Date: Mon, 25 Jun 2001 20:28:29 -0400
From: Marvin Kaye <74740.231@compuserve.com>
Subject: Re: Unusable Fuel
Sender: Marvin Kaye <74740.231@compuserve.com>
To: Lancair Mail List <lancair.list@olsusa.com>
Message-ID: <200106252030_MC3-D727-8E91@compuserve.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
Content-Type: text/plain;
	 charset=us-ascii
Content-Disposition: inline
Reply-To: lancair.list@olsusa.com

          <<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>>
          <<  Lancair Builders' Mail List  >>
          <<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>> 
>>
This is a reply to George Braly's post on Useable Fuel as submitted by Bill
Hogarty <billhogarty@aol.com>:

George:

Read your post on the Lancair list.  Wanted to caution you about your 
suggestion "  to run one tank dry with the other hopefully full"

The problem here is aileron trim....With one tank empty and the other tank
full, you will run out of available trim if you should slow the aircraft
down for any reason.  Some Lancair IV's have the small fixed aileron trim,
and that would really be a problem.   If you are using auto trim, the
situation is even more dangerous because most pilots are not  aware that
the autopilot has cranked in maximum aileron trim.  Then as they slow down,
the wing gets harder and harder to hold up .   Its an accident looking for
a place to happen.

I talked to Don at the factory and he says that Yes, you can restart in the
air after running a wing dry, but it takes time because the electric fuel
boost pump likes to push fuel, not suck.  

Personally, I think that the more prudent method would be drain each tank
on the ground and   then fill each tank to know your usable fuel.. THEN, I
would run each tank dry on the ground and refill to confirm your usable
fuel.  If the readings differ, I would use the worst case to calibrate my
fuel gages.  

Altho I havent flown my IV-P yet, I suppose that eventually I might run
each tank dry to determine the absolute usable fuel BUT only if I had lost
of altitude, was right over an available runway, and for sure I wouldnt
have full fuel in the other wing.  The main reason that I would hesitate is
the possibility of damage to the engine and turbos from the rapid cooling
of an inflight shutdown.  Sommething to think about??????

Best Regards,   Bill Hogarty
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
LML website:   http://www.olsusa.com/mkaye/maillist.html
LML Builders' Bookstore:   http://www.buildersbooks.com/lancair

Please send your photos and drawings to marvkaye@olsusa.com.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>