There are occasions when the requirements change, not just the risk
tolerance, e.g. for a fast jet or helicopter response to failure of a
terrain-referenced navigation system in peace is to "pop up" to a safe
height. In war time, it is not (as you will be shot down with high
probability.

John McDermid
+44 1904  432726
+44 7802 234814


-----Original Message-----
From: Tariq Mahmood [mailto:mahmood.tariq@xxxxxx] 
Sent: 19 December 2006 10:20
To: safety-critical@xxxxxx
Subject: Re: [sc] Safety in Conflict/Wartime

I suppose we should explore the questions behind the question to begin with.

What are, if any, the unique features of a wartime situation which
influence safety?

In other words, does requirement for safety, as a condition, change
between war and peace situations or is it just our tolerance that
changes? Is there a dispute between two goals of a system that only
arises in a war situation?

An example could be that a system consisting of a battleship and a
carrier might be considered safe if the battleship takes a hit to
protect the carrier in a war situation. Who makes such decisions and
at what point in the development should such decisions be enforced?

If there exists such a change in 'reasonable' level of safety between
peace and wartime, then the brute force approach would be to consider
all the permutations, as pointed out by Graham. One would have to
first identify tradeoffs and disputes beforehand and then establish
mechanisms for making the decisions when such disputes arise.

Following this, a metric would then need to demonstrate the impact of
such decisions on safety as well as the other system goals such as
military objectives. It would then boil down to what we can measure
and how that relates to our safety and other goals; and that is a
matter of perspective of the decision makers.

Finally, assuming now that the levels of acceptable safety change,
then would it be sufficient to build a system with the most stringent
of those safety levels and thus ensure a reasonable level of safety
regardless of a war or peace situation?

Nothing concrete, but hopefully we can generate some discussion on
this interesting domain of adaptive safety.

-- 
Tariq Mahmood
Dept. of Computer Science and Software Engineering
The University of Melbourne
Victoria 3010
Australia

Tel: +61 3 8344 1424
Fax: +61 3 9384 1184
Web: http://www.cs.mu.oz.au/~tmahmood/

On 12/19/06, Hopwood, Tony (UK) <Tony.Hopwood@xxxxxx> wrote:
>
> Dariusz,
>
> What are "battle shorts"?
>
>         Tony
>
> -----Original Message-----
> From: safety-critical-request@xxxxxx
> [mailto:safety-critical-request@xxxxxx] On Behalf Of Walter,
> Dariusz (AUS BAeA)
> Sent: 19 December 2006 03:51
> To: safety-critical@xxxxxx
> Subject: RE: [sc] Safety in Conflict/Wartime
>
>                *** WARNING ***
>
> This mail has originated outside your organization, either from an
> external partner or the Global Internet.
>      Keep this in mind if you answer this message.
>
> I would imagine that in a conflict situation the scales tend to tip
> towards mission success in the mission-criticality vs safety trade-off.
>
> This would be handled well in a risk based framework. A greater safety
> risk may become acceptable, and enabled via, say "battle shorts".
> Ideally there would be some preconceived model that would indicate the
> improvement in mission success versus the increase in safety risk.
>
> Unfortunately no direct references, I'm afraid.
>
> Dariusz
>
> -----Original Message-----
> From: safety-critical-request@xxxxxx
> [mailto:safety-critical-request@xxxxxx] On Behalf Of WHITE Tracy
> Sent: Tuesday, 19 December 2006 12:13 PM
> To: safety-critical@xxxxxx
> Subject: [sc] Safety in Conflict/Wartime
>
> I am trying to compile a paper which raises the question of what is a
> 'reasonable' level of safety in a conflict situation, specifically what
> level of measure we might apply. I recall from the past that this may
> have been attempted in a defence standard, but fizzled out as being too
> difficult. Can anybody point me to any articles or consideration which
> may have been published on this subject, or may assist in coming up with
> a measurably 'reasonable' approach to the problem
>
> I would appreciate any help/advice offered.
>
> Regards
>
> Tracy White <mailto:Tracy.WHITE@xxxxxx>
>
>   _____
>
> System Safety Lead Engineer
> Aerospace Division
>
> Tenix Defence <http://www.tenix.com/>
>
> Ph: 08 8259 3125
> Fax: 08 8255 5174
> Mob: 0431 405 394
> Email: Tracy.WHITE@xxxxxx
>
>
>
>
>
> Disclaimer :
> The contents of this e-mail including any attachments are intended only
> for the person or entity to which this e-mail is addressed.  If you are
> not, or believe you may not be, the intended recipient, please advise
> the sender immediately by return e-mail, delete this e-mail and destroy
> any copies.
> Tenix does not warrant nor guarantee that this email communication is
> free from errors, virus, interception or interference.
>
>
>
>
> ********************************************************************
> This email and any attachments are confidential to the intended
> recipient and may also be privileged. If you are not the intended
> recipient please delete it from your system and notify the sender.
> You should not copy it or use it for any purpose nor disclose or
> distribute its contents to any other person.
> ********************************************************************
>
>
>