ORIGINAL: RCFlyerGuy
Hi,
I wondering if anyone out there has a fairly scientific way of measuring a gas or glow engine's power output, other than relying on what any particular manufacturer claims their engine will produce.
Short of having an expensive dyno setup, I've thought about fabricating an engine test stand where the engine mounts on rails that slide in a track, so that the amount of thrust produced could be measured as the engine pulled against let's say a strain gauge. It could even be something as crude as a common fish-scale to start off with, but I think that's a no-nonsense way of evaluating what an engine can actually produce.
Any thoughts?[sm=spinnyeyes.gif]
If you used a strain gage, possibly set up as a load cell you would still need to calibrate it. This may be more accurate than a fishscale, but not enough to make a difference. If you used the strain gage to just measure pure micro-strain you would still need to convert this to pounds of thrust, which would still require a calibration of your fixture. Then the question is, how would you accurately calibrate it.
I used to worry about manufacturers posted horse power, but now I don't care what they post. There is enough information on forums like this to get a good idea about almost all the engines out there. There are so many factors that could affect your testing that I'm not sure how useful it would be compared to the information we already have on forums like this. Also how a engine performs on a test-stand and in the air will probably be completely different. My opinion is to let a dead horse lie.