Old 14th Jul 2019, 22:05
  #31 (permalink)  
Join Date: Nov 2015
Location: Paisley, Florida USA
Posts: 112
Originally Posted by FullWings View Post
I'm not a chemist but I was under the impression that the exact opposite was the case: the whole effectiveness of halon-like suppressants comes from their ability to interfere with combustion processes at the atomic level, once broken down by heat. The cooling/smothering effects are welcome but secondary...

See: SKYbrary - Halon Fire Extinguishers
That is correct, FullWings. In a previous life, 35+ years ago, I was a fire protection engineer, and your above explanation was the then accepted understanding of Halon's interaction with the combustion process. Lower extinguishing concentrations of Halon are not lethal to Human Beings since Halon is not an atmosphere (oxgen) displacing substance such as is CO2.

Over the years, I've read many accident reports and have noted an all too frequent lack of timely communication of a problem between cockpit crew and cabin crew and vise-versa. It seems that all too often a serious problem that is revealed by looking out a cabin window is not communicated to the cockpit in a timely fashion. This may be a holdover from the "old days" when cabin crew were reluctant to call the cockpit's attention to a problem out of concern of distracting the attention of the cockpit crew. For example, I recall several instances of decompression or slowly falling cabin pressure that actuated the passenger oxygen masks, but the cabin crew never notified the cockpit crew that the masks had dropped. Anyway, hopefully things are improving with the current emphasis on Crew Resource Management (CRM). I think it is indicative that, in the beginning, CRM was Cockpit Resource Management, but people soon realized that both cabin and cockpit crews must work together in an emergency.

As a reminder of how quickly a ground fire can destroy an aircraft, here's a short video of the China Airlines Flt 120 ground fire that destroyed a B-737-800 on the ground at Naha, Airport, Okinawa on 20 August 2007

The link:


P.S. The fire was the result of a fuel tank breach that occurred when a loose bolt, improperly installed during a maintenance procedure, was forced through the web of the forward wing spar upon slat retraction.

Last edited by capngrog; 14th Jul 2019 at 22:13. Reason: Add information
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