Tomvreomfodj

I never managed to actually prove it, since I modified the ship and the problem went away, but I think the problem was that the ship was breaking on the pad, as the first response to this post suggested.

In 64-bit KSP 1.1, with only one mod (the docking alignment indicator) - launching a fairly large rocket (174 tons in 6 stages): If I save and then attempt to load the vehicle, it shows up on the vehicle list as "116 parts in 13 stages", but there are only six stages on the sidebar. I click "launch". I go to the pad. If I don't do anything for a few seconds, the spacecraft settles in. It appears to be intact, but the first three stages disappear from the stage sequence on the left. If I activate the staging sequence, I get the fourth stage. If I hit the "stage" button before the rocket "settles in", stage one fires as it should, but controls then appear to be locked. I have checked visually - in both of these scenarios, the rocket appears to be intact, just the controls are misbehaving. If I leave the pad after the rocket settles in, then come back, the top half of the rocket falls to the pad immediately upon my return and lights everything on fire. I do not see the bottom half. The spacecraft in question has three probe bodies and no crew. I have tried quitting and reloading, shuffling the stage sequence, and similar with no apparent effect. Has anyone seen similar behavior? Any idea how it might be fixed?

I just attempted to post a reply a moment ago, and got an arbitrary click from a touchpad glitch, so you might get one and a half replies. Unfortunately, I can't tell what you can see, because "approved by moderator" came up. In any case, to recap: Upside-down decoupler: I tested installing decouplers the other way around. They behaved differently, arguably worse, as the decoupler ring itself remained attached and eventually exploded due to overheat. However, the fairings stayed on, so no loose bits. Engine nodes: I don't see two nodes available on an engine once it's installed on the fuel tank, so that may be the problem. I tried this with multiple engines to make sure it wasn't model specific. I didn't see any top nodes available, but I did observe that the Poodle engine did not have this problem. Perhaps some engines just aren't meant to have a stage under them, and I'm too new and clueless to know.

This is not with LVN fairings - stock game. Although my events to Google this did frequently return LVN fairings related answers. - - - Updated - - - Thank you for your input. I tried attaching the decouplers up-side down on small test rockets. In that case, the decoupler itself stayed attached to the engine; the decoupler exploded after it reached a certain temperature; and the fairing remained on the engine indefinitely. On the upside, this meant no loose bits rattling around. I also explored your top node suggestion. I don't see a "top node" on any of the engines I tested this on - stick the engine to the fuel tank, and the only green dot visible thenceforth is the one on the bottom. On the suspicion that perhaps some engines had a top node and some did not, I tried multiple engines. I did not see any top nodes, but I did see that this problem did not occur with the "Poodle" engine. Perhaps some engines just aren't meant to have stage seperators under them

A stage separator attached to a liquid fuel engine, as you probably know, creates a sort of fairing around that engine, so that the resulting multi-stage rocket resembles a smooth cylinder. In my brief experience thus far, that tube or fairing remains on the engine after stage separation, but departs forcefully at engine start. I have seen engines or entire rockets destroyed when multiple liquid fueled engines bundled close together have shed that fairing simultaneously. I have also gotten those fairings stuck to other parts of my rocket. Ideally, the fairing would remain attached to the departing stage, but I have found no means of doing this. I have attempted to mitigate this problem by starting "bundled" engines in sequence, but this makes staging messy and is labor-intensive. Starting at low throttle seems to be more helpful, but by no means foolproof. I have also attempted to install the stage separator upside-down, but the editor won't let me, I suspect for good reason. How do you achieve a reliably non-explosive second stage ignition, or at least ensure that the explosion doesn't damage anything important?