Eclipse Glitch

Graueradler

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Graueradler
System battery below 23 V but Start battery OK. Owner intends to start engine to charge system battery. Result - engine running with no way to shut it down. Don't know the systems but from observations - engine running disconnects GPU plug. System bus will not close on low voltage battery hence no controls. Engine does not respond to shutdown command. Have to remove panel on noxe with many screws to access battery. As soon as charger is connected to battey, engine shuts down. Owner now has a better knowledge of his systems.

Wasn't there an incident with low voltage that led to questions about a certification review on the Eclipse?
 
Yes. I'd have to do a lot of digging to find it. Sounds like it still is an issue.
I believe John Deakin explained that about a year ago. He recommended an APU start among other things.

Best,

Dave
 
Now that is one weird electrical system design.
Does the Eclipse even have an APU? Or did you mean GPU? On the two types I know if the battery bus is below about 16v you can only bench recharge. Neither a GPU nor an engine generator output can get to the batteries.
 
Lance: I'd have to look. They strongly discourage battery starts. I don't know if they call the ground start unit an APU or something else, but it is an axillary unit IIRC. I think, I recall John Deakin talking about the FBO having to provide the unit but that was awhile ago and I'm really not keeping current on that plane anymore. I can ask one of the fellas that flies one if it's important.

Best,

Dave
 
Wow. That's a weird system, IMHO.

I wondered why the Eclipses at Wings always have a start cart around. Now I know.
 
IIRC, King Air min for cart start is 20v.

Now that is one weird electrical system design.
Does the Eclipse even have an APU? Or did you mean GPU? On the two types I know if the battery bus is below about 16v you can only bench recharge. Neither a GPU nor an engine generator output can get to the batteries.
 
Appears to me to be a case of blame the operator for a bad design, imho. Almost like a bug they don't have a good fix for.

When Eclipse brought the prototype to Sun-n-Fun for the first time many years ago they requested a start cart to be on hand for departure. I assumed it was for starting; I never occured to me it was a contigency for shutting down.

They did a battery start, though; we never plugged in. They did seem a bit anxious during the whole evolution.

 
Appears to me to be a case of blame the operator for a bad design, imho. Almost like a bug they don't have a good fix for.
Agree. Probably realized it too far along in the process and fixing it isn't financially feasible. I don't see why you would design a system knowing that flaw throughout the process.
 
They will be chasing stuff like this for 5 years, if any of the airplanes last that long. The cram-down certification caper they pulled off was a farce, and with nobody around to handle the smoke-and-mirror routine, they will eventually come to light and (hopefully) be fixed with minimum damage or peril to the people involved. That bulletin was amazing, but indicative of their attitude throughout the process.

Agree. Probably realized it too far along in the process and fixing it isn't financially feasible. I don't see why you would design a system knowing that flaw throughout the process.
 
How do better-designed jets handle this situation? Don't let the engine start in the first place?
 
The difference seems to be the concept of separate start batteries and system batteries without any logic as to the effect of differing voltages during a ground start. I think in most normal jets the avionics and the starter will run off the same batteries. I wonder why Eclipse uses separate battery systems.
 
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