From: sharpes@c-17igp Date: 29 Mar 93 12:27:53 PST References: 1
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> email@example.com (Jonathan Thornburg) writes: >A final point: We had some discussion in this newsgroup a few >months ago on in-flight use of spoilers. As I recall, the consensus >seemed to be that they're used for roll control, but not usually for lift >dumping as such. The C-17 uses spoilers at least six ways, one of which is roll control, another being, of course, ground spoilers. Spoilers are symmterically deflected with flaps in the cruise configuration for speedbrakes (an average of 14 degrees spoilers and 8 degrees of flap at max deflection). The outboard spoiler is coupled to the ailerons for precise speed control while under the tanker (it's gonna be a sweet flyin' thing!). During landing approach, spoilers are coupled to the throttles to take out the engine response time delay and, lastly, spoilers are used to enhance ground effects (yes, enhance ground effects! It's called SAGE - Spoiler Enhanced Ground Effects). When the Globemaster III is making a steep approach (about 5 degrees glidepath), the spoilers are uprigged nine degrees. At the appropriate height, the spoilers retract and the lift they dumped comes back to reduce sink rate. _____________ Dan | "Opinions expressed Sharpes | are mine alone, and _|_ not another's"