Re: 2 recent incidents

On Wed, 25 Jun 2008 16:17:18 -0700, Ramy wrote:

There is more to be learnt from the other incident:

> 2 - Another restricted control due to unsecured item. I bet this caused
> more accidents then we know of.
> http://www.ntsb.gov/NTSB/brief.asp?ev_id=20080606X00809&key=1

<quote>
The glider pilot stated that he "could not push the stick all the way 
forward to lower the nose" and the glider continued to climb out of tow 
position ... The pilot selected full nose down trim, in response to his 
limited pitch control.
</quote>

On gliders with a tab trimmer on the elevator, like the K13 in this 
incident, full NOSE UP trim will actually give you more "elevator down" 
authority, nose down trim will make things worse. 

The trim tab moves down when you trim nose up. With the elevator as far 
down as the obstruction would let it go, nose up trim up would make the 
trim tab go down a little further.

A more common use of this phenomenon is when you are doing spin training 
with a heavy pilot in the front seat. If you trim full forward you a 
little more elevator up authority which makes it a little easier to get 
the glider to enter a spin.

Ian