Help needed..

Not sure if anyone can help me with this one, but i would like to find some information on a grandfather that i never knew.

The story is that he was my fathers real dad, but he left my grandmother when my father was about five years old. She subsequently met and married a soldier who became my fathers stepdad, and my step grandfather. Still with me.?
Anyway his name was Bernard Wheatley, and i understand that he was a flying instructor in the RAF during WW2. He spent some of his time in the Taunton area of Somerset and i believe died there in the 1990’s, literally just weeks before my brother managed to track down his last address (sods law).
His wife at the time of his death was very reluctant to divulge any info to my brother, possibly fearing some sort of claim to any inheritance.

I’m afraid thats all i have to go on but i would appreciate any advice or guidance that you guys can point me in the direction of.

Rob.