ASAS can be skipped too, but only if you're a masochist
Not for me. Especially if you have a big stack with thrust vectored mainsails, skipping out on ASAS means the thrust vectoring ability is wasted when in SAS mode and without it a big stack is unstearable when you've already skipped the RCS's.
Probably. I tried a single mainsail with 8 smaller liquid engines around them (the non-thrust vectoring kind), but my rocket didn't have enough power to get off the pad. My 7-mainsail is the only thing that has worked so far, and only just barely.
You have probably grossly over-engineered the thing. I'd start from scratch with a much smaller rocket. I have the same problem in that I always assume bigger is better, but if you work out the thrust/weight ratios, you actually end up with much less DeltaV from your lower stages than is optimal if you build a monster rocket.
Unfortunately, you can't use multiple mainsails easily with one stack (like the 5 F-5 engines at the bottom of a Saturn V) so you have to add more tanks to support more engines. But adding more tanks means you have to add more engines, which means more tanks and so on.
The reason my friend did so good last night is he only had one main stack surrounded by three booster stacks, each with a mainsail. But instead of adding like 9 tanks to each stack, (as I would) he just had 3 or 4. It got him into orbit and started his Munar injection burn. The lander had enough fuel for the rest. It was glorious - his stack did what my mega stack does only on a perfect launch with fuel to spare. (Also, make sure you are using fuel lines to connect the bottom of your side boosters to the main stack so that even though the main stack is firing with the boosters, upon separation it will still be fully fueled)
So go smaller - also, rip off successful Youtube videos if necessary.
For your tumbling problem, what kind of semmetry are you using? My main rocket has four boosters around a central core with mainsails. I tried adding more fuel to the lander by using triple symmetry to attach fuel tanks to it. It turns out mixing triple symmetry with quad symmetry is bad idea and it rolls and tumbles uncontrollably. Are you doing something like this?
One last thing, a rocket I ripped off Youtube has 8 smaller engines clustered around your mainsail and it works perfectly. Are you staging it so that the mainsail fires when the booster fire on the pad? They all need to go off at the same time or it won't get off the pad. Take the mainsail engine (and nothing else, not it's tanks and certainly not it's decoupler, just the engine) and put it in the same stage as the boosters, but don't change anything else. That way it will fire the whole time but when the booster separate, even if the mainsail is in the same stage as them, it won't fall off until it's own decoupler has been activated.
This game is AMAZING, i bought it a week or so ago ;D I actually have some videos on my YouTube channel if anyones interested ;D
Anyone else looking forward to the next patch as much as me? Docking sounds awesome
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