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Chosun
15th Jul 2002, 01:34
Observing IAS on gusty/bumpy approaches, with the 744 speed tape bouncing up and down like a lunatic, prompts the thought ........Are we sensing IAS in the best way? The 744 has two pitot probes, either side of the forward fuselage, and 4 main static plates, two forward and two aft. Now, why are we sensing/displaying/re-acting to IAS? Well, I guess it is to give us an idea of stall margin, and keep us away from the undershoot. But, on a 744, the wind/gust/IAS sensed at the forward fuselage, at the winglets, and half-way along the spar are all going to be different. So, my naive question, why don't we sense IAS at more points, integrate it, and show the integrated sum to the driver? That way the "bouncing tape" syndrome would be reduced, the pilot would be less re-active with thottles, and we'd have an easier life. I know that pitots are designed to grab the air before the plane disturbs it, but I still don't think we're getting a fair indication of what is really going on. I imagine an albatross is getting feedback from EVERY feather, not just one on each side of its head.........
:confused:

northwing
1st Aug 2002, 21:17
I don't knowabout Albatrosses (Albatri, Albatrosa or whatever the plural is) but if you look under the leading edge of a chicken you'll find little tufty feathers about 4 mm long at intervals spanwise. I reckon they are there to give stall warning.