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  #1  
Old 06-22-2014, 05:37 PM
AlinNS AlinNS is offline
 
Join Date: Feb 2014
Location: Welsford, Nova Scotia
Posts: 116
Default Crew Weight and C of G

Hey Folks, just paid my dues and ready to ask some questions.

I'm 6'2 250 lbs the wife is 6'0 and weighs more than 100 lbs less than me (read that twice). I've found a few threads that pretty much say we'll not have too much trouble with space.

More of a concern to me than cuddling in a plane, is the C of G. Can I expect to carry baggage and enough gas for three hour legs on a typical RV7? Three hour legs is based on pee breaks. I have read that aft C of G is a concern for these aircraft?

So I'm just tooling up to build. Pretty much made up my mind it'll be an RV7, but am also finding a Bearhawk Patrol interesting. Kind of like comparing my '67 Mustang Fastback with my '79 F150... very different but both my cup of tea.

One last question for my first post here: Would anybody know of any RV7s in Atlantic Canada that I could get a look at? I'm in Nova Scotia. Don't know of any here.

Thanks All.
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  #2  
Old 06-22-2014, 06:52 PM
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robertahegy robertahegy is offline
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Join Date: Jan 2005
Location: East Troy, WI
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Default

You should be just fine on the W&B in a 7. Fuel and people are pretty close to the CG and have little impact on the balance. You can haul a lot of stuff in the cargo area. Keep heavy things more forward behind the seats.

Roberta
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  #3  
Old 06-22-2014, 07:05 PM
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Location: Cedar Park, TX
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This sounds perfectly reasonable to me. You guys won't have any problem. "If it fits, it ships!" Blast forward without reservation. Really, the W/B works out just fine.
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  #4  
Old 06-22-2014, 08:01 PM
Kyle Boatright Kyle Boatright is offline
 
Join Date: Aug 2005
Location: Atlanta, GA
Posts: 4,361
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It depends. CG is somewhat builder selectable depending on how you choose to equip your airplane.

If you equip it with a light engine/alternator/starter/prop, you'll probably run into aft CG issues as you start loading it up with people and baggage.

If you go way in the other direction (heavy engine, heavy prop, heavy starter, heavy alternator), you'll lose enough useful load to matter.

I'd plan on a metal F/P or metal C/S prop, and go from there.
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  #5  
Old 06-23-2014, 05:30 AM
s24789 s24789 is offline
 
Join Date: Jan 2009
Location: Hobe Sound, Florida
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When my plane partner and I go to oshkosh, we are full of fuel, 50 lbs. of bags, and 420 lbs of us. Just a little forward of the aft cg limit with no issues.
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  #6  
Old 06-23-2014, 05:44 AM
Kyle Boatright Kyle Boatright is offline
 
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Location: Atlanta, GA
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Quote:
Originally Posted by s24789 View Post
When my plane partner and I go to oshkosh, we are full of fuel, 50 lbs. of bags, and 420 lbs of us. Just a little forward of the aft cg limit with no issues.
If you'll paint the whole picture, it'll be much more helpful to the OP.

Are you a "little forward" of the CG limit with full fuel or when you land with 10 gallons left in the tanks?

How is your airplane equipped?
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  #7  
Old 06-24-2014, 05:58 AM
s24789 s24789 is offline
 
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Location: Hobe Sound, Florida
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Take off in those conditions (full fuel, full people, 50 lbs of bags) is 85.7 inches. Landing with 5 gallons in those conditions is 86.5. Aft limit is 86.8. No noticeable change in handling qualities.
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  #8  
Old 06-24-2014, 06:07 AM
Kyle Boatright Kyle Boatright is offline
 
Join Date: Aug 2005
Location: Atlanta, GA
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Quote:
Originally Posted by s24789 View Post
Take off in those conditions (full fuel, full people, 50 lbs of bags) is 85.7 inches. Landing with 5 gallons in those conditions is 86.5. Aft limit is 86.8. No noticeable change in handling qualities.
How is your aircraft equipped? Metal prop? Wood prop? C/S setup?

Those things are important so the OP has the information he needs so his airplane ends up with a CG and useful load that accomplish his objectives.
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  #9  
Old 06-24-2014, 06:13 AM
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Flyguytki Flyguytki is offline
 
Join Date: Jun 2007
Location: Fairbanks AK
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In the 7 that I built, I had a catto prop on it, way to light and would only allow around 40lbs of baggage before I was out of cg if I would have had an additional 40 or 50 pounds of constant speed propeller up there. I would have had no problems at all with full fuel and baggage. Something to think about while you have the time and options.
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  #10  
Old 06-24-2014, 12:07 PM
AlinNS AlinNS is offline
 
Join Date: Feb 2014
Location: Welsford, Nova Scotia
Posts: 116
Default Hey Thanks

Folks,

Thanks for the comments.

Had a nasty experience while inflight refueling on a Sea King Helicopter many many many moons ago that turned out to be an aft C of G problem. Kind of stuck with me I guess.

Anyway. I stumbled upon a number of threads regarding problems with C of G being to far aft on an RV7 and ended up focusing on it. All the responses above have helped a great deal.

I see that this is more of something that can be mitigated while building, so as not have to deal with it as much later.

Started ordering tools this morning. Will order the tail in the Fall.

I'm happy. The wife is happy.

Thanks again.
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