G109.
I roughly worked out the NET take home pay for a year 1 FO including allowances to be 4830 GBP per month.
does that sound about right?
This sounds a little high to me, while junior the allowances make up a much larger chunk of your pay than for those more senior. The allowances fluctuate quite a lot depending on night stops vs day trips vs reserve, little of which you have much control over while junior.
I'm still in my first 5 years and after the compulsory pension contributions are deducted my Gross pay is usually between 5500 and 6000 GBP. Then you need to deduct tax, NI and any expense payments. I would therefore work on the low 4000's GBP and then be happy when you have a busy month.
Regards