August 23, 20205 yr 4 minutes ago, JDLinn said: I’m not a pilot. So tell me, when the D key is pressed, what is supposed to be going on? How would I manually do it, not using the D key? (Does that sync heading have anything to do with it?) As mentioned above, in the real airplane, you align the Heading Indicator with the magnetic compass heading. Bert
August 23, 20205 yr 12 minutes ago, JDLinn said: I’m not a pilot. So tell me, when the D key is pressed, what is supposed to be going on? How would I manually do it, not using the D key? (Does that sync heading have anything to do with it?) Here’s a drawn out explanation: Aircraft have two instruments related to your direction - (1) the magnetic compass, which is usually on top of the dashboard, and (2) a heading indicator. Magnetic compasses are problematic to read during flight because they are inaccurate / move every time the aircraft undergoes acceleration. The solution to this is to use a gyroscopic heading indicator. The heading indicator works by using engine vacuum power to spin a gyroscope very quickly. A tendency of gyroscopes is to remain in the 3D plane they are in if spinning quickly enough (imagine a bike wheel spinning very fast - the faster it spins, the more difficult it is to turn it sideways - this is why it is easier to balance when the bike is moving quickly - the wheels want to remain in their plane). Therefore, when the airplane turns, the gyroscope stays spinning in the same plane, and the difference between where the gyro is spinning and the aircraft is how a heading is displayed. Why do we need to reset the heading indicator to match the magnetic compass often? As time goes on, the heading displayed becomes inaccurate due to friction and other forces acting on the gyroscope. Every 15 mins or so, it is important to look at the magnetic compass and align the heading indicator to match it using the knob on the left. This is what is automatically being done by pressing “D.” Check out this video: Part of the Embry Riddle “PACE” series - you should watch as many of these as you can 🙂 Edited August 23, 20205 yr by FlyingInACessna
August 23, 20205 yr 1 hour ago, FlyingInACessna said: In reality, all of the C172s I’ve flown definitely precess more than 1° in 15 mins. Maybe closer to 3-5. That being said, I haven’t found that the sim even models precession. Does anyone have evidence that it does? My heading indicator always seems aligned to the mag compass. Sometimes it’s 1-2° off right after engine start, and then I won’t touch it for the rest of an hour long flight. Realistically, it should be several degrees off on engine start. Options/Assistance/Aircraft Systems/Gyro Drift Autocalibration/ Turn it off Semper Fi
August 23, 20205 yr 22 minutes ago, JDLinn said: I’m not a pilot. So tell me, when the D key is pressed, what is supposed to be going on? How would I manually do it, not using the D key? (Does that sync heading have anything to do with it?) D suppose to alight heading indicator with compass. Since in real life heading indicator has spinning gyro , due to friction it precess. So once in a while you suppose to align with a compass by using adjustment knob on the gauge. also worth mentioning, compass has to have a card with adjusted variations for different heading (since each airplane electrical system effect compass differently) flight sim addict, airplane owner, CFI
August 23, 20205 yr Author OK, THANK YOU!!! For all the great information. "Flying in a Cessna" ... that was a VERY helpful explanation and now I better understand the process of what is happening. I solved the problem using JoeC63 ... I turned that gyro off and the "notification" has not returned. (Now I'll probably wind up in Egypt instead of Newark! 🙂 Thanks everyone! Doug
August 23, 20205 yr 23 minutes ago, joec63 said: Options/Assistance/Aircraft Systems/Gyro Drift Autocalibration/ Turn it off I’m pretty sure I already have every assistance setting off, but good to know that’s there. Thanks!
August 23, 20205 yr 10 minutes ago, JDLinn said: OK, THANK YOU!!! For all the great information. "Flying in a Cessna" ... that was a VERY helpful explanation and now I better understand the process of what is happening. I solved the problem using JoeC63 ... I turned that gyro off and the "notification" has not returned. (Now I'll probably wind up in Egypt instead of Newark! 🙂 Thanks everyone! Doug Of course! Glad to help.
April 24, 20233 yr Can anyone tell me how to calibrate a gyrocompass in the sim now? Pressing D no longer seems to work.
April 24, 20233 yr 2 hours ago, Ian Cooper said: Can anyone tell me how to calibrate a gyrocompass in the sim now? Pressing D no longer seems to work. I should do, unless your key bindings have changed. Rob (but call me Bob or Rob, I don't mind). I like to trick airline passengers into thinking I have my own swimming pool in my back yard by painting a large blue rectangle on my patio. Intel 14900K in a Z790 motherboard with water cooling, RTX 4080, 32 GB 6000 CL30 DDR5 RAM, W11 and MSFS on Samsung 980 Pro NVME SSD's. Core Isolation Off, Game Mode Off.
April 24, 20233 yr 2 hours ago, Ian Cooper said: Can anyone tell me how to calibrate a gyrocompass in the sim now? Pressing D no longer seems to work. What do you mean by "gyrocompass"? The D key calibrates the heading indicator, is that what you mean? Bert
April 24, 20233 yr Maybe he's got a Spitfire, or perhaps, a B25, and thinking about the magnetic compass, and wanting to know if we should swing them every now an then . . . . . .https://www.aviationconsumer.com/maintenance/compass-swings-a-forgotten-task/😁 i7 [email protected] | 32GB RAM | EVGA RTX 3080Ti | Maximus Hero VII | 512GB 860 Pro | 512GB 850 Pro | 256GB 840 Pro | 2TB 860 QVO | 1TB 870 EVO | Seagate 3TB Cloud | EVGA 1000 GQ | Win10 Pro | EK Custom water cooling.
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