PPRuNe Forums - View Single Post - AF 447 Thread No. 7
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Old 27th December 2011 | 16:37
  #737 (permalink)  
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Fighter pilot mafia speaks, huh?

yeah, Retired, Mach, Wolf, Smilin', et al.

I can't figure out how much aileron-rudder-interconnect (ARI) there is in the various "alternate" laws from looking at my skimpy 'bus manuals. Maybe Retired or A33 can enlighten us?

The Normal law appears to have not only a great ARI function for rolling into a turn, and also has an appropriate pitch input to make a level turn if stick pitch input is neutral.

Same question about the "damper" functions. I thot the 'bus retained the dampers regardless of mode, even "direct". This would resemble what we fighter pukes flew with since the 60's. And it definitely helped mitigate PIO's and other bad things.

Viper dampers NEVER cut out, but ARI cut out when one main gear WOW switch was compressed, hence no "wing low" landing, you landed in a crab. Otherwise, the rudder position that had been manually commanded for the slip went off the wall upon touchdown ( and we tested this for ourselves, heh heh). You don't need air data or inertial system data for the function, just some rate gyros embedded in the flight control computers via hardware/firmware or independent rate/gee sensors feeding the computer(s). In other words, we had no need to have a "basic" computer to filter and use all the external inputs, like the ADRIU the 'bus seems to rely upon.

I am not sure we saw but a glimpse of PIO with respect to the roll commands, so won't join that opinion. Same for inadvertant pitch inputs, as looks like they were intentional because "the aircraft won't let you stall" mentality.
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