Dick
Hi, my name is Jock Hay and I served at Raf Coningsby on 29(F)Sqn at the time you were there, I do remember the Hush House being stripped out and the trials which were undertaken at that time.
In relation to your reference to the White Swan, which was the pub I used as my local, this was the first public house in Coningsby village that you would pass on your left as you left the base and arrived in the village. To my knowledge it has no historical link to 617 Sqn, but I strongly suspect that the bar you are referring to is the Lancaster Lounge which is situated within the Petwood Hotel just a few miles away from Coningsby in Woodhall Spa; this hotel was used as the 617 Sqn Officers Mess during WW2. I think you will find the information and photographs you are looking for at this site www.petwood.co.uk/history.phtml
I hope this information is of use to you. Good luck with your writing.
Regards
John(Jock)Hay