Leaderboard

WARNING...Geek talk. The LNAV and VNAV calculations are deterministic, the 'performance database', is of course stochastic. The only way to get a fully deterministic implementation is to have air density and vector info predicted at every point surrounding the plane during the flight.....quite the CFD problem (and then some). For the given database input states to the routing algorithms, the output will be the same every time for the same inputs (numerical round-off notwithstanding).....as the calculations are fully based on Newton's laws. -tkyler

Indeed, there is quite a bit you can't see from the videos and screenshots...and also, its not just one or two folks, but 1000s that will trying all differing things, making for 100,000s of possible combinations that might be entered into the FMC. So while we are definitely not striving for perfection, as evidenced by our "whats not in V1.0" list, we do have to ensure that the basics desired are in. To elaborate further, the "desired basics" are those FMS functions that We ourselves as simmers have always said with other products, "I wish the FMS did X....or Y, etc. It turns out the X and Y is a pretty long list of stuff and you take for granted just how many things, as a coder, you have to account for. For example, I'm going to throw Jan under the bus here a bit to illustrate. Jan tells me once, "cruise phase is always in mach". Ok...cool...I made that happen. THEN...a good while later, Jan flies a flight with a cruise altitude under 10,000...where the speed restriction altitude is 250 kias. Jan comes back...."hey Tom...these cruise value should be in KIAS"........"OH...so you mean cruise phase is always in mach, except for condition A.........um....is there a condition B I should know about too? A C perhaps?" Sorry Jan! So things from a coding perspective are not as simple as they may seem on the surface. While maybe 95 out of 100 flights will probably never use cruise altitude below 10,000', some will..and we have to anticipate that before hand and handle it. It turns out there is a whole lot of these situations. The good news is that we believe our V1.0 FMS feature set is complete and we are "testing/calibrating" the performance while we simultaneously clean up textures, loose ends and docs. -tkyler

Indeed in most I agree. So I know some folks are curious just what takes our time...and Jan found yet another interesting bug that resulted in what we call a 'soft crash'....enough to cause the FMS to be useless in this scenario. So when you input route data (procedures), the FMS does all its 'calculating bizness' as you press the buttons, but when you enter a procedure for the first time in a new route, some variables like "true course to next waypoint" don't exist until the calculation has run at least once. Well the legs page shows these values and if you happen to have had the copilot CDU on the legs page while you enter say, a arrival procedure, then the copilot CDU tries to access these values so it can display it....and being they didn't exists yet, would cause a soft crash. The solution was as simple as testing if the values exist of course, standard stuff .... but unless you happen to have the copilot CDU on the legs page WHILE entering the first procedure of the route and WHILE doing so only in the air...you (me actually) would never see this bug because I rarely use both CDUs, except during ground testing and never try to enter data while in the air (need to be coding, not flying). Such is Jan's existence and thoroughness though, I am impressed what this guy finds. It will bode well for all of us I think! -tkyler

I have liked this despite not understanding a word you said.

Count your blessings when you've a tester with deep systems knowledge and a large stamina. Happy bug hunting

I personally appreciate the amount of time the IXEG team is putting in to ensure the release is as bug-free as possible. Unfortunately I've had to stop visiting this forum as often as the amount of whining about the release date is irritating to read. Please grow up people, it will be released when it's released.

I think us not in the developing part of the process do not know the full extent of the issues that are keeping them from release. They have real life 737 pilots working on this aircraft. They will know what a realistic simulation is much better than we will. They will release it when they are happy with it, which will make it more likely that the customers will be happy with it. Any debating this is pointless and counterproductive. They have said it will be coming soon, and once we have it we will be able to fly it for many years. A few more weeks isn't long to wait.

Clouds more than 50km away are, as Cameron said, drawn as "dynamically generated imposters." In order to preserve performance, we draw these distant clouds as 2D textures, and only update them when your viewpoint moves by some significant amount. The other big flight simulators use a similar trick as well. Usually it's not too noticeable, but if you're moving at high speeds and looking sideways relative to your motion, you start to see how the illusion works. As you've already found, bringing in the draw distance to less than 50km eliminates the imposters, leaving you with only true 3D clouds in the scene. It's working as intended; it's a trade off between perfection and performance.

That sounds great. thanks.

Exploring the French and Swiss Alps at dusk