Re: [Flightgear-devel] newer stuff
The quote that comes to mind goes something like Sure the Mustang can't do what the Spitfire does, but doesn't do it over Berlin. Spitfires, like the Me's and Fw's lacked range because they were conceived of as tactical, not strategic, aircraft. They did their job very well, being more maneuverable that the Mustang, but all had difficulties operating cross channel, much less at the longer ranges required to escort bombers into Germany, even with drop tanks. Some British pilots, after seeing the Mustangs, asked about changes in the Spitfire to achieve comparable range only to be told that the structural changes needed just weren't feasible. Regards, Charlie Jim Wilson wrote: Lee Elliott [EMAIL PROTECTED] said: I thought one of the major features of the p51 was it's range. I think it was one of the few, if not the only fighter that had the range and endurance for bomber escort duties from the UK into Germany. I believe that the German a/c were generally of lower range and were more likely to be flown from captured airfields nearer the battle front for the attack role. Fighters based in Germany would be there primarily for defence against attacks and so didn't need great range. That's right AFAIK. They added drop tanks to really extend the range. Of course there were the Spitfires, which I think must have flown missions into Germany. Pretty much all the fighters were involved in either bomber escorts or enemy bombing mission intercepts. That's about all fighters are good for. It was just the Japanese that decided they could be used as bombs as well. Best, Jim ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
Re: [Flightgear-devel] [OT] BA-609, V-22 derivative aircraft
Martin Spott wrote: Martin Spott wrote: ... Oh, you get heavily increased torque from the ailerons for manouverability and you get much more lift from large wings at low speed - especially because on the current design at least 90 % of the wing area suffers from the down-wind generated by the two the rotors, Ah yes, prop wash helps improve control effectivity at low speeds. It isn't going to be great, but should help. So how smooth is it when lift become significant on the wings? The wash off the rotors should be strong, but very turbulent. Air flow around the wings ought to be one very nasty numerical analysis problem, especially near wing stall. I can only imagine what surprises it held for the designers. Regards, Charlie H. -- You're not drunk if you can lie on the floor without holding on. ---Dean Martin ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
Re: [Flightgear-devel] [OT] BA-609, V-22 derivative aircraft
Martin Spott wrote: The big problematic area ... regime is unstable and recovery difficult. This does not have to be as difficult as it is with the V-22. The Osprey is designed for being stuffed into _very_ small space below a ship's deck. If they had more space then it would have been possible to improve security simply by increasing the wing span, The problem, I think, is not in the wing span. In transition the aircraft is working around the stall speed for the wings. I would think that a larger wing would decrease rather than increase stability, no? Regards, Charlie H. -- C makes it easy to shoot yourself in the foot; C++ makes it harder, but when you do, it blows away your whole leg. - Bjarne Stroustrup ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
Re: [Flightgear-devel] [OT] BA-609, V-22 derivative aircraft
Curtis L. Olson wrote: Tony Peden writes: --- Jim Wilson [EMAIL PROTECTED] wrote: Hmmmthat should thin the ranks down on Wall St even more. ... IMHO that thing even looks dangerous :-) More dangerous than a helicopter? ... It sounds like avoiding the vortex ring state... I think the big danger is at landing or takeoff. ... The big problematic area for this class of aircraft historically has been the transition between hover, or rotor based operation and flying, where the wings are important. That regime is unstable and recovery difficult. Regards, Charlie H. -- C makes it easy to shoot yourself in the foot; C++ makes it harder, but when you do, it blows away your whole leg. - Bjarne Stroustrup ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
Re: [Flightgear-devel] PA-28-161 C-FBJO
I've flown several times as a passenger in that particular model. Loved it. I'm in deep envy and insist on being in your will. ;-) Regards, Charlie H. David Megginson wrote: After a few months of dithering, ... did a test flight and had my AME do a detailed prepurchase yesterday. Regards, Charlie H. -- C makes it easy to shoot yourself in the foot; C++ makes it harder, but when you do, it blows away your whole leg. - Bjarne Stroustrup ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
Re: [Flightgear-devel] ..anyone else seen this?: https://sourceforge.net/ down
