Etops question

[tubby linton]

What,if any modifications would have to be made to a transport category aircraft to allow it to operate to 180 mins etops ,when it is currently certified for 120 mins?
My guess would be cargo fire suppression systems.

[ampclamp]

They need to prove up the reliabilty (in flt shutdown rate) of their pwr plants first I'd say.

[The The]

Our 737's operate to 180min ETOPS.

Requirement to have APU running until ETOPS exit point.

Believe requirement due inflight APU start not sufficiently assured. That's also why leave it running from start up and not start it at ETOPS entry point.

[9.G]

tubby linton, your guess is correct. Most restrictive factor is cargo fire fighting system capabilities.