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Old 6th Aug 2008, 03:55
  #14 (permalink)  
Jaysi
 
Join Date: Jul 2008
Location: Bangkok
Age: 62
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F14 wingsweep

Airborne, the F14 wingsweep had both automatic and manual options. The mode was selected via a button on the inboard throttle; selecting up (if my memory serves me right...could be down) was auto whereby the wings moved as a function of mach number. When in the neutral position the same electronically actuated switch moved the wings forward and back as per the Tornado. In manual you could not override the mach number programming or "overstress" the wings...ie have them too far forward for the mach number. You could, however, manually sweep them all the way back whilst below the programmed mach number to look cool on the break as was the SOP (who was I too argue). The effect produced excellent vapour off the wings whilst pulling hard fully swept at 350 kts at full throttle (similar to lightning rotation take off). The jet had no SPILS (spin prevention incidence limiting system) as per the Tornado, so had to be handled carefully as the "alpha" built up rapidly. The aim was to bleed down to gear speed rolling out downwind, then put the wings forward whilst level...all good fun (and on Youtube fighter fling video).

The "handle" (used primarily on the ground) was, similarly to the Tornado, on the cockpit left hand side. It had a flat top and was recessed under a "cover" which could be lifted out of the way for operation on the ground. When recessed, the bottom of the handle, now below the panel, locked into a "cam" which connected to the switch server on the throttle and therefore to the wing motor mechanism. On the ground the wings had an "oversweep" position to save room on the carrier deck whereby the wings were pulled back overlapping the horizontal tailplane. In order to get into oversweep, you raised the handle cover and pulled the handle upwards and out of the "cam" (light came on). Then you physically pulled the handle back until a first rearward position where the tailplane was in the way. The jet sensed this and you had to move the tailplane out of the way, the handle no longer resisted the movement and went back a further inch or two into oversweep. The handle could then be pushed back down into its housing.

Hope all that makes sense. Sorry I got carried away with the earlier nostalgia...
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