EFFECTS ON EQUIPMENT
TRAFFICABILITY: Terrain varies from nearly flat, with high trafficability, to lava beds and salt marshes, with little or no trafficability. DRIVERS, be well trained in judging terrain over which you are driving so that you can select the best method of overcoming the varying conditions you will encounter.
Track vehicles are best suited for desert operations. Wheel vehicles may be acceptable because they will go many places that track vehicles can't go; however, their much lower average speed in poor terrain may be unacceptable during some operations. Vehicles should be equipped with extra fan belts, tires and other items likely to malfunction, together with tow ropes (if not equipped with a winch), extra water cans, and desert camouflage nets. Air recognition panels, signal mirrors, and a tarpaulin for crew anti-sun protections are very useful.
The harsh environment requires a high standard of maintenance which may have to be performed well away from specialized support personnel. OPERATORS, be fully trained in operating and maintaining your equipment. Some types of terrain can have a severe effect on suspension and transmission systems, especially those of wheel vehicles. Tanks tend to throw tracks on rocks. The unit PLL of tires should be considerably increased as sand temperatures of 165 degrees F are extremely detrimental to rubber and weaken resistance to sharp rocks and plant spines. Items affected by mileage, such as wheels, steering, track wedge bolts, sprocket nuts, and transmission shafts, must be checked for undue wear when completing before, during, and after operation maintenance.
WHEELED VEHICLES: On rocky deserts, the M54 5-ton truck is prone to air hydraulic cylinder failure and power-steering leaks. Tire consumption is very high, so all vehicles must carry one spare tire or preferably two spare tires, and the unit PLL of tires must increase considerably. About one of every three vehicles should carry jumper cables to provide for servicing dead batteries.
VEHICLES: Vehicle cooling systems and lubrication systems are interdependent, and malfunction by one will rapidly place the other under severe strain. All types of engines are apt to overheat to some degree, leading to excessive wear and, ultimately, leaking oil seals in the power packs. Commanders should be aware which vehicle types are prone to excessive overheating and ensure that extra care is applied to their maintenance. Temperature gauges will read between 10 to 20 degrees hotter than normal. Don't panic if your average operating temperature is 180 degrees and when operating your vehicle the gauge shows 200 degrees. Monitor the gauge. If the temperature keeps rising, put the vehicle in neutral and rev the engine up to approximately 1,200 RMPs until the gauge drops back down. You must check oil levels to ensure that levels are what is required (too high may be as bad as too low), that seals are not leaking, and that oil consumption is not higher than normal. You must keep radiators and air flow areas around engines clean and free of debris and other obstructions, and water-cooled engines should be fitted with condensers to avoid waste as steam through the overflow pipe. Cooling systems' hoses must be kept tight (a drip a second is 7 gallons in 24 hours). OPERATORS, do not remove hood side panels from engine compartments while the engine is running as this will cause turbulence, leading to ineffective cooling.
BATTERIES: Batteries do not hold their charge efficiently in intense heat. You will have to adjust the battery specific gravity (sg) to this environment. The unit can either adjust its electrolyte to 1.2000 to 1.225 sg or obtain sulfuric acid, electrolyte, with an sg of 1.2085 - 1.2185. It may also be necessary to adjust the battery sg to compensate for cold nights. TM 9-6140-100-12 contains information concerning these procedures. Batteries must be kept full but not overfilled, and a reserve of distilled water should be carried. Air vents must be kept clean or vapors may build up pressure and cause the battery to explode. Voltage regulators should be set at the lower end of the specifications.
PRESSURE: Severe heat increases pressure in closed, pressurized systems, such as the M2 Fire Burner unit, and increases the volume of liquids. Care must be exercised to ensure that working pressure of all equipment is within safety limits, and caution must be exercised when removing items such as filler caps.
AMMUNITION: You must keep ammunition away from direct heat and sunlight. If it can be held by bare hands, it is safe to fire. White phosphorus ammunition filler tends to liquefy at temperatures over 111 degrees F, which will cause unstable flight unless projectiles are stored in an upright position.
COMMUNICATION EQUIPMENT: Dust affects communication equipment such as amplifiers and radio teletype sets. The latter, especially, is prone to damage due to its oil lubrication, so dust covers should be used whenever possible. Some receiver-transmitters have ventilating ports and channels that can get clogged with dust. These must be checked regularly and kept clean to prevent overheating.
RADIOS: All radios, regardless of type, must be kept COOL and CLEAN. They must be placed in the shade whenever possible and in a ventilated area. If water is available, lay a damp towel on top of the radios, making sure that the air vents are not blocked. RADIO OPERATORS, obtain a paint brush that you can use to keep your radios clean.
Desert tactics require dispersion, but the environment is likely to degrade transmission ranges. This degradation is most likely to occur in the hottest part of the day. If you start to lose contact, especially if noon is approaching, you must have alternate ways to communicate.
Some radios automatically switch on their second blower fan if their temperature rises too high, which normally only happens in temperate climates when they are transmitting. Amplifiers are liable to severely overheat and burn out. Such equipment should be turned on only when necessary (they do not affect receiving), as they take approximately 90 seconds to reach the operating mode.
THERMAL CUTOUTS: Some items of equipment are fitted with thermal cutouts, which open circuit breakers when equipment begins to overheat.
MEDICAL SUPPLIES: During movement and at operation sites where extremely hot temperatures exist, continuous protection is necessary for medical items and supplies which deteriorate rapidly.
