It's the issued share capital (all of which is now owned by Alan Mann Aviation Group Ltd) which represents the net figure of book value of helicopters owned less loans, plus cash, debtors and creditors.
However, what we don't know (as the last accounts to be filed were for 30 April 2009) is how much their losses have eaten into that share capital.
It really doesn't tell us anything.
Cheers
Whirls