The company has already told you it can't, the NTUS have checked the figures and say they are right. Why do you think they can ?
Erm...NATS may not have the money in it's account NOW, but there is the small matter of the tens of millions in revenue over the next year and the savings in NOT having to pay interest on loans, exit charges to the spanish, moving of West Drayton etc. You know, the usual day to day costs. I doubt the trustees will say:
Dear NATS,
the fund is £60m short, please pay us £60m by the end of next week.
Lots of love,
The Trustees
PS: Nice cars!
They will come up with a repayment plan in order to bring the scheme up to correct levels.