On Mon, 04 Sep 2006 11:29:17 -0400, Bob Noel
wrote in
:

In article ,
Larry Dighera wrote:

Do any of those displays have the software at DO-178B Level C or higher?
(btw - I do know a little about the avidyne display)

I am very apprehensive about Avidyne avionics. What can you say about
their products?


I can say that Avidyne was the first company to get a windows-based product
certified to a 178B level that would ordinarily be level C.

Just so we are all aware of the definition of DO-178B software levels:

http://en.wikipedia.org/wiki/DO-178B
Software level
-------------

The required level is determined from the safety assessment
process and hazard analysis by examining the effects of a failure
condition in the system. The failure conditions are categorized by
their effects on the aircraft, crew, and passengers.

Catastrophic [Level A] - Failure may cause a crash.

Hazardous [Level B] - Failure has a large negative impact on
safety or performance, or reduces the ability of the crew to
operate the plane due to physical distress or a higher workload,
or causes serious or fatal injuries among the passengers.

Major [Level C] - Failure is significant, but has a lesser impact
that a Hazardous failure (for example, leads to passenger
discomfort rather than injuries).

Minor [Level D] - Failure is noticeable, but has a lesser impact
than a Major failure (for example, causing passenger inconvenience
or a routine flight plan change)

No Effect [Level E] - Failure has no impact on safety, aircraft
operation, or crew workload.

The number of objectives to be satisfied (with independence) is
determined by the software level.

Level Failure condition Objectives With independence
----------------------------------------------------------
A Catastrophic 66 25
B Hazardous 65 14
C Major 57 2
D Minor 28 2
E No effect 0 0


Note that the windows portion of the software does NOT comply with
Level C objectives.

I presume that Windows does not comply with Level B either.

And how, pray tell, can avionics that run an OS incapable of meeting
the specification be citified to it?

But last I knew, Avidyne consider the technique(s) used [to meet DO-178B] to be
proprietary. (I don't [know] what they are, but I have some educated guesses
on possible methods).

Would those methods include mordita?*

I've seen some demos of their products, which look way cool, but they are
also way too expensive for me.

But are Avidyne products that employ Windows OS reliable enough to
preclude their negatively impacting air safety?

Not much help - I know...

You know more about the subject than me. Thanks for your input.


* http://www.sandiegomag.com/forums/av...cptnmord.shtml