No abstract

Studies have been made on several wing leading-edge modifications applicable at present to single-engine light aircraft, which produce stabilizing vortices at stall and beyond. These vortices have the effect of fixing the stall pattern of the wing such that the various portions of the wing upper surface stall nearly symmetrically. The lift coefficient produced is maintained at a high level to angles of attack significantly above the stall angle of the unmodified wing, and the divergence in roll usually is reduced to a controllable level, it is hypothesized that these characteristics will help prevent inadvertent spin entry after a stall. Results are presented from recent largescale wind-tunnel tests of a typical light aircraft, both with and without the modifications. The data indicate that the static stall and poststall characteristics of this aircraft, in a typical landing-approach condition, are noticeably improved when a suitable leading-edge modification is employed; and also that no appreciable aerodynamic penalties are evident in the normal flight envelope.

No abstract

This is a US. Government work and is not copyrightable under U.S.C. 105.

Integration of the Hard Disk Controller (HOC) today has taken on an extensive amount of functionality. From the host interface, error correction code, disk sequencer, microprocessor(s), servo control logic, buffer controller, to the embedded memory, the HDC has become a true system on a chip. Depending on the product, embedded DRAM is used as buffering for data between the host and media and possibly for storing controller firmware. By bringing all these blocks into one chip, pin counts can be reduced and higher dataflow speeds can be obtained by decreasing the interconnect delays. However, the challenge for designers is in test and verification of the design during development and production.