A hard day at the field...

lobstermash

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Today was a stunning Canberra Spring day. I've been playing with a few of my planes and trying to fly some that haven't seen the air for a while, so today's menu was:

1. Extra 260 - I flew this without landing gear and a 10x4.7 prop last time. I put the gear on it and an 11x5 to get some extra oomph. Glydr hadn't seen this plane before.

2. Parkjet - I tried flying it a few weeks ago but one of the motor connector wires burnt off... again. I wanted to have some proper speed runs this time.

3. Red Eagle wing - I've been playing with this for a potential FPV plane. I didn't have an FPV camera to put on it, so I went with a keychain and wanted to put some air time into it.

4. FPV Raptor - I brought this to show off to glydr. Love flying it.

First thing that went up was the Extra. Took off nicely, got a few clicks of trim and then I gave it more throttle. The prop started making a weird hollow sound - I don't remember that noise with the 10" prop... Anyhow, it was flying nicely, but I thought I should bring it in and double check that prop and that nothing had come loose. My first run at the runway (cricket pitch) I came in too hot, and instead of gliding nicely the plane was bumping around all over the place! I went around for another attempt and put it down nicely, though a little hot, about halfway down the runway. My wife decided to walk in front of it and the wing hit her leg, sending the nose and rest of the plane in different directions. Was a pretty clean break, but a sad end to an otherwise nice landing!

Next plane to go up was the wing. Glydr was flying his Bonsai, and I was going to try and get some shots of it in the air, but his battery fell out and by the time he found it I'd landed. On landing, I noticed that the motor was a little loose. Two of the screws were only being held into the ply mount by the hot glue I'd used to sure up the connection!

Third I put up the Parkjet. Glydr launched it for me and I got in a couple of speed runs before the plane emitted some magic smoke. I still had control but lost the motor, which it turned out had burned.

I was scared to put the Raptor up, but thankfully all went without a hitch. A confidence saver at the end of the day. Phew. Haven't had so many repairs needed in one day for a loooong time.
 

colorex

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Wow... that's not-so-cool... I crashed my own tricopter the other day and I have no more spare props, so I'll have to wait for a loong time before I fix it.
 

earthsciteach

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I hate days like that! Yesterday, my pristine Air Wing Surfer had its first "incident." The wind was 15-20 mph so I was pretty excited to get the plane up and play around. I did a little happy dance as I was going out.

The Surfer, as expected, handled the wind beautifully! I'm sure I was wearing a huge smile the whole time. I'd just climbed to altitude and chopped the throttle. The plane was hovering nicely in the steady wind. I pushed the nose forward to gain airspeed, then pulled back into a beautiful loop. As she came around to the vertical, I kept the nose pointed at the ground. When I pulled back on the stick, the wings separated with a pretty amazing sound. The fuselage lawn darted while the wings fluttered across the field. It was hilarious.

The nose was only slightly crunched. It straightened out nicely in some hot water. I need to find the servo extension that is somewhere behind my house, though.
 

glydr

How many letters do we ge
Some people were watching at the edge of the field while we were flying. I was flying my parkjet and remarked to LM- "I bet they want to see a crash, you better hurry up and get something in the air!"

Just as those words left my lips the parkjet got a bit low and skidded along the grass damaging an elevon!

(served me right!)

A good day all the same!
 

lobstermash

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Haha, yeah, all planes repaired and I'm ready for more. Loving the spring weather... Here's a taste of what's to come today:

parkjet.jpg

Glad to hear I'm not the only one crashing!
 

lobstermash

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I'm hoping to get some video, as I suspect there'll be a lipo or ESC fire... I don't have a watt meter
 

earthsciteach

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Bah, watt meters are for people who don't want to see their airplanes go up in smoke. Way to man up, Lobster!
 

lobstermash

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Haha, thanks teach. I've just returned from a session. Took the Parkjet and the Extra. Parkjet was first off the rank. The ESC struggled a little to keep up around half throttle, but once it got over that it ran on. I launched no worries then backed off the throttle - tried to keep the high amp runs pointing away from buildings...

