Heavier actual airplane weight

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DrBlackrose

Filing Flight Plan
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DrBlackrose
After I had my Cherokee 140 painted I had a new W&B done. Is it common to find the airplane is actually heavier? There was never an actual W&B done after the original one from the factory just the revisions when something was added or removed. The last W&B before paint was 1297 lbs and after with the new actual W&B was 1395 lbs.
 
Absolutely. You would be surprised how much weight primers and 2 stage paint can add compared to the original lacquer based stuff. People also don’t do new weight and balance for every little thing added over the years. New carpet, a slightly different but same type of instrument, even little things like Adele clamps can add up over time. If you don’t trust your weight and balance you can always stop by one of your local EAA chapters. They usually either have or know someone with a set of scales to borrow. You can’t certify to the new weight with those scales but they will at least tell you if the shop that did yours after paint is close.
 
Very, very common. Dirt & oil accumulate. Mistakes in the w&b get carried forward, and little "negligible" changes add up.

A big one: I pulled 10lbs of unused wire out of my plane. A lot of avionics shops will just clip the wires off old avionics and not bother with pulling them out.

Admittedly, 100 lbs seems like a lot in a Cherokee 140.
 
DrBlackrose said:
Is it common to find the airplane is actually heavier?
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Yes. And sometimes it can be lighter.
DrBlackrose said:
just the revisions when something was added or removed. The last W&B before paint was 1297 lbs
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If the 1297 was the previous EWB based on those prior "revisions" it doesn't always mean there was an actual 98 lb difference. When calculating new EWB mathematically, the "moment" produced is not directly related to the actual weight. So over time of only calculating EWB you can add, or subtract, "weight" simply as a result of the math. If that makes sense. This is also the reason certain aircraft are required to have an actual EWB performed every 3 years to correct for the "moment" drift and other anomalies as noted above.
 
Did the original W&B include things like a fire extinguisher, first aid kit, an ELT, and other stuff like that? Did it include the oil in the engine? It would have included unusable fuel, so did the shop drain the tanks and then add unusable fuel to get the empty weight right? What junk might have been left in the airplane?

Old airplanes gain weight. Just like old people. Don't ask me how I know.
 
Dan Thomas said:
Did the original W&B include things like a fire extinguisher, first aid kit, an ELT, and other stuff like that? Did it include the oil in the engine? It would have included unusable fuel, so did the shop drain the tanks and then add unusable fuel to get the empty weight right? What junk might have been left in the airplane?

Old airplanes gain weight. Just like old people. Don't ask me how I know.
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I'm not sure their procedure for the W&B. Lets hope they removed "junk". I will ask the next time I'm by the shop. I just thought 100 lbs was way off. The thing is I have to find out if this is totally correct because no matter how I try I can not get into the utility envelope any longer. It's not like I use utility but it's no longer available with this new W&B.
 
It’s been a while (20 years), but my 140 gained around 60 lbs when it was weighed. Disappointing but a previous owner had the plane painted by a lousy outfit and I had made several modifications (adds and removals). We thought we did all the math and measurements correctly but…
 
You assume the original WB was correct. It may not have been.
 
Chances are they didn’t bother to do it correctly. Did they empty the fuel tanks, remove the extra junk you are carrying, etc?
 
I added the back shelf option and knots2U wheel pants to my 68 140 and it weighed in about the same as yours. So not out of the ordinary for older birds to gain weight. It still leaves you with 755 lbs useful load.
 
When I painted my Cherokee, I stripped it, Primed it, and painted it, removed old Narco Mk12, ADF, and MX12. Installed kX125, MK12D, audio panel, and removed a bunch of old wire. and gained 60 pounds of weight.
 
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