The Math Forum web site has a lot of useful formulae in the FAQ section.
This link is for ellipsoids:
http://www.mathforum.org/dr.math/faq/formulas/faq.ellipsoid.html
Scott C Grove
Senior Support Engineer
Babcock Design & Technology
[bigears] Can anyone advise me no the factor of safety I should be using on temporary Lifting eyes on steel modules designed to BS 5950 which require to be lifted into place using either a mobile or tower crane?
Normally I would design lifting eyes with the safe working load as a factor of 4...