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smcnutt
04-20-2011, 11:41 AM
We have the chance to borrow some scales and we wanted to double check our W&B on our PA-22/20. I know it won't be legal unless it's done officially but like I said, we just want to double check what our form says. If we find it's off from what our form says then we will have it done officially.

How exactly do you weigh the airplane? Does it have to be in level flight (tail up) or landing config?

I've downloaded the spreadsheet/form from the CubCrafter website that another thread pointed to. I think with that I will just need to input the numbers.

ysifly2
04-20-2011, 12:39 PM
I believe it should be leveled per dwg 13942.... tail up. There should be a small hole in the top ledge passenger door that you hang a plumb bob down to point and align to a dimple in the front seat cross tube.

I attached a spreadsheet that I used to input / play with my numbers for what it is worth.
The W&B tab is where I input the measured weights, log the installed equipment and any adjustments.
The N4763A W&B tab is the pre-flight worksheet (with some linkage to the W&B tab) that I play with to ensure in balance, playing with usable fuel which then projects a "range" and duration.... also gives beginning and ending flight CG.
Not yet 100%, but built and based upon various excel formats that I have seen.
2509


Bryan

MN_flyer1
04-20-2011, 05:11 PM
Depends on if you want to double check the weight or the balance as well. The balance requires it to be leveled per Operators Manual. If your weight is where the book says it should be I bet the balance is as well.

P.o.P.
04-20-2011, 09:43 PM
Aircraft must be Level.

Empty Fuel & Oil OR FULL on each & calculate Fuel & OIl Weight & MOMENT removal later.

tnowak
04-21-2011, 02:24 AM
May be different in USA, but W&B here is with empty fuel tank(s), but with the required amount of oil in engine.

Also, your existing W&B paperwork should state what was in the aircraft when the W&B was last done (equipment list). That way you can account for any extras like radios, fire extinguishers, plush carpet etc. etc!

It isn't that difficult to work out the C of G position manually as long as you know where your datum is and have all your measurements to hand (distance from main wheels to tail wheel etc.).
Tony Nowak

P.o.P.
04-21-2011, 10:00 AM
As Tony stated ; the Equipment List is VERY important.

It should agree with your W & B.

I've seen aircraft where Fairings were REMOVED 3 times ( no Install!) or vice versa.

Also measurements are in Level Flight Position.

A floor you can write on is handy.

Nathan Hiebert
04-21-2011, 11:39 AM
I'm with Tony...Anytime I've ever done a W&B on a Cessna (sorry to throw that word out there) single engine, I've always defueled the aircraft to UNUSABLE fuel (don't sump the tanks), and the engine oil serviced to full capacity. Then balance the aircraft in a flight level condition. Maybe it's different on Pipers?????

Nate

rocket
04-21-2011, 01:57 PM
I would break out your trusty AC43.13-1B. There are a number of nice illustrations and examples in chapter 10.

I find I can take some air out of my nose wheel to level but I have 8.5 on the mains and 8.0 with the Landis fork on the front.

I assume you know about the punch mark.

My flight manual has a nice drawing and it looks like Piper just copied the AC 43.13 drawings...or the other way around.

Rocket

P.o.P.
04-21-2011, 01:59 PM
The "Empty" on Fuel I referred to is removing all Useable Fuel. Do NOT drain sumps.

Placard on quantity should refer to Useable Fuel so it's easy to compute.

About 1978 the option to have a "Basic Empty Weight" that includes oil originated.

Cessna used that on most of the aircraft after that.

I think you will find a C-150 "Empty Weight" does not include oil while the C-152 "Basic Empty Weight" does include the oil.