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Fly Time
05-01-2008, 06:05 PM
Man I hate posting in this section! But I do it because I know you guys would rather read about someone elses misfortunes than experience it for yourself :rolleyes:

This morning before work, I decided to give my Ikarus Pitts Special Shock Flyer a test flight with a 3 cell lipo instead of the 2 cell battery I had been using. Ever since I built this plane about a month ago, I've been trying to get it set up right. At first it was underpowered and flew knife edge better than straight and level. Then I put a stronger motor in it and adjusted the thrust angle and CG, and it flew much better. It still didn't have the power I wanted, so today I traded some power for weight and installed a 3s 1300 mAh lipo. It jumped into the air not minding the extra weight one bit, and after a few minutes I had it trimmed out pretty good. I was beginning to actually enjoy this little airplane, finding it very easy to fly inverted and knife edge.

I was just starting to test my hovering skills at about 50 feet off the ground when all of a sudden I heard a little "click", and the plane nosed down! Elevator control was lost, and I didn't have the presence of mind to cut throttle until it was about 10 feet off the ground and still accelerating. The little red Pitts hit the ground at a fairly steep angle, though not straight down. From accross the field it looked to be in one piece, but as you can see by the pictures, it hit pretty hard! :eek:

The cause of the crash was pretty obvious. I used a "servo arm easy connector" to connect to the elevator pushrod, and despite knowing better, I didn't use any loctite on the nut holding the pushrod in place. The nut fell off in flight and was nowhere to be found. :o

Appropriately, I bought this plane from Hobby Lobby's weekly Crash Sale. It was pieced together very cheaply, and all of the electronics appear to be fine. It may actually fly again.

Gnascher
05-01-2008, 06:40 PM
Aw sure ... some hot glue and packing tape and you'll be ready to crash it again in no time! ;-)

buzkil
05-01-2008, 07:26 PM
Sorry to hear about your missfortune. I too have this plane but mines still under construction. Mine is going to be the 4D version. About 3 weeks ago hobby lobby had a crash sale on the power system combo so I bought one. I'm slowly piecing it together. Servos and a batt are the next to be bought. Just funds are a little low do to my upcoming vacation.
Hope your able to piece it back together.

Fly Time
05-01-2008, 07:37 PM
Sorry to hear about your missfortune. I too have this plane but mines still under construction. Mine is going to be the 4D version. About 3 weeks ago hobby lobby had a crash sale on the power system combo so I bought one. I'm slowly piecing it together. Servos and a batt are the next to be bought. Just funds are a little low do to my upcoming vacation.
Hope your able to piece it back together.
I got mine from the Crash Sale too. Decided against using the brushed motor it came with since the cost of a brushed motor ESC is about the same as a new outrunner and ESC combo. When I first walked up to it all crumpled up like that I thought it was a goner. But I'm pretty sure it will go back together. Either way no big deal because it was so cheap. Not including batteries, it cost me about $80 to get in the air using a motor and ESC combo from HeadsUpRc and a GWS Pico Rx. Everything else came out of the spare parts bin.

Sabrehawk
05-01-2008, 08:20 PM
Oooo,.......ouch Doug! Man im sorry to see and hear of crashing it, I like that little thing.
In fact I was thinking the other day that I ought to repair my flat foamie Christen Eagle and see how these two look in the air together next time were out flying together.

Well, she doesnt look much worse than mine, and mine took a nice slap to the nose on the asphalt from about 20ft up at southcenter.

Hope ya get her fixed and to see ya soon.;)

Chuck.:tc:

Fly Time
05-01-2008, 08:36 PM
Hey Chuck, if you fix yours, I will fix mine!

I think all I really need is some glue and a new prop. I'll probably add some balsa or CF to stiffen the fuselage a little around the cracks.

And a new nut for my servo connector and some loctite :rolleyes:

Fly Time
05-05-2008, 11:42 PM
I got my little Pitts bipe all patched up over the weekend using a combination of hot glue and Gorilla Glue. GG is stronger and lighter, but HG is so quick and easy! The fuselage had multiple fractures and was twisted pretty badly, so using hot glue meant I only had to hold it in position for 30 seconds and it was set. HG holds great to foam, so I'm not worried about the strength at all. It's not as perfectly straight as it was before, but with some trim adjustments I think it will fly just fine.

