A longhaul captain earns 25% more gross than a longhaul copilot at the same pay point. Obviously he'll pay more tax so the take home will likely be just over 20% more. Can't say exactly without knowing which pay point but the earliest a new entrant will see a longhaul command is pp20 or thereabouts. At current rates, take home would be in the ballpark of £7k per month for 900 hours per year.