which wing / what engine to select ?

[Exhaust guy]

There a number things that can be done to make the 0-320 quite a bit lighter as I stated in a previous post. On my E2D I removed the original sump and installed the ECI magnesium sump. I made a set of aluminum intake tubes to replace the originals. The light weight starter and ring gear saves some weight as well as the B&C small alternator. I also fabricated a set of fiberglass plenums to replace the original style baffling. Yes, keep it light as possible as one well known aircraft kit manufacturer stated, be very aware of every gram and the pounds will take care of themselves. Good luck. Larry v.

[Tony Spicer]

My RV-3B with O-320 and Catto prop weighed 792 lbs.

My painted Panther/Jab weighs 723 lbs with 33 lbs of lead bolted to the front of the engine.

The Panther prototype weighs 754 lbs.

My guess is Ben Krotje's Panther/Jab with the extended mount/cowl will come in under 700 lbs with paint.

Another guess is the average weight of both Panther models with an O-320 is in the 840-850 lb range. 150 lbs in an airframe the size of the Panther is a huge amount!

For best all-around performance, keep it light!

Tony

[psalter]

I don't have all the information on weight at my fingertips at the moment.

I am not 100% familiar with all the weights of an RV-3, Dan has stated that the Panther does have about a 10-15% weight penalty for the basic airframe, no engine or avionics. Part of that is because of the options available, size of the cockpit, adjustability, steel cage, etc. Nothing is ever completely free in engineering.

No matter what engine (100hp+) you install, you will have a fun to fly aircraft around the pattern with 2+ hours of fuel available.

An engine with around 1.5 times the horsepower, will give in general about 15-20 mph top end speed, about 1g higher sustained maneuvering Gs , and of course a higher rate of climb, the Corvair 3.0L demonstrated approximately 1700 fpm in Florida summers.

Cruise speed is highly dependent on how much you pull the throttle back, and if you want to fly in the LSA category. A smaller engine Panther and a larger engine Panther or RV can still fly formation together, if a reasonable speed is determined for the group. This has been demonstrated in many flights around our field with many RVs and several Panthers.

Bob or Dan are better suited to give a comparison between the long and short wing as they have flown both. In general, landing characteristics are similar between both, except the longer wing has a bit better glide, and might float slightly more especially if carrying more speed than necessary. Again, I leave the specifics to ones who have flown both.

[FoesFlyDennis]

Please let me chime in to thank Paul Salter for his thoughtful reply. All these points seem obvious now that someone with your qualifications has listed them. These considerations will all be relevant to me once the Cougar becomes reality.

[Larry DeCamp]

Thanks to all for the input. Assuming the same engine accessories and avionics, my focus is on the implications of the extra 65 lb up front with a Lyc engine. My mission is 95% 30 minute to 2hr flights for fun. Not much 8K traveling. That said, it is my impression the basic Panther is a little heavier an RV-3B (before adding engine/mount weight). True or false ? The distinction I am curious about is :
1- How does corvair (100 HP ) LS compare to an 0320 conical for flying properties ?
2- What is the implication ( plus and minus ) on flying characteristics with the sport wing ? I don't want a Pitts Special landing personality !!!
Thanks in advance....Larry

[psalter]

First thing you need to do on deciding a wing version (long wing Light Sport or short wing Sport) is define your mission.

If you want light sport capable, long wing.

If you want smaller engines, long wing.

If you want better high altitude performance, long wing.

If you want better roll rates and have a larger engine and don't care about light sport, short wing is a possibility.

I don't know the exact percentages, but the majority of orders are long wing.

There is very little difference in weight between the long and short wing, and that difference is easily overtaken by what you put in for avionics, engines, batteries, even paint.

Of the ones flying at Haller, one of the long wing versions is slightly lighter than the short wing version. The 2 aircraft are virtually identical except the long wing has a conical mount O-320, the short wing one has the heavier dynafocal mount O-320.

[Tony Spicer]

I am trying to decide what Panther to build. I am flying my 0320 RV-3B and will purchase A Panther kit as soon as the decision is made.

Larry,

Unless something has changed, all the kits are basically the same. Want a Sport, just cut a foot off the wingtips and flaps. Rachel is standing by to take your order

Did you get the PM I sent you last week?

Tony

[Lowrider]

Larry...thanks for bringing this up for discussion. I've had the same thoughts. I'm building an overpowered LSA high wing due to the high fields and density altitude issues here in the West and my thoughts in that regard spill over into the Panther which I'd like to make a follow-on plane. A loafing 0 320 gives the advantage at 8K on a 90 degree day over a screaming 0-200.

I look forward to the thoughts of others.

[Larry DeCamp]

I am trying to decide what Panther to build. I am flying my 0320 RV-3B and will purchase A Panther kit as soon as the decision is made. I have read Wooleys excellent feedback and the Minnisota report on the LS version. I have observed that weight is significant on these light ships. My RV is a different airplane with 1/2 tanks vs Full tanks because that fuel is 10% of gross weight. So, I Am struggling with the tradeoff between a 100HP sport wing and 150HP sport or LS wing.

My suspicion is an 0200 pushed to 2700 Rpm cruise will burn the same fuel as an 0320 loafing at 2200 going 150IAS? So, I am guessing the lightest most fun config is 100HP with sport wing. I would appreciate your thoughts....Larry