Mmo of B77W??

[ERAU_Hatsune]

I saw a source says 0.87, but another says 0.89. So what is the real Mmo of B77W?

[Candido_S]

There are several factors of change of speed, I indicate to you to make your flight plan through the site www.simbief.com, all the information of your route in flight will come detailed in the plan emitted by the simbrief. there are several factors that can change the speed.

[ERAU_Hatsune]

but I think the Mmo should stay the same. not your cruise speed.

[Chatta290]

On IF I’m pretty sure it’s like Mach .87 where you would get overspeed violations so I would definitely say that I doubt it’s .89

[schyllberg]

It’s M 0.89 (http://www.boeing.com/assets/pdf/commercial/airports/acaps/777_2lr3er.pdf)

(@Heavydriver or @Yuan_Tugo can probably confirm, the document was only used a source. Can’t find the exact mention)

Edit:
Also found this, which seems pretty legit (https://www.flightglobal.com/news/articles/flight-test-boeing-777-300er-fast-and-heavy-176585/) @ERAU_Hatsune

[BennyBoy]

What’s Mmo??? Is it Mach speed becuase I thought the 777W cruised at M.84.

Or does Mmo mean maximum speed?

[Matthew]

I think it’s maxinum Mach speed though I may be wrong.

[USA007]

MMO is the same as VMO but just given in Mach numbers. Yes the MMO of the B77W is M.89

[Joeoreilly77]

Really most of the time they cruise at Mach 0.85

[Yuan_Tugo]

MMo is Maximum Mach Operating speed and is fixed. VMO varies as a function of altitude. (you can’t hit MMO at low level as VMO will be your limiting speed however at FL400 MMO will be hit before VMO)

I’ve looked through my manuals and I can’t find an defined number. It’s the start of the red over speed barbers pole if that helps!

I’ve cruised at .86 quite happily before.

[Heavydriver]

Yuan_tugo pretty much summed it all up but Mach .89 is the limit for the 300ER. 200ER is Mach .87