Jake Ruddy

My Feedback: (40)

Well the wingloading will be 28.56 which is decent for a plane this size.


As far as the EF 78" Extra that is coming out.. it will have similar wing area to this plane but be somewhere around 12-13 pounds if I remember correctly. If you look at the 74" Yak it is smaller and has 1120 sqs. The 78" Extra will be able to be a similar weight but have a slightly larger wing.

Personally I am hoping it has a pipe tunnel.. have a Brillelli 26 that should fly the heck out of it on a pipe and keep it super light

bodywerks

My Feedback: (4)

At 1200 sq.in, it might just be an OK performer! 1029 would bee too heavy on the wing for really hardcore flying, but still OK for sport-flying.
After looking at similar offerings from Aeroworks, for the 79.5" span, it seems like 1209 squares is the most likely correct number[sm=thumbup.gif]

Rcpilot

My Feedback: (78)

Last GP ARF I built was the 33% Pitts. [:'(]

And it will be the last one. I swore that I'd never buy another GP ARF and I have no reason to change that opinion. Maybe if somebody at our field had one and I could look at it up close and personal--I might change my mind. Maybe if one of you guys on RCU would take a bunch of highly detailed pics of the hardware and assembly design--I might change my mind. The design on the Pitts left me with a raw sewage taste in my mouth and I'm not putting myself through that again. I've heard people say that the new GP ARFs are better quality. But I'm having a hard time believing it. They said the Pitts was a nice plane too.

If this new Extra from GP has 1209 squares and weighs in around 14.75lbs--16lbs --- it might fly IMAC pretty decent.

My World Models 80" Extra 300S is 80" with 1275 squares. It weighs in at 15.75 pounds and flies IMAC pretty good. The wing loading is just too much for good 3D. It does a little 3D. It'll hover and do a harrier. But it won't do a wall without snapping out.

BTerry

My Feedback: (8)

RCP, you are correct. The Pitts was sub-par. The newer planes are significantly better!

MIXMASTER

My Feedback: (15)

At 80" wing & 15 lbs +, too heavy for good 3-D, not the right size for a 50cc engine, too heavy for a 1.60 glow. This is a bad size/weight IMO. If a 50cc size wont fit in your car, get a smaller size that is light enough for a glow engine & still have light wing loading. I have flown a GP Yak 80" w/OS 1.60. Not exactly sure what the weight was but I liked the performance, it would prop hang so I dont think it was much over 12lbs.

BTerry

My Feedback: (8)

The wing span has little to do with qualification for 3D, however the shorter span will certainly roll faster.

The important thing to remember is the wing area is 1209 in^2, which isn't far behind the Aeroworks Extra 260 at 1275 in^2 (87" ws, 77" fuse) and is in fact greater than the GP Yak, which is 1138 in^2. Of course the GP Extra has a longer fuse (79.5" ws, 77" fuse) than the AW and weighs 2# less than the aeroworks, and I think the AW Extra is a decent 3D plane.

In fact most 50cc planes are between 1180 and 1350 in^2 area, but for the ExtremeFlight planes which are around 1430 - 1450 in^2.

You are absolutely correct it would be marginal on an OS 1.60, expecting the weight will be in the 13.5 - 14# range. My Extra Soucy 300S weighed around 12.5# empty, had great vertical, and would hover on the OS 1.60. Pullout was marginal, but vertical penetration (from fast level flight) was pretty good.

MIXMASTER

My Feedback: (15)

I was in this size & weight once, its not a great place to be IMO. Too heavy for glow(for a great running glow any way), too light for a 50cc engine. Most 40cc available are as heavy as the DA50. I f you go with a 30cc & pipe,you might get close but end up spending as much as a good 50cc class plane. If it was for me, I'd go a little smaller, .90-1.20 & OS 1.20AX, YS 1.10. It would fit in the car, have good thrust -weight. Just IMHO. I did have an Ultra RC Giles 74" wing w/Brison 40cc @ 12lbs. Power,wing loading wasnt too bad, but the engine was not good enough for hardcore 3-D. In retrospect, maybe the OS 1.60 would have been the way to go, would have been in 11lb range.

BTerry

My Feedback: (8)

My point is the new GP Extra is BIG airplane, it just has a short wing span. It is longer than most 50cc planes and the wing area, which is the MOST important thing, should be sufficient, maybe just a touch on the smaller side. It just has short and fat wings instead of long skinny wings.

AirTech

My Feedback: (18)

Well..... this discussion on the positive or negative merits of this model are academic to me at this time. I just purchase one to replace my GP CAP 232 (which bit the dust a week ago) and it seems to me that powered with the proper engine this may prove to be a very good entry level IMAC model. The fuse seems very light but sturdy enough to endure the occasional bungled landing. So far the only one thing I find is way too heavy is the aluminum tube joiner. It looks like it came out of a plumbers supply stock. At 12 and 5/8 ounces is way to heavy mostly due to the wail thickness being approximately 1/8". The problem with replacing the tube is that it measures 1/64" smaller than 7/8". That means that if one purchase a 7/8" O.D. composite tube it may need to be sanded down 1/64"in order to make it fit.

