Piper Empty Weights?

My '41 J4A came out at 951 lbs empty weight. According to the 337s the typical weight before restoration was 819 lbs. The original included full electric with battery, old heavy weight starter, air powered generator, & had an A-75 Continental engine. This was all removed.

I substituted a C85 engine, a metal prop, a lite weight starter & a power socket. Otherwise no electrics, but ended up at 950 lbs!

Did someone at Piper originally have their fingers on scales pulling up? My IA says it is not at all uncommon. Has anyone else had this sort of experience?:(

What recovering system was used on the airplane originally vs the most recent rebuild. Modern materials are more durable but usually weigh more in practice. More folks apply more finish than the instructions suggest.

Metal propellers weigh significantly more than the original wooden ones. The C-85 is heavier.

It all adds up....

Best of luck,

Wes
N78PS

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Originally Posted by nrpetersen

My '41 J4A came out at 951 lbs empty weight. My IA says it is not at all uncommon. Has anyone else had this sort of experience?:(

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Minor weight gains are not uncommon but ~15% should have an explanation considering your mods. Did Someone repair the fuselage with water pipe? Don't laugh, has happened before. Douglas fir wood? If you think the hardware is in order, start with the '41 w & b and see if there were any errors in the calculated w & b over they years. That happens too.

My Vagabond shows 618 lbs delivered.When I got it it was 800 lbs and I now have it pared down to725 lbs. Two wing tanks and no fuselage tank and a C85.Personally I think they filled them with Helium beforeWeighing at the factory.Dave

There's a a lot of discussion regarding "optimistic" empty weights on the Shortwing forums. The TriPacer is listed at about 1,110# empty and rarely do you see one at that weight. As others were saying, the covering system can add weight quickly, especially if it is urethane based.

FWIW - My J4A is covered with Randolph butyrate dope. Brush coat of DacProofer, one spray coat of rejuvinator, two coats of clear, 2 of silver, 2 of white, and three of color. That seems to be the minimum recommended by the manual. The fabric weave is still very evident. That may be the primary source of the overweight though. Also the metal prop & the larger engine. It seems as though there isn't much credit for the electrical system though, and there hasn't been much metal rework either.

Interestingly enough, there doesn't seem to be any posted weight change thru about 8 337s.

My Piper J5A with a Lycoming O-290D and electrical system came in at 985 empty. But I installed PA-12 wings and fuel system which added about 50 lb over the single right wing tank and wood spar wings, and the Lycoming engine which added about 100 lb. over the original Continental A-75. I saved some weight by using an AM series Sensenich metal prop (saved 10 lb. over the DM series) and I used a Skytec lightweight starter (saved about 12 lb.). I also used a Odyssey sealed battery which saved 12 lb over the Gil. If I could ever get an STC or field approval I could probably save more weight by using an alternator instead of the Delco Remy Generator. And if I ever get around to it, I plan to convert to a Sensenich FM series wood prop which will save an additional 10 lb. over the metal prop. It adds up quickly. But taking it away takes years and lots of work and money.
-Joel