Tom,. .. .I too suffer from Right bundle branch block with left axis deviation. I joined RN 12 years ago and it was discovered in initial medical for aircrew. After investigation it was cleared, but I only found out about the condition some eight years later when sitting medical for RN divers course. So doctors were obviously not too concerned!. .. .After leaving the RN for civil ATCO, I was initially refused a class one medical on the grounds of this condition, and had to give proof of pre-exisiting condition (records from the Navy from original application) and undergo a 24hr tape test (records the heart via a small box attached by belt to waist). Unfortunately my medical records were incomplete, so in the end did not form part of the final analysis - thanks RN.. .. .I am relativley short, but with a muscular build and am a marathon runner. Despite my obvious fitness, the CAA needed these further tests to cover their own backs - if I keel over in ten years time and it results in an incident, they can at least prove that the condition was thourougly checked.. .. .It was a lengthy process - SRG would not at first refer me to a local doctor for the test, and he in turn would not arrange the test at a local hospital without the referral! The test itself was simple - you carry out your normal daily functions, but I had a day off work, so spent most of it in a state of rest - it may or may not have helped as the condition is always present, but I was of the opinion 'anything that might help has to be tried'!. .. .I was forunate that my fees were paid as I was employed by my present company - on condition that I passed the medical - but if you have to go through this process and pay yourself, expect to pay in the region of £240 for the extra tests (current as of Jan 2002).. .. .Good luck with it all!. . . . <small>[ 05 March 2002, 14:18: Message edited by: Go for 5, Get 3 ]</small>