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W&B question

uk_figs

uk_figs

Well Known Member
Friend
I have two bags in my -7 for tie downs and tools etc that are strapped in between the flap control rod and the back of the pilot/pax seats. From a W&B standpoint would you treat these as pilot/pax weight or baggage weight.

It makes quite a CG difference with 2 up, baggage and min fuel.

I created a spreadsheet with these as a separate station and arm/moment (114.78) but wondered if I am being too anal :)
 
I'm an engineer - I'd do what you did and create a measured station for them. Why estimate and be less accurate?
 
What Paul said is best although if I were going to choose between pilot / passenger vs baggage, I think it's more conservative to treat as baggage since the RV7s I've seen move the CG aft over the course of a flight as the fuel burns.

Dan
 
You know what the datum is I believe it is 70 inches to the leading edge of the wing... I would have to look this up.. just measure from that point to where your placing the bags and get an accurate arm. then add it to your calculations as a seperate line entry.. you might not always carry the bags so to eliminate the weight is handy too.
Jack
 
Figs,
I agree on all.
Also check the baggage area.
It can be split in two.
Heavy close to seats and light weight in the back
Very general station # IIRC
Also check pilot and co pilot stations.

Hope this helps.

See ya in Oshkosh:eek::eek::cool:
 
All valid inputs

Thanks for the inputs, the question was somewhat driven by me buying a W&B app for my iPhone to find it only had Pilot/Pax, baggage and fuel stations with no apparent ability to add additional stations.

Think I will stick with my spreadsheet but measure and add the specific baggage stations as suggested above
 
I use Aviation W&B on my iPhone and though you cannot add more locations, you can combine and rename existing ones. For example, combine front right and front left into Front Seats and same for Back Seats. You can then use the remaining 2 fields for other locations.
 
As another engineer, I'm with Paul on this one. The only thing that matters in determining the cg is the weight and station of each item; it does not matter in the least what you call them. Your use of a spreadsheet is exactly what I do with the Tiger that I fly while creeping through my 7A build. You can make one in minutes, and use it in seconds, for any airplane if you have the data. Some things you just don't want to approximate, your life may depend on it.
 
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