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Old 27th Jan 2002, 09:35
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john_tullamarine
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I cannot speak to the 800, but consider a related problem.

If you do any sim exercises purportedly to look at crossover handling, be aware that some of the older software may not model the 737 characteristics well in this area.

I had the interesting experience on another model of doing some pre and post mod testing when the particular operator upgraded the software for the relevant simulator. The handling pre and post mod was chalk and cheese ... the earlier software being quite unconvincing, and the later exceedingly convincing and quite like the accident reports

Blip,

I suspect that you have omitted consideration of the following ..

(a) the aerodynamic lift forces will be a function of a number of variables including airspeed and incidence as you have observed. There is no reason, though, why these forces will vary in the same way with speed due to, for instance, the different lift curve characteristics of the particular controls.

(b) however, the effect of these forces on the handling depends principally on the moments generated by those forces (rolling and yawing moments) which depend both on the force and the distance of the mean force vector from the aircraft cg.

[ 27 January 2002: Message edited by: john_tullamarine ]</p>
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