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Unread 01-01-22, 09:45 AM
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Learjetter Learjetter is offline
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Join Date: Jun 2010
Location: KOKC
Posts: 242
Learjetter is on a distinguished road
Time to eat some crow...

Where do we keep the "crow pie" around here?

Last summer, I reported in another thread on this board that my 77 NA G model had a calculated empty weight of 2957 lbs. Folks expressed some surprise that it was so "light." I was confident in those numbers. I also wrote that we'd be weighing the aircraft this fall.

Over the years, the various mods (avionics upgrades or adds x4, VGs, gear door delete, MT props, new paint and interior x2, etc.) had resulted in a calculated BEW of 2957. I checked all the math over the 44 years of logs and it checked out.

I was certain it was going to check out closer to 2960 (or less!). Just posting to lend credence to the theory that airplanes tend to run a little heavier than their calculated weights.

Weighed it twice, to be sure, with reset on the scales in between. Followed the procedures in the service manual and POH. Readings nearly identical both times.

History:
Left the factory in late 1977 at 2992 lbs CG: 140.15 Useful load: 1638
All calculations leading up to Summer 2021 values of:
2957 lbs at 141.3 CG Useful load: 1672

Imagine my surprise when the scales settled on:
Lt Main 1285
Rt Main 1283
Nose 422

Total: 2990 CG: 139.6 Useful load: 1640

Now, this these are numbers I can have some confidence in.

Aside: jacking a skymaster is a stressful experience.
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