more > straight shape under load or perhaps even twist it the other way. The older chinook had a modified naca0012 like most helis. That is a fully symmetrical shape and therefore there is "theoretically" no moment about the blades long axix. > > I have begun to develop some doubts if this reductionistic approach is the > way to go for simulating an aircraft that under normal operation is flown > with an electronic flight control system which does it best at making the > aircraft behave like a much smoother thing to fly than it is with the FCS > broken. What we want to simulate in the end is certain movements of the > aircraft following a certain input, not necessarily all the gory details in > between that the pilot (normally) never have to worry about. > > But then again -- where's the fun in simplicity? ;) The chinook used to have just an "Stability Augmentation System" the SAS for short. You still did not want to take your hands off the cyclic but it made it somewhat smoother. Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] FlightGear packages for SuSE Linux
On Thursday 29 June 2006 15:31, Ladislav Michnovič wrote: Thank you for your effort on this - I will download the i586 packages and report back. > Hello. > Thanks to the openSuSE Build service, I builded rpm packages of FG > for Suse Linux 10.x which are available at > http://software.opensuse.org/download/home:/lmich/SUSE_Linux_10.1/i586/Flig >htGear-0.9.10-17.1.i586.rpm respectively > > http://software.opensuse.org/download/home:/lmich/SUSE_Linux_10.1/x86_64/Fl >ightGear-0.9.10-17.1.x86_64.rpm > http://software.opensuse.org/download/home:/lmich/SUSE_Linux_10.1/noarch/Fl >ightGear-data-0.9.10-2.1.noarch.rpm or > http://software.opensuse.org/download/home:/lmich/SUSE_Linux_10.0/i586/Flig >htGear-0.9.10-17.1.i586.rpm respectively > http://software.opensuse.org/download/home:/lmich/SUSE_Linux_10.0/x86_64/Fl >ightGear-0.9.10-17.1.x86_64.rpm > http://software.opensuse.org/download/home:/lmich/SUSE_Linux_10.0/noarch/Fl >ightGear-data-0.9.10-2.1.noarch.rpm > > The build number can increase, so if the link is unavailable, please > search manualy in http://software.opensuse.org/download/home:/lmich/ > You need noarch package FlightGear-data to be installed first. I would > appreciate any feedback. > Regards Ladislav. > > Using Tomcat but need to do more? Need to support web services, security? > Get stuff done quickly with pre-integrated technology to make your job > easier Download IBM WebSphere Application Server v.1.0.1 based on Apache > Geronimo > http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 > ___ > Flightgear-devel mailing list > Flightgear-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/flightgear-devel -- All the best Willie Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] FlightGear packages for SuSE Linux
Hi Ladislav, Is there an easier "top level" link I can point to from the FlightGear web site? I don't think I would be very successful at maintaining 6 links that will continue to change each time you do a new build. Thanks, Curt. Ladislav Michnovic( wrote: > Hello. > Thanks to the openSuSE Build service, I builded rpm packages of FG > for Suse Linux 10.x which are available at > http://software.opensuse.org/download/home:/lmich/SUSE_Linux_10.1/i586/FlightGear-0.9.10-17.1.i586.rpm > respectively > > http://software.opensuse.org/download/home:/lmich/SUSE_Linux_10.1/x86_64/FlightGear-0.9.10-17.1.x86_64.rpm > http://software.opensuse.org/download/home:/lmich/SUSE_Linux_10.1/noarch/FlightGear-data-0.9.10-2.1.noarch.rpm > or > http://software.opensuse.org/download/home:/lmich/SUSE_Linux_10.0/i586/FlightGear-0.9.10-17.1.i586.rpm > respectively > http://software.opensuse.org/download/home:/lmich/SUSE_Linux_10.0/x86_64/FlightGear-0.9.10-17.1.x86_64.rpm > http://software.opensuse.org/download/home:/lmich/SUSE_Linux_10.0/noarch/FlightGear-data-0.9.10-2.1.noarch.rpm > > The build number can increase, so if the link is unavailable, please > search manualy in http://software.opensuse.org/download/home:/lmich/ > You need noarch package FlightGear-data to be installed first. I would > appreciate any feedback. > Regards Ladislav. > > Using Tomcat but need to do more? Need to support web services, security? > Get stuff done quickly with pre-integrated technology to make your job easier > Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo > http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 > ___ > Flightgear-devel mailing list > Flightgear-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/flightgear-devel > -- Curtis Olsonhttp://www.flightgear.org/~curt HumanFIRST Program http://www.humanfirst.umn.edu/ FlightGear Project http://www.flightgear.org Unique text:2f585eeea02e2c79d7b1d8c4963bae2d Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
[Flightgear-devel] FlightGear packages for SuSE Linux
Hello. Thanks to the openSuSE Build service, I builded rpm packages of FG for Suse Linux 10.x which are available at http://software.opensuse.org/download/home:/lmich/SUSE_Linux_10.1/i586/FlightGear-0.9.10-17.1.i586.rpm respectively http://software.opensuse.org/download/home:/lmich/SUSE_Linux_10.1/x86_64/FlightGear-0.9.10-17.1.x86_64.rpm http://software.opensuse.org/download/home:/lmich/SUSE_Linux_10.1/noarch/FlightGear-data-0.9.10-2.1.noarch.rpm or http://software.opensuse.org/download/home:/lmich/SUSE_Linux_10.0/i586/FlightGear-0.9.10-17.1.i586.rpm respectively http://software.opensuse.org/download/home:/lmich/SUSE_Linux_10.0/x86_64/FlightGear-0.9.10-17.1.x86_64.rpm http://software.opensuse.org/download/home:/lmich/SUSE_Linux_10.0/noarch/FlightGear-data-0.9.10-2.1.noarch.rpm The build number can increase, so if the link is unavailable, please search manualy in http://software.opensuse.org/download/home:/lmich/ You need noarch package FlightGear-data to be installed first. I would appreciate any feedback. Regards Ladislav. Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
