"Mark James Boyd" wrote in message
news:412a892d$1@darkstar...

The Cezznas have this technology for the side doors, and it is a cause
of occasional failure.

There seems to be a philosophical and legal issue: if it is a stone-cold
simple "pilot must move it to open or close" then it is obviously the
pilot's fault if it isn't closed. If it slightly more complex,
self-latching and it fails, the manufacturer is sued. So manufacturers
would have to make self-latching canopy latches that are simply
IMPOSSIBLE to fail.

NOTHING is impossible to fail, especially the silly canopy latches we have
today.

This is actually very, very challenging...

Why?

The other issue is what if they fail to open when someone wants
to eject?

Simple design excercise, I can think of at least two ways of doing it right
now.

Or what if one can convince 12 senior citizens that
this might have happened?

You could just as easily convince those same 12 white-hairs that this simple
100-year-old technology could have prevented an accident if it were incorporated
into the design of a crashed glider.

Springs get debris in them or fail, latches and cams repeatedly
rubbed eventually wear, etc.

Sorry, don't agree. The latches we have now fail. Even the self-latching
canopy lock (as in the L-13) must be checked before flight (and should be a
checklist item) the difference is that its NORMAL CONDITION IS SAFE. If you
forget to check it, 99.999% of the time it won't kill you. What can be bad
about that?

From a manufacturers standpoint,
self-latching canopies are a no-no. I don't think we'll ever see
them in manufacture by any company that can ever be sued...

By your logic, how did we ever get manufacturers to design self-connecting
control hookups? (which also should be a checklist item before flight)

Vaughn


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Mark Boyd
Avenal, California, USA