Reply #25: SPRAY SYSTEMS

[seemslikeadream]

Six Modular Aerial Spray Systems (MASS) are available at the 910 AW to conduct aerial spray missions.

Each system can be configured with up to four 500 gallon tanks for a total volume of 2000 gallons.



USAF C-130 MODULAR AERIAL SPRAY SYSTEM (MASS)

The Aircraft. Four C-130H aircraft are modified to perform aerial application. Modifications consist mostly of ULV and LV wing line installation and electrical modifications.

b. Spray System. The MASS is built by Lockheed/Conair. One of the major design criteria of the MASS was that it had to be a "roll-on/roll-off" system allowing the aircraft to be reconfigured for spray or airlift in under an hour. To accommodate the Roll-on/Roll-off design, the full MASS is designed in 3 modules, each attached to modified standard (463L) aircraft cargo pallets. The operators console, pumps, catwalks, and cradles for flush and chemical tanks are all secured to these modified pallets. The pallets lock into the C-130's dual rail system. Once the MASS is loaded, interconnecting plumbing and electrical circuits tie the MASS modules together. To contain any spillage of spray materials, a 1.5" lip (drip pan) surrounds the pallets. The dry weight of the MASS is ca. 10,500 lbs.

(1) Module 1 . All loading, mixing, spray controls, tank flushing and boom purging procedures can be performed by Spray Operators from the control panel on Module 1. Fluid transfer between tanks for mixing, recirculation and spray operations is accomplished using electro-pneumatic actuators which control the opening and closing of butterfly and diverter valves. Module 1 also contains all the MASS pumps. Three centrifugal pumps provide output pressure for mixing, transferring, recirculation and spraying for LV and HV missions. Depending on the flow rate desired, the Operator can control each of the pumps individually. Two gear driven pumps are used to provide pressure for flushing and ULV systems. A 220 gallon aluminum flush materials tank is also located on Module 1. This tank stores the flushing agents used to clean the chemical tanks and associated system components (main sump, ULV sump, wing and fuselage filtering systems, wing lines and booms). Upon completion of a spray sortie, the flush system consisting of a tank, pumps, and filtering equipment rinses the entire system followed by air purging the material over the target area.

(2) Modules 2 and 3. The MASS may be configured to use either the first two or all three modules depending on mission requirements. Modules 2 and 3 each contain two 500 gallon tanks and all the associated valves and venting systems. The number 2 module has tanks constructed from stainless steel for handling corrosive spray materials. The number 3 module is constructed of strong light aluminum to save on system weight. Modules 1 and 2 together are generally used for ULV space sprays. While modules 1 and 2 can be used for LV or even HV applications, these type application rates are generally used with the full 3 module system.

(a) Wing Booms:

1 Ultra-Low Volume (ULV). Wing booms for ULV applications are constructed of stainless steel and mounted on the outboard portion of the C-130's wing. Each boom has 25 nozzle sites (50 total) and operate at flow rates of 0-60 gallons per minute with a maximum pressure of 100 PSI.

2 Low Volume (LV). For low-volume missions, an option is to add another section of boom, constructed of aluminum, added inboard of the ULV booms and connected by a manual butterfly valve. This configuration adds an additional 42 nozzle sites for a total of 92 (46 per side) and accommodates flow rates of 60-600 gallons per minute. The fuselage booms, as explained in the next paragraph, can be equipped with 36 nozzles (18 per side). The fuselage nozzles can also be used alone or simultaneously with the wing booms. Maximum pressure is 100 PSI.

3 High Volume (HV). The high-volume booms consist of a cradle assembly used to support three inch pipes which extend perpendicular to the aircraft out the rear paratroop doors. The high volume booms come in two lengths. One boom is six feet long and the other is ten feet. Nozzles can be spaced six inches apart with nozzle sites on both the top and bottom. Each boom has holes for a maximum of 18 nozzle sites. This system can also be used in conjunction with the wing booms if a wider swath width is desired.

4 Ultra-High-Volume (UHV). This configuration is used to apply more than 10 gallons per acre with a narrow swath. The UHV system uses the fuselage booms (as with HV), but uses a single unique diffuser nozzle oriented straight back into the airstream. Each diffuser nozzle is equipped with a check valve to prevent leaking. The UHV booms are used when large droplets (>1000 µm) and a narrow swath width (< 50 feet) is required.

(4) Loading. All chemical loading is totally enclosed, and all fumes are vented outside the aircraft. MASS chemical loading into the flush and chemical tanks can be accomplished 3 ways:

(a) External Pump. A gasoline-powered pump can be used when done in conjunction with ground loading station. Spray materials are filtered into the MASS main sump and into the tanks via tank outlet valves.

(b) Ground Loading Station. The MASS loading station with its probe and loading hoses can be used to suck materials from the chemical drums directly into the top of the 500 gallon MASS tanks.

(c) Gear-Driven Pump. For corrosive materials, the ULV system can be used to load chemical with its own gear-driven pump and its associated loading hoses and drum probes, attached ground loading hoses and a drum probe.
http://www.afrc.af.mil/910aw/aerial%20spray/aerialspray/system.htm