Haddon-Cave, Airworthiness, Sea King et al (merged)

[JFZ90]

I could be mistaken, but I think there still remains much confusion over ALARP.

My opinion is as follows:

When HC talks about no such thing as "tolerably safe but not ALARP" he mentions the fact that the time aspect of the R has been misunderstood. This is consistent with many comments at the time made on here, e.g. in relation to TWA800.

My theory (only guessing here but seems to me the best fit):

It has been suggested that the original QinetiQ report did not mention tolerably safe and only said it was not (yet) ALARP. They probably stated this on the basis that the you could spend relatively little money to address some further residual safety risk (i.e. replacing seals). The report did not make it clear however that from a risk perspective it was reasonable to take x months to conduct this further risk reduction and continue flying - i.e. they thought it was tolerably safe. Hence it was flawed to state that it wasn't ALARP - it should have stated it was tolerably safe but a timely seal replacement programme should be implemented to address residual risk. This would be more consistent with established procedure - i.e. similar to post TWA800 Airworthiness directives where airlines were given years to rectify safety risks over a "reasonable" timeframe (hence this was ALARP decision making).

Hence, if the IPT asked for "tolerably safe" to be included* (i.e. properly reflected) then they were in fact just trying to get QinetiQ to write their report properly. It appears that they didn't do this right as when they added "tolerably safe" they didn't properly use the word ALARP or put it in the right context which has created no end of problems and misunderstandings.

I seem to recall Mick Smith used the QQ report wording of ALARP to imply SofS had lied to the house many months ago - looking now at the likelihood that the report should have said "tolerably safe" and not mentioned "not ALARP" (which was false as stated by HC), it can be seen that he wasn't actually lying. It can be seen however why the HC report criticises QQ for not understanding the term, and he mentions how this has created much confusion (I suspect this is a direct reference to Micks article).

PS I am not defending MoD here (I found HC gripping and alarming in equal measure) - just trying to put what is in my opinion the correct interpretation on the ALARP issue.


*don't know if this is true, just assuming that the accusation that they did is true for a minute which I know is dangerous!