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jrthomas
08-21-2009, 10:36 AM
I have a mod IV with a 912ul, speedster, taildragger with Grove gear. I expect to weigh 650 to 675 pounds when finished. At 1200 lbs max take off weight this will leave me 525 to 550lbs. With 2, 200lb adults and 27 gallons of gas I'd be overweight. Of course I'b be the only one to know but here's my questions. (1) As long as CG is inside limits, what does it matter? (2) Can a mod IV 1200 be registered with a max take off weight at more than 1200lbs? When I had my CGS Hawk registered and inspected, I set my max gross myself and no one questioned it. Thanks, James Thomas

Slyfox
08-21-2009, 11:09 AM
with 2200lb of adults you are way over. I can't even see you being able to get in the plane. sorry couldn't resist. :D

SkyPirate
08-21-2009, 11:18 AM
Hi James,..it would matter most on a high altitude field with hot temps.
could just put 20 gallons of fuel on board with 2- 200 lb passengers ,.I had a chart that I made for my model 2,..me plus 100 lb passenger equals so much fuel ..150 lb passenger equals so much,.. 200 lbs ..drain the tanks and hope the vapors expand enough for a 10 minute flight :)

one could
start at 20 gal. or within your 1200 lb gross ..take note of air temp,.. density,..etc.. take off roll distance,
try 22 gallons ....24 gal..when you start to feel uncomfortable with it's performance,..minus 2 from that point taking in consideration all the factors,, temp ,,density ,,etc?
there is nothing saying you can't put a 100 lb weight in the right side seat ..or even 200 lbs during the first 40hrs ?

Chase

if you plan to do this get a couple boxes of 1 gallon zip lock baggies ..put sand in them and tape them up,..and put them inside of a duffle back ..run the seat bealt on the passenger side thru the handles /straps on the duffle bag ..no chance of it moving around in flight .

Slyfox
08-21-2009, 12:24 PM
since you are the builder, you can put whatever on the gross weight. Go an extra 50lbs on the gross that will keep you out of dodo with the faa. I did this with my RV, put a little extra on the gross weight for the in case of. Doesn't mean you have to go over the limit. But if it happens than you can be safe with the faa. I would do like chase said and make up a weight and balance for the amount of fuel to make things just right.

jrthomas
08-21-2009, 01:58 PM
Thanks for your answers. The forum has been a little slow so I thought it might be a good time to ask and get some discussion going. I like the idea of listing max gross at 50 pounds over but I was unsure if it was legal. The Kitfox sure looks to be sturdy enough. Good idea too to add weight to the passenger seat rather than my wife,(No , she doesn't weigh 200 pounds)during my testing phase. Crash test dummys are hard to come by. Thanks again for the good advise, James Thomas

SkyPirate
08-21-2009, 04:08 PM
well ,..I've been a bullet stopper dumby ,..an explosion dumby, my face stopped the floor from falling up once,..ok maybe twice:o..never been a crash test dumby ha ha sounds like a step up for me :D

Chase

jrthomas
08-22-2009, 04:49 AM
Hey ya'll, I think I'll go with the 1320lb max gross. I doubt I'll ever come close to loading this heavy but that weight will leave plenty of breathing room and still have the advantage of meeting light sport specs. I'm trying to build light but it will be nice to know that my plane is capable of carrying an extra heavy load for some cross country or camping trips. Thanks again, James Thomas

Slyfox
08-22-2009, 12:03 PM
just don't go over the sport pilot, I think 1335lbs for gross, that will kick out future sale or if you need it.

jdmcbean
08-25-2009, 02:01 PM
OK guys... This is wrong.

The Kitfox has been load tested.

While you are the builder and you can establish the weight at whatever level you choose you may have to and should document and test the limits you have established. Will the aircraft handle more weight ?

We rate and have tested the aircraft at the established gross weights, 1200 lbs for the IV and 1550 lbs for the 5 and newer models, to 3.8+ and 1.5- G loads sustained. It was tested to approximately 6+ and 3- ultimate loads. Using the guidelines establish safety margins in standard catagory aircraft and calculations for gust loads is how the sustained loading was figured.

To arbitrarily say it will carry more is unsafe. In smooth air under normal conditions you may be ok.. but the safety margins are not there when that unknown gust or speed bump occurs.

Again, the Kitfox has been load tested to the limits established. We highly recommend you stay within them.

Slyfox
08-25-2009, 02:14 PM
Thanks John, I totally agree with you.
With that, I will not at any time go over the 1200 in my kitfox, never have, never will. The best thing to do is lay off the twinkies and fly light. The kitfox, any model, is best when flown light.

jrthomas
08-25-2009, 06:12 PM
Thanks John, Your advise is appreciated and it will be taken. James Thomas