This is a thought experiment but not very academic. Assume a satellite solar panel was critically designed in such a way that even 10% increase in mass would result in hinge attachment failure. Assume some inertial frame (A) in a distant planet or space ship, at some part of its course it sees the satellite solar panel is at a relative velocity very close to light speed and when they measure the mass it is twice than that of the designed mass. So, mass measured from earth is design mass 'm'. Mass measured from inertial frame A is '2m'. According to engineers in earth solar panel should work fine, but engineers at inertial frame A would say it should fail. What will happen to solar panel? My answer is solar panel will not fail. Then how physicist in the inertial frame A could explain this.