AC Supply is your best friend here....or at least they have been for me in getting C5-3s, A3-2T and A3-6Ts, and assorted Q-Jets.
I may have already said this, but the current C5 time-thrust curve looks so much like the A10 time-thrust curve that I'd be afraid that the models we'd put them in would get a good punch off the pad, but then barely maintain velocity, not accelerate after that initial kick. I see this behavior flying my Checkmate all the time. Some A10s have such a weak "tail" that the model visibly seems to slow down before zipping off when it stages to an A3. FlightSketch accelerometer data shows this pretty clearly, too as a section of barely 1G during the tail of the A10's burn.
Hmmmm, quite possible I am not thinking this right.
concur with both you and
@jqavins that there IS a weak tail that might not be optimal. But from your statements “barely maintain velocity” and “barely 1 G during the tail”, I’m thinking’, “as long as velocity is maintained, if you got off the pad okay (when velocity is slowest) your rocket SHOULD be fine as long as it doesn’t significantly DEcelerate. If your accelerometer is measuring “1 G”, wouldn’t that rocket be at constant velocity (assuming that it’s relatively vertical)?
again, agree with
@jqavins , IF you have a rocket that CAN get off the pad adequately with either C6-0 or non-existent C5-0, due mainly to (I think) the fewer newtons in the C5-0 and possibly the higher initial velocity from the C5‘s larger “spike” increased drag, the C6 is more efficient and is going to stage higher. But my target is not “rockets that could fly on both.” I’m thinking there are rockets that are too heavy (over 113 grams, per Estes motor chart) for the C6 to GET them off the rod with a stable velocity. Once it is safely off the rod, even If the motor tail can only manage 1 G, I theeeeenk velocity should be constant, so what started safe SHOULD stay safe. Even if the tail is less than 1G, is the tail THAT long that the ensuing deceleration would drop it BELOW safe speed during that 1.7 seconds seconds after the spike?
@BEC , you said your Checkmate “visibly seems to slow down” before staging, I haven’t flown accelerometers, so I is ignorant, but does your Data show it is “slowing down” or that is “no longer accelerating”?
the first is potentially a serious Problem. The second is, at worst, inefficient.
I like staging just for the point of staging, not for altitude (the latter with MODEL rockets is generally more easily achieved, at least in low power realm, with single stage bigger motor.). Okay, I do want it to at least get OFF the rod BEFORE it stages (had one that didn‘t, spent 5 or 10 minutes looking for the booster before I thought to look ON the pad!), and I don’t know, at least up 50 to 100 feet before it stages. More than that, meh, doesn’t add much for ME. I kinda like to SEE the staging, and if it is much higher than that, doesn’t add anything and kind of takes away something.
so I think that those of us whining for a C5-0 are doing so because we think it would help use with 18mm mounts that for whatever reason can’t be upgraded to 24mm (which I agree is clearly the way to go IF you can, as
@jmasterj said), and that are either heavier than 113 grams and or extra draggy (which stagers tend to be the FarSide is an excellent example.) Are we wrong about that Due to the “weak tail”?
concur with both you and 