I am planning to power this model with an Evolution 45GX and hope to keep the total weight around 14 Lbs. I will post more info as my build goes along.

Cap232tain

My Feedback: (1)

Did you check graphtech. They may make you what you need. Don't blame you for replacing the fence post wing tube. Have the GP Cap also, very stable plane.

Cap232tain

My Feedback: (1)

Do you know anyone with a lathe. Might make it easier than sanding.

Cap232tain

My Feedback: (1)

Is that about 20mm? If so take a look
http://www.graphtechrcshop.com/produ...&categoryId=24

JOHNS3D

My Feedback: (5)

well.......dont wait and get the Extra 300 from Aeroworks.

AirTech

My Feedback: (18)

Thanks a million for the info. I am sure the best fit will be the [link=http://www.graphtechrcshop.com/product.sc?productId=123&categoryId=25]#603 7/8" x 30" x .035" Carbon Tube[/link]. The provided tube measures exactly 22.1 mm which is the same as .875 in or 7/8". This carbon graphite tube costs $49.99 but I will give it a shot and will let you know if it fits.

Appreciate the Graphtech link anyhow, thank you.

DLEVETT

My Feedback: (13)

Thanks for checking it out.
I,m interested in seeing if this wingtube is an option to save 8-9 ozs over the stock one.

Dave

Cap232tain

My Feedback: (1)

Let us know how it works out. Looks like you'll save at least a 1/2 pound.

AirTech

My Feedback: (18)

Is there anyone out there finished putting this this plane together??

I am almost done with mine and just finished doing some preliminary balancing. So far it seems to be way nose heavy. I am using an Evolution 45GX up front, the radio tray located in the aft position and the two elevator servos mounted on the locations for the rudder servos (most aft position). At 5 1/4" it needs a little over 6 ounces as far back as possible. I may be able to reduce some of this dead-weight by moving the ignition battery (a 2400mAh nickel metal hydride) to the radio tray but there is the danger of induced RMI being in close proximity to the receiver and the Rx battery. I can also try to lighten the ignition battery by using a 2200mAh Li Ion. My last option would be to move the dual pull-pull servos to the rear.

If anyone have gone so far please let me know of any suggestions.

skillet92

Air tech I put both my Rudder and Elevator servos in the rear to get it to balance and I am using a DL 50 with 23x8 JXF prop. I put both my batteries under the turttle deck on a plate i glued in place. Hope this helps.

AirTech

My Feedback: (18)

Thanks, I just figured out the same.

I have already moved both my rudder servos to the tail and both of my batteries to the radio tray and it looks to be pretty well balanced. This plane seems to be quite a departure from previous Great Planes design. I owned a Wagstaff Extra and a YAK 54 and both needed extra weight in the nose to balance. This plane is much lighter overall so it must have a better win loading than previous designs.

skillet92

Air Tech How do you like the 45GX I have the same engine I am just looking for a home for it.

AirTech

My Feedback: (18)

I love my 45GX, it's just a fantastic engine for any 25% through 28% plane. For the weight it delivers almost the same power as a 50cc. No wonder Horizon quit selling them, it was too much competition for their new 50cc. The 45GX2 have the advantage of the ignition being encapsulated in epoxy like plastic, which make it sturdier.

I believe you may still buy the 45GX from [link=http://www.mvvs-canada.com/products.php?cat=2]MVVS Canada[/link] with the designation of 45IRS/MG (MG stands for Magnesium Case).

I feel the 45GX will be and excellent choice for a very light 30% plane, with a much better power to weight loading than many 50cc engines.

DLEVETT

My Feedback: (13)

I was looking for a 45GX just a few weeks ago for my GP 27% Edge 540.
The 45GX has been discontinued by MVVS since they started producing the 50GX.
Its unfortunate because the Magnesium cased 45 is a great light weight engine for the 25% to 28% planes just as Airtech stated.
I ended up getting another DA 50 and have a 3 blade Mejzilic prop for it, since I don,t need all the power and it will provide additional prop clearance.

Dave

AirTech

My Feedback: (18)

That's a real shame. The 45GX was such a good fit for 28% aerobatic models. I suppose the closest alternative will be the 40GX. The 40GX is advertised as capable of swinging a 2-blade Mejzlik 20x8 prop at 7700 rpm and should be able to power 1.80- to 2.20-sized sport and scale airplanes comfortably. The only issue with the 40GX is having the carburetor up front which will require hacking the cowl a lot more.