I didn't have the right prop (or so I thought), but I put an E-Flite 10x8E on it just to test the motor. Surprisingly, I found that it was drawing 8.5 amps on just a 2 cell lipo and pulling pretty good, so I might just try flying with this prop. I had all but given up on using a 2 cell lipo in this plane, but now I'm not so sure. :)

I would have tossed it into the air with the EF prop, but at the last minute I realized my aileron servo is stripped. I'll have to wait another few days for a replacement to arrive, but this plane will be back in the air soon!

Fly Time
05-09-2008, 12:54 AM
Aw sure ... some hot glue and packing tape and you'll be ready to crash it again in no time! ;-)
I flew my Pitts again today....
and crashed it again :o

It was a little breezy and as soon as I got it up, the wind kicked up even more. I was flying it on 2 cells and a GWS 10x4.7 SF (yep, it's orange!). With that prop I should probably be on 3 cells, and with the wind kicking up to about 12 mph my ground speed into the wind was about 1 mph. But I was having fun all the same and figured I would just run my battery down and then try switching to a prop with a little more pitch. I was doing some loops, inside and outside, and as the battery voltage began to sag I went into one too low and couldn't quite complete it in time. Busted the motor off the front but that is all (I think). Even the orange prop survived! A little epoxy and I'll be good to go.

buzkil
05-10-2008, 03:36 AM
Glad to hear that your able to breath new life into it. My build is comeing along pretty slow. I just orderd 4 servos from hobby lobby crash sale, $19 servos for $12. Couldn't pass it up. Heck if I wait long enough I'll be able to get everything that I need for it at crash sale price.:D

I got a question for you. How do you mount your Batt? Do you just wedge it in the slot or what? I have a couple of three cells with JST connectors, but there is no way they are going to fit in that slot.

Fly Time
05-10-2008, 06:01 AM
Glad to hear that your able to breath new life into it. My build is comeing along pretty slow. I just orderd 4 servos from hobby lobby crash sale, $19 servos for $12. Couldn't pass it up. Heck if I wait long enough I'll be able to get everything that I need for it at crash sale price.:D

I got a question for you. How do you mount your Batt? Do you just wedge it in the slot or what? I have a couple of three cells with JST connectors, but there is no way they are going to fit in that slot.
The slot is really just for tucking the servo wires away. I used velcro on the battery and fuselage. It mounts on the side of the fuselage pretty much at the CG, opposite side as the servos to keep it balanced laterally. I cut away some of the 45 degree angle foam strip that runs down the right side so the battery is flat against the fuselage.

buzkil
05-19-2008, 10:39 PM
Hey doug, thanks for the info on batt placment. That seemed to work out fine. It balences out pretty good both ways now. I built the fuse first then installed all the electronics. I fiugured it would be easier to do it this way so I didn't have to work around the fragile wings to install everything and get it balanced. And it was! All that's left now is to build the wings and landing gear and install them.
Mine is built as a 4d plane with the varible pitch prop. I'm going to set up 2 model memory on my controller for it. One as a plane and one as a heli. I'm not real good as a 3d pilot yet so I know 4d is still out of my leauge but I wanted it set up that way for when I am ready for it, I wouldn't have to do any mods to it. It sould be real interesting!

Angler-Hi
05-19-2008, 10:58 PM
Sorry Doug!! I'm just now seeing this thread friend. That sucks man. I hope you get her fixed up soon.

If it makes you feel any better, I went to maiden my Ultimate Bipe on Saturday with max2112 and ran out of runway, ripping the landing gear clean off and breaking the folding prop. Here's some pics to make you feel better:D

Mike

Fly Time
05-19-2008, 11:12 PM
Hey Barry, glad to hear yours is coming along. If you can find a 3-cell battery that is less than about 80 grams you will be real happy I think. Mine is a little heavy with a 100 gram battery, but it still flies fairly nicely. A little odd actually, probably due to my fiddling with the power system and thrust angles, but easy to get back down.

