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From: Gary Casey <glcasey@adelphia.net>
Subject: Safety improvements

The recent discussion about safety improvements that could come about  
from pilot "improvements" is certainly appropriate.  I'm far from an  
expert on that subject, but on the subject of improving the potential  
safety of the aircraft I do have some opinions from an engineering  
perspective as this is where Lancair could have some positive  
impact.  Following are some of my observations:

1.  Trim authority - some or all of the trim servos seem to have  
significantly more travel than is necessary, especially nose-down on  
the elevator.  This has been widely discussed on the ES list, and I  
assume it pertains to other models as well.  Nearly full-up trim is  
required for landing with a forward CG, but very little nose-down  
trim is required for high-speed flight.  The trim system was designed  
to be nearly symmetrical, creating a large amount of available excess  
travel in that direction.  This travel should be limited by reducing  
the servo travel.

2.  Fuel vent redundancy - there is no redundancy built in.  I was  
tempted to drill a small hole in the vent tube inside the wingtip to  
provide venting if the external vent became plugged, but didn't  
because of the concern about having fuel vapor inside the wing.  As  
far as I know, certified aircraft are required to have some kind of  
redundant vent.  I'd feel better if ours did as well.  A vented cap  
is probably not practical, so some other method would have to be  
worked out.

3.  Directional (yaw) stability.  The use of ventral fins has been  
discussed again and it would seem like these devices would be a  
logical addition to at least some models in the lineup.  Stall/spins  
are certainly one of the predominant cause of accidents.

4.  Door safety latches.  No accidents have been caused by IV/ES/ 
Columbia doors opening in flight, but I understand that the doors  
come off, causing damage, especially to the pocketbook.  I haven't  
figured out how to build a "hood latch" type of thing, but somebody  
might be able to.  Also, I have read a report that said the legacy is  
almost uncontrollable if the canopy opens.  I would think that this  
would be of significant concern and in this case I believe a simple  
safety latch could be designed.

5.  I understand that Lancair has recently come out on the subject of  
AOA's.  Right on.

Lancair has been mostly silent on these and other potential  
improvements.  I say "improvements" because I don't want to imply  
that the original design could be called defective and I don't  
believe any accidents (except perhaps one) have been related to  
potential design deficiencies.

Gary Casey