Could winds of up to 150 km/h impact the structural loads on a Boeing 777?
Could winds of up to 150 km/h impact the structural loads on the B777-200LR?


Not at all.

The dynamic pressures on the plane depend on the plane's velocity with respect to the air, not the ground speed.

Flying in 150 km/h tailwind is the same as flying with no wind, the plane's indicated and true airspeeds won't be affected. True airspeed is the plane's velocity inside the fast moving wind tube.

Since the jet stream itself is moving, it just moves the plane with it. With the added bonus of extra ground speed, or if you're the pilot, a dreaded return flight—unless you can avoid the now headwind, usually they are avoided for the Pacific and Atlantic routes, not as often for elsewhere.

Here's a 1200 km/h subsonic flight: Jet Stream Blasts BA Plane Across Atlantic in Record Time