Worked for me yesterday and just now. A puzzlement. Charlie H. Arnt Karlsen wrote: ..anyone else seen this?: https://sourceforge.net/ down ..reads:We're Sorry. The SF.net domain is temporarily pointing at this maintenance page. Please access the SourceForge.net site at https://sourceforge.net -- you will be redirected there in 10 seconds. ..well, I did yesterday this time too. -- C makes it easy to shoot yourself in the foot; C++ makes it harder, but when you do, it blows away your whole leg. - Bjarne Stroustrup ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
Re: [Flightgear-devel] Fokker Dr.1 model added
I read somewhere that the aircraft was very sensitive to cross winds and would weather vane on the mearest whisper of such. Regards, Charlie H. Michael Selig wrote: I have just added the Fokker Dr.1 triplane to the CVS. There are notes in the readme below about how to get a 3D model file. Unfortunately, I could not acquire one under the GNU GPL. If I were going to be in a dog fight and had my pick of the Camel or Dr.1, the Dr.1 would be the weapon of choice. The Red Baron once said it It climbed like a monkey and maneuvered like the devil. I concur. Regards, Michael pre == = Fokker Dr.1= = WWI Fighter= = for FlightGear with LaRCsim and the UIUC Aeromodel = == = Flight model by: = = Michael Selig, et al. ([EMAIL PROTECTED]) = = http://www.aae.uiuc.edu/m-selig/apasim.html= == To run, try: fgfs --aircraft=fkdr1-v1-nl-uiuc Files and directory structure required in $FG_ROOT/Aircraft/ to fly the model: fkdr1-v1-nl-uiuc-set.xml fkdr1/Sounds/uiuc/fkdr1-sound.xml UIUC/fkdr1-v1-nl/aircraft.dat UIUC/fkdr1-v1-nl/CDfa-03.dat UIUC/fkdr1-v1-nl/CLfa-03.dat UIUC/fkdr1-v1-nl/Cmfa-03.dat UIUC/fkdr1-v1-nl/Cmfade-01.dat These files above come with the FlightGear base package. To add a 3D external model, read the file: ~/Aircraft/UIUC/beech99/README.beech99.html as an example to follow. A Fokker Dr.1 model file that does work is fokdr1m2.zip from http://www.flightsim.com. (The fuselage for this model is too wide in the cockpit region.) There are several variants of this which can also be used, namely these files: dr-1cfs.zip dr1mp98.zip dr1mpcfs.zip fkdr1blk.zip fokdr-15.zip ~~ Model description and updates: 11/10/2002 - First release: v1-nl * Motivation: FGFS and the UIUC aero model were used to develop flight models for both the Sopwith Camel and Fokker Dr.1 Triplane. These models were then used in another simulation with a collaborator, Brian Fuesz. In that simulation, guns, terrain, villages, multiple planes, etc were added to simulate the last flight of the Red Baron. This work was filmed for the Discovery Channel show Unsolved History: The Death of the Red Baron scheduled to first air Dec 18, 2002. * A weights and balance was performed to arrive at an allowable c.g. location and from that data, mass moments of inertia were calculated. * Lift, drag and pitching moment data is modeled from -90 to +90 deg. Because the aerodynamics are not modeled from -180 to +180 deg, the aircraft will sometimes twitch when coming out of a tail slide as it passed through 90 deg. * In general, the aerodynamics are modeled using various sources. * Apparent mass effects are modeled. * Gyroscopic forces caused by engine rotation and aircraft rotations are modeled. For an animation of how a WWI-type rotary engine works, go here:http://www.keveney.com/gnome.html An example of gyroscopic forces, are those forces produced when one tries to rotate by hand a spinning bicycle wheel. * Spin aerodynamics are not yet modeled. * The simulation starts on the ground. Throttle up to take off or alternatively, use Ctrl-U to jump up in 1000-ft increments. * The Fokker Dr.1 did not have brakes. Application of brakes in FGFS will cause the aircraft to promptly nose over. (I have added a fake contact point ahead of the aircraft to avoid completely tipping over.) The c.g. of the aircraft sits almost directly above the wheel contact point. There is a reason for this. The aft fuselage and tail were designed to be very light. Thus, the tail could not support much load, so the weight of the aircraft largely rests on the main wheels, which again requires the c.g. to be almost directly above the wheels. * WWI aircraft engines did not have a conventional throttle (at least most did not). The engines were either on or off/idle using a blip-throttle. So it is not realistic to fly with a variable throttle, which the current model allows. * To modelers, I can provide a graphic showing the c.g. location. * Something I have not yet modeled is rudder ineffectiveness on roll out and touch down. When the aircraft is sitting on the wheels and tail skid, the angle of attack of the wing is so high that it is mostly stalled and the flow off the aft fuselage is also not well behaved. The result is that there is not much dynamic pressure (flow speed) on the vertical stabilizer, so there is little rudder authority in this condition. As a point of interest, why would the designers settle for this result? It's because of the rotary engine. The max speed is limited to 1200 rpm because of the
Re: [Flightgear-devel] 3D HUD
