Ongoing alarm sound after switching strobes on (naturally aspirated B58)
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I just took the naturally aspirated B58 up for a maiden flight. I started from cold/dark at a parking spot and ran through the in-sim checklist until the anti-ice systems check, and then I skipped over most of the anti-ice and autopilot tests. As I was entering the runway, I switched the strobes on and heard a faint siren noise (like an alarm was going off). I checked for any annunciators indicating an abnormal condition and couldn't find any. I unplugged the noise-cancelling headphones from the armrest in the virtual cockpit, and the siren was not audible without the headphones on. Since I couldn't find any indication of a problem, I proceeded with the takeoff, and the engine noise seemed to drown out the alarm. The flight went normally with no issues. After landing at my destination, the siren became audible again after landing when the wind and engine noise were quieter. As soon as I switched the strobe lights off when vacating the runway, the siren stopped sounding. I'm guessing there is a sound bug somewhere, but I'm happy to be corrected if I did something wrong.
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You're hearing the sound of the strobe light capacitors charging, and if you listen really closely, the pops of them discharging. You will only hear this when the avionics are on, and you are wearing your headset, because you're hearing the current induced in the audio system by the high voltage power supplies. It's a phenomenon quite familiar to most GA pilots, but the source of many "bug reports" for me
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For anyone who has ever wanted an example of this, here's just the first video I found where you can hear this effect in a Cessna Cardinal (at Addison, TX, where I recorded the sounds for Starship).
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J jmarkows referenced this topic
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J jmarkows referenced this topic
