[NSRCA-discussion] Lost Abbra

[Chris Moon]

Sorry about your crash.  What kind of battery (brand) did you use?  A 
couple of years ago I used ni-mh from Tower.  Their Hydrimax brand.  I 
almost lost a plane due to the plastic shrink wrap nearly cutting 
through the lead. Luckily I had it fail on the bench and if I wiggled 
the wire, it would work sometimes.  I cut off the wrap and was shocked 
at the construction.  It used scotch tape to hold the wires and masking 
tape to insulate the tabs from touching.  I would check that out and 
also the switch for an intermittant connection..
Chris

vicenterc at comcast.net wrote:
>
> Yes, yesterday afternoon I lost my Abbra.  I was doing the 45 degree 
> down with snap.  After the snap, I could not control the plane.  This 
> is my recollection of events:
>
>  
>
> 1. I over rotated the snap for a kittle more than 90 degrees.  It was 
> clear to me at that early stage that something was going wrong.  I 
> snapped to the right. 
>
> 2. My friend Charlie was calling for me.  He also noticed and said 
> something to put it back in position.  I told him that the plane was 
> not responding. 
>
> 3. First reaction was to give full left to get it back upright.  The 
> ailerons did not respond.  When I realized that, I tried to take it 
> out of the dive by given down elevator since was pracically in 
> inverted position.  It did not respond.  It that aptitude everything 
> goes very fast.  Finally, I tried to give up elevator but was already 
> too late.  I am aware that I applied these control input.  It was 
> clear to me that there was no reaction.  I was able to realize that I 
> didn't have control and I could not avoid the crash. 
>
> 4. I did not have time to do anything with rudder and throttle.  
> Throttle was at idle. 
>
> 5. When we checked the crash site. One aileron servo was buzzing 
> hard.  I disconnected the servo.  Therefore, my first impression that 
> the battery flew off and it got disconnected with the force of the 
> snap was not valid.
>
> 6. I took the plane home as it came from the crash.  I disconnected 
> only the ailerons servos.  I checked the radio and everything is 
> working fine.  Only two servos are not working.  The throttle servo 
> that was practically destroyed in the crash and one aileron servo that 
> the gears were stripped.  I believe that this was caused by the force 
> of the impact.  There was not evidence of flutter in the ailerons 
> before the crash or structural damage after coming out of the snap.
>
> 7.  I believe that the plane was well over stall speed after the snap. 
>  Therefore, the plane was not in stalled condition.  However, I could 
> be wrong.
>
> 7. I use JR all around with digital servos.  PCM receiver with fail 
> safe programmed to cut engine and leave the servos in the last 
> commanded position. 
>
> 8. I use 2300 mah NiMh battery (4 cells AA Sanyo).  I checked the 
> battery voltage and was at 5.15 volts after the crash.  Discharged the 
> battery and gave 1540 mah using 250mah rate.  I am planning to cycle 
> the battery with higher loads. 
>
> 9. It was very hot day.  The plane was sitting in the sun and it was 
> second fly of the day around 2:00 PM.  Easily was close to 100 oF.
>
>  
>
> At this point, I have to admit that has to be pilot error since I have 
> not been able to find a definitive cause of the crash.  It is clear 
> that the snap initiated some kind of failure.  Other pilots think that 
> the NiMh battery gave up at high currents during the snap and caused 
> the crash.  I have been flying this type of battery for two years now 
> with no problems. 
>
>  
>
> I am informing this to the group since I would like to have your 
> feedback.  If someone had a similar problem and found the cause of the 
> crash, please let me know.  I am going back to my backup plane (the 
> old hydeout).  I have a brand new Abbra so need to put it together.   
>
>  
>
> Thanks and have a nice day,
>
>  
>
> Vicente Bortone
>
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