Mike: I appreciate the thought, but it makes me feel no better to see the pictures of you busted up bipe :o But look on the bright side: that World Models folding prop was butt ugly anyway. It needed to go! :D

Angler-Hi
05-19-2008, 11:26 PM
Hey Barry, glad to hear yours is coming along. If you can find a 3-cell battery that is less than about 80 grams you will be real happy I think. Mine is a little heavy with a 100 gram battery, but it still flies fairly nicely. A little odd actually, probably due to my fiddling with the power system and thrust angles, but easy to get back down.

Mike: I appreciate the thought, but it makes me feel no better to see the pictures of you busted up bipe :o But look on the bright side: that World Models folding prop was butt ugly anyway. It needed to go! :D

Yeah, I agree. That's why I bought an additional 10x6 APC prop instead. She'll fly again though...maybe next weekend. Good luck on getting that Pitts back in the air.

buzkil
05-19-2008, 11:32 PM
I don't know the weight of the batt, will have to look online to see if I can find it. It's a GWS 3s 1p 1300mha. The plane does feel a little heavy but I will see.

Hey mike, at least that's an easy fix. Did the same thing to my ultimate a while ago. The dreaded "stall turn" when I realized I was about to hit a pole at the end of my landing. Mine poped two holes on the bottom wing covering from the wheel pants. A little packing tape was a quik fix for that and a little epoxy gluded the the balsa back for the landing gear. Bim Bam Boom and it was flying again. As for your motor mount, they make an adjustable alluminum one that would bolt right in.

buzkil
05-19-2008, 11:34 PM
My bad, I though that was a pict of your motor mount in your hand.

buzkil
05-19-2008, 11:39 PM
Ok found the batt. It's 81 grams so it sould be fine then right?

Fly Time
05-19-2008, 11:44 PM
Yeah, I agree. That's why I bought an additional 10x6 APC prop instead. She'll fly again though...maybe next weekend. Good luck on getting that Pitts back in the air.
Oh she's back already! In fact I've crashed it at least 3 times since my first crash :rolleyes: Hey, better this one than the planes I really love!

It's pretty easy to fly, but with too heavy of a battery a bad landing breaks stuff. My latest crash was due to the prop saver scews coming loose right after take off. The prop started slipping on the shaft right as I pulled up, and she stalled and came down hard. The crash before then, I was trying to take off from thick grass in 15 mph wind. The little wheels on this plane have zero ability to roll on grass, but with the head wind all I had to do was hit the throttle and up she went. Unfortunately I probably gave her too much throttle, because it was all torque and no airspeed as I corkscrewed it right back into the ground :eek:

The fact that it was so cheap to put together makes crashing a lot easier to take. It's easy to fix too. I'll post a picture tonight, hot glue scars and all :D

Fly Time
05-19-2008, 11:50 PM
Ok found the batt. It's 81 grams so it sould be fine then right?
That should work fine. Fly it onto the ground under power because it has so little inertia when gliding.

Are you using the stock motor and prop? That prop that came with the plane has a really low pitch speed. I'm using a GWS 10x4.7 and like it better. Of course I'm using a little TP brushless motor, so you results may vary.

buzkil
05-20-2008, 01:05 AM
That should work fine. Fly it onto the ground under power because it has so little inertia when gliding.

Are you using the stock motor and prop? That prop that came with the plane has a really low pitch speed. I'm using a GWS 10x4.7 and like it better. Of course I'm using a little TP brushless motor, so you results may vary.

I'm using the ikarus recomended 4D variable prop and motor combo. Where I can adjust the pitch of the prop for forward flight or I can reverse the pitch and fly backwards. Not that I plan on flying backwards anytime soon. Not untill I get the feel for it flying forward anyway. The motor, gearbax and prop that came with the setup are still in the bag unopend.

Fly Time
05-20-2008, 04:00 AM
Here's a picture of my re-constructed Pitts Special. Or maybe I should call it the Hot Glue Special :rolleyes:

buzkil
05-20-2008, 08:50 PM
Hot dam she flies again!!!!! Nice repair job, you can hardly tell.

Fly Time
05-20-2008, 08:59 PM
Hot dam she flies again!!!!! Nice repair job, you can hardly tell.
Thanks Barry. Up close you can definately tell!

