Here is an interesting fact I just learned: Each engine on a Boeing 777 has as much power as all three engines on TWO 727-200’s. That’s right, six 727 engines equals the thrust of one 777 engine. 
They’re also almost the same diameter as a 737 fuselage. 11’3" (for the GE-90-115B…the R.R. Trent is 9’4") versus 11’7" for the 737 fuselage.
Yeah, they’re huge. I lived in Seattle when they were testing those engines on the 747 prototype. At that time the 747 engines looked huge until you saw that 777 engine mounted on the 747.
You ought to see that GE90-115B up close. 
Those fan blades are something else.
Wow, what a cool picture, thanks for sharing.
Is it just me or is that 737’s gear wearing shoes and pants? Look to the left of the ‘CD’.
[quote=“damiross”]
Testing of the engine: - YouTube)
This is the GE flying Test Bed aircraft seen in the video doing GEnx testing: N747GE[/quote]
[quote=“pmbell64”]
This is the GE flying Test Bed aircraft seen in the video doing GEnx testing: N747GE
Looks like it’s testing an Etch-a-Sketch or, more likely, a Spirograph![/quote]