empty weight

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muehlberg
Posts: 13
Joined: Tue Aug 13, 2013 11:58 pm
First Name: S. Eric
Last Name: Muehlberg
City or Town: Newcastle (OKC)
State or Province: Oklahoma
Location: Oklahoma City, OK

Re: empty weight

Post by muehlberg »

Panther LS S/N 011 has a flying empty weight of 779 lbs unpainted, although all internal metal surfaces are epoxy primed. 011 is equipped with an Piper Colt O-235 C1B (Conical mount saved 5-10 lbs), light starter & alternator, oil cooler, Wood/composite Sensenich prop, metal spinner, odyssey battery (12 lbs), Vans air filter and Vetterman exhaust. Instrumentation includes Dynon D-6 and EMS-10, FL-760 Com, KT-76A, 3 back-up steam gauges (AS, Alt, & VSI) and ifly 740B GPS w/ ADBS in. I fitted, but did not install the wing folding tubes or tripods. No wheel pants yet, but did go with the 6" tailwheel. I install two very small and light wing tip strobes, no nav lights. It is strictly a day VFR aircraft. I have seen in excess of 175 mph indicated at 2800 rpm (Redline) at 3,500' and 60 degrees. I cruise at 150 mph at at around 2400-2450 burning between 5.3 -5.6 gph of 87 oct ethanol free auto fuel. I usually take off with 15-20 gallons of fuel on board (90-120 lbs), I weigh 180-185 + the 779 EW gives me a takeoff weight of 1054-1084 lbs. With 25 gallons I'm at 1114 lbs. CG is about 27% as I fly it.

Could it be lighter? Yes, I could have saved some weight with a lighter battery, smaller tailwheel, and left the oil cooler off. As it turns out, I didn't need the oil cooler with a really good baffling system. There might be 10 or 15 lbs there. I know the above is a lot of numbers, but it is what it's all about. Hope this helps in your decision process.

Eric Muehlberg
N11PX

psalter
Posts: 146
Joined: Sun May 19, 2013 6:50 pm
First Name: Paul
Last Name: Salter
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Location: Green Cove Springs, Florida

Re: empty weight

Post by psalter »

My corvair powered Panther came in at 775 lbs empty with a fairly heavy paint job, wing folds, autopilot, ads-b in and out, grt sport sx

Don't think you can build corvair powered much less than 750 lbs.
Paul Salter
Team Panther
Engineer and Builder

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at7000ft
Posts: 175
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First Name: RICK
Last Name: HOLLAND
City or Town: CASTLE ROCK
State or Province: Colorado
Location: Castle Rock, CO

Re: empty weight

Post by at7000ft »

Interesting, didn't know any Lycoming could go without an oil cooler. Definitely would simplify things. Probably wouldn't work with my 160 hp 320.

Rick H
Rick Holland
N6819Z

LesBoatright
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First Name: Les
Last Name: Boatright
City or Town: Titusville
State or Province: FL

Re: empty weight

Post by LesBoatright »

Not a Corvair engine, but our Panther came in at 796 lbs empty weight.

We have a Lyc. O-235, a simple lightweight fixed-pitch wood core prop, a lightweight SkyTec starter, a simple single color paint scheme, a simple panel with only the GRT Sport EX EFIS, a single comm, the xpndr, and a very light Belite fuel gauge. I also carry an iFLY GPS on a RAM ball mount. Ours is Day VFR only, so no nav or position lighting, and we have no vacuum pump, and no oil cooler either. We observed that our next door hangar neighbor's CITABRIA had the same Lyc. O-235 and no oil cooler, so we copied that, and then made sure we did a really good job on the baffles. We decided we could always add an oil cooler later if the temps ran too warm. However, our oil temps run nicely in the range that's specified in the O-235 engine manual typically between 160-195F, & only very occasionally as high as 210F in Summer with extended higher power settings or at low speed, high angle of attack where cooling airflow is reduced.

We did opt for the heavier 6" tailwheel as I regularly operate on both grass and pavement, but we could probably get away with the lighter stock tailwheel. We could've probably saved some weight by leaving out the wing fold tubes and tri-pod mounts because we never fold the wings, but I love having the option to do so if needed! We also could've saved some weight by going with one of those super light Earthex lithium batteries instead of the Odyssey, but the Odyssey has been rock solid reliable. Even after sitting for as much as a month without flying, the Odyssey battery has held a good charge and started the engine on first try.

Overall, I don't think we could get the empty weight down much more than 20-30 or so pounds, without some more drastic measures. And that would be by deleting the wing fold brackets & tubes, and changing to a more expensive battery.

The Panther is a great little airplane. Best of luck in your decisions!
Les Boatright
S/N 083 "Radio Flyer"

dogger
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empty weight

Post by dogger »

I am curious what builders with a corvair are getting for a empty weight. I'm a heavy pilot at 320lbs. and was looking at cheaper options to build. I will be trying to build light and it won't have much in the way of options but will it be light enough? at this point I'm not planning on the cougar as it looks to be more on par with a rv4 and will require a larger more expensive motor to build. my question is for a heavy pilot is this a option?

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