Re: [Flightgear-users] a few questions about the f16
Bernhard Auzinger wrote: Hi everybody, when flying the f16 in a dive with full thrust, the elevator begins to bounce up and down at about 800 knots. But why? Is it the fly-by-wire system of the f16, which is holding the a/c in a stable flight attitude? Or is it a failure in the Model? It is the fly-by-wire logic that might need some more fine tuning, although it only happens in over-speed situations. So it might actually happen in real also ... I read about the f16, that it can reach Mach 2 in a straightforward flight. But how could I reach Mach 2? The maximum I reach is about 750 knots (~sonic speed). Did I get something wrong in this case? It can reach Mach 2.0 at 40,000 feet only. Our model does that as well. Erik ___ Flightgear-users mailing list Flightgear-users@flightgear.org http://mail.flightgear.org/mailman/listinfo/flightgear-users 2f585eeea02e2c79d7b1d8c4963bae2d
Re: [Flightgear-users] a few questions about the f16
On Sunday 26 June 2005 15:14, Erik Hofman wrote: Given 190 m/s = 623 ft/s http://www.grc.nasa.gov/WWW/K-12/Missions/Jim/Project1ans.htm So 190 m/s must be pretty close. According to this http://www.grc.nasa.gov/WWW/K-12/airplane/mach.html Mach calculator, the speed of sound at 40 000 feet is 660 mph. And acording to http://www.onlineconversion.com/speed_common.htm 660 mph is about 295 m/s. -- Roy Vegard Ovesen ___ Flightgear-users mailing list Flightgear-users@flightgear.org http://mail.flightgear.org/mailman/listinfo/flightgear-users 2f585eeea02e2c79d7b1d8c4963bae2d
Re: [Flightgear-users] a few questions about the f16
Well, you're on the right track, but 100 KIAS at sea level would behave pretty close to 100 KIAS at 40,000 feet. But 400 KIAS at sea level is sub-sonic, while at 40,000 feet it is transonic. So, it behaves differently. Don't ask me how differently, because I'm clueless about aerodynamics beyond the speed of sound.-NickOn Jun 26, 2005, at 13:59, Bernhard Auzinger wrote:Now, I think I got it right. The airspeed shown on the hud is not the true airspeed. It's the indicated airspeed. At high altitudes the IAS is much lower because of the lower air pressure etc. But aerodynamically 400 knots IAS at sea level and 400 knots IAS at 4 ft behave identical. ___ Flightgear-users mailing list Flightgear-users@flightgear.org http://mail.flightgear.org/mailman/listinfo/flightgear-users 2f585eeea02e2c79d7b1d8c4963bae2d
Re: [Flightgear-users] a few questions about the f16
An interesting but simple explanation can be found at http://www.grc.nasa.gov/WWW/K-12/airplane/sound.html There is also a MACH and speed of sound calculator there that you can download as a Java applet. At http://www.grc.nasa.gov/WWW/K-12/UndergradProgs/index.htm there are many such applets available including an airfoil sim and an engine sim. These sims are great for learning how it all works. I have to give credit to my 10 year old son for finding them though and correcting me on the changes in the speed of sound at high altitudes. Never too old to make a mistake! Chris Ridley [EMAIL PROTECTED] Well, you're on the right track, but 100 KIAS at sea level would behave pretty close to 100 KIAS at 40,000 feet. But 400 KIAS at sea level is sub-sonic, while at 40,000 feet it is transonic. So, it behaves differently. Don't ask me how differently, because I'm clueless about aerodynamics beyond the speed of sound. -Nick On Jun 26, 2005, at 13:59, Bernhard Auzinger wrote: Now, I think I got it right. The airspeed shown on the hud is not the true airspeed. It's the indicated airspeed. At high altitudes the IAS is much lower because of the lower air pressure etc. But aerodynamically 400 knots IAS at sea level and 400 knots IAS at 4 ft behave identical. ___ Flightgear-users mailing list Flightgear-users@flightgear.org http://mail.flightgear.org/mailman/listinfo/flightgear-users 2f585eeea02e2c79d7b1d8c4963bae2d ___ Flightgear-users mailing list Flightgear-users@flightgear.org http://mail.flightgear.org/mailman/listinfo/flightgear-users 2f585eeea02e2c79d7b1d8c4963bae2d
RE: [Flightgear-users] A few questions
Kristin I have the 0.9.8a windows version working 50% stable on my PC. I have even been able to find Lampson field 1O2 in Lake County CA! However there are several errors showing up on the FGFS dos window. For instance I am flying from Sonoma Valley 0Q3 with aircraft pa28-161 and I get the following message. Failed to find runway 28R at airport 0Q3 WARNING: Legacy engine definition in YASim configuration file. Please fix. Sonoma has runway # 07x, 17x, 25, 35 I left the runway on default. Do I need to specify the runway? You don't have to. Use --runway= if you want How do I fix the YASim engine problem? You don't: it's down to the aircraft developer for that particular model If I select location/position in air and specify Lampson 1o2 I get this error. Unknown runway code 07x passed to GetReverseRunwayNo(...) Failed to find runway 07x at airport 0Q3 WARNING: Legacy engine definition in YASim configuration file. Please fix. Failed to find runway 28 at airport 1o2 Failed to find a good runway for 1o2 WARNING: Legacy engine definition in YASim configur I also have seen something about stability % once or twice and the aircraft was not managable at all. I don't know how this works under Unix but in the flightgear wizard there is an advanced button and I am also unable to modify any of the parameters under the General heading. For instance it shows the airport, aircraft and runway but I cannot enter another airport etc... Is there a file I need to edit to change the default startup values? I would like to fly out of Lakport CA Lampson field as I know the area pretty well now I have been here 6 years. It's kind of a pain to keep having to position back to 1O2/Lampson everytime I start the program. There is, (system.fgfsrc), but that's not easy for beginners: fgrun will do everything you need. Another weird thing was I saw something in the FGFS dos window about missing scenery like tall buildings/skyscrapers, HA we don't even have 10 foot of railroad track in this county let alone skyscrapers. I didn't know there was anywhere in the US that didn't have a few rail lines but Lake county has none. I came from New Jersey and there were rail lines everywhere. Use --disable-random-objects. Anyone know what 10 degree segment has north New Jersey on it? I could download that instead as I am also familiar with most of NJ from NY border to about Trenton east to west. No - use the graphical scenery download interface. I am looking to learn some basics of flying, perhaps getting a student permit a year or so from now and would really like to get FG working with a good set of data that is in an area I know from the ground. FGFS is a good route to go down. Try using the Hunter first off - that's probably the easiest to fly, if your hardware is up to it. Otherwise use the default aircraft. But you'll have to get used to the prop effects. Basically you have a working 0.9.8a system, so far as I can see. Ignore the warnings and learn to fly. Regards, Vivian ___ Flightgear-users mailing list Flightgear-users@flightgear.org http://mail.flightgear.org/mailman/listinfo/flightgear-users 2f585eeea02e2c79d7b1d8c4963bae2d
