[crazyjoe]

Today I had a brain fart. I am flying the rcpilot katana 100cc running 6 7955s and 1 8711 for the rudder plus throttle servo. So I charged my 2 A123 2300s at the Field. I had 4 good 11 minuet flights then in the middle of my 5th flight 100 yards out doing rolling harrier 30 feet up when the motor went to fail safe. Engine went to idle and I was able to level it out when everything went dead. All i could do was watch as it glided in. Hiked out there to discover no damage to the plane. Servos were buzzing but they didn't have enough power to move. Pulled the canopy to discover I had only plugged in one battery. It read 4.5 volts and took a little over 2100 mah to charge. What a way to test how many flights I can get out of a battery.

[67fairlane]

that is known as an extreme battery test..after you saw it was alright did your butt-pucker go into fail-safe too

[Ground Pounder]

Not trying to make light of the situation but.... been there, done that about 6 weeks ago. The good news was that I only did 4 flights so I did not have to test the auto-glide function.

Been running a 2300 pack for my 100 cc ignition. Haven't bothered to charge it, uhhhh for about 2 or 3 weeks. Strange thing today, my engine would not idle back to the pits after the first flight. Wouldn't start on the second flight. The ign battery was at 4.1 volts. Seems that my dumb a$$ flight crew should have charged the battery sooner this month. I fired them and will be posting a want ad for a new, more competent flight crew.

[crazyjoe]

It landed in some rough stuff all I can say is Pilot RC makes some tough carbon gear.

[Funboy]

Whew! Thank god it's OK!

Better to be lucky than good any day!

[Airbike]

Well, A123's DO give a notice that they are about to dive off the discharge cliff. BUT you better be listening cuz it is a SHORT notice.

I've had two instances where I over-discharged my A123's, both under different circumstances but totally my fault for not managing my flight times and charge status of the battery.

I'll share in hopes that other A123 users learn from my mistakes instead of repeating them.

I almost killed my 3M Compy Flag Scheme Extra one day when I flew longer than normal flights and more manuevers than normal (lots of rolling flight, meaning lots of elev, rud, ail, everything) I noticed that the rudder seemed a bit soft like it had lost torque or something, I did a couple more manuevers and the plane was like 30' above the runway but in a level attitude. For some reason I just let the plane settle into a landing a little farther down the runway. I tried to turn it around when I saw that the elevators would not even go up anymore. I think I was probably within 10 seconds to doom...
The Spektrum Rx did not lock out and the voltage was 4.5 or so. Both 2300 packs took about 2195 to recharge.


The other instance was on my 100cc Yak that I just got from Showtime. I got it ready to fly and used a 2s2p 4600 A123 pack from my Sukhoi that was sold. Well, I didn't recharge the pack and I had forgotten how much time was used on the last flights I had with the Sukhoi. I am using the IBEF ignition battery eliminator thingy on this plane so it is additional load on the battery. During the 4th flight of the day, in the middle of a rolling harrier loop, I heard the engine hiccup when I gave it some throttle. I landed immediately. The engine would not throttle up but sputtered around a bit, then it quit (I suppose the IBEF cutting out is a warning to those that are running without an ignition battery). Voltage was 5.2 or so and the pack took 4250 to recharge. Luckily, the Spektrum Rx did not lock out.

The moral of the stories for A123 batteries: When in doubt, Recharge or swap out the battery(ies). Or double them up. Be aware of your state of charge. Use a Weasel mah counter or keep good track of the flight times.
Remember that IMAC uses a lot less Rx battery (since we're tryin' to be smooth...) but wild aggressive 3D, especially if high speeds are involved, uses up the juice in a hurry.

Take care.

[camss69]

Originally Posted by Ground Pounder

Not trying to make light of the situation but.... been there, done that about 6 weeks ago. The good news was that I only did 4 flights so I did not have to test the auto-glide function.

Been running a 2300 pack for my 100 cc ignition. Haven't bothered to charge it, uhhhh for about 2 or 3 weeks. Strange thing today, my engine would not idle back to the pits after the first flight. Wouldn't start on the second flight. The ign battery was at 4.1 volts. Seems that my dumb a$$ flight crew should have charged the battery sooner this month. I fired them and will be posting a want ad for a new, more competent flight crew.

I hope you fired the guy that puts gas in your plane also.

Oh yeah and that guy that was supposed to plug in your batteries....

[crazyjoe]

Originally Posted by camss69

I hope you fired the guy that puts gas in your plane also.

Oh yeah and that guy that was supposed to plug in your batteries....

I had a long talk with myself on the way home about preflight. I usually charge every 4 flights using only half my capacity. With both batteries plugged inn that is.

[Ground Pounder]

Originally Posted by camss69

I hope you fired the guy that puts gas in your plane also.

Oh yeah and that guy that was supposed to plug in your batteries....

BTW, your fired to.

If there needs to be a corporate reorganization, heads will roll.

[Buttface]

Originally Posted by crazyjoe

Today I had a brain fart. I am flying the rcpilot katana 100cc running 6 7955s and 1 8711 for the rudder plus throttle servo. So I charged my 2 A123 2300s at the Field. I had 4 good 11 minuet flights then in the middle of my 5th flight 100 yards out doing rolling harrier 30 feet up when the motor went to fail safe. Engine went to idle and I was able to level it out when everything went dead. All i could do was watch as it glided in. Hiked out there to discover no damage to the plane. Servos were buzzing but they didn't have enough power to move. Pulled the canopy to discover I had only plugged in one battery. It read 4.5 volts and took a little over 2100 mah to charge. What a way to test how many flights I can get out of a battery.

Dude I did the same exact thing with my new 40%Carden Extra 330 on the first day out with it. I was inverted 10' above the center of the run way going about 50 mph when my plane hit fail safe. I held full 3D rate aileron and it slowly rolled up right, I banked around and failsafe hit again ,got control enough to bank it around one more time to line up to the runway and Fail safe hits again....The plane glided in for a perfect landing in full fail safe !!! The surfaces drooped from their own weight upon landing. I pulled the canopy and found out that I forgot to plug both of my a123s in to the expander...DUH!!!
But I didn't get no butt pucker/pulsating anus stuff or anything like that going on..cuz I'm' just cool like DAT!

By the way that a123 batery never recovered . It had a reading of .2 v lol....dead as a door nail!