Have it on the QT that not an Air Force instigated c**k up....look towards the Really Large Corp.... However, should have been caught in other areas of the fuels QA system!
Indeed. Check blend then refractometer check before commencing full blending operation was the standard procedure I was trained to do and practiced when carrying such tasks.
Then again, if it was Rejects Last Chance who were performing the blending operation its quite possible the "all fuel is the same isn't it?" attitude that I saw displayed on so many occassions by the RLC may still be an issue or just the fact they haven't been trained or were cutting corners.
No doubt someone at West Moors is currently either scratching their head over how to remove the anti-freeze or is punching number to work out just how much 'clean' fuel would need to be added in order to blend the lot within Def-Stan limits, if a dilution blend is even possible for anti-freeze (I've never heard of a major anti-freeze contaimnation like this, not even sure if it can be blended out).
As for the contaimination being caught elsewhere, it depends upon the overall ratio of anti-freeze to avtur (which if the blending rig was set up correctly would have been blending 1-800, if my memory is correct) and its effect on the SG of the blended product. Refractometer tests are not a standard 'point of issue' test, rather they are performed only daily on the bulk stock and, as mentioned, during the actual blending process. Yes a daily check should have caught it (which it perhaps eventually did) but if the fuel were issued forward without being subject to the required settling embargo then retest this could be how it slipped through the net.
Having had to 'clean-up' mistakes by the RLC in the past with regards fuel contaimination (especially a very serious one that caused the quarantine of all bowsers and blended fuel stocks at the UKs only Mediterranean staging point) I wouldn't be surprised if it was them dropping the ball but then again, I've had to sort out mistakes by Suppliers before too.