The pay at Ryanair varies between bases and whether you are based in the UK or Europe and what contract you're on. For a captain directly employed on a UK contract £6k in a month is definitely possible, however they are listing their 'best' month (probably in the summer). Take home can range from £5k to £6.5k depending on if you have flown more than 100 hours in that calendar month, worked any days off etc. Average over the year I would say it is closer to £5.5.
True. It varies.
Mine was an average of almost exactly £5,900 for 825 hours. Minimum £4,600 on a month off and maximum £6,600 on a busy month in the winter.
The trouble with calculating wages by looking only at take home is that the tax regime in the UK means that for every extra £10k you earn when you're on less than £100k you only get an extra £500 per month in your pocket. Once you get above £100k, it's awful, as you only earn £250 extra per month per £10k*.
*The HMRC tax calculator tool.