>
> Hello Paul.
> I was off the list when this happened. Would you be able to send
> one of the notes that announced details of the accident?
> Thanks
> Peter
>
> My agreement with the FAA when they allowed me to examine the wreckage
> and the crash site was not to publish the details. Sorry. I wish to
> maintain that relationship in the future. However I will be glad to
> review
> anyones new design for a fuel system based on what I learned from
> that investigation.
>
> Paul Lamar
>


Hi Paul,

While I respect that you have an agreement with the FAA that you have to
keep, it seems a shame to keep the data under wraps.  Out of curiosity,
what was the FAA's end of the commitment.  Do they have any
responsibility to report the accident findings in a complete and useful
way?  Also, if you found that the crash was caused by something in the
installation that you HAVEN'T already been preaching, how will you be
able
to integrate the new information without breeching the agreement?  I
would
like to be able to learn something from the accidents of others.


Regards,

Matt-

Yes they do have a commitment. The NTSB will eventually file
a final report to:

http://www.ntsb.gov/ntsb/Month.asp

Be assured if the subject of a fuel system comes up and I see something
that based on my 45 years of engineering experience that I think won't
work I will let everybody know about it :)

There are two fundamental things you need to know about fuel systems.
The pressure at any point in the system under all scenarios.
The temperature of the fuel under all scenarios.

The pressure is due to several factors. Head, which is the pressure
due to the weight of the fuel times the G load and air pressure caused by
the vents. An improperly designed vent system can empty a tank
in short order due to aerodynamic pressure alone.

The fuel temperature must be kept below the boiling point or
vapor lock will occur. Pressure affects the boiling point of fuel
just as it affects the boiling point of coolant in a cooling system.
A low pressure on the inlet side of a pump can cause the fuel
to boil at a lower temperature than you might think.

As one can see new fuel systems are more subtle and complicated than one
might otherwise imagine. They must be carefully and fully thought out.

Start by writing down every scenario (G load, aircraft attitude, etc.)
that you can imagine.

List expected pressure and temperatures under each scenario.

Paul Lamar

In the past, Paul, you indicated that you could/would share your
conclusions after the FAA/NTSB had published their report.  I note that
your current writings seem to move away from this - is this the case, or
am I reading too much into what you've posted lately?

Mark