Norman Vine wrote: Hi All I have placed a tarball of hud... I am working on a major restructuring of the HUD to make having multiple versions of both the 2D and 3D HUDs available at the same time Good. When I worked on the code I expected that is would eventually be expanded to support both 2D and 3D versions, with both dynamically and independently reconfigurable at run time, such as when different aircraft were selected or some optional piece of information readout was toggled on or off. Regards, Charlie H. -- C makes it easy to shoot yourself in the foot; C++ makes it harder, but when you do, it blows away your whole leg. - Bjarne Stroustrup ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
[Flightgear-devel] OT: re - Jim Wilson's Employer
Jim Wilson wrote: ... I'll see if I can do that over the next few days. Time is limited these days. The company I work at does 80% of their business this month and next (see http://www.kelcomaine.com to find out why). ... From a couple of the pictures there I assume the during the off season your crew works on battle bots? Charlie H. -- Last week I stated this woman was the ugliest woman I had ever seen. I have since been visited by her sister and now wish to withdraw that statement. - Mark Twain ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
Re: [Flightgear-devel] New FGFS merchandise
John Check wrote: On Tuesday 02 July 2002 7:39 am, Martin Spott wrote: FYI, there are a lot of new FGFS logo items available. http://www.cafepress.com/cp/store/store.aspx?storeid=fgfs_gear The mugs look nice but I have to notice that the colour on the FlightGear Logo Mug starts disappearing after only a few months use utilizing a dishwasher, Martin. Ah. I was wondering about that. They've since improved the process but I don't have any idea how it worked out IRL. All the glass mugs that have colored paint/ink that I've come across include notices not to put them in the dish washer. Color fast paints able to stand up to dishwasher temps and alkalinity and that bond to glass are hard to come by cheap. If the mug is of value to you I would hand wash and use only warm water for wash and rinse. Regards, Charlie H. -- C makes it easy to shoot yourself in the foot; C++ makes it harder, but when you do, it blows away your whole leg. - Bjarne Stroustrup ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
Re: [Flightgear-devel] blue angel
Jon S Berndt wrote: ... Typically, the closer the CG is to the aerodynamic center, the quicker and easier you can yank the plane around (and possibly break your neck). It wouldn't surprise me that the A-4 is so maneuverable. It would be nice to get input from a real A-4 driver or find some old aero test data Nimble. Hmm. Wasn't the F16 so responsive that it became the first fighter to put its pilot to sleep if he yanked to hard on the controls. I recall a video made during research after an unexpected crash. The g force load up is supposedly so much faster than the F4 that experienced F4 pilots in the F16 pulled right past the tunnel vision point to blackout before realizing what was happening. Anyone else remember this with details? Also, A means attack, not fighter. The A4 was Douglas' hot rod nuke bomber. Its primary design goal was delivering a largish H-bomb using an interesting attack sequence. Alternately it had hard points for fuel tanks, bombs and missiles for conventional ground attack. Dog fighting was contemplated, but more in terms of self defense as it was strictly sub-sonic. Regards, Charlie H. -- C makes it easy to shoot yourself in the foot; C++ makes it harder, but when you do, it blows away your whole leg. - Bjarne Stroustrup ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
Re: [Flightgear-devel] Re: Patch for options.cxx
Curtis L. Olson wrote: ... patch moves all the command line help text to an xml file and then loads it at run time, rather than having the text hard coded into the source. Sound like a good idea? Any objections?... It is an obvious and long needed improvement. However, if I read the code correctly, it seems to throw an exception if it cannot find the xml help file. If the file isn't needed because an error wasn't made, does the program abort because it cannot find the file? Admittedly I'm being lazy in not testing this myself. Regards, Charlie H.. -- C makes it easy to shoot yourself in the foot; C++ makes it harder, but when you do, it blows away your whole leg. - Bjarne Stroustrup ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
Re: [Flightgear-devel] Re: Patch for options.cxx
Erik Hofman wrote: C. Hotchkiss wrote: ... If the file isn't needed because an error wasn't made, does the program abort because it cannot find the file? Admittedly I'm being lazy in not testing this myself. It only throws an exception when --help (or an incorrect argument) was specified or *and* the file options.xml doesn't exsist. So, does the program abort or advise and go on? I'm thinking that the exception event would be rare, but even so, a miss installation or an accidentally deleted file shouldn't leave the user scratching his or her head. When easily done, good hints about why things went wrong should be given. Regards, Charlie H. -- C makes it easy to shoot yourself in the foot; C++ makes it harder, but when you do, it blows away your whole leg. - Bjarne Stroustrup ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
[Flightgear-devel] Off topic?