RADIANT LIGHT: Radiant light or its heat effects may be detrimental to plastics, lubricants, pressurized gases, some chemicals, and infrared tracking and guidance systems. Items like C02 fire extinguishers, M13 decontamination and re-impregnating kits, and missiles must be kept out of constant direct sunlight. Optics have been known to discolor under direct sunlight (although this is unusual), so it is wise to minimize their exposure to the sun's rays.
DUST AND SAND: Dust and sand are probably the greatest danger to the efficient functioning of equipment in the desert. It is almost impossible to avoid particles settling on moving parts and acting as an abrasive.
MECHANICAL EQUIPMENT: Lubrication must be the correct viscosity for the temperature and kept to the absolute minimum in the case of exposed or semi-exposed moving parts. Sand mixed with oil forms an abrasive paste. Lubrication fittings are critical items and should be checked frequently. Teflon bearings require constant inspection to ensure that the coating is not being removed. Maintenance of engines is critical due to the strong possibility of sand or dust entering the cylinders or their moving parts when the equipment is stripped. It is essential to have screens against flying sand (which will also provide shade for mechanics). MECHANICS, you must keep your tools clean and out of the direct sunlight, as hot tools are hot to handle. The use of high pressure hoses may force sand and dust into seals and bearings.
FILTRATION: It takes relatively little dirt to block a fuel line, and compression-ignition engines depend on clean air. The abrasive effect of sand in oil has already been mentioned.
Air cleaners of every type of equipment must be examined and cleaned at frequent intervals. The exact interval depends on the operating conditions but should be at least daily.
Filters must be used when refueling any type of vehicle, and the gap between the nozzle and the fuel tank filler must be kept covered. Fuel filters will require frequent cleaning. Oil filters will need replacement more frequently than usual. Engine oil will require changing more often than in temperate climates.
ELECTRICAL INSULATION: Wind-blown sand and grit will damage electrical wire insulation over a period of time. All cables that are likely to become worn should be protected with tape before insulation becomes worn. Sand will also find its way into parts of items such as "spaghetti cord" plus, either preventing electrical contact or making it impossible to join the plus together. You should carry a brush, such as an old toothbrush, to clean out such items before they are joined. Additionally, a pencil eraser will work wonders on antenna connections.
WEAPONS: Weapons may become clogged or missiles jammed on launching rails due to dust and sand accumulation. Sand or dust clogged barrels can lead to inbore detonation. Muzzles must be kept covered by a thin cover so an explosive projectile can be fired through the cover without risk of explosion. Working parts of weapons must have the absolute minimum of lubrication. It may even be preferable to have them totally dry.
OPTICS: All optics are affected by blowing sand which will gradually degrade their performance due to small pitting and scratches. Guard against buildup of dust on optics, which may not be apparent until the low-light performance has substantially deteriorated. It may be advisable to keep optics covered with some type of plastic wrap until operations determine their use. Whenever possible, use the soft brush in the BII to clean optics. If possible, use a low air pressure system to blow all sand out before wiping or dusting to prevent scratching of the lens.
SAND ACCUMULATION: Sand and dirt can easily accumulate in hull bottoms of armored vehicles. This accumulation, combined with condensation or oil, can cause jamming of control linkages. Sand at the air bleeder valve can inhibit heat from escaping from the transmission and result in damage to the transmission. The operator's checks and services increase in importance in this environment.
HUMIDITY: Some deserts are humid. Where this is the case, humidity plus heat encourages rust on bare metal parts and mold in enclosed spaces such as optics. Bare metal surfaces on equipment not needed for immediate use must be kept clean and very lightly lubricated. Items such as optics must be stored in dehydrated conditions using dessicants; those being used should be kept where air can circulate around them.
CONDENSATION: In deserts with relatively high dew levels and high humidity, overnight condensation can occur wherever surfaces, such as metal, are exposed to air that is warmer. This condensation can affect items such as optics, fuel lines, and air tanks. Fuel lines should be drained both night and mornings, and optics should be cleaned frequently. Weapons, even if not lubricated, will accumulate sand and dirt due to condensation--another reason for daily cleaning.
EXPANSION AND CONTRACTION: Air and all fluids expand and contract according to temperature. If you inflate tires to correct pressure during the cool night, they may burst during the heat of the day. If fuel tanks are filled to the brim at night, they will overflow at midday. Servicing these items during the heat of the day can result in under-pressures, overheating of tires, and a lack of endurance if the fuel tanks were not filled to their correct levels. Find the midpoint of the temperature range during the day and check pressures and fuel levels at that time of the day. Locate the fill line on fuel tanks and do not overfill.
INSTRUMENTS: Precision instruments, such as range finders, may require adjustment several times during the day depending on the temperature variation.
STATIC ELECTRICITY: Static electricity is prevalent in the desert. It is caused by dry air coupled with an inability to ground electric charges due to dryness of the terrain. It is particularly likely with aircraft or vehicles having no conductor contact with the ground. The difference in electrical potential between separate materials may cause a spark between them, and if flammable gases are present, they may explode and cause a fire. A metal circuit must be made between tankers and vehicles being refueled; contact must be maintained during refueling, and the equipment must be grounded. A further hazard of static electricity is with helicopter sling loads. The hook should be allowed to touch the ground before being loaded and a load grounded before being unhooked. It is also necessary to turn off all switches, uncouple electrical connectors, and ground all electrically operated weapons systems before re-arming.
Environmental Effects on Personnnel
Desert Operations, Saudi Arabia Lessons Learned
|Join the GlobalSecurity.org mailing list|