Helicopter operations and pilot training in a desert environment requires an aviator to understand the limitations of the aircraft and how visual aspects and personal stress contribute to the challenges of flying. The US Military gained a great deal of information both from the successes and from the failures of Desert Storm/Desert Shield resulting in advanced training and new technology.
Desert Helicopter Operations: Military Specific
A typical desert environment is unpredictable, potentially violent, and does not follow any particular terrain model. Weather conditions consist of extreme highs, sandstorms, and fluctuating wind speeds; making flight operations extremely unsafe for aviators without adequate training. Since Desert Storm/Desert Shield, the United States Military has taken the experiences and mistakes that were made and used them to improve desert training for its future aviators. This training benefits all sectors of civilian, commercial, and public aviation. Yet even with experience, desert operations can still catch the most experienced aviator off guard; making it utterly important that aviators without experience have the knowledge to overcome the worst scenario. The most important factors for an aviator to understand in desert operations are the environmental effects on the aircraft, visual illusions and effects during flight, and the different kinds of stress experienced during flight. Environmental Effects on Aircraft
When operating within a desert environment, considerations must be taken to include the effects of extreme temperatures and its direct relation to aircraft performance. Extreme temperatures are the greatest power-limiting factor and are one of the leading causes for aircraft malfunction in a desert environment. Flight physics show that when there is an increase in air temperature there will be a decrease in air density. A decrease in air density ultimately means less air to create lift and less air to cool the engine. In this condition, a helicopter’s performance is limited by decreased maximum payloads and lowered maximum torque availability; prohibiting normal maneuverability. Most of this can be managed through training, the effective use of power management, and ultimately experience. The majority of aircraft accidents are a result of pilot error even though malfunctions do occur. In the military sector where operations are commonly flown between 80 and 200 feet above the highest obstacle, aircraft malfunction coupled with a pilot error is deadly. In low-level flights, the pilot has a limited amount of time to react to aircraft malfunction or environment change. Some of the more common solutions are to fly at higher altitudes to allow more time for reaction and/or slower airspeeds so as not to push maximum torque availability. Aircraft Malfunctions
Some of the prominent aircraft malfunctions consist of electrical problems, instrument misreading, over heating engines, or a loss in turbine compression. All of which can be caused by extreme heat and sand. In the desert environment, sand is the root cause for most high aircraft maintenance costs. Most of this damage occurs when the sand is ingested through the turbine. It acts like sand paper as it brushes against internal surfaces. Over time, sand abrasion will alter the aerodynamics of internal airfoils; resulting in a loss of engine efficiency, overall performance, and eventually end in a catastrophic engine failure. Over heating can cause similar problems when there is inadequate cooling or when the engine is over torqued. A report published by Pratt and Whitney in 2006 demonstrated that sand abrasion is a potential factor in turbine overheating. Research has shown that in some cases where the leading edge of airfoils reached extreme temperatures, sand was more likely to melt and adhere to the surface. These “hot spots” within the turbine decreases the service life. Further research indicates that six hours of...