PPRuNe Forums - View Single Post - MAX’s Return Delayed by FAA Reevaluation of 737 Safety Procedures
Old 11th Jun 2019, 21:03
  #343 (permalink)  
gums
 
Join Date: Jun 2009
Location: florida
Age: 81
Posts: 1,610
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Salute!

Thanks, Flight. I am thinking more of the 'bus reversion control laws, especially "direct". My understanding may have been contaminated by many discussions on the 447 Tech Log. But as you revert to lower and lower modes you might have to trim unless you wish to hold the stick out of the neutral position, right?

Our pitch law was not corrected for aircraft attitude like the bus, so a neutral stick force was what ever you had trimmed using the small wheel or the coolie hat on the stick grip. So the Thunderbird slot trims slightly less than one gee so he has good back stick “feel”. Maybe the Wingies do that too, so I’ll have to ask one. Some of our A2A guys trimmed for zero gee in order to unload and run without holding forward pressure. I even showed studs a loop by running trim all the way - about 3.5 gee. Then we did a hands off loop and watched all the limiters work (protections for you bus drivers).

I still wanna know how the bus control laws and zero mechanical feedback can be certified, but the 737 has to have “more AoA with more back pressure”. So this thing is more than yoke force, huh? Looks like borderline pitch moment problems and no motor thrust below the wings a significant contribution.

Gums sends.....

Last edited by gums; 12th Jun 2019 at 16:58. Reason: clarification and still open for critique
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