How does this bird behave on a x-wind final approach with both YDs off/unserviceable?
What the lowest hright Boeing limits the use of speed brakes if arriving hot on speed?
Never had a yaw damper failure in 13 years. Since Dutch roll is a high altitude high speed issue I wouldn't expect it to be an issue on approach. And Boeing has no limitation on minimum altitude for speed brake use. The only limitation is you can not have the boards up and flaps extended in flight.
In such design (B727 in case),the outboard ailerons are utilized only during low speed regime, and high speed roll control us obtained by small inboard ailerons fir gentle maneuvres and by spoilers for HIGH RATES OF ROLL.
The outboard flaps are unlocked as the flaps extend. Boeing figured if you are extending flaps you aren't going fast. There is a spoiler mixer in one of the wheelwells. As you turn the yoke past some point (I want to say 10 degrees but am not sure) it starts bringing up the down wing spoilers to increase the roll rate. It's not just a 727 thing, 737s and 747s all have spoiler mixers.