![Can anyone tell me what this alarm sound relates to? It stops when APU or ground power are applied. Can be heard inside and outside aircraft. : r/flightsim Can anyone tell me what this alarm sound relates to? It stops when APU or ground power are applied. Can be heard inside and outside aircraft. : r/flightsim](https://external-preview.redd.it/can-anyone-tell-me-what-this-alarm-sound-relates-to-it-v0-Qtsv9ErlwY9t7LPl-BtDYb0yFAPnKZ4J7TiVXo6COc4.png?width=640&crop=smart&format=pjpg&auto=webp&s=b2430099005ed39b1f863c4fbda361dfb7f45146)
Can anyone tell me what this alarm sound relates to? It stops when APU or ground power are applied. Can be heard inside and outside aircraft. : r/flightsim
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