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Hi all. I'm about 98% finished my Hornet HUD, and it's coming along really nicely. There is an issue with the pitch ladder (it only goes up to 50 degrees), and it taking REALLY big bitmaps to make one work properly, but besides that it works great. The velocity vector seems very accurate. Now, about that.... are there any internal sim variables such as "screen width, degrees" and location of the actual horizon which I could use to lock my HUD to?? I've looked but don't see any. The gauge works very well, but as soon as someone messes with its size or the view zoom or pan it's going to be inaccurate. It would be nice if there were a way to have the sim "tack" my HUD horizon line to the sim's "real" one, and auto-adjust the deflection of the velocity vector and distance between the pitch ladder lines accordingly.... Okay, that second part is probably me dreaming, but I have an inkling that the horizon-lock may be possible in some way. Anyone? Is there ANY way around this problem at all??? Thanks!

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Our Hornet doesn't use bit maps at all (pic attached). If you use vectors, or even text blocks for your pitch ladder, you won't have to worry about huge bitmaps, and you can even manupulate the colors (brightness, etc).If you calibrate the pitch ladder initially, then you can use the Attitude Indicator Bars Position variable to adjust it (I don't have the SDK handy, but you'll see it). You can then adjust some L:Var based on the zoom factor, eyepoint, whatever.Keep in mind that the horizon bar isn't always going to be on the VISIBLE horizon. The higher you go, the lower the apparent horizon will appear - that's normal and natural. What's important is that your horizon bar is a REFERENCE for your velocity vector. If the VV is above the horizon bar, you're ascending, below, descending, etc.Good luck with your project, and post some pics:)--Jonhttp://forums.avsim.net/user_files/118530.jpg

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Hey, thanks for the advice. This is the first gauge I've done,so I need all the help I can get!! That's a nice looking HUDyou posted there. I can appreciate the work that went intothat. ;-) A pic of the one I just did is attached. Can I askyou, do you have the ILS needles center on the velocityvector, or on the waterline mark? I've seen it done both waysin various sims. My angle of attack bracket is"attached" to the vector.... There is so much I'dlike to add, but I'm really just doing it for myself. I'llquit tinkering once I get it to a point where it can autoadjust its size. Thanks again.By the way, is that Hornet for sale or download? I did abrief search but couldn't find much on "F/A-18" andVertical Reality.Scotthttp://forums.avsim.net/user_files/118584.jpg

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Hey, Scott, that's a great looking HUD of yours. It looks like you're doing your homework:)To answer your question about the localizer AZ/EL bars, they are referenced to the Velocity Vector when the waterline is NOT displayed (i.e. when the gear is UP). So during approach with gear down, they'll be centered on the waterline, otherwise the velocity vector. You'll want to remove the waterline when the gear is up as well.Do try to use vectors as much as you can. Again, there's no need for bitmaps. You'll find lots of info by searching the forums here for "vector", and you can use the GPS in FS9 to hack apart.>There is so much I'd>like to add, but I'm really just doing it for myself. I'll>quit tinkering once I get it to a point where it can auto>adjust its size. Thanks again.That's what I said 3 years ago:) Since then I've added untold thousands of lines of code and it's still not finished. This will be a commercial product, but it has not been announced yet, so you won't find any info to speak of. Bascially what we're doing is simulating the entire flight manual. I've been too busy to even set up a website because we're trying to ship this year, but we're going to be hitting the marketing trail very soon now.Here's a bit of a higher res shot showing some HSI symbology.Good luck with your project, and don't be shy about asking more questions if you hit a wall. Lots of helpful people here.--Jonhttp://forums.avsim.net/user_files/118604.jpg

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You guys have great looking cockpits. Just to let you know what kind of an obsession this can be, I've written thousands and thousands of lines of code over the past four years for my F/A-18E cockpit. The gauge file is 10.5 MB and growing. I'll post a couple of screen shots of my cockpit. Keep up the good work!

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Hey William,Great to see yet another Hornet under construction, and it does look like you've got some interesting avionics (working radar?) I know what you mean about how obsessive things can get. It always seems to start out small and innocent:)--Jon

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Hi Jon, what's that variable watcher thingy I can see in your shot? Is it available somewhere?nick

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Jon, Yes, that's a working radar. I really have to give all the credit to Arne Bartels. I had a couple of ideas and Arne already had a working TCAS gauge and the next thing I knew I had a working radar. I've tried to model most of the avionics as close as I can to the real F/A-18E. I've taken some "minor" liberties. The real F/A-18 doesn't have yellow ils needles on the ADI, nor does it have the cute little aircraft cartoon showing the gear and flap status. My HSI is similar to the F/A-18, but it doesn't show TACAN location symbol or waypoint symbol. I do have a very realistic fuel display and my master caution does control the various cockpit voice warnings. My up front control panel is partially functional. For now, I can key in the radar altimeter warning altitude, and the scratch pad defaults to showing longitude, latitude, waypoint id and distance (if a flight plan is loaded).

