View Single Post
  #16  
Old April 1st 05, 01:47 AM
Dave
external usenet poster
 
Posts: n/a
Default

WHOOPS!

Thinking one thing, typing another.......

On Thu, 31 Mar 2005 08:16:05 -0400, Dave
wrote:

maybe causing this center to be well aft, like a
float plane without the sometimes required sub fins added...


Should have written.."causing this center to be well _forward_"....

...Sorry.....

Dave




Interesting..

I have not flown one, so I have to depend on the thoughts/theories of
others.

The Aircraft appears to be correctly ptoportioned with the
possible exception of the center of laterial (side) area, (smallish
vertical fin/rudder) maybe causing this center to be well aft, like a
float plane without the sometimes required sub fins added...

But no one has reported any yaw instability or dutch roll
tendencies. (?)

Spin recovery/training is part of the training in Canada, - we
spin ours often just cause it is a hoot and keeps us aware of the
"feel" of what can cause a spin etc.

We get to practice our recovery techniques often, and feel
it's a good thing to do in trying to stay "sharp" with the aircraft..

Nice aircraft, but the whole idea if an aircraft that has (for
me) a serious design issue is troubling.

Thanks for your reply..

Dave


On Wed, 30 Mar 2005 17:15:22 GMT, "Dude" wrote:


Anybody here have any theories as to why (aerodynamically) this design
has recovery problems?

Dave


I got theories, but given my level of expertise, they are better labeled
guesses. I have to warn you that just asking that question is considered
heresy by many. Obviously, anyone outside of the government or Cirrus would
have to have a LOT of resources and motivation to figure this out for real.
Maybe one of the big insurers might care enough, but they would likely only
bullly Cirrus into doing the testing. USAIG has reportedly come to call in
Duluth, but has not yet demanded that Cirrus perform the normal tests in
spite of the BRS supported waiver.

Looking at a Cirrus it seems to me the CG may be too high above the wing.
Of course, this is even more true about many modern Bizjets, but intuitively
it would seem to be a bad thing for spin recovery.

The wing loading seems to be pretty high compared to the weight of the
plane, but I have no idea how this relates. In fact, if you look at the
Bizjets again, it would seem that this is not necessarily a problem.

Lastly, the shape of the wing is very complex, and it would seem that they
over did it on the spin resistance bit. How this makes it tough to recover,
or even if its a factor is unknown.

The bottom line may be that the growth of BRS technology that Cirrus is
indirectly funding could be worth the losses in the long run (not that the
families of the lost will see it that way). It could also be that after we
get another few million hours, the Cirrus will prove to be as safe as the
Cessna's and Diamonds (but I think the verdict is in already).

For me, it all didn't matter. I am convinced that the quality is just not
there. In spite of the G2 improvements, I think they are still a long way
behind the other major players, and especially behind Lancair and Diamond.