MartinJ Posted January 17, 2014 Report Posted January 17, 2014 (edited) Hi folks, today I tried a short flight from the co-pilot's point of view. One thing I noticed is that I can't move the speed bugs on the ASI. From my mouse indicator I can see that the bugs are actually moving but the 3d-bugs remain in the same position. It seems that the connection between the speed bug logic and the visualisation is missing. Besides this little bug I am struggling with some graphical artefacts which appear from time to time when I am using the Saab. The artefacts are long and narrow triangles which appear on the virtual cockpit 3d model and are visible for maybe 1/10 second and then they disappear again. I have already updated the driver of my AMD Radeon HD 7900 but without success. Since every other plane doesn't have this issue it might be caused by the Saab. Maybe one of you guys knows a solution for this issue? best regardsMartin Edited January 17, 2014 by MartinJ
JGregory Posted January 17, 2014 Report Posted January 17, 2014 From my mouse indicator I can see that the bugs are actually moving but the 3d-bugs remain in the same position I'm not sure what this means… What is a mouse indicator ? Do you mean the cursor changes? and…. how can you see the bug moving if they remain in the same position ?
MartinJ Posted January 17, 2014 Author Report Posted January 17, 2014 Yes, the cursor changes. I can move the cursor over the speed bug and drag it to a new position even though the new position is only visible due to the changing cursor symbol.
Goran_M Posted January 17, 2014 Report Posted January 17, 2014 (edited) The speed bugs might be my fault. I'll have a look at them sometime this weekend and see what's going on. Edited January 17, 2014 by Goran_M
MartinJ Posted January 19, 2014 Author Report Posted January 19, 2014 Hi Goran, thank you for your quick response. Maybe you can help me with another issue I experienced. This time it is related to the cabin air pressurization. The flight starts at Niederrhein airport with all weather settings set to standard. The landing altitude is set to the field elevation of 106 ft, the baro setting is set to 29.92 and the auto/man switch is set to auto. The differential pressure indicator shows zero. After engine start and bleed air activation the differential pressure remains at zero. So far so good. Now I open the weather menu and change the baro pressure to 29.50. After this I reload the Saab and set the landing elevation to 106 ft again and the baro setting to the new value of 29.50. After I set the batteries to on the differential pressure reads zero, which is correct since the outflow value is assumed to be in the fully opened position. After engine start and activation of bleed air the cabin rate drops to -500 ft/min until a differential pressure of 0.2 psi (29.92 - 29.50) is reached. Since the cabin air pressurization can't produce a vacuum on ground there has to be a bug in the system's logic. best regardsMartin
JGregory Posted January 19, 2014 Report Posted January 19, 2014 Martin, I will check the logic when I get a chance.
MartinJ Posted January 21, 2014 Author Report Posted January 21, 2014 (edited) Hi guys, here is one more question for you. The superb performance charts which are delivered with the Saab offer e.g. max takeoff power charts for four different configurations: a ECS off & ENG A/I offb ECS off & ENG A/I onc ECS on & ENG A/I offd ECS on & ENG A/I on The charts from page 32 to 37 which represent the V-speeds only cover configurations a, b and c. So I was wondering what the V-speeds look like for configuration d. Thank you! Edited January 21, 2014 by MartinJ
JGregory Posted January 21, 2014 Report Posted January 21, 2014 (edited) Maybe you can help me with another issue I experienced. This time it is related to the cabin air pressurization. The flight starts at Niederrhein airport with all weather settings set to standard. The landing altitude is set to the field elevation of 106 ft, the baro setting is set to 29.92 and the auto/man switch is set to auto. The differential pressure indicator shows zero. After engine start and bleed air activation the differential pressure remains at zero. So far so good. Now I open the weather menu and change the baro pressure to 29.50. After this I reload the Saab and set the landing elevation to 106 ft again and the baro setting to the new value of 29.50. After I set the batteries to on the differential pressure reads zero, which is correct since the outflow value is assumed to be in the fully opened position. After engine start and activation of bleed air the cabin rate drops to -500 ft/min until a differential pressure of 0.2 psi (29.92 - 29.50) is reached. Since the cabin air pressurization can't produce a vacuum on ground there has to be a bug in the system's logic.Martin, Thanks for reporting this issue. You were right… there was a bug in the pressurization system that was not opening the outflow valve when the aircraft is on the ground. However, just to be clear… please refer to Pg. 163 of the Systems Manual, Pre-pressurization Mode, where it describes how, when the outflow valve is closed, the system WILL allow for pressurization to 140 feet below actual cabin altitude. So, during taxi and the takeoff roll you may see the cabin rate drop when the system engages (PL beyond 64 degrees). Edited January 21, 2014 by JGregory
MartinJ Posted January 21, 2014 Author Report Posted January 21, 2014 (edited) I am glad to hear that. Do you have any idea why I always get a master caution when I extend the landing gear with the anti skid-switch set to on? Edited January 21, 2014 by MartinJ
JGregory Posted January 21, 2014 Report Posted January 21, 2014 I am glad to hear that. Do you have any idea why I always get a master caution when I extend the landing gear with the anti skid-switch set to on?This is a known issue. The fix will be in the next update.