This was forwarded to me by my mother-in-law. I checked back to SI to see if they were the attributed source and found a link to a movie on the subject as well. Why the original author chose to submit to SI, I don't know. Regards, Charlie H. http://rense.com/general8/boom.htm http://www.gpsinformation.net/exe/boom.html -- C makes it easy to shoot yourself in the foot; C++ makes it harder, but when you do, it blows away your whole leg. - Bjarne Stroustrup ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
Re: [Flightgear-devel] Aircraft
Arnt Karlsen wrote: On Sun, 02 Jun 2002 19:15:32 -0400, John Check [EMAIL PROTECTED] wrote in message [EMAIL PROTECTED]: On Sunday 02 June 2002 5:16 pm, Gene Buckle wrote: ..also, how about a _generic_ Mooney Bonanza? About 300 of Mooney didn't build the Bonanza, Beechcraft did. I have to admit though, a huge formation of forked-tail doctor killers would be a cool thing to see. :) forked-tail doctor killers That's a good one. .. ;-) ..I'm abit confused; these Bonanza's? range in size from 1 seat upwards, Mooney Mite? Could it be Beechcraft took over Mooney? Don't think so. No mention in news reports that I have seen mention Beechcraft. They have had a very interesting history that doesn't appear on their web site: 1929: (Albert Arthur) Mooney Aircraft Corp, Bridgeport Machine Co, 600 E 35 St, Wichita KS. 1946: Mooney Aircraft Inc, Kerrville TX. 1947: Mooney Aircraft Corp. 1955: Mooney Bros quit their interest to go with Lockheed design dept, but name continued with acquired rights. 1965: Mooney-Mitsubishi Aircraft Inc. 1967: Acquired production rights to Ercoupe from Alon Aircraft Co. Early 1969: Bankruptcy and sale to American Electronics Labs, with no production. Late 1969: Acquired by Butler Aviation, who ended operations in June 1971 with no aircraft production. 1970: Renamed Aerostar Aircraft Corp. 1974: Mooney Aircraft Div, Republic Steel Corp, acquisition of rights and tooling. Resumed production Jan 1, 1975. 1978: Mooney Mite Aircraft Corp (kits and plans only), Charlottesville VA. 1984: Merged with French distribution firm (Alexander Couvelaire). July 2001: Bankrupcy filed. Mar 2002: Acquired by AASI as Mooney Aircraft Co Inc div of Mooney Aerospace Group Ltd. No mention of Beech anywhere. Regards, Charlie H. -- C makes it easy to shoot yourself in the foot; C++ makes it harder, but when you do, it blows away your whole leg. - Bjarne Stroustrup ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
Re: [Flightgear-devel] DC-3 ground handling. Fixed?
