BOI into the 2012 Tornado Collision over the Moray Firth

[Distant Voice]

Just noticed a note at the bottom of the "Hazard Data Criteria" page associated with Nimrod. The information comes from BP1201, which was the document used prior to the new MAA regs, and referred to in a letter, dated 11th Feb 2011, by AVM Bagwell (AOC No.1 Group). The note reads "The Baseline Safety Case generally employs only qualitative probabilities in risk assessment". Unfortunety, AVMs Bagwell and Atha appear to have gone down the "numbers" route in order to justify their Tolerable and ALARP statements. Numbers that were provide in a report by QinetiQ, and a report that MoD is having problems locating.

In addition they, with the aid of the new MAA regs, have been able to downgrade the frequency of the risk from OCCASIONAL to REMOTE. The original definition for OCCASIONAL was, "Likely to occur during the operational life of a particular fleet", and for REMOTE, "Unlikely to occur at all during the operational life of a particular fleet". We now have in the new regs, OCCASIONAL - "Likely to occur one or more times per year", and REMOTE - "Likely to occur one or more times in 10 years". So what was OCCASIONAL (or even PROBABLE) is now REMOTE. However, what is important is what was the true risk on the lead-up to the accident, and at the time that Bagwell and Atha signed off in 2011, it was OCCASIONAL (and CATASTROPHIC) which makes it an INTOLERABLE risk. I put the frequenct as being OCCASIONAL because between 1984 and 2009 the fleet was involved in a total of 9 mid-air collision accidents.

Normally, a combination of risk frequecy and severity determines the risk index; Broadly Acceptable, Tolerable, Undesirable or Intolerable, but this is no longer applied. Instead we compare the mathematial probabilty of a risk of death with a 1 in 1000 figure from an HSE document. A figure which is based on industry where people are exposed to a risk for some 2000 hours per year not 212 hours (Tornado aircrew), and a figure which the HSE have stated does not cover a flying environment.

If this is an example of self regulation then it is time to think again.

DV