The weather and my schedule got together and I finally got a chance to fly my X-250. The flight was incredible! I haven't flown anything more aerobatic than a Zagi before, and this was just plain fun. I didn't use full throttle very much, and didn't need to. I probably ought to use a smaller prop, but nothing felt over-heated on landing.

Specs: SR Batteries X-250 (auw 31.4 oz), Jeti Phasor 15/4, 8xCP1300, 9x6 prop in the future.

I had some trouble with the prop "mowing the lawn" on takeoff, so I will go to bigger wheels and a smaller prop.

I was impressed that the plane still had reasonable glide, even as overweight as I had built it. This is my first foray into thrust=weight, and I think I like it.

Bruce,

Very nice. How long are your flight times, approximately, and how much vertical performance. Not looking to hover but would like to go vertical for a little while.

Also, what kind of modifications did you have to make to get the motor into the model? I assume you're running direct drive?

Thanks so much.

Curtis

I'm not really sure about flight times.
I'm not a good judge fro vertical preformance. The plane was capable of climbing straight up as long as I could hold it that way, but my fingers need some steadying...

I'm running direct drive. I added a piece of aluminum sheet bent to follow the standard motor mounts and screw into the bottom teo blot holes. I used a short piece of 2-56 threaded on both ends bent around the back of the motor and screwed from underneath.

(Credit where credit is due: the engine mount came from discussions with the DEAF Saturday Night build session brain trust (Jim Bourke, Fitz Walker, Chris Vanderbilt and Mike Goodlett that night.)

I am attaching a couple of the bottom that should help.

I also needed to build the hatch up 1/4" so the ESC fit on top of the battery. There may be a better way to make it all fit, but that works for me.

Here's a picture of the top.

I have been working on the same mod to my X-250, but I don't have room for the battery and connectors without moving the servos, which I haven't gotten around to.

Did you have to move the servos back?

What configuration is the battery pack. Mine is 2 x 4 cell sticks. This fits, but just barely.

Leonard

I wish I had moved the servos back a bit. I added quite a bit of nose weight with the larger motor. While the plane balances with the battery pack as far back as it can go, I'd prefer to have some flexibility.

The battery pack is a 2x4 cell stick, like you described. I cheated and made the hatch a little taller so the ESC and connectors fit on top of the battery. I traced the hatch in 1/4" balsa, then cut a large rectangle out of the middle of the balsa. That's where the ESC fits. (I also used two pairs of rare earth magnets to close the whole thing down, but that's not the question. )

Hopefully the attached picture will clear up what I'm trying to say. If I'm still not making sense, let me know.

Curtis,

It occurred to me that while my flying may not be able to say wether this setup will hover (yet , I plan to practice and learn ), I do believe it will. When I was testing it, I held the airplane vertically over my head while a friend kicked in the throttle. The plane was pulling up with some force, so I assume it has the power to hover. I can't answer wether it has the control surfaces and balance and such to hover. I expect it to do good verticals. I am hoping to use this plane to learn some areobatics.

Bruce

I finally got everything to fit and balance without moving the servos. I just put the ESC in the canopy.

Leonard

I solved the servo problem by mounting them "upside down" within the same area so that the bottoms of the servos face towards the canopy. This allowed me full access to the battery compartment for the --get this- SR 2400 8 cell battery pack! It fits exactly within the battery compartment space - but this requires that you carefully balance the plane with the thought in mind that you won't be able to "shift" the battery for any further balance adjustments... I'm flying the Jeti 15/4 as well with a 10/6 prop. I also removed the old landing gear wire and added a slightly stiffer version and made it another 1" longer to accomodate the larger prop. This has worked well. I also re-inforced the landing gear around the area that the main gear attach point at the wing prior to building this plane since I've been down "that" road too many times... I've flown this baby on 20 mph+ days which requires pretty much full throttle - but I sure get a lot of eye-brow raising at the "gas" club as I zip past(!) the glow planes (at least for the first 5 minutes)....I will probably always have an X-250 in my inventory as it's such a fun plane and easy to fix...

Brucemc,

Motocalc shows over 34 amps with 8xCP1300's, Jeti 15/4 and a 9x6 prop!!! 2min, 10secs flight time. Thrust 29ozs, speed 54mph.

This is way too much amperage for a CP-1300. Have you checked your setup with a Whattmeter?

Originally posted by ChrisD
Brucemc,

Motocalc shows over 34 amps with 8xCP1300's, Jeti 15/4 and a 9x6 prop!!! 2min, 10secs flight time. Thrust 29ozs, speed 54mph.

This is way too much amperage for a CP-1300. Have you checked your setup with a Whattmeter?

Why? They might get somewhat hot if run full throttle for the duration, but there are plenty of people using these cells over 30A static. Many report that zapping does help in this range though.

Well, it seemed like it worked. I hadn't run a wattmeter on it. I'm unlikely to now, either. I lost orientation tonight and ended up in a pond. I failed to locate the motor.

I'm not sure what to do with it now, I lost the Phasor and the front of the fuselage. I'll stick the remaining bits in the closet for a few weeks and then decide how repairable it is. That'll give it time to dry out, and me time to look at it objectively.

Bruce

Bad luck Bruce.

Its hard when you put a lot of work into a plane and lose it early. Makes you wonder why you bother. Looked like a nice setup.

Bruce,

Try dragging the pond with a big magnet if you can get access with a raft or canoe. You should be able to locate the approximate area you came down in. How deep was the pond?


Chris

The pond is about four feet deep where the plane was floating. It is a run-off pond, with some really gross water and many signs saying "Fishing, Wading and Swimming Prohibited." I guess I could try the magnet, I don't really have access to a boat, but I bet I know someone who does.