CR-7, J-33, J-X4 Engines "Drains evenly stage-by-stage"

[Stigy]

Wgat does it mean that engines drain propellants evenly stage by stage ? Especially for CR-7 - is there any difference of consuming fuel by this engine compared to standard engines ? I know it can run on Air + LF but when it runs on LF+O is there any difference ? If not, what's the point of this description - "Drains evenly stage-by-stage" ?

Thanks in advance.

Edited October 12, 2015 by Stigy

[Vectura]

I think what it means is that for the jet engines (and the rapier in air breathing mode) the liquid fuel will be sucked out of all tanks in the stage simultaneously, which helps with issues with aircraft balance.

[Red Iron Crown]

It means these engines use STAGE_PRIORITY_FLOW instead of STACK_PRIORITY_SEARCH for determining fuel routing. Stack priority is what you are likely used to, with fuel lines and parts that block crossfeed along with draining a single tank (or group of tanks placed with symmetry) at a time. Stage Priority draws from all the tanks in a stage evenly, with stage being determined by the number of decouplers between the tank and the root part.

For the Rapier, this flow mode applies in both rocket mode and in airbreathing mode.

[Stigy]

Ok. Thank You.