[1.187] Ship weight glitch when detaching block from other grid (atmo lander)

Hi,

I discovered this when salvaging the batteries from the atmospheric lander. What I did was basically:

- cut away blocks below battery on lander (but so that it is still attached to the lander)

- added a merge block below the battery

- flew atop the battery with my small atmospheric ship

- lowered until landing gear touches battery and locked landing gear

- cut away the supporting blocks around battery + merge block so that the battery block is now only held by the landing gear of the small ship and can thus be transported over to the station (on a planet) where it is joined with another merge block. Voilà, battery saved.

The problem: as soon as I cut the battery + merge block free from the atmo lander, the small ship carrying both of them begins to sink slowly, as if it could not carry the weight of both blocks. If I set both blocks down and quickly disengage the landing gear lock and engage again (quickly, so that the battery plus merge block do not slide away), the ship can float in mid air without a problem while carrying both blocks with the landing gear.

What seems to happen is that as soon as the blocks are cut loose from the atmo lander, they get added to the ship weight but not to the calculations of the inertia dampers and thus the ship sinks. If detached and reattached to the landing gear, the calculations are corrected.

I think this should be fairly reproducible.