Mon May 03, 2021 12:39 pm #1844619
Iceman wrote:As technically interesting as this project may be, some parts of the company’s text trouble me.the crew were able to safeguard the battery and safely release hydrogen from the onboard tanks, following ZeroAvia safety protocol;.
If the fuel cells weren’t compromised then why vent the fuel into a post-crash, potentially explosive atmosphere ? That would appear to be a bit like someone saying that there were no holes in an AVGAS fuel tank, but we’ll drain all of the fuel out anyway. It would read much better to me if they’d said that they’d left it to the formal AAIB investigators before disturbing the accident scene and altering crucial accident investigation evidence.
Likely because of the unique combustion properties of hydrogen. If there was a hairline failure in the pressure vessels and a leak which did ignite, then the hydrogen flame would be undetectable to the naked eye. This could have been a major hazard to a potential post crash recovery and as there are no consequences to venting to atmosphere, then it would seem the prudent thing to do. I would imagine this is SOP for them, rather a controlled release than an accident later on!
At facilities with hydrogen gas, IR flame detectors are required and straw brooms (burns visible upon contact with a hydrogen flame plume) are used to detect otherwise invisible fires.