Andy Ross wrote: [I combined a bunch of responses... Once the tailwheel leaves the ground, it's squirrely but controllable. This is not doubt bad form, but I found that holding the stick back to keep the wheel firmly on the ground during the takeoff roll until the aircraft took off on its own was the safest way to take off. Andy, Perhaps I'm showing some ignorance here (I'm certainly not a pilot, much less an expert), but isn't the induced drag in that situation so large as to preclude reaching flying speed? The wings acting at that angle much like a drag brake? I read somewhere that pilots deliberately pushed forward on the column to lift the tail at a specific speed in order to reduce drag and allow speed to build up. Regards, Charlie H. - C makes it easy to shoot yourself in the foot; C++ makes it harder, but when you do, it blows away your whole leg. - Bjarne Stroustrup ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
Re: [Flightgear-devel] DC-3 ground handling. Fixed?
Andy, I'm really just exploring near stall modeling issues so that our simulation can be improved. Anyway you can get a bird in the air is reasonable, especially if it shows up weaknesses in modeling. So, just for discussion's sake and noting that nobody with detailed knowledge of and experience with this aircraft has weighed in, I have questions. Isn't the L/D ratio at high angles of attack different (poorer) when in ground effect? If you can accelerate to above stall speed rolling on all three wheels, what happens when you start to lift. Wouldn't you expect the aircraft tend to nose up into stall? Regards, Charlie H. Cameron Moore wrote: * [EMAIL PROTECTED] (David Megginson) [2002.05.23 13:59]: Andy Ross writes: The tech drawings at http://www.douglasdc3.com/dc3tec/dc3tec.htm (especially the big one at the bottom) suggest to me an angle of incidence of 2-3 degrees, but I haven't printed them out and measured. As far as measuring aircraft dimensions and such, I use Gimp's measuring tool to measure things. Measure a known distance and record the length in pixels, then you can measure whatever else you want and do the pixel to feet conversions without haven't to print anything out. Pythagoras is your friend. :-) -- Cameron Moore [ Why is the man who invests all your money called a broker? ] ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel -- C makes it easy to shoot yourself in the foot; C++ makes it harder, but when you do, it blows away your whole leg. - Bjarne Stroustrup ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
[Flightgear-devel] Re:FGFS easter egg
Actually, what we have had was not an Easter egg, but a surprise improvement that might someday be the norm. Program Easter eggs are supposed to be hidden and activated by an arcane sequence of operator inputs. So, what should we consider adding into the program to be our first official egg, a parody on the Ever-ready Bunny? (The project keeps going and going and ... and never stops.) Regards, Charlie H. -- C makes it easy to shoot yourself in the foot; C++ makes it harder, but when you do, it blows away your whole leg. - Bjarne Stroustrup ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
Re: [Flightgear-devel] uncool easter egg
Alex Perry wrote: I definitely agree. It's a violation of almost every netiquette rule, that is concerned to virus-like behaviour or bandwith respect of others. I disagree. Almost _every_ new Microsoft-based program checks its home website, sometimes for logging and sometimes anonymous as in this case. It is really interesting to use a linux firewall for a modern MS system. I'm surprised there hasn't been a howl set up with that bit of MS spying. They've been skewered before for applications that install with covert net activity as the default. Are you referring to them going beyond the log in to active an application nonsense? Regards, Charlie H. -- C makes it easy to shoot yourself in the foot; C++ makes it harder, but when you do, it blows away your whole leg. - Bjarne Stroustrup ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
Re: [Flightgear-devel] Environment subsystem status
David Megginson wrote: C. Hotchkiss writes: The only place... Maybe somebody can recall these instances with better accuracy. Either way, history condemned us to English units. Yes, ditto for the Gimli Glider, the Air Canada 767 that ran out of fuel at altitude and was brought down safely on a drag strip (former runway) in Gimli, Manitoba: Ah, yes. I recall that now. A very interesting incident. Amusing that a low tech solution like dip sticks is still being used. Also instructive to efforts to convert the aircraft industry over to SI. It should be done, but with great care. Regards, Charlie H. C makes it easy to shoot yourself in the foot; C++ makes it harder, but when you do, it blows away your whole leg. - Bjarne Stroustrup ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
Re: [Flightgear-devel] Re: Environment subsystem status
