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Old 19th June 2008 | 21:54
  #1409 (permalink)  
airfoilmod
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The simplest explanation

might involve the HP packing viscous fuel into the nozzle annulus and/or the bypass (relief circuit) while the Low side simply couldn't keep up. At this point the fact that the LP's were active would RESTRICT free flow, the alternative of suction being locked out. At some location (bearings at high side) is where the Fuel "Sheared" into dense "petals" and "voids" (cavitation). Alone, I think cavitation was insufficient to choke the supply, but briefly. At this point (when the Engines were ~1.57 EPR), I believe the coup de grace may have been introduced into the supply with an as yet undetermined combination of Resonance, Harmonics, flutter (at LP valves), and an inability of the system to "select" suction or boost. The reason I'm keen on flutter is that it would explain a halving of fuel flow during the time its cycle was "closed", against the LP port.

Re-Heat: A little too cryptic for me, sorry

rgds Airfoil

Last edited by airfoilmod; 19th June 2008 at 22:06.
 
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