Here goes nothing....
Leander,
A "back of the fag packet" calculation shows that BA generates about £100 - £120m of cash per year AFTER paying interest and average reinvestment in assets
From this BA has the "choice" of
Pay off some debt, which it does need to do for long term survival
Pay a dividend
Pay towards the deficit
So, in true accountant fashion, the answer is it depends!
If you use all the surplus for the pension,the debt will stay and a £200m interest bill will stay with it. A small downturn could then cripple the company
To do all these BA would need to generate about £400m per year (My guess not BA figures)