AFRL Demonstrates Near-Instantaneous Low-Spool Power Extraction Published June 18, 2008 By Thomas Brown, AFRL/RZOP Propulsion Directorate WRIGHT-PATTERSON AIR FORCE BASE, Ohio -- Engineers from AFRL and industry partner Pratt & Whitney demonstrated a near-instantaneous low-spool power extraction capability as part of the Versatile Affordable Advanced Turbine Engine program. This successful effort marks the first in a series of planned demonstrations geared towards advancing state-of-the-art propulsion technology. Specifically, the demonstrations are designed to elevate the technology readiness level of an advanced power management system capable of delivering the relatively high levels of transient power extraction that future aircraft will demand. This initial demonstration, which employed a Pratt & Whitney JT15D engine, afforded AFRL engineers the opportunity to explore engine operability as large (270 kW, or approximately 360 hp), nearly instantaneous electrical power loads were pulled directly from the engine's low-pressure spool without the use of a gearbox. As observed, use of the excess power available in the engine's low-pressure spool offers an efficient and integrated solution--one that characterizes a key capacity to rapidly model--and subsequently realize--significant levels of power extraction from a propulsion engine. This advanced capability will benefit a number of future vehicles, including high-altitude intelligence, surveillance, and reconnaissance platforms; directed energy weapons; advanced fighters; and long-range strike aircraft.