Pa-17 Weight and Balance Questions

[Shepherd]

As most of you are aware, there is no "real" Pilot Operating Handbook for the PA-17.
My documentation is quantity 4, 8 x11 inch mimeographed pages, one of which is for Weight and Balance.
Not a problem. I learned how to do this back in 1965.
But I do have questions:
Why is the example for calculating "Most Rearward C.G." for the Utility Category calculated with - Empty Weight (673 lbs), 1 gallon of oil, 5.42 gallons of fuel and Pilot Passenger and Parachute and nothing in the baggage area?
5,42 gallons? how do you even measure that?
With 12 gallons, and just me in the plane I'm well within 12.5 inch forward and 17 inch rearward limits for Utility. It's actually at 13.9 inches. I'm 177 lbs underweight, and that includes my chocks and flight bag (18 lbs) in the baggage area.
Is this telling me I have to have ONLY 5.42 gallons of fuel on board?
Do I have to have a passenger and parachutes?
Is it saying I can't have anything in the baggage area to be Utility?

Sorry to bother everybody (anybody?). I'm grounded. The weather terrible, I have a horrible head cold and I'm miserable, so I figured I share the suck.

Wait until I start asking about take-off and landing performance. There is absolutely NOTHING in my 4 page of "documentation" about this.

 

[dgapilot]

1. The TCDS prohibits baggage while in Utility Category.
2. the 5.42 gallons is a certification requirement under CAR 3.11 where it is calculated for the most adverse condition for stability as 1 gallon for each 12 HP. 65/12=5.416. More gas drives to a more forward CG so better for stability.

Performance is based on 3.122 for take off and 3.124 for landing. Only one number as only one condition is explored.

 

[Shepherd]

So my C-85-8 would be 85/12 or 7.083333333. Good to know.
I'll strap my bag on the seat next to me.

I don't understand: Performance is based on 3.122 for take off and 3.124 for landing. Only one number as only one condition is explored.
I can't find any similar reference on my pages.

Thanks for the info. It helps a lot.

 

[dgapilot]

So if you have an 85 installed, does the STC still allow Utility operations? lots of STCs only test to Normal and end up dropping the Utility. It requires a lot more flight testing.

Go download the 1946 version of CAR 3 and read it to understand the certification requirements. FAA DRS doesnt have that version, you have to go to the DOT site to find it.

 

[tnowak]

Is your empty weight really only 673 lb? If so, I assume no radio installed, no transponder, small Scott tailwheel and original seats etc.?
My empty weight is 735 lb..
I can account for some of my Vag's extra weight but really do wonder how Piper got PA17s off their assembly line weighing so little...
TonyN

 

[Shepherd]

Is your empty weight really only 673 lb? If so, I assume no radio installed, no transponder, small Scott tailwheel and original seats etc.?
My empty weight is 735 lb..
I can account for some of my Vag's extra weight but really do wonder how Piper got PA17s off their assembly line weighing so little...
TonyN

No electrical system at all. Original instrument panel, original seats, single seat belt, no sound proofing, Maule tailwheel.
When they recovered the plane in 1998, they made a note that the plane was 11 pounds lighter with the new covering. But it buzzes, rattles and hums.
At full power during takeoff, the plane is so loud you can't hear anything on the radio, even with the volume all the way up.

 

[Shepherd]

So if you have an 85 installed, does the STC still allow Utility operations? lots of STCs only test to Normal and end up dropping the Utility. It requires a lot more flight testing.

Go download the 1946 version of CAR 3 and read it to understand the certification requirements. FAA DRS doesnt have that version, you have to go to the DOT site to find it.

So far, I'm unable to locate the 1946 CAR 3. Still looking........

 

[dgapilot]

Plane and Train Crashes! (planeandtrainwrecks.com)

 

[Shepherd]

Plane and train wrecks.
The next place I was going to look for aircraft weight and balance documents.
Thanks for the link!

 

[dgapilot]

Go figure for the DOT to name their web site Plane and Train Crashes!


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[Rene]

Go figure for the DOT to name their web site Plane and Train Crashes!


Sent from my iPad using Tapatalk

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