DESERT OPERATIONS Med. Sea Arabian Sea Indian Ocean Persian Gulf Caspian Sea Med. Sea Persian Gulf Red Sea Arabian Sea Indian Ocean

REFERENCES FM 1-202, Environmental Flight FM 1-230, Meteorology for Army Aviators, September 1982 FM 90-3, Desert Operations, August 1993

OUTLINE Desert Weather Desert Flying Density Altitude Sand Hazards to Flight

DESERT WEATHER Temperature Max recorded: 136o F, (58o C). 160o inside a WW2 tank. Minimum temperature in Siberian and Gobi deserts dive to -50o F (-45oC). Day/night fluctuations reach as much as 72o F in the Sinai Wind Iran is known for its “wind of 120 days”. The wind blows almost constantly at velocities of up to 70 mph. Sandstorms may develop to thousands of feet high and last for several days. They may form and stop suddenly. Visibility may go from 30 miles to 30 ft. in minutes. Precipitation Lack of water is the most important single characteristic of the desert. Annual rain fall may vary from 0 to 10 inches. Severe thunderstorms may cause flash flooding.

ACCLIMATIZATION Significant acclimatization can be attained in 4-5 days Full acclimatization takes 7-14 days , with 2-3 hours per day of exercise in the heat. Acclimatization does not reduce, and may increase water intake

DESERT FLYING

DENSITY ALTITUDE Pressure altitude corrected for non-standard temperature. Altitude at which your aircraft will perform at. As DA increases-------air density decreases

DENSITY ALTITUDE As we increase in altitude-----the pressure around us decreases At sea level/standard day (15oC.) 29.92 in = 14.7 psi. At 18,000ft = 7.0psi. As temperature increases-----the density (thickness) of the air decreases. (air molecules move further apart.)

DENSITY ALTITUDE FL 180 Sea Level = Air Molecules

Effects of DA on aircraft performance? Reduced horsepower (Torque) available. As DA incr. - air molecules spread out - less air going into the engine = less horsepower (Torque) being produced. Reduced wing efficiency Less air molecules acting on the wings to produce lift.

RESULTS Increased takeoff roll Reduced climb performance (ft./min.) Increased landing distance (higher TAS, higher GS) Decrease in the “excess power available” Aircraft response----more sluggish Deceleration effects (ability to slow down, and not fall through)

What to do about it Plan ahead-----ppc, understand how DA will affect aircraft performance. ANTICIPATE!!!

Sand and the aircraft Engines/blades [blade erosion,wear on engine components(particle separator, filters,inlet and turbine blades)] higher than normal oil temperatures Avionics electricity will attract the dust overheat of the black boxes lead acid batteries more susceptible to overheating in the desert

HAZARDS TO FLIGHT Sandstorms Altitudes up to 10,000 feet Near zero visibility High winds

AIRCRAFT OPERATIONS Engine TGT High TGT during engine start Avionics High humidity can subject electronics equipment to malfunction due to corrosion

QUESTIONS?? NORTH CAROLINA NATIONAL GUARD ?