MartinJ Posted January 22, 2014 Author Report Posted January 22, 2014 Thanks for your answer. I am looking forward to it. Any suggestions regarding my previous question from post #7?
JGregory Posted January 22, 2014 Report Posted January 22, 2014 Thanks for your answer. I am looking forward to it. Any suggestions regarding my previous question from post #7?We do not have a chart for that configuration.
MartinJ Posted January 25, 2014 Author Report Posted January 25, 2014 I have just done a short flight from Weeze to Paderborn. Here are two more things I have noticed: 1) No ground speed indication after landing. Just three dashed lines.2) The fuel used indicator reseted automatically after I switched off one engine. Is this what it is supposed to do? best regardsMartin
JGregory Posted January 25, 2014 Report Posted January 25, 2014 (edited) 1) No ground speed indication after landing. Just three dashed lines.There needs to be a valid DME signal in order to display ground speed. 2) The fuel used indicator reseted automatically after I switched off one engine. Is this what it is supposed to do?The fuel used system requires power from the Right Main Bus or it will reset. When you have a "new" subject to discuss, please start a new thread. These latest questions have nothing to do with the airspeed indicator. Edited January 25, 2014 by JGregory
MartinJ Posted January 25, 2014 Author Report Posted January 25, 2014 Please excuse that I write in this thread again, but my post is related to your answer. You wrote that the fuel used indicator is supplied by the right main bus. But why does it reset when I switch its energy supply from right main bus to left main bus (via bus tie relay) by setting the right generator switch to off? Shouldn't the bus tie relay close immediately and thereby prevent the fuel used indicator from being reset?
JGregory Posted January 26, 2014 Report Posted January 26, 2014 Please excuse that I write in this thread again, but my post is related to your answer. You wrote that the fuel used indicator is supplied by the right main bus. But why does it reset when I switch its energy supply from right main bus to left main bus (via bus tie relay) by setting the right generator switch to off? Shouldn't the bus tie relay close immediately and thereby prevent the fuel used indicator from being reset?Martin, Can you describe what scenario requires you to turn off the right generator, except at the end of a flight? Just curious.
MartinJ Posted January 26, 2014 Author Report Posted January 26, 2014 (edited) Hi Jim, after reaching the parking position I switch off the right hand engine so that I can connect the GPU. After the GPU is connected I shut of the left hand engine and open the doors. Thereafter I usually compare the flight plan data (fuel used, flight time) with the actual data. This is how I noticed the issue with the fuel used indicator. Edited January 26, 2014 by MartinJ
JGregory Posted January 26, 2014 Report Posted January 26, 2014 Martin, Here's the situation… When dealing with relays there is a "chain if events" so to speak. So, when you shut off the left generator, several relays are opened… and this is not instantaneous. The reset of the fuel used is "getting caught" in the process between the generator relay opening and the bus-tie closing. I have a method to fix this but I cannot say when it will get done. In the meantime, I would suggest you note your fuel used prior to shutting of the generator.
Goran_M Posted February 1, 2014 Report Posted February 1, 2014 Back to the original post, speed bugs have been fixed and will be included the update.Locking this thread now as the original post has been addressed. If there are any other questions, please start a new thread.CheersGoran
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