simurqq wrote:
Just to clarify: I guess the "Oil" cell requires input in pounds, not quarts. So, judging from
this specification, 8 quarts of oil = 2 US gal = 14.88 pounds. Can you confirm?
This is getting into A&P territory... personally, I think that it is excellent you guys are taking the time to think about these things - so I submit the following:
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"For aircraft certified since 1978, full engine oil is typically included in an aircraft’s empty weight. This can be confirmed by looking at the Type Certificate Data Sheet. If full oil is to be included, the oil level needs to be checked and the oil system serviced if it is less than full."
"The standard weight for lubricating oil is 7.5 lb/gal (1.875 pounds per quart)"
Aviation Maintenance Technician Handbook - General
Chapter 4: Aircraft Weight and Balance
[From TCDS No.3A12]
Data Pertinent to Model 172R: (cont’d)
NOTE 1: Weight and Balance:
Serial Nos. 17280001 and On
The certificated empty weight and corresponding center of gravity location must include unusable fuel of 18 pounds at 46.0 inches aft of datum, and full oil of 15.0 pounds at 13.1 inches forward of datum.
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Oil (in this case) is included in the Basic Empty Weight and one would use the figure of 15lbs for full oil... but this is ONLY if you are attempting to determine the Basic Empty Weight... something you would only do as an A&P as there is going to be a logbook entry & sign-off needed by an appropriately certificated mechanic.
How does this impact your Weight & Balance calculations? In this case it doesn't -- you don't concern yourself with how much oil is in the engine for Weight & Balance Purposes.
That link Scott provided is spot on where it says, "Oil (8 Qts)included in basic empty above as per POH". And you can see there, one does not have the ability to change the "Zero" figure to anything else as it is grayed out. Hope all this helps...
-Rob