Re: [Flightgear-devel] radials revisited

[John D. <sf...@av...>]

On 01/29/2007 11:01 PM, Dave Perry wrote:

> This is exactly the situation that John Denker maintained was an
> exception to the rule "report position as the radial from the station
> and DME distance."  This pilot agreed with John.  

Actually I have changed my mind about this.  A couple of days
ago I had the opportunity to ask a couple of TRACON controllers
about this.
  -- They said *all* radials radiate outward.
  -- They said, quote, "The FAA is anal about this."
  -- If the pilot is inbound on the NNN radial, his heading will
   be approximately the reciprocal of NNN.
  -- They said reversing the radial is a rather common pilot mistake.
  -- They said they would not spend air-time correcting a pilot
   over this issue, but they would certainly prefer for everybody
   to use the approved terminology.

I'm sorry if my erroneous discussion of this exceptional case
confused anyone.

As a consequence, we can say that in FlightGear, the --azimuth
command-line option is, without exception, not a radial but rather
the reciprocal of a radial.

> This mistake and
> confused position report was the beginning of a series of mistakes in
> knowing/reporting the position of his AC that 14 minutes later caused
> him to fly into a mountain. 

That's going waaay too far.  Could we please stick to the
facts?

The incorrect utterance occurred at 1104:22.
The crash occurred about 20 minutes later.
The aircraft was in radar contact for four of those 20
minutes, removing any doubt ATC may have had as to the
location of the aircraft.

> caused him to fly into a mountain. 

My little brain is unable to understand how this incorrect
utterance could have "caused" this crash, even in part.

Nowhere in the cited document does the NTSB attribute any
causative role to this incorrect utterance.

In general, not every pilot mistake is part of the chain
of causation.  Similarly, not every controller mistake is
part of the chain of causation.  This is a very, very
important point that commonly comes up in connection with
post-crash litigation.  Everybody blames everybody else
for "causing" the crash, and they often grasp at utterly
irrelevant discrepancies and try to claim a causative
role for them.

In this case, the pilot flew into a mountain because he
failed by a large margin to track the outbound radial.  This
has got nothing to do with what he said about the inbound
radial.

> He was killed.

That's an example of the fallacy of appeal to emotion
  http://en.wikipedia.org/wiki/Appeal_to_emotion