From: Cynic on 23 Dec 2009 16:49
On Wed, 23 Dec 2009 19:39:08 -0000, Conor <conor(a)gmx.co.uk> wrote:
>> Most aircraft complete a trans-Atlantic crossing without suffering an
>> engine failure. Therefore I assume that you would be just as happy to
>> fly across the Atlantic in a single engine aircraft as in a
>> multi-engine aircraft?
>Can't see why not. In fact the argument could be made that there's less
>to go wrong.
The argument you put forward is often cited *as a joke* amongst people
in the field. The usual statement is, "Four engines are far less safe
than one engine, because there is four times the probability that you
will have an engine failure."
I really didn't think there were people who would actually take such
an argument seriously. Maybe you should think it through a tad more
deeply. The clue is in the fact that a muti-engine aircraft can
*continue to fly* in the event of an engine failure.
I hope you have never had occasion to design a safety critical system.
From: Conor on 23 Dec 2009 16:55
In article <vf35j51aqa4hif4v3hfl0104hhlkp4okri(a)4ax.com>, Cynic says...
> I really didn't think there were people who would actually take such
> an argument seriously. Maybe you should think it through a tad more
> deeply. The clue is in the fact that a muti-engine aircraft can
> *continue to fly* in the event of an engine failure.
And amazingly, single engine aircraft manage to continue on in the event
of an engine failure. And as single engine aircraft form a large part of
military fighters, still pass CAA safety tests and aren't dropping out
of the sky all over the place, I'll continue to assume that on the
whole, they're safe.
OTOH, in the last couple of years, entire fleets of multi-engined jets
have been grounded because of a fault in the engine control system.
> I hope you have never had occasion to design a safety critical system.
I hope you don't. By the time you've finished, the item will be such a
behemoth due to the "must cover every eventuality" myriad of safety
systems that it'll be completely unusable.
I'm not prejudiced. I hate everybody equally.
From: Denis McMahon on 23 Dec 2009 21:40
> In what circumstances do _you_ think an alert and attentive driver can
> head blithely towards a low bridge in a vehicle that was almost certainly
> visibly tall when they got into it - without even the slightest
> expectation of "issues" crossing their alert and attentive mind...?
It's quite obvious that, of the many things that were clamouring for the
driver's attention including making a right turn across the dual
carriageway, checking his route on his satnav (and it probably wouldn't
have been any less distracting if he'd been using either a map or
printed up directions), and looking at the road ahead, he either:
a) didn't look up and see the low height warning; or
b) saw the low height warning but didn't realise the significance of it.
The latter might be explained by the fact that his normal bus route(s)
doesn't have bridges that are too low and may not even have any bridges,
and so he does not habitually think when approaching a bridge "is the
clearance more than the vehicle height?"
Normally a bus driver is trained on a route, and normally routes are
planned by people who take things like bridge clearances into account
when specifying double deckers. The driver was probably outside his
comfort zone to start with, driving a trip to another city without any
proper route planning.
Ultimately the responsibility is with the driver, but I still think it's
worthwhile to look at all the causal factors and consider, for each
identified factor that contributed to the collision, how that factor
might be mitigated.
Maybe double decker buses must not be used for off-route school trips.
From: Adrian on 24 Dec 2009 04:15
Denis McMahon <denis.m.f.mcmahon(a)gmail.com> gurgled happily, sounding much
like they were saying:
> It's quite obvious that, of the many things that were clamouring for the
> driver's attention including making a right turn across the dual
> carriageway, checking his route on his satnav (and it probably wouldn't
> have been any less distracting if he'd been using either a map or
> printed up directions), and looking at the road ahead, he either:
> a) didn't look up and see the low height warning;
Or, even, the approaching bridge
> or b) saw the low height warning but didn't realise the significance of
You mean he forgot he was driving a double-decker bus?
> Maybe double decker buses must not be used for off-route school trips.
Maybe idiots shouldn't be used as bus drivers?
From: Cynic on 24 Dec 2009 05:28
On 23 Dec 2009 21:41:50 GMT, Adrian <toomany2cvs(a)gmail.com> wrote:
>> Do you feel that we should not take precautions to mitigate the effects
>> of driver incompetance?
>Absolutely we should.
>Sack incompetent current bus drivers, and make sure incompetent potential
>drivers do not pass the PSV driving test in future.
You appear to believe that it is possible to select perfect drivers
who will never make mistakes rather than accepting that mistakes are
inevitable and attempting to reduce the consequences of such mistakes.
Your approach is doomed to fail.