"Andy" wrote in message
oups.com...
On Apr 13, 7:04 pm, Eric Greenwell wrote:
What I think Kilo Charlie and the others are trying to determine is
if
it's even worth taking a towplane to this potential site. Without
experience at a similar site, looking for pertinent numbers seems like
a
better idea than just showing up and trying it.



No, ASA has flown at the site (Clark Memorial, Williams, AZ ) before
but for our next contest there the organizers have decided that water
ballast will not be allowed. Some members have questioned that rule
on the basis that some pilots used water ballast last time they were
there and thought the risk was acceptable.

I think limiting the discussion to takeoff distance misses the point.
I like to know if I can expect a climb rate that will allow me to
return to the airport, or other known safe landing area, from any
point in the tow.


Andy

Eric has hit it on the head. Andy is a very knowlegable pilot but at least
last year did not fly out of Williams in his glider (he came to visit in his
airplane with a broken arm) just as a matter of full disclosure which seems
to be where he was attempting to head.

I honestly don't care which parameter you choose.....takeoff distance, climb
rate, etc. I would think that it all will have a decent correlation wrt
density altitude.....but then I'm just a stupid doctor and not an engineer
like Andy.

We have NO airports with safe bailout fields anymore....not that we ever did
but Turf had a potential spot at least. So its a totally moot point re
that. I have towed at gross weight out of Ely (6200'), Parowan (5900') and
Moriarty (6200') and yes the takeoff rolls were long and the climb rates
were low but by the end of the runway or just beyond was at 200 feet and the
experienced tow pilots did a slow low bank turn back over the airport until
we were at a high enough altitude to look for lift elsewhere. I never felt
that my life was in more danger there than on a 110 degree day at 2000'
towing uphill with no wind at El Tiro which we do all of the time. The ASA
is also now towing out of a 3900' length runway uphill on the lee side of
some hills. So where do we draw the line?

So I do think that Eric is correct in that I do wish to have the best
numbers we can generate wrt takeoff distances (or climb rate!) so that we
have a starting point to evaluate a go, no-go situation whether it be
heading to a high site on a very hot AZ weekend or whether or how much water
we may put in.

The data would be helpful....period. If the naysayers wish to ignore that
its their choice. I for one believe my POH and along with some common sense
will be following it for my Columbia on hot days and would like to be able
to use it for my LS-8/Pawnee combo too.

Casey