Originally Posted by
ElNull
If Boeing believed that discharging a second bottle would be useful (after the evacuation had already started), then why didn’t they include this step in the engine fire on ground checklist?
If evacuation is already in progress, it surely makes more sense to have the step to fire the second bottle in the Evacuation NNC rather than having to go back to the Engine Fire on Ground NNC for that step?
Discharging of the second bottle used to be the memory item (on the 737 at least), but that usually delayed the decision to evacuate the aircraft, while waiting 30 seconds, then discharging the second bottle, then waiting if it had any effect. That is why NTSB recommended that Boeing develops the new checklist, which now redirects you to Evacuation NNC before firing the second bottle, and you fire the second bottle only while people are already jumping down the slides.