Andy Ross wrote: Christian Mayer wrote: (Note: degrees are still valid as they are *internationally* well known. slugs aren't) Actually, there's a very good reason why we use a 360 degree circle. This number has loads of small integer divisors. ...In the days before calculators, this was really important. This same logic is why we have 60 minutes per hour and 24 hours per day. IIRC, 360 degrees is Babylonian in origin. For some reason multiples of 12 and the number 360 was very important to them. The multiple integer relationships not being a bad thought about why. Twelve also shows up strongly as an important number not only for them, but, for those familiar with the Bible, the ancient Hebrews as well - possibly by association. For example, in Jewish numerology, 3 stands for God, 4 for Heaven and 12 (3 x 4) for God in Heaven. (Don't ask why - I haven't a clue.) Imperial units also have an interesting relationship to some of the units used by the Egyptians. They used a foot of very close to 300 mm (11.8 inches) and the cubit of 450 mm (17.7 inches). The Romans, for some reason changed the latter to 16. Lacking an easy to define base standard, the problem of uniform measurements was never solved until long after the French gave us the metric system based upon latitude. Finally, (under Napoleon ?) the French tried to reform the calendar and make that metric or logical as well. Even with the Committee for Public Safety available to enforce it, they couldn't get that system to catch on. Never underestimate the power of tradition. Regards, Charlie H. -- C makes it easy to shoot yourself in the foot; C++ makes it harder, but when you do, it blows away your whole leg. - Bjarne Stroustrup ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
Re: [Flightgear-devel] Environment subsystem status
... If a FDM wants to use obscure units internally (e.g. because the developers are use to them) that's their choice. But when we have very universal data that a lot of people need (users, panel programmers, ...) we should use an international standard. I agree with the principle, but note that the aircraft panel instruments give the altitude in feet, not meters, the altimeter will be calibrated for inches of mercury, not pascals, and the airspeed will be in knots (or possibly statute mph), not kph -- using SI internally will force a lot of conversions. I'm sure that there exist SI aircraft panels somewhere, but I have not yet seen photos of any in general aviation. David, The only place that I know of that manufactures aircraft (or at least did routinely) with SI based instrumentation was the old Soviet Union. Some of their aircraft either sold to customers, or operating outside the SU were involved in at least two mid air collisions (IIRC, between heavies in India and off western Africa). This was thought at the time to be due to confusion over unit conversion, either in the cockpit or by the ATCs involved. Maybe somebody can recall these instances with better accuracy. Either way, history condemned us to English units. At any rate, might we introduce a configuration line in the set up files that alerts the program that all following units are SI instead of English? Ditto access members that are known to report/set data members/parameters in SI instead of English unit values? This might make dealing with airframes like some of the older Russian designs a bit easier and less error prone. Regards, Charlie H. -- Madam, there's no such thing as a tough child- if you parboil them first for seven hours, they always come out tender. - W.C. [William Claude] Fields (1879 - 1946) ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
Re: ..why C++ and not C?, was: [Flightgear-devel] View Oddity Between MagicCarpet and JSBSim
Flight Gear was originally written in C. I was one of those who urged adoption of C++ to take advantage of the features that the language offered, including the STL (standard template library.) Since then the various contributors seem very pleased with the change. While it is always possible to write very good code in C, C++ has encouraged better coding and attracted some considerable talent to the group to boot. I hope that you are encouraged to study C++ coding. There are many benefits, not the least of which seems to be a tendency to write cleaner, more reliable code. Despite the fact that bad code can be found anywhere in this project, there are a lot of very good examples as well. Regards, Charlie H. Arnt Karlsen wrote: On Thu, 25 Apr 2002 23:11:25 -0500, Michael Selig [EMAIL PROTECTED] wrote in message ..why _is_ FG written in C++ and not C? ... ..oh yeah, I the newbie do see the merits of inertia. ;-) Actually, this group has surprised me in its willingness to consider alternate schools of thought - more so than any other group I've ever worked with. The rule seems to be, that if you come up with a better approach that it is highly likely to be adopted. Beware, however. The combined experience base is tremendous and they've likely seen just about any downside there is to any good idea. This group can be a real education. Regards, Charlie H. -- There are two major products that come out of Berkeley: LSD and UNIX. We don't believe this to be a coincidence. - J. Anderson ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
