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Good? Lots of flying on this sunny, fine Saturday?
Good.
Let me tell you about mine.
Took the T-Rex 500 and 12S T-Rex 600 out this morning for a bit of a thrash. 500 flew nicely, although my attempt at 3D wasn't. Then started with the 600. Oh dear...
About 2 minutes before the timer expired, the head speed went way down. OK, I thought, I'm flying it much harder than I usually do, perhaps I've just managed to drain the battery quicker than expected (and the pair of packs are from the 6S days so they aren't new). Wrong. One cell on one pack had failed and puffed and both packs were red hot. That's the end of those packs then.
So then I put my brand new pair of packs in. 2 minutes before the timer expired, the head speed was down. Oh no... but the packs were cool, the motor barely warm, the ESC only ambient temperature. Perhaps the harder flying had used more power than I expected. So I went home, and from then on things got worse.
First the pack with the puffed cell, I removed the puffed cell and found it was totally dead, I put a nail through it and it didn't even smoke let alone catch fire. Then while charging my only decent 6S pack for my 500, in my haste instead of plugging the main cables into the charger's cables, I plugged the main cables into each other. Huge flash, the connectors welded themselves together and the pack started to puff fast. I threw it outside. I had just killed a perfectly good 6S pack :-(
While waiting for my 600's remaining decent packs to charge, I decided to finish off repairing the plank (a ducted fan MiG-15). I got it all nicely back together, tested everything was working and by now I had a charged pack for the 600 too, so I decided to go fly the plank and the 600.
After a failed launch with the plank (it has this bungee launch system, it has basically 2 speeds, very fast and fall out the sky) I managed to get it in the air. It was actually flying very nicely. Then the motor just died completely. I had no control, either. No power. It was actually gliding very nicely, remaining wings level and maintaining airspeed in a steady but slow descent. I was actually quite surprised at its stability with zero power to either the motor or the servos. It would have been alright if it quit while going upwind, but it was going downwind and heading out towards the valley at considerable speed, so I kept trying the controls. Then it sprang back into life! I gave it full throttle and started turning it around so I could land, then the power suddenly failed halfway through the turn. Helplessly I watched as the bank tightened up and the nose went down, as it disappeared out of sight into the valley now with about 90 degrees of pitch down. When I reached the wreckage, it wasn't good, the nose had stuck a good couple of inches into the ground, the fuselage had crushed, both main spars on the wings were broken and the motor and fan had ripped off its mount and crushed the battery. A complete write off.
I was so frustrated I scrapped it there and then, breaking it into pieces small enough to fit in my backpack so I didn't have to do the "walk of shame" with the wreckage out of the field...
So at least I had the 600. Wrong. Seconds after taking off, the power went down on the 600 and it lost head speed so I quickly landed before it turned into a full blown auto. I checked the connections, everything good - so I thought I'd just get it into a low hover to see if I could diagnose the problem, with the Castle Cremations bursting-into-flames incidents sitting in my mind. The moment I applied power again it made a horrible graunching noise... so I shut down. Looking down on the motor, it appeared that the pinion had slipped down on its shaft, and the main gear had stripped. When I got it home I found the pinion hadn't moved at all, it had basically disintegrated about 2-3mm into the main gear - I don't know whether the main gear stripped first and the bad mesh under power then destroyed the pinion, or if the pinion started disintegrating and destroyed the main gear. I suspect the main gear went first because the teeth stripped on it are stripped the full height of the gear, but the pinion broke about 2-3mm into the main gear (so I would expect if the pinion went first it would have just stripped the bottom 3mm or so of the main gear).
So now with the remainder of the weekend being sunny, our national holiday approaching (July 5th), I have no helis to fly and no planks to fly. At least I didn't crash either of my helis.
Good.
Let me tell you about mine.
Took the T-Rex 500 and 12S T-Rex 600 out this morning for a bit of a thrash. 500 flew nicely, although my attempt at 3D wasn't. Then started with the 600. Oh dear...
About 2 minutes before the timer expired, the head speed went way down. OK, I thought, I'm flying it much harder than I usually do, perhaps I've just managed to drain the battery quicker than expected (and the pair of packs are from the 6S days so they aren't new). Wrong. One cell on one pack had failed and puffed and both packs were red hot. That's the end of those packs then.
So then I put my brand new pair of packs in. 2 minutes before the timer expired, the head speed was down. Oh no... but the packs were cool, the motor barely warm, the ESC only ambient temperature. Perhaps the harder flying had used more power than I expected. So I went home, and from then on things got worse.
First the pack with the puffed cell, I removed the puffed cell and found it was totally dead, I put a nail through it and it didn't even smoke let alone catch fire. Then while charging my only decent 6S pack for my 500, in my haste instead of plugging the main cables into the charger's cables, I plugged the main cables into each other. Huge flash, the connectors welded themselves together and the pack started to puff fast. I threw it outside. I had just killed a perfectly good 6S pack :-(
While waiting for my 600's remaining decent packs to charge, I decided to finish off repairing the plank (a ducted fan MiG-15). I got it all nicely back together, tested everything was working and by now I had a charged pack for the 600 too, so I decided to go fly the plank and the 600.
After a failed launch with the plank (it has this bungee launch system, it has basically 2 speeds, very fast and fall out the sky) I managed to get it in the air. It was actually flying very nicely. Then the motor just died completely. I had no control, either. No power. It was actually gliding very nicely, remaining wings level and maintaining airspeed in a steady but slow descent. I was actually quite surprised at its stability with zero power to either the motor or the servos. It would have been alright if it quit while going upwind, but it was going downwind and heading out towards the valley at considerable speed, so I kept trying the controls. Then it sprang back into life! I gave it full throttle and started turning it around so I could land, then the power suddenly failed halfway through the turn. Helplessly I watched as the bank tightened up and the nose went down, as it disappeared out of sight into the valley now with about 90 degrees of pitch down. When I reached the wreckage, it wasn't good, the nose had stuck a good couple of inches into the ground, the fuselage had crushed, both main spars on the wings were broken and the motor and fan had ripped off its mount and crushed the battery. A complete write off.
I was so frustrated I scrapped it there and then, breaking it into pieces small enough to fit in my backpack so I didn't have to do the "walk of shame" with the wreckage out of the field...
So at least I had the 600. Wrong. Seconds after taking off, the power went down on the 600 and it lost head speed so I quickly landed before it turned into a full blown auto. I checked the connections, everything good - so I thought I'd just get it into a low hover to see if I could diagnose the problem, with the Castle Cremations bursting-into-flames incidents sitting in my mind. The moment I applied power again it made a horrible graunching noise... so I shut down. Looking down on the motor, it appeared that the pinion had slipped down on its shaft, and the main gear had stripped. When I got it home I found the pinion hadn't moved at all, it had basically disintegrated about 2-3mm into the main gear - I don't know whether the main gear stripped first and the bad mesh under power then destroyed the pinion, or if the pinion started disintegrating and destroyed the main gear. I suspect the main gear went first because the teeth stripped on it are stripped the full height of the gear, but the pinion broke about 2-3mm into the main gear (so I would expect if the pinion went first it would have just stripped the bottom 3mm or so of the main gear).
So now with the remainder of the weekend being sunny, our national holiday approaching (July 5th), I have no helis to fly and no planks to fly. At least I didn't crash either of my helis.
and a platinum star 
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