Speed up and Slow Down notifications are the settings can be used to inform your members that your aircraft has taken off or landed. This function is enabled under your Aircraft Settings. Select the aircraft and scroll down to where you have the Spider assigned.
Putting a green tick in the Enable box will activate this. You are able to set your own transition speed, 40 knots is the default setting. A position report will automatically be added to the maps and the notification be sent to those members you have selected to receive this notification.
Please note that speed up and slow down messages are not sent when using Automated Watch. When using Automated Watch the enable transition speed option will determine when Automated Watch starts instead.