I have to say... I wish I did this from the start! Not only does it look and sound cool, it's at a minimum just as fast as the 3000kv motor. I did a couple of runs and brought it down to check out the temp. As suspected, the ESC was hot. But the battery and motor were warm. I sat it aside to cool down.

I powered up the Extra and took off. The prop started making the noise again, but I think it's just the sound of the air getting chopped as it bounces out of the cowl. When climbing vertically, it doesn't make the noise. When flying straight, it sounds like a full scale plane. I think I'm starting to like it. There's a horrendous amount of torque with this prop but so much power! I also tried some 3d aerobatics, but I'm not skilled enough to hover (I'm pretty sure it'd to it in the right hands) and it won't knife edge at all. So I tried to teach myself rolling harriers, but I need way more practice. I then had a go at some snap rolls and spins. I think this thing's going to get a lot more regular flights...

The ESC had cooled enough for some more speed runs, but as I spooled the parkjet up for takeoff the ESC smoked. I unplugged everything quickly so it didn't do any further damage. I reckon a 30A Plush is next.
 

glydr

How many letters do we ge
That's magic smoke every session from that parkjet!

Sorry to miss your message, was out with the kids and have been doing the usual long weekend things (change oil in the mower and do the lawns!).
 

lobstermash

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I'm about to do the lawns. Let me know if you want to go for some speed runs this arvo. I've installed the Plush and fired it up - working nicely.
 

lobstermash

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Lawns done. While mowing I remembered sticking the EDF unit on a Watt meter last time I was in Adelaide. It was an old Watt meter that only went to 30A (I mean, ten years ago who'd have thought of a motor that could draw 30A!!!) and this unit maxed it out. We stuck the unit on a flycat, but the force of air was too much for the elevator, which was in the middle of its airflow. I hope the Plush is up for the punishment. That's 360 Watts for those wondering...
 
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colorex

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Hey lobstermash - how's the parkjet in durability? I've only seen broken motor mounts and burnt motors so far...
 

lobstermash

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The EPO is very soft, especially on the control surfaces. The fibreglass motor mount is all but useless and the 3000kv motor is technically 2s only, but will run on 3s if you're careful enough. Crash wise, I've had some doozies but they've all been quite fixable.

For the fun factor alone it's worth having. Just get the kit and use your own electronics. On 3s I think the 'stock' motor is running at pretty low efficiency, so a beefier 2500kv motor would probably deliver at least the same speed and power with a 5x5 prop with lower amps and less heat.
 

colorex

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The EPO is very soft, especially on the control surfaces. The fibreglass motor mount is all but useless and the 3000kv motor is technically 2s only, but will run on 3s if you're careful enough. Crash wise, I've had some doozies but they've all been quite fixable.

For the fun factor alone it's worth having. Just get the kit and use your own electronics. On 3s I think the 'stock' motor is running at pretty low efficiency, so a beefier 2500kv motor would probably deliver at least the same speed and power with a 5x5 prop with lower amps and less heat.

If you had to choose between a ParkJet kit + electronics and a RadJet 800 PNP which would you get?
 

lobstermash

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I haven't seen a Radjet in the flesh... I landed my Parkjet kit + electronics for less than $50 (I was surprised that it was cheaper than the PNF). But the price difference would be offset by having to do less to make it reliable as a regular flier. So probably the Radjet might pip it at the post. A motor upgrade to the Radjet could get it doing similar speeds.

PS you should recognise the motor on the Radjet... Same as the Bixler.
 
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lobstermash

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The Bixler is a big, draggy frame that weighs about 600g with a 2200 on board, so the kv efficiency is much lower than the no-load1900kv spec. I use a beefy 1900kv motor in my Bixler that I thought would be a direct replacement, but it's actually a lot faster and more powerful because the efficiency (actual rpm vs rated rpm) is much better.

With a small, sleek airframe, the Bixler motor should be running at much higher efficiency on the Radjet and give a resepectable top speed (at a guess, maybe 75-80mph) and vertical performance.