Re: [Flightgear-devel] OT: Easy on the rudder there, Cowboy
Jon S. Berndt wrote: Also, flex wings are surprisingly robust, even slow beginner nice-weather-only gliders are specified to +6 gs. IIRC the Vari-EZ composite is spec'ed at +12 -6 and Ruttan refuses to divulge the actual limits. (Not that you're going to be awake after pulling +12 anyway.) Reminds me of a picture I saw of a Boeing 757 (?) in a test rig. ...The tips had been yanked up unbelievably high and had not reached their failure point, yet. ... I recall reading that the test limit is 150% of design load limit. That caused me a little concern, but seeing the displacement needed to break the wing helps alleviate some of the unease in watching those wings flex in flight. Too bad there are fools who watch the same engineering marvel and only see another weapon. :-( Regards, Charlie H. -- There are two major products that come out of Berkeley: LSD and UNIX. We don't believe this to be a coincidence. - J. Anderson ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
Re: [Flightgear-devel] Uninitialized variables
Fred, You are correct. However, neither are they classes written by the user. And we routinely get headaches from automatic int, float, pointer variables we forgets to initialize. On the other hand, we do expect the opposite of class objects. In fact, the whole point of a c'tor is that default initialization is predictable. You can't forget to initialize the object in only one place. Regards, Charlie H. Frederic Bouvier wrote: C'tors that don't initialize class members? Ought to have a good reason for that in the class documentation. Otherwise one is writing time bombs in the code. I believe most class members are properly initialized. There are some that may not appear to be, though - that is, the vector and matrix objects in JSBSim. However, when those are created they are initialized themselves. Float, integers and pointers don't initialize themselves. Fred ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel -- There are two major products that come out of Berkeley: LSD and UNIX. We don't believe this to be a coincidence. - J. Anderson ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
Re: [Flightgear-devel] Uninitialized variables
Christian Mayer wrote: Frederic Bouvier wrote: but I think that every member variables should have a default value set in class constructor Definitely!! I had many troubles with MSVC and uninialized variables so far. C'tors that don't initialize class members? Ought to have a good reason for that in the class documentation. Otherwise one is writing time bombs in the code. Regards, Charlie H -- There are two major products that come out of Berkeley: LSD and UNIX. We don't believe this to be a coincidence. - J. Anderson ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
Re: [Flightgear-devel] Engine displacement definition?
Tony Peden wrote: On Thu, 2001-12-13 at 17:13, Christian Mayer wrote: Andy Ross wrote: Dumb question, but one I hope someone knows the answer to: when one specifies the displacement of a piston engine (e.g. IO-360 == 360 cubic inches), is that the volume of the whole cylinders or just of the piston strokes? At a car you are giving the total volume (i.e. all cylinders) of the air that gets compressed, i.e. the piston strokes. plus, depending on the piston design, whatever volume is available in the cylinder head. Sorry, displacement means just that. Piston and head cavity shape can complicate compression ratio (CR) calculations but does not affect those for displacement. Displacement is literally the volume swept (displaced) by the piston. While CR can be used to calculate the undisplaced volume, it is more important in determining power per cubic volume of displacement. To a point, raising the compression ratio of an engine can result in an improvement in power realized (which is why some gear heads mill down the block and or switch to hemi pistons). It can also lead to problems with valve head clearance, knock, over heating, blown gaskets, etc.. I watched a neighbor do all the above with a '68 Chevy Chevelle. He would devote a weekend to fixing his engine and an evening or two every month blowing out a gasket, throwing a rod or something else while racing some other guy with his souped up classic. Very entertaining, after a fashion. Beautiful car. Regards, Charlie H. -- There are two major products that come out of Berkeley: LSD and UNIX. We don't believe this to be a coincidence. - J. Anderson ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
Re: [Flightgear-devel] buildings or planes?
A man after my own heart. How about creating a small airport and jack it up 30 meters from the surrounding terrain? You'll get the same effect without getting seasick.. :-) Charlie H. Andy Ross wrote: Jeff wrote: So my question is: What is more important to FlightGear buildings or planes? For me? Neither: Aircraft carrier! ... -- There are two major products that come out of Berkeley: LSD and UNIX. We don't believe this to be a coincidence. - J. Anderson ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
