[SystemSafety] MH370

[Matthew Squair]

The really frustrating thing is that a simple and very cheap solution to
this problem was proposed years ago by the inventor of the original black
box and...nothing.

Matthew Squair

MIEAust, CPEng
Mob: +61 488770655
Email; Mattsquair at gmail.com
Web: http://criticaluncertainties.com

On 11 Mar 2014, at 7:25 am, Peter Bernard Ladkin <
ladkin at rvs.uni-bielefeld.de> wrote:

On 10 Mar 2014, at 18:45, Gergely Buday <gbuday at gmail.com> wrote:


http://www.theguardian.com/commentisfree/2014/mar/09/malaysia-airlines-flight-mh370-black-box?CMP=twt_gu


Any expert opinion on that?


Yes.

Some of this is tropes that arose 5 years ago with AF 447 and were then
definitively answered. It is disappointing that a journalist for a major
newspaper is repeating them without taking into account the engineering
answers that were available, and aired, then.

There is a question how far we have come since then, and the article does
mention some development work by Boeing, which I found intriguing but know
nothing further about, despite having asked.

The answer to "my iPhone can do this-and-this; why can't this hi-tech
airplane?" is that your iPhone doesn't have the reliability requirements
that critical data transfer from an airplane has or will have. Quite apart
from the engineering requirements, consider that when a large commercial
transport airplane is lost, there is some EURO 200m-EURO 1bn in play in terms of
compensation. Get the data a bit wrong and somebody is paying out huge
amounts of money that they shouldn't have to pay out, and somebody else is
getting away scot free who should be paying.

The answer to "we send movies over WiFi, why can't we do DFDR data?" is
that (i) we obviously can, but (ii) it has to travel by satellite for
over-ocean flight; (iii) there are lots and lots of airplanes out there
flying - at any one time, two-thirds of the entire fleet is in the air, so
that's lots of data over a comparatively narrow channel; (iv) most of that
data is useless, since the aircraft arrive safely, but it would cost the
airlines oodles of money to send all that useless data, each flight.

The answer to the subsequent question: "why don't we fix all that?" is:
using current protocols, including appropriate error detection, we'd have
to put up more satellites - and of course the industry will pay; that is,
it comes on your ticket, whereas the current setup is free courtesy of the
US military (and, more recently, the EU to whom populations of member
states want to give less money). And for what?

I could check, but off the top of my head we've only had two accidents over
water in the last twenty years in which finding the FDR was difficult: Adam
Air; AF 447 (maybe three, if Malaysia turns out to be difficult, but I
would bet on finding it within a week. An ELT transmits up to 30 days by
requirement, and often longer by happenstance). This is a small, but I
grant not negligible, proportion of over-water losses. TWA 800, SW 111, the
last China Air passenger Boeing 747 were all found relatively easily. Air
India took a lot of work. But *all* were eventually found, including Adam
Air and AF447. So it's purely a question of effort, that is, cost.

So it's worth doing a cost-benefit analysis. Who's done it? No journalist I
know.

But, of course, we don't stand still. The article suggests that Boeing has
been trying to figure out ways of transmitting useful data routinely and
cost-effectively. More power to them, and to those other engineers trying
to make it easier to get useful data from lost airplanes with lost DFDRs.

But, finally, would we be better off, if we got sparse data transmitted by
satellite from a lost airplane at lower cost and then we give up at that
point, rather than actually spending all those resources to find and
retrieve the DFDR with all its data, along with most of the airplane? As an
engineer, I'd say: I don't think so. As an engineer, I want to know What
Went On in all its detail, not just some summary chosen as "enough" by
beancounters. I am very glad the effort was put in in all these cases to
find the wreckage and, along with it, the DFDR. I don't want that not to be
done in future.

PBL

Prof. Peter Bernard Ladkin, University of Bielefeld and Causalis Limited
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