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William,Actually the ADI does have yellow bars on the EADI if the color option is selected in from the tactical menu. Those are actually tri-color DDI displays (red, green, yellow), but color is generally only used for BIT display status, ILS bars, and menus. Color is optional based on selection from the TAC display.The 'cute little aircraft cartoon' you mentioned does not appear in the NATOPS manual, however:)My scratchpad is pretty much finished now. It checks for valid data for radar alt, baro alt, and baro secondary alts, com and nav channels and frequencies, UTM coordinates, and probably a dozen other functions including SINGARS and Have Quick simultion. The UFC in the E is tightly integrated with the DDIs, particularly from the HSI data sublevels where several menu functions bring up UFCD scratchpad prompts.The HSI shows TACAN and waypoint symbology as well. If you're interested in doing that, you can plot the position based on range and bearing and shift accordingly based on map scale.--Jon

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>Hi Jon, what's that variable watcher thingy I can see in your>shot? Is it available somewhere?>nickHey Nick,That's just a windowed gauge that I use to display the values of variables I'm working with at any given time, nothing more. I just edit the gauge from time to time to show different variables.--Jon

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Jon, Thanks for the info/feedback. As many times as I have read the NATOPS, I didn't pickup on the DDI's as being tri-color. I'll look it up when I get in the office tomorrow. My cockpit has a look down mode, where the multi-color display can be seen. I've built several versions of a flightmap gauge that I display there. I'll think about reprogramming my HSI to show waypoints and TACANS (there goes that obsession again). Do you have working FUEL SYS and FPAS displays? Bill

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Hey, Bill.The support suppliment NFM-000 refers to color as being an option accessed from the Attack display, and specifically mentions yellow ILS bars on the DDIs, but the specific information can only be found in the Tactical manual which may be tricky to obtain:)--Jon

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Jon, Thanks again. I'm impressed, you've got the correct radar symbology. I cheated by displaying a delta altitude next to each radar target along with a pointer that shows target direction of flight. I also programmed into the display such that when I clicked a target with my mouse, it would highlight the target, show Vc and simulated antenna elevation and show on the HUD a target symbol, steering cue, and range to target, time to intercept, and closing velocity. I wasn't sure how to extract the performance data from the ".air" file in order to compute the correct info for the FPAS. So I modified the display to show time, distance and fuel burn for 1) next waypoint, 2) bingo fuel, 3) 2000 lbs fuel, and 4) zero fuel. Double check your labels for the fuel display. What you've labeled as tank 2, I've labeled as tank 4. I've also programmed the fuel burn sequence as 1) external wing tanks, 2) external centerline tank, 3) internal wing tanks, 4) tank 1, 5) tank 4, 6) left and right feed tanks. I'll see if I have a copy of the Tactical manual in the safe. If not, I'll review my note books from TOPGUN ground school that I took a couple of years ago. Bill

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Bill,You can't extract the needed coefficients for the FPAS from the .air file, so you have to calculate them based on known constants such as CLa, Alpha_0, CDo, K S, etc. These will lead you to CDp, CDi, CL and CD which are the magic coefficients needed to get the correct R and Es at reference speeds. You can use AFSD to give you the constants you need to work with your flight model. It's also very good for checking your numbers against. You can do all sort of other things with the calculations as well. For instance I have a function that takes a reference AoA and converts it to required airspeed for Approach mode autotrottle. Just plug in 8.1 degrees and the AT holds it.I don't want to make it sound easy, it's not (at least for me), as I have no aerodynamic background. I've also had lots of help from folks like Ron Freimuth who has done similar calculations for his own work with flight models. Mostly I just learn what I need to know to get the job done, but even that takes me forever.Regarding the fuel display, I did double check and you're right: It should be TK 4, not TK 2. I have not yet programmed the fuel system, as I haven't decided how far to take it yet, but it will obviously need to feed properly from 2 and 3 at the very least.I do simulate scan volumes with the radar; if the target is not within the current volume, you'll lose it unless it's STTed, and even then I simulate the gimbal limits so that lock can be broken. I also show the target's relative heading, corrected for B-sweep, so that when the aspect tail is pointing towards the bottom of the screen, it's heading directly towards you.It's great that you have access to the Tactical manual - I wish I did:) I assume you must have flown Hornets? I have to rely on what I know from having done Hornet simulations back in the 90's. I also keep a copy of Jane's F/A-18 around when I get desperate for info, even if it's not always accurate:(--Jon

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Jon, Thanks again! I was so "lock in" on one approach for calculating performance that I didn't think about the obvious. It's good to get a second opinion. Also, I was just curious how you did your fuel sequencing. I know mine is "close". On the real Super Hornet, once the external fuel is gone, fuel is transfered from the various internal tanks to control the cg. The two feed tanks are the last to empty. You obviously have a very complex radar model. I put my radar gauge together to just show air traffic so I can do radar intercepts. Nothing like the real Hornet. I'm a civilian engineer for the navy, stationed at NAVAIR HQ. I do have a few flight hours in military jets, but none in a Hornet or Super Hornet. I have had access to the real Hornet simulator here and at St. Louis, logging maybe a half dozen flight hours. Bill

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