gade600sdi

Just finished my Formula 1 Sundowner this weekend and flew 3 flights with Evolution 26GX. My problem is I have it balanced right on the book marks (I think 3 1/4" which is the mid point of the range given) and if flies fine, but it wont taxi. I broke two 16-8 props on taxi because the tail keeps popping up. I am flying on a mowed grass club field that is rolled so the surface is smooth but not perfect. Nobody has trouble at this field with bumps or anything like that.

How can I fix this? I have a little lead on the nose, about 2 ounces of lead left. I pulled a little off so far. I am using the stock 3.5" wheels up front and the stock 1.25" tailwheel. So far I have $65 lost from two broken props and a broken cowl from the back end popping up and wanting to flip over on a taxi.

Its almost like they have the gears back too far. Any way to fix this condition? If I add tail weight I will be tail heavy.

Lifer

My Feedback: (1)

Are the landing gears swept to the rear? If so, can the gear be reversed so there is a sweep to the front? Ideally, the axles should be directly below the leading edge of the wing when viewed from directly above.

You also have the option of bending a new set of gears yourself from the appropriate thickness of aluminum. Some cutting and measuring will be required but a custom gear will give you the ground handling you desire.

Best of Luck!

maukaonyx

You can shim the back edge of the gear mount so that it basically moves your axles forward. You can also move your balance point further back but still in the range for the recommended CG, as long as YOU feel comfortable with how the plane handles in the air. Bigger tires are still an option. Have you checked to be sure the tires roll freely on the axle? Friction there can cause noseovers. We assume you must be holding full up as you taxi? Fly when the grass has just been mowed or ask the mower to cut even lower if it won't hurt the grass condition. When we fly warbirds at my field, we have to ensure the field was just mowed the day before...I mow so it gets done. Use an MAS or APC prop so you don't break all those wooden props. Just my 2 cents worth...can you tell I fly on grass? Jon

Lifer

My Feedback: (1)

All of those ideas will work, but when you shim the gear, it does add drag bye way of more frontal area. It will help, though.

gade600sdi

THanks for the inputs. I am wondering how much you can actually make the axle forward by shimming the gear, would only be a very small amount it would put the gears forward. Yes I am certainly taxiing with full up elevator, even switching to high rate. I am balanced right in the middle of the range, but have removed some nose lead, so I am now in the "AFT" CG range and it still does it. I dont like using plastic props just to avoid breaking, that is not fixing the problem. The problem is the tail pops up. The gear is straight down almost, possibly 1/16" swept back.

Here is what I am going to do. 1. Install 4" wheels instead of 3.5" to help rolling and raise the front more. 2. reverse the gear so maybe I get 1/8" farther forward with the wheel centers 3. install a 1" tailwheel instead of the supplied 1.25" to lower the tail more. 4. continue to try to take a little more of the lead off the nose, or maybe leave that go and add a segment or two to the tail and see how she flies.

If the above doesnt work, I'm thinking of making aluminum extensions to move the axles 1" farther forward and bolting them into the existing axle hole and using the existing wheel pant bolt holes for "anti-rotation" pins in my extensions.

rc300xs

I had the same problem. I found that using max rate for ground handling and giving quick shots of throttle worked better. I also moved the fuel tank way back so the rear of the tank was next to the wing tube. I moved the CG back a tiny wee bit as well (but not too much!). Next I took off the landing gear and bend them ever so slightly to raise the nose. All of this combined helped out greatly.

Also make sure your wheels aren't binding on the wheel pants and that the wheels turn freely.

gade600sdi

Yes RC300 I found that using high rate for taxiing, and also taxiing faster was better than a slow taxi...but still not enough. I like your idea about bending the gears slightly too I will add that to my little bag of tricks. Thanks.

Speedyman

My Feedback: (3)

I am just finishing up my Sundowner with a Mokie 210. Would like to know what is the best prop for this setup and I am trying to fing antoher sundowner Fomula 1 NIB.
And help in findiing one be appriciated
Cell # 256-679-1115
Thanks ART.........................

cavandish

I shimmed my gear with vee shaped block, you do not need to lift the back up very far to get the wheels forward 3/4 inch.
As for increasing drag, ARE YOU SERIOUS !
I would not recommend a wooden prop with this plane, go for smaller diameter and more pitch, the APC props will take light ground strikes without very little damage, I had a piped BGX and found a 16x15 APC to be the best.
you will get used to the ground handling, stick with this bird, it is a lot of fun, just be aware of you stall speed in slow turns !