Understanding that I have almost no frame of reference (except some YouTube videos), I do have a quick question regarding start-up sounds.1. What is the high pitch sound that cuts out abruptly at around ~60 RPM? I assume it's the starter, but should it cut out abruptly or decrease in volume over some (relatively short) period of time.2. When I push the STOP button (especially when aborting an engine start), there is a gap in sound before the spin-down sound. Is this correct?Thanks for the awesome aircraft!

Jeff,It's probably not a good idea to use those YouTube videos as a reference, since the sound in them was likely recorded using the condenser mic in the hand-held video camera used to make the video.

Jeff,It's probably not a good idea to use those YouTube videos as a reference, since the sound in them was likely recorded using the condenser mic in the hand-held video camera used to make the video.

What I mean is that it doesn't sound right to me, but I don't have a reference point other than youtube...

Sorry, Jeff. I should have been more clear. What I meant was that it probably doesn't sound right because your ear is expecting it to sound like the YouTube video.I believe the whining that you hear cutting out at about 65% RPM is indeed the starter, and I'm fairly certain it does sound like that. During development, there was a lot of work put into making the startup sounds as close to the real thing as could be, and the guys on the team who have actual cockpit time in the JS4100 were very pleased. I don't hear a gap in sound at shutdown (I would have reported it before release if I did), but I do get a tiny delay between when I press the STOP button and when the shutdown sequence starts with its appropriate sounds, and during that time, I hear the engines at idle. There is a lot happening during shutdown, so I wouldn't expect it to be instantaneous when the STOP button is pressed. From the Jetstream manual:"When the STOP switch is pressed this opens the fuel pump/shutdown valve. Purge air goes into the manifolds. This causes the RPM and EGT values to increase momentarily, then a continuous decrease in the two values will occur." So, at shutdown, you're waiting for a valve to open and dump enough air into the manifolds to get the engine to shut down. Hopefully that explains the momentary wait between when you press the switch and when the engine actually starts to spool down.

Sorry, Jeff. I should have been more clear. What I meant was that it probably doesn't sound right because your ear is expecting it to sound like the YouTube video.I believe the whining that you hear cutting out at about 65% RPM is indeed the starter, and I'm fairly certain it does sound like that. During development, there was a lot of work put into making the startup sounds as close to the real thing as could be, and the guys on the team who have actual cockpit time in the JS4100 were very pleased. I don't hear a gap in sound at shutdown (I would have reported it before release if I did), but I do get a tiny delay between when I press the STOP button and when the shutdown sequence starts with its appropriate sounds, and during that time, I hear the engines at idle. There is a lot happening during shutdown, so I wouldn't expect it to be instantaneous when the STOP button is pressed. From the Jetstream manual:"When the STOP switch is pressed this opens the fuel pump/shutdown valve. Purge air goes into the manifolds. This causes the RPM and EGT values to increase momentarily, then a continuous decrease in the two values will occur." So, at shutdown, you're waiting for a valve to open and dump enough air into the manifolds to get the engine to shut down. Hopefully that explains the momentary wait between when you press the switch and when the engine actually starts to spool down.

Thanks Kurt....all great stuff to know. Let me take another listen when I get back into town, and I'll post some follow-up on the shutdown sound. Thanks!