Woodford is closing because it has no work. The world is awash with military Aero faciliites that have no work and are closing. The Peace Dividend.
Defence spend is nugatory; its sole justification is that you never can tell who, next week, will be your friend, and who not. All UK Govts. since 1945 have all spent to be better safe than sorry - Attlee's (when until April,1948 UK had no enemy), Macmillan's (Sandys), Wilson's (Healey), Blair/Brown, and in last year's Review, Cameron's. If its currency is convertible at market, a State has a limit on men/material/money that can be diverted from civil-earning. Gibbon's view of the Decline and Fall of the Roman Empire was that number is 1%. Japan's prosperity, 1951-into the Nineties, was in part due to holding Defence at 1% of GDP, while UK touched (briefly) 10%. We now hover >2%, and have a presence on, below, and above the waves. It is proper to ask "why", and to query SSBN, Main Battle Tank, indeed anything beyond a Rapid Deployment contribution to a Coalition. If a Party taxes us to buy military kit in excess of a consensus need (today, it seems: 1xsolo, Falklands-style; plus 1xCoalition, ex-Yugo-style), that Party will not govern long.
"Touch labour" for civil aircraft, just as for every other volume product, is cheaper in warmer climes than in Manchester. It's not cheap labour, it's all the factors of production - China can dig up bauxite, and generate energy into its factories in its own currency, such that all $ earned from exported products can be presented as net benefit.
BAE, like, say Daimler, designs/markets/product supports in its Centres of Excellence, buys tin and boxes at market, and assembles where/how the market dictates. It carves out niches, such as making bits of Boeing wings.
Like posters here, every site, every sector has a life-cycle. Making military aeroplanes is in the decline phase. The wonder is not that Woodford is about to take up non-Aero duties, but that it endured so long.