Talk:Principal axis (mechanics)

Merge proposal
This article is mostly about yaw, pitch and roll, which are already described at yaw, pitch and roll and aircraft principal axis. The prinicipal axes are treated as a subtopic at Moment_of_inertia, which I think is where they belong -- I don't think there's a need for a separate article for the principal axes as opposed to the principal moments. (Also, though this wouldn't be a reason by itself to merge the article, it's a stub with errors -- the principal moments are stationary, not maximal or minimal, and "axis" should be "axes".) So I think this should ultimately become a section redirect to Moment_of_inertia. (I also just redirected spherical top, symmetric top and symmetrical top to that section.) Joriki (talk) 15:31, 4 March 2010 (UTC)
 * Hi Joriki. I have found your merge proposal in the Yaw, pitch and roll page. I would keep separated both articles because the word yaw can be used to refer to an angle or to a rotation around the vertical axis. Notice that when yaw refers to an angle its variation is a precession, not a yaw movement. Therefore it has to be considered a polysemic word and be treated in consequence.


 * About the other proposed merge, Aircraft principal axes, I agree that should be merged here, but with care, because sometimes principal axis means one of the inertia tensor eigenvectors and other times it means a symmetry axis (regardless of the mass distribution).


 * Regards, --Juansempere (talk) 18:39, 5 March 2010 (UTC)

Partial merge done
I have merged Principal axis (mechanics) into Moment of inertia. The first article was only two lines long and I think there is no reason to keep an article like that. The merge was just a copy and paste. The rest of the merge is not so easy and should be discussed first how to do it. --Juansempere (talk) 10:11, 7 March 2010 (UTC)


 * I've tried to merge the text in to Moment of inertia a bit better than cut-and-paste. It looks to me like all of the material from the old article is covered in one of the other three, so as far as I can see the merge is completed. Djr32 (talk) 19:00, 7 March 2010 (UTC)