This is pragmatic follow-up part a for episode 11 cause and effect. I'm Ben Alexander and my co-host is John Chichy. Hi, John
Hey Ben. Thanks for that. So I had an excellent
grateful email from gentlemen by the name of Dean Lombard and
one of the great things about
the fact that it was so many people listening to the show is that every now and then you come across somebody who's
Got a lot more
in-depth knowledge and experience about the topics that you're talking about. It just
so happens that Dean is somewhat of a fan of this aircraft, air crash investigations.
He actually has a book. The book itself is called Black Box. There's a link to it in
the show notes. It was published by Harper Collins in 1998 and edited by Malcolm McPherson.
What it is, the full title is The Black Box Cockpit Voice Recorder Accounts of In-Flight
Accidents.
It actually does mention the Aero Peru crash that we mentioned in the cause and effect
main episode.
He's written a very good list of a couple of extra details that I'd like to read out
excerpts from his emails.
He actually sent me two emails on the subject.
So, first of all, regarding the CVR, sorry, CVR is cockpit voice recorder.
So the CVR transcript, he says, is a very harrowing read.
The pilot and co-pilot are completely baffled.
They're getting such contradictory information.
They are getting a stall warning and an overspeed warning at the same time, even though they
were applying the spoilers and had cut the engines back.
the pilots still believed the overspeed warning above the stick shaker stall warning.
Just pausing there for a second, when aircraft are about to stall, in other words, they're
not going fast enough in order to actually stay in the air, they actually drop out of
the air if you go any slower, the sticks literally shake.
That concept was brought in a decade or two earlier.
The idea is that before autopilot was really a thing, pilots would sometimes fall asleep
and they would ease back on the speed of the plane.
It would gradually slow down.
It's about to stall.
The sticks literally then were programmed to shake.
They would shake so that that would wake up the pilot.
That was the whole idea of the stick shaker.
Kind of like rumble strips on the side of the road.
Yeah, exactly.
Exactly.
Good analogy.
Just like that sort of thing.
They're very effective but the problem was in this case, they were getting so much contradicting
information that they ignored the stick shakers of all things, they ignored them
He goes on to say, possibly because of the compelling evidence from the airspeed indicator
Of course, the problem was the airspeed indicator wasn't indicating correctly either
For ages, he goes on to say, for ages they believed they had control problems rather than instrument problems
because their actions weren't reflected by the instrumentation readings
and for a while they had it on autopilot which was of course
was using incorrect data as its parameters.
So the control tower was actually getting altitude data from the plane
and speed data from the radar.
So this is one of the things that people don't realize is that there's actually
a connection between planes and aircraft towers
towers that where the aircraft towers can actually get information from the computers
on board the plane.
They can cross-reference that information against radar readings.
Anyway, long story short, the altimeter was reading 9,700 feet and that's just been confirmed
by air traffic control.
What they were doing was they were comparing the value that they were erroneously getting
from the aircraft rather than from the radar, which meant that they were essentially reading
back the value that they saw.
Yeah, we confirm. They didn't realize that I was simply telling the airplane back, "Yes, and we actually have you at the wrong altitude."
We really don't know because we didn't really check anything.
Yeah, could the story get any more awful?
Yeah, it's awful, just absolutely awful. See, all these things added up. It's crazy, terrible.
Anyway, the overspeed warning, he continues, "The overspeed warning was still sounding along with too low terrain."
terrain.
If you watch the reenactment in, I think it was the air crash investigation, and in the
reenactment when they're reading that part of the CVR transcript, you heard the alarm
going off, "Too low, terrain.
Too low, terrain.
Too low, terrain."
These pilots are trying to figure out what the hell is going on.
They can't see anything, and of course, at which point, they hit the water at 300 miles
an hour and it's all over.
I have to say a very big thank you to Dean for that and he had a lot more of that information
for me and it was great to get that feedback from someone who was into that and also has
an interest in it.
I haven't gone so far as to buy the book but honestly, if you are interested in this sort
of thing, then there are books out there, not just this particular one, there's several
of them and I think a lot of them are done by the same guy, Malcolm McPherson, I think
has had several books, I believe, on the subject.
I think that's an interesting addendum to the episode.
Thank you very much for that feedback and that was all I had.
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