Vacuum flask on-board plane

[Yodel]

Does anyone know if you're allowed to take a vacuum flask on board a plane (in the cabin or the hold)?

[markja]

yodel, don't do it!!! air presure is different on a plane compared to the ground. the flask may go bang or when you open it the contents go splodge and fly out! holds on planes may not be presurised, so high in the sky your suitcase may develope a case of leaky flask and liberaly cover the contents in tea,coffee, what were you going to put in? (if the lid is off then that's a different matter)

[Yodel]

Thanks. I don't thing I'll bother!