Exnomad, it seems that you are owed a rather belated welcome to the thread. Belated because I see that you have posted here once before at least but no such welcome resulted, sorry about that.
Here we have that ideal situation whereby your brother ticked all the OP boxes for WWII pilot brevet and you, his younger brother, followed in his footsteps albeit as post war nav. Hopefully you can tell us his story and then yours, thus bridging that vital but often overlooked post war transition to the later RAF that most of us inhabited.
No doubt Danny will be along soon enough to do the honours re a reserved comfortable though shabby armchair next to the stove. So make yourself comfortable and settled. Tea, milk, any sugars? When you are ready then, we are all ears.
Oh, you can't dot enough i's and cross too many t's. It's all the 'by the ways' that are the most interesting. Over to you then, Sir.