Originally Posted by
underfire
I dont think the 96x96 will ever be used. ATC certainly wont figure that out. Currently working with Thales to add the separation matrix to the ATC system. This will work with the flow manager for arrival, and the departure manager. The system will adjust the flow manager to affect the frequency of the arrival based on wake conditions.This will work abck through the system to enroute.
On the screen, there are 2 features, a moving dot on the approach path for intercept target, and a cone behind each ac for the min wake separation. Interesting that US based the cone is one way and it is opposite for ICAO based, go figure.
When the crew is ready for it, the adventure is much less of an adventure. Higher thrust setting and according flap setting. LHR is a natural example with the ARR speeds higher than most. I feel that this at least minimizes the wake effect.
Interestingly enough, on Sunday, DEP from SEA, in A321, hit a hell of a wake at about 300 AGL. just after rotate, rolled left then right, bouncing the whole way.. about 2 mins behind A320 sharklet. Ac was all over the place.
Currently looking at a more refined definition of simply wingspan/weight, using wing loading, as I have seen very strong wakes from smaller ac. I am looking at weight and wing area, (not simply wingspan) and wing shape. As noted before, as an example, the variable upswept geometry of an ac like the 787...
As examples: Wing area loading
A380: MTOW/845 sq m is 680 kg/ sq m
B747: MTOW / 511 sq m is 652 kg/sq m
B789: MTOW/360 sq m is 705 kg/sq m
B757: MTOW/376 sq m is 678 kg/sq m
Of course 96x96 will be used. It’s coming to LHR in the next few years.
Expectation might mean that correction is quicker and therefore requires less roll input, but the initial roll moment will still occur. That’s what is measured.
LHR arrival speed is higher? Relative to what? 160kts to 4DME is not high in my opinion. For some of our types that’s too slow