Automatic switching of air breathing rocket engines

[Kolago]

If I take of with an automatic switching air breathing rocket engine there is a point when the thrust falls down under the thrust of the rocket mode. But the auto switch only kicks in after thrust falls down to zero. Is there a way to configure the engine to auto switch earlier?

[A_name]

You can put it in Manual Switching Mode and bind the "Switch Mode" option to an action group. That way you can switch whenever you want.

[Venusgate]

Also consider switching your intakes closed as even after you dont have enough air to feed your engines, an open intake at any altitude has drag.

[GoSlash27]

FWIW, I haven't bothered closing intakes since the 1.00 update. As far as I can tell, closing intakes has absolutely no effect on drag anymore.

Best,

-Slashy

[Wanderfound]

You can switch them earlier, but you shouldn't. Altitude is speed in the bank; milk those hyper-efficient airbreathers for as much height as you can. Keep the AoA low so you don't lose too much speed [1], but try to float up to the jet ceiling before lighting the fireworks.

I normally switch over from jets to rockets just below 30,000m.

 

[1] Low AoA while the engine is low-thrust, that is. Crank it up over Mach 4 while below 20,000m (careful with the heat), then pull into a sharp zoom climb to boost your apoapsis close to 30,000m. But then lower the nose back down to prograde and keep it there while you wait to reach 30,000m and switchover to rocket mode. Pull the nose back up to 45° when the rockets start, flatten off at the top.

Edited December 1, 2015 by Wanderfound