Between a combination of mechanical malfunctions and errors in judgment, I believe this is now my most-crashed airplane. :rolleyes:

I've crashed others worse - beyond repair even - but this one seems to have something go wrong just about every other flight!

buzkil
05-20-2008, 09:28 PM
Thanks Barry. Up close you can definately tell!

Between a combination of mechanical malfunctions and errors in judgment, I believe this is now my most-crashed airplane. :rolleyes:

I've crashed others worse - beyond repair even - but this one seems to have something go wrong just about every other flight!


Well I quess flying backwards is definatly out of the question then!:silly:

Fly Time
05-20-2008, 09:34 PM
Well I quess flying backwards is definatly out of the question then!:silly:
For me, yes. I'm still trying to figure out how to hover.

Actually this is a good plane to learn new skills on, which is part of the reason why I've crashed it 4 times now. It's easy to fix and the $ investment is low.

shotgunsmitty
05-20-2008, 09:44 PM
I had an RCU Bipe that I named The Gluebird. The only thing holding it together was black thread and CA. I flew it multiple times, even after an in flight wing loading failure...yeah, how do you do that on a biplane? I have witnesses, it just cracked like an egg in mid-flight. The fuse went through the bottom wing. Amazing!
I flew it numerous times after that.

But I do like the looks of that one...

buzkil
05-20-2008, 10:42 PM
Hey Doug, I think mine is going to be a little heavier than yours because I have an extra servo and the only reciever I cound find around the house was an Hitek electron 6.

Haven't started on the wings yet. Got the wheel pants and the wing struts glued together. Next on the agenda will be to do the wings. I saved them till last because cutting a 45 degree bevel on both wings and elerons take some finese and a sharp blade.

Fly Time
05-20-2008, 11:34 PM
...Next on the agenda will be to do the wings. I saved them till last because cutting a 45 degree bevel on both wings and elerons take some finese and a sharp blade.
Use some 150 grit sandpaper taped over a block of wood (or a sanding block) for the 45 degree bevel. It goes quickly, and there is no chance of an errant cut with the Exacto knife.

buzkil
05-20-2008, 11:38 PM
Thanks for the advice Doug. What I did for the tail was to sandwich the surface to be cut between 2 stagard rulers and just slid the exacto down the edge. Seemed to work pretty well. I may give the sandpaper a go just see.

buzkil
06-04-2008, 07:28 AM
Well i finally got to madien her! She is a little on the heavy side but flies pretty decent. I haven't tried any 3D yet but I don't think it will do that very well. The reason I say that is because after I did a few trimming up circuts over the house I tried to do a loop and the loop kind of fell on it's side.

The plane also needs a paved surface to land on, tried to land it on the grass and it didn't like that too well. After a few of those and the corbon rods for the landing gear started to rip the wings and the fuse, and a tear is starting to form on the fuse infront and behind the top wing. I'm going to put some packing tape on all the ripps and brace up the fuse by the top wing and see if that helps.

Other than that, the planes pretty cool, hope she last awhile!!

FlyingMonkey
06-04-2008, 01:07 PM
Here's a picture of my re-constructed Pitts Special. Or maybe I should call it the Hot Glue Special :rolleyes:



I love hot glue!

Fly Time
06-20-2008, 01:30 AM
I think I've finally crashed my Pitts for the last time :sad:

I had it out last weekend and was puzzled as usual as to why I can never seem to get this thing to track straight. It is truely a strange bird! It will do knife edge and even harriers with ease, but try to do a simple loop and it snaps out over the top. The fact that it has crashed so many times now probably has something to do with it :rolleyes:

Anyway, I was having fun making it fly weird and after 6 or 7 minutes decided to bring it down. The wind was blowing and was creating some turbulence near the ground, and I overcontrolled my final turn just over the pavement. I tried to get it back under control but ended up nosing in inverted :eek: It hit with a splat, and they guy who was flying next to me said "Oh, that didn't sound good! Is it alright?"

"I don't think so." I said with a laugh.

The fuselage was mashed badly (again), but everything else seemed fine. I could fix it with another half stick of hot glue, but last week I ordered a 3D Yak foamie from Hobby Lobby for $12, and I think I will just move the electronics over to it instead. I've had my fun with the Pitts, and now it's time for something different. Maybe this one will actually fly straight :rolleyes: