On Nov 17, 5:05*pm, "PCool" wrote:
"Don Johnstone" ha scritto nel et...

At 03:18 17 November 2010, Paul Remde wrote:
Well done.

The first is that the use of STEALTH mode degrades the performance of an
instrument which is designed to enhance flight safety. While it is fine
for an individual pilot to make a decision to do that I am extremely
uncomfortable with requiring someone to degrade a unit and therefore
safety. I am pretty sure that even a British court would take a very dim
view of that were there to be an accident. Whether a court would find me
personally liable I have no way of knowing and given the only way of
finding out I prefer to remain ignorant.

Paulo explains this is not correct below. In the case of powerFlarm
some of that data normally shown on a PDA is shown on the display and
that is also dithered in the same way (or it would make no sense- and
the Flarm folks are not stupid). One observation is there also seems
to be lots of confusion about Stealth, Contest, Nearest and Collision
modes. The best thing to do there is to read the operation manual for
a current Flarm unit on Flarm's website (http://www.flarm.com/support/
index_en.html) and see their guide for contests as well.

No, FLARM units are always transmitting correct position each other. Only
the PDA output is degraded.
But if you are close each other, output is no more degraded concerning
nearby traffic. It is well thought.

The other concern is that the requirement is un-enforcable. FLARM is an
open technology and while it is possible to check an instrument installed
in the glider it is not possible to check and undeclared FLARM unit
carried by the pilot, searching pilots before they get into their glider
is not likely to ever be acceptable. It is comparatively easy to have a
non--stealth unit available. A rule that cannot be enforced should never
be made.

And that undeclared non-stealth unit would be visible to and recorded
by nearby Flarm units. So one possibility is just the risk of
detection would be enough to prevent carrying one. We do not strip
search pilots today at contests so I am not sure enforcement like that
would ever be needed. But again it is a non issue now as the rules
seem to be let's just see how things go without any stealth
requirement. And all this is a concern about something we just do not
have to face at the moment.

The major problem with all this is there is really nothing to complain
about :-) The USA rules commitee has actually looked at the issues,
looked at the technology coming in PowerFLARM and actually made a very
sensible decision given where we are and they took the time to explain
their thoughts. Thanks guys.

Flarm is not open technology. It is proprietary technology, and no company
except FLARM in switzerland can do it.
All other companies on the market bought licences from flarm. *No US company
will be allowed to market its own traffic advisor,
unless they buy it from flarm. It is called monopoly , and in this case it
is about *your safety.
A couple of years ago, the IGC had decided to adopt a public protocol for
traffic informations, but nothing happened so far.

paolo

Related muddled thinking around UAT technology by the SSA has probably
helped Flarm feel less than excited about entering the USA market.
Luckily PowerFLARM is not too far away...

Darryl