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Looking for input and advice from the experts. The M20F I just purchased appears to have an extreme aft CG of 52.83" empty from a weighing done in April this year. One question is the in item #5 which has the nose being -3.5" forward of the datum when the Service and Maintenance Manual (Rev E 9-1-81, pg 2-5) has the nose gear trunion point at STA -5. If I'm correct, that change would only adjust the CG to 50.1"...the aft edge of, but within, the CG envelope. Does anyone else have a similar situation? If so, how do you work with it? How can the CG be reasonably adjusted? I know that any weight aft of the CG is "bad" in this situation and any options to remove aft weight is preferred. For example, the aircraft has an HF clothesline-type antenna from the top of the cabin to the tail which may have options to replace. I was hoping to remove the ADF instruments but not until the CG is addressed. Reasonable suggestions welcome. I've attached the core of the W&B report (tail number, current owner and weigh stations names not include out of respect) W&B.pdf

I've been enjoying my Rocket 305 for three years now. I've made a few upgrades along the way, always dutifully tracking the changes in the Weight and Balance log. I have also corrected a couple major mistakes in the math made long ago. Starting from the original factory Basic Empty Weight of 1923 lbs @ 43.4", 290 pounds of new equipment have been added to the aircraft (mainly the Rocket 305 conversion, built-in O2, and Charlie weights, plus a new COM radio and two G5s). 90 pounds of old equipment originally delivered with the aircraft have been removed (KFC 200, KCS 55A system, BX2000 system, and associated wiring). Q: How much *should* the aircraft weigh now? (Basic Empty Weight, including 10 gallons unusable fuel for the Rocket 305) A: 2123 lbs (@ 43.5") Q: How much does the aircraft actually weigh? A: 2273 lbs (!!!!!!!!) (@ 36.5") (!!!!!!!!!!!!!!!) Obviously, I'm freaking out. That's a 150 lb increase and a 7 inch forward CG shift that are unaccounted for. I've been all through the airplane with my A&P. There's nothing we can find that comes anywhere near explaining even a 15 pound difference, much less a 150 pound difference. The panel looks like a ghost town with all of the ancient avionics gone. I've got 20 lbs of wiring alone that was just removed. There are no errors remaining in the historical W&B entries. I read with great interest Rspencer612's topic Mooney Missile CG. I read about the possibly incorrect arm for the main and nose axles. Even if I can justify ignoring the actual measurements we made, adjusting to the referenced numbers still leaves the CG off by at least 3" from where I expect it to be, and where other Rocket 305s are. I also read that Rspencer612 appears to have resolved his problem by installing the Charlie weights that had never been installed when the Missile conversion was performed. In my case, though, the Charlie weights are definitely installed. I also have a heavy O2 bottle that should be biasing the CG well rearward. We tried this with two different scale sets, and they agreed to within 0.2%. Yes, we followed the correct leveling procedure, twice. We weighed with full tanks and subtracted the weight of 70 gallons usable fuel, per the POH weighing instructions. Has anyone seen a ~150 lb weight increase *and* been able to explain it? I read some comments on this forum and elsewhere about significant weight gains in aircraft as they age, but I haven't found anyone that was actually able to confirm the source of the gain (as opposed to just guessing that it might be dirt and oil, etc.).