Aircraft Weighed

[cliffy]

On CAR3 airplanes the "empty weight" is calculated with empty oil and only non-usable fuel in the tanks. On FAR 23 airplanes it is calculated with full oil and non-useable fuel. You can pull the sump plugs and drain both or have both full and calculate the empty tanks according to the TCDS sheet capacities. A/C must be level and scales must be calibrated and (if I remember correctly) readable to 1/2 pound for A/C under 6000 lbs.

So on CAR3 airplane you add in your oil quantity when you do your pre-flight W&B (you lose useful load for oil) and on FAR 23 airplanes you've already lost full oil weight (from useful load) before you do your W&B.

[MB65E]

No oil Byron? That's odd... Only airplane I've ever heard of that does that...

For the fuel-I topped mine off, weighed it. Then subtracted the 52 gal of useable.

Not too bad. Beats the de-fueling mess.

If one had access to scales, it's almost easier to re-weigh than to do a calculate reworked items.

Edit- thank for the Part 23 vs CAR3 explanation Cliff.

-Matt

[Lood]

When they weigh a plane, do they drain the fuel, or do they use the fuel gauges to calculate the amount in the tanks?

 

Here in SA, they have to drain the fuel, but the oil is part of the empty weight and is not drained.

[ArtVandelay]

No oil Byron? That's odd... Only airplane I've ever heard of that does that...

For the fuel-I topped mine off, weighed it. Then subtracted the 52 gal of useable.

Not too bad. Beats the de-fueling mess.

If one had access to scales, it's almost easier to re-weigh than to do a calculate reworked items.

Edit- thank for the Part 23 vs CAR3 explanation Cliff.

-Matt

I was told the fuel tanks MUST hold their spec amount, but could be more, so you may be carrying a few extra gallons. Has anyone drain their tanks, then filled them up to check their capacity?

[carusoam]

Yes...

Drained and refilled, early on in ownership, to avoid any surprises with the new-2-me plane...

Long bodies have some variation in the fuel neck venting that makes it a bit different depending on the design...

A patient pilot, on a level surface, MAY be able to get a couple more gallons added beyond the documented full line.

I believe full tanks probably has a definition of "touching the bottom of the neck” documented in the POH.

How does that sound?

-a-

[ArtVandelay]

I check 2 different year M20J POHs and found no mention of that were they define the tank capacity FWIW

I believe full tanks probably has a definition of "touching the bottom of the neck” documented in the POH.
 

[carusoam]

TJ,

From the O's POH...

It is in the service section under refueling....

"The fuel tank is considered full when fuel completely covers bottom of standpipe."

A few more gallons can fit in there, but, like everything else the known procedure has an end...

Best regard,

-a-

[cliffy]

AC 43-13 1B Chap 10-15 Procedures (g) shows how to calculate "Empty Weight" and detail it in the records. (CAR3 vs Pt 23). One must note in the W&B form if the empty weight is calculated with full or empty oil quantity

[Lood]

My F takes an extra 2.3 gal per tank (i.e. 34.3 gals) when filled right up, but when filled according to the POH and triangular reference plate, only 32 gals.

I fill it right to the top just before any long flights, and if needed in an emergency, I will burn 64 gals in total before I land. That way I should land with about 5 gals left.

Under normal cicumstances, I won't burn more than about 55 gals before I land though, regardless of actually still having 14 gals left.

[carusoam]

Follow up...

I looked in a POH for the J...

I was unable to find a reference to the tanks being full when... Like the O's POH.

Best regards,

-a-

[Hank]

I think only long bodies have filler necks, mostly to limit fuel to lesser amounts than the premium models.