Rmbrush75

I have a similar problem. If I follow the tutorial exactly, the airplane will be going too fast (e.g., 230 KNOTS) at NIRSI and at every waypoint thereafter despite full speedbrakes. The airplane will never reach 206 KNOTS after NIRSI, where the tutorial says FLAPS 1 should be applied. The VNAV mode will read VNAV PTH throughout. If I add FLAPS 1 to slow to 220 KNOTS at NIRSI, the airplane will achieve the predicted speeds at NIRSI and the later waypoints, but the airplane will be too high (e.g., DES PATH UNACHIEVABLE). After adding FLAPS 1, the VNAV mode will change from VNAV PTH to VNAV SPD. I have been unable to reach both FMC predicted altitude and speed at the approach waypoints at and after NIRSI. Clear skies, no wind confirmed. I've also confirmed all flight plan entries.