Thanks all of you for the above. Of course I agree that for aeros a parachute is essential, and a helmet a wise precaution. But all of my Bulldog flying up until now has been non aerobatic, as I get used to the differences between the previous aircraft I have flown and this one. My question was really meant to see if any other new owners of Ex RAF Bulldogs had found a solution to the noisy headsets. When I eventually start to explore Bulldog aerobatic capabilities, I will borrow; a. parachutes, b.bonedomes, and c. an instructor. Parachutes and Instructor are available, but does anyone know where Mk3 or Mk4 RAF helmets can be obtained (with boom mike)other than from Mart Aviation whose website would seem not to cater for those of us with a "Large" head?