Originally Posted by
chewing4gum
I am very interested in this topic and have other questions:.
You'll find aircraft refueling is very regulated so the issues you mention should not happen if those regulations, rules, and laws are followed. However, as does happen, people do not follow that guidance or have an equipment failure resulting in a fire. For reference here are 2 examples of that guidance:
IATA and
US DoI.
But to answer your questions:
What happens for example, if the grounding point of the aircraft or refueling vehicle no longer has any electrical conductivity (corrosion / incorrect installation ) or the bonding cable is broken, to what extent is there still a risk of fire or if, for example, the cable is attached to a painted surface?
>>The possibility of a fire increases if the refueling system bonding cables are compromised. As to what extent depends on the conditions and circumstances.
What happens if the cable comes loose during refueling or does a cable only have to be connected at the beginning of refueling to compensate for the potential difference?
>>Bonding cable(s) must remain attached before, during, and after the actual refueling ops.
How often do such fires occur?
>>Not often but they do occur. However, the reason they dont is because most people follow the appropriate guidance and maintain their refueling equipment per that guidance.
What is more problematic jet or avgas?
>>AVGAS.
You always read that fuels are becoming safer and if I remember correctly you "never" hear of any such incidents that lead to fires?
>>You never hear of them as they're more an "industry" issue than a general public headline. As to fuels being "safer", I guess that is subjective to the person. If a fuel can burn in an engine it can burn outside an engine.
In short, does this grounding during refueling serve as a safety device to prevent fires - during refueling - or does grounding have any other safety relevance?
>>Prevent fires during refueling process. But bonding aircraft is also used during a number of maintenance operations as well.
What about the electrical systems on board? Or is that irrelevant?
>>Depends on the situation. If there is an empty fuel tank/cell and a fuel pump electrically shorts and produces a spark then boom. Same with using a cordless drill around or in fuel cells.
Originally Posted by
Pilot DAR
I'm not aware of an aircraft fire resulting from eclectically discharge during fueling.
There have been a few fires due to static discharge. There are a number of reports and references on them. Heres
one.
He'd had an airplane catch fire in the hangar (before he was my client) and they pushed it out while on fire, to save everything else.
FYI: there are a number of aircraft OEM procedures that include bonding aircraft to earth prior to performing maintenance even in a hangar. We had ground points in the hangar floor for this at the old day job.