View Full Version : NG ETOPS controlling factor

Pin Head
5th Oct 2015, 02:00

When certified the NG is 180mins ETOPS. Is this because of the cargo fire suppression factor or is it something else?

I thought it would be only 60mins, based on the duration that the battery can give you in the event of double generator failure or does Boeing deem this as very very unlikely, hence the cargo fire extinguisher path.



No Fly Zone
5th Oct 2015, 14:23
This is ONLY a guess, but I think, "Something Else." Cargo fire suppression duration time can be enhanced -if necessary - to achieve ETOPS or extended ETOPS permissions, if/when a carrier wishes to spend the bucks. For cargo fire suppression it not a whole lot more than how much (volume/time) inert diplacement gas is carried. and how it is dispensed. (Of course there is more, but that's the biggie.) There ARE other concerns for ETOPS operations (737? you said??) beyond 60 minutes, but they are more than a bit complicated. Perhaps because of its relatively modest size, until recently the B737 was not a serious contender for extended ETOPS operations. Other considerations include an enhanced maintenance schedule and a proved history of reliability. As the most frequently sold, used and flown transport-class airplane in AV history, I'd guess that the properly equipped, individual B73 is not difficult to certify for extended ETOPS operations. Proof: Several carriers operate the B73 from the Left Coast to Hawaii, several times every day. So... while extended cargo fire suppression is one concern, there are others. The B73 series CAN be equipped for and can qualify for extended ETOPS operations.

5th Oct 2015, 14:27
Company said our 737NG's are not 180 ETOPS certified.

Pin Head
5th Oct 2015, 16:49
Thanks guys. Just looking big picture really. If you don't have rafts then straight away you cant do 180min.

Spooky 2
5th Oct 2015, 17:17
The 737G cannot be certified beyond 180 minutes. You need to have the APU running between your ETOPS entry and exit points unless your on a special approval for an APU maintenance program in which case you do not need it to be running. As other have said there is a lot more to this than what is obvious. The fire suppression is the limiting factor.

Many airlines fly the NG between the west coast of the US and PHNL which requires 180' authority.