Another 787 electrical/smoke incident (on ground)

[RR_NDB]

Your questions

Chris Scott

To this non-engineer, various questions arise. Was the APU running; and – if so – for how long, and had it started at the first attempt? Had there been any previous problems with the APU? Did the cleaners have to call for the mechanics, or were they already on board? Were the mechanics present to advise the firemen?

As for the system itself, does anyone know for certain if the APU battery is recharged from the aircraft’s main electrical system (effectively), or is there some kind of autonomous charging circuit? Is there enough space on that rack for a different kind of battery (e.g., NiCad) that would be man enough to replace this Li-ion one? And would the recharging system have to be changed?

A good environmental control of the cells (temperature and voltage monitoring) would guarantee the pack operates properly. Minimizing risks of "runways".

Certainly the recharger receives power from the APU or from the System. Probably the same recharger.

The size very probably will not be enough for a NiCd of similar capacity.

The recharging system certainly is completely different.

Would be interesting to know whether this battery fire/explosion occurred under load, or under recharge.

Probably the pack was still being recharged or completed it.


I started to comment on this serious issue in previous post.