Dickie Crickets

Thanks for the responses everyone! You are indeed correct; I didn't even think to look in the log. It is correct from a physics standpoint, but craft that worked in 0.24 have no thrust in 0.25, without me making any changes to them. That's why I posted the bug report. Was this intentionally modified in 0.25? I have a lander that worked fine in 0.24 and now has no thrust in 0.25. There's nothing wrong with the feature itself, but it'd be nice to have some sort of in-game indication this was happening (the silent warning in the log doesn't count). Or even better - show me the exhaust/aerodynamic colliders in the VAB when I'm installing parts so I can be sure I'm avoiding the problem. A few inches can make all the difference in the world: This guy flies fine without any damage to the lower engines, this one is completely inoperable. Ah, the lack of consistency with RCS is potentially confusing. I feel like I can mount an RCS thruster inside of other components, on Jeb's back, wherever and it'll work fine. The only bother is that I have some expensive landers in orbit around Minmus that aren't usable, but you've just saved my career-mode pocketbook (and some Kerbonauts ). Thanks!

KSP Version: 0.25.0.642, 32 bit What Happens: Radially mounted engines provide no thrust if other parts are mounted directly beneath them. Mods / Add-Ons: None. Steps to Replicate: Download tester craft file, it should look like this: http://i.imgur.com/SYu0bpb.png Launch craft. Go to full throttle and activate all the stages (like a proper Kerbal pilot) Notice that the vehicle is going nowhere. Revert to VAB Move the landing gear such that they're offset from the engines and there is nothing radially mounted beneath them. Screenshot of the setup (the lower set of engines can be mounted higher on the tank and the result is the same). Launch and notice that the vehicle moves just fine. Result: When parts (such as landing gear) are mounted below radial-mount engines (such as the Rockomax 24-77), the engines have no influence on the vehicle's velocity despite still burning fuel and making lots of noise. Fixes/Workarounds: Offsetting the engines and landing gear such that the exhaust has a clear path to the bottom of the aircraft causes the vehicle to accelerate properly. Other Notes/Pictures/Log Files: Testing screenshots with some notes. Some of those screenshots have mods in them, but this bug also repro'd with 0 mods.

I played with this a little today after having two landers smash into Minmus. It appears they work on some vehicles and not others. My mun lander that uses the IL-40 engine works no problem, both on the mun and on the launchpad. My minmus landers - which are of a very similar design - receive zero thrust from their IL-40s. They'll make fire and noise while burning fuel, but there is zero acceleration happening either in space or on the launchpad. My mod set has not changed since 0.24, where this didn't happen. Another thing to note is that in the VAB, the ILX-40 defaults to being upside down. No clue if these are related. Edit: This isn't a BD-specific issue. Bug report thread Did some more testing with an almost-stock and a stock craft. Both my normal mod installs, and a completely stock install. Craft file with BD parts. Should only need BD and Mechjeb installed. Stock craft file. Testing screenshots with some notes. This appears to be a problem related to vertical alignment of the engine and other radially mounted parts (I've tested landing gear and some other random junk). If the exhaust doesn't have a clear path to the bottom of the spacecraft, there is no acceleration applied. If the radial mount engine is positioned directly above the landing gear, it has no effect on the vehicle's actual acceleration. Offsetting the engine and landing gear makes everything work fine. Stock radial mount engines don't have this problem. <- Not true! Rockomax Mark 55 engines don't appear to suffer from this. Rockomax 24-77 (the little orange ones) do repro this bug. [*]This happens with stock landing gear as well as BD's landing gear, and other radially mounted parts. [*]Mechjeb reports the vehicle is under acceleration, even when it's clearly not moving.