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ACRO E-mail Archive Thread: [Acro] Re: New Pitts owner needs S-1S wt & bal ...


Thread: [Acro] Re: New Pitts owner needs S-1S wt & bal ...

Message: [Acro] Re: New Pitts owner needs S-1S wt & bal info.

Follow-Up To: ACRO Email list (for List Members only)

From: "David Pilkington" <David.Pilkington at>

Date: Sun, 18 Aug 2002 08:52:55 UTC


  As you're going to weigh an airplane you know little about:
when its levelled - take a plumbob and drop a line to the ground at each of
the points you need moment arms for. Mark a chalk line on the hangar floor
then measure all the distances. You'll probably find that they are different
from the book figures.

For more info, see

----- Original Message -----
From: "rklarich" <rklarich at>
To: <Klusmanp at>; <acro at>
Sent: Sunday, August 18, 2002 10:27 AM
Subject: [Acro] Re: New Pitts owner needs S-1S wt & bal info.

> Paul,
> Congrats!
> Yes, Level is the upper/top fuse. longerons.  This data is from the
> S1S aircraft owner's manual- with your height I'm sure you have at least
> S1S stock fuselage length, but if it is longer, you'll have to know where
> it's longer and I'd say find the original w&b.  Lateral level is accross
> these top longerons in the cockpit.  Tailwheel will weigh around 60-75
> pounds once up level, but more than that on the ground- careful on the
> and whatever on the tail you lift by.  FS 50.44 is the main gear position,
> FS 171.0 is the centerline of the fwd attach bolt on the springs for the
> tailwheel- it's your fulcrum, see pg. 3 of 15 of the manual- aviat or
> someone can fax you one- email if you need a fax copy, use at your own
> of course...  120.56 inches between the center of the fwd gear axles up
> front and the fulcrum of that bolt that the tailwheel springs mount to.
> Datum is 65.06 inches fwd of the leading edge of the lower wing.
> First run thru is at Zero fuel weight.  Engine oil is at 33.26, radios at
> 65.88 stock, full fuel is at 59.63 /120# for your full up considerations
> starting acro with a full tank, maybe interpolate too for contests at 10
> gals/half tanks.  Stick gets light with lots of baggage in the turtledeck
> while in the flare going cross country with just legal reserves at
> for some of us....
> Say hi to the Colonel for me.
> Rich Klarich
> Purdue Det 220 1989-1993
> Altus, OK
> IAC 21376
> ----- Original Message -----
> From: <Klusmanp at>
> To: <acro at>
> Sent: Saturday, August 17, 2002 3:15 PM
> Subject: [Acro] New Pitts owner needs S-1S wt & bal info.
> > I finally bought a Pitts S-1S!
> >
> > I'm going to weigh the airplane to update the weight and balance and I
> need
> > to some info from you S-1S folks out there:
> >
> > -What is level reference on the airplane? (I'm guessing you raise the
> to
> > level the top fuselage longeron?)
> >
> > -Where is the datum reference? (firewall?)
> >
> > -Where are main and taiwheel locations relative to datum?
> >
> > Thanks,
> > Paul Klusman
> > Pitts S-1S (finally)
> >
> >


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