A couple of years ago a BAA yellow opspatrol (similar model to this accident) vehicle rolled over onto its Heathrow’s ‘F’ ‘B’ ‘R’ taxiway area, no other vehicles involved. Apparently the BAA’s response was “there was a bee in the vehicle causing the driver to loose control”.... the speed it would take to roll a vehicle on a wide taxiway is significant. You only had to sit and watch out the window how fast these BAA vehicles go, airfield ops is not an emergency needing to drive that fast, they’d need to invest in more resources if they’re thinly spread.....On a personal note I got “caught” speeding at LGW airside, 30mph (20mph limit the whole of LGW main roads) on a clear sunny day driving behind empty remote stands with not another vehicle in sight. The yellow peril was probably travelling IRO 70mph with black smoke pouring out across the taxiway to issue my bollocking on the grounds of health and safety..... this sort of incident at LHR could have been predicted by many a LHR airside worker. RIP John Coles.