The Ion-4 is a fictional (although realistic) launch vehicle with a payload capability of around 12,000kg to low earth orbit. It is designed to be as inexpensive as possible, thereby reducing launch costs. First stage attitude control is done via engine gimballing with four hydrazine thrusters for roll control. The second stage engine is fixed, attitude control is accomplished entirely via hydrazine thrusters. The second stage has limited +Z translation ability.
Launch autopilot – Activate the autopilot at T-10 seconds. If your target perigee is higher than 250km or so, the autopilot may not work right… you have been warned.
Custom fairings and payload adapter – The default 5 meter fairing can be replaced with your own custom fairing and a custom payload adapter can be added, see the manual about .cfg file parameters
Countdown autosequence – Personally, I think this one is really cool. The launch vehicle goes through the entire countdown sequence, then launches at a specified time. Must be enabled in scenario, see the manual about scenario parameters.
First stage engine gimballing – The RS-68B engine on the first stage has 3 degrees of gimballing capability, providing pitch and yaw control. The engine bell actually moves, as does the engine exhaust. If the autopilot is not running you can fly it manually (better have a joystick), or you can do an engine gimbal checkout on the pad before launch.
Launch pad features – The launch pad features an animated Launch Service Tower, as well as flame bucket effects.
Second Stage G-Limiter – The second stage will automatically throttle down to maintain a 7 g acceleration cap on the payload.
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