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Old 11th Aug 2017, 00:27
  #1585 (permalink)  
Concours77
 
Join Date: Nov 2016
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Neutral Stick

I wrestled for some time trying to understand Bonin's chronic "Aft Stick".
First it was tempting to blame his poor seat position, the inappropriate placement of armrest for the controlling hand, (right arm), or turbulence.

Now, I believe Bonin simply did not allow for the aircraft's AUTOMATIC Nose Up Trim from the THS. Neither did he allow for the Nose UP moment of the fuselage due to full thrust from the engines. At Stall, having lost outboard lift from the wings, the Nose went further up, and he was chasing a stick neutral point that was decidedly forward of neutral as he knew (expected) it to be. Was it the result of startling aerodynamics, design, and lack of Stall training? I believe he descended all the way without adjusting for these factors. This has been in the back of my mind since the wreck was discovered and the final report.

Whatever prompted Bonin's "But I have been holding aft stick for some time..."? I believe whatever possible solution Robert had in mind, Bonin had already thought to try. Why did Robert (emphatically) demand "Climb, Climb, Climb..." After Bonin responds, Commandant demands "NO NO NO, don't climb". Robert may have meant "ascend". Bonin may have heard: "pull, pull......" This exchange is fraught with mystery, and sadness; confusion is so apparent.....

So, the aircraft has just taught Bonin not to recognize the aero at Stall due to its inherent stability, and to misjudge the quadrants of the stick, ("the aircraft cannot Stall"), and the piece de resistance? StallStallStall when forward stick is applied and indicated airspeed exceeds sixty knots... Counterintuitive, poor design, and fatal.

Plenty of room under these circumstances to allow for some retrospective slack in the armchair judgment that is traditional in these threads. At least insofar as the stick is concerned. This is not sympathy nor defense, it is the truth as I see it.

There's more.....

Poor weather brief, "triple redundant ADIRUs" that simultaneously fail due to known but unmitigated design flaws and failure to replace the Pitot components pursuant to regulatory and mandatory orders.

At gums post #1397.... (not that long ago)

"- The jet has really great aero to get into a stall without obvious shaking, buffet, wing rock and so forth."

From my post #1403...

"gums,

"- The jet has really great aero to get into a stall without obvious shaking, buffet, wing rock and so forth."

I think that is intended as a compliment.... I think it is actually an indictment.

Last edited by Concours77; 11th Aug 2017 at 00:56.
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