Abstract:
Columbia Helicopters, Inc, (CHI) has procured several military-surplus CH-47D helicopters for use in heavy-lift operations, including fire-fighting and other external lift operations. For decades, CHI has successfully utilized Direct Visual Operational Control (DVOC) to precisely control the load at the end of a long line. The key to DVOC is the use of a bubble window at both pilot and co-pilot positions on the aircraft, which allows the pilot flying the aircraft to see the load directly. CHI designed, manufactured, tested, and qualified a replacement cockpit door to hold a bubble window in the CH-47D. The new doorframe is made of carbon-fiber epoxy composite, holds an 18-inch-deep bubble window in the upper section, and holds a sliding ventilation window in the lower section. An abbreviated composite building block test was completed to prove the structure, and flight test was used to determine the optimal flight attitude to evacuate the cockpit of smoke.