Helicopter Applications

Radial-Inflow Turbine The radial-inflow turbine, or inward-flow radial turbine, has been in use for many years. Basically a centrifugal compressor with reversed-flow and opposite rotation, the inward-flow radial turbine is used for smaller loads and over a smaller operational range than the axial turbine. Radial-inflow turbines are only now beginning to be used because little was know about them heretofore. Axial turbines have enjoyed tremendous interest due to their low frontal area, making them suited to the aircraft industiy. However, the axial machine is much longer than the radial machine, making it unsuited for certain vehicular and helicopter applications. Radial turbines are used in turbochargers and in some types of expanders. 

Yates, W.E., in "Atmospheric Transport of Sprays from Helicopter Applications in Mountainous Terrain" ... 

Postemergent helicopter application. (Photo courtesy of the Spray Drift Taskforce. With... 

Figure 100. Helicopter application of 1-ring-labeled DDT to a terrestrial study area, (a) Radio-controlled, gasoline-powered rotary applicator used to apply insecticide to study area, (b) DDT granules being applied to an old-field ecosystem. Courtesy of T. J. Peterle.

An outline of various actuation schemes has been given in Figure 2.10. On account of the efficiency with regard to the helicopter application, we will here focus the derivation of an analytic solution on the variants of twist actuation. This requires the coupled consideration of extension and torsion as well as warping and torsion of the beam. The prior is represented by the stiffness coefficient Pu in the constitutive relation and the latter by the equilibrium of Eq. (8.37a). To ease the solution, shear and bending of the beam will only be coupled with each other. This comprises the stiffness coefficients P25 and P36... 

With regard to the above discussions and with the integral blade actuation for the helicopter application in mind, as illustrated in Section 2.5, the example configuration schemes will be focused as follows ... 

The turboprop engine has a power turbine instead of the nozzle as seen in Figure 4-2. The power turbine drives the propeller. The unit shown schematically is a two-shaft unit, this enables the speed of the propeller to be better controlled, as the gasifier turbine can then operate at a nearly constant speed. Similar engines are used in helicopter drive applications and many have axial flow compressors with a last stage as a centrifugal compressor as shown in Figure 1-14. 

The methacrylic polymer remains a useful glazing material. In aircraft applications it is used extensively on aircraft which fly at speeds less than Mach 1.0. They form the familar bubble body of many helicopters. On land, acrylic sheet is useful for coach roof lights, motor cycle windscreens and in do-it yourself cabins for tractors and earth-moving equipment. Injection mouldings are frequently used for plaques on the centre of steering wheels and on some fascia panelling. 

R. L. Pinckney, Helicopter Rotor Blades, in Applications of Composite Materials, Michael J. Salkind and Geoffry S. Hollister (Editors), ASTM STP 524, American Society for Testing and Materials, 1973, pp. 108-133 (reprinted with permission). 

Oil spill-treating agents may be applied from boats, hydrofoils, aircraft, or helicopters in the case of large-scale pollution. For minor incidents such as car accidents, the application is done by hand. 

Determine the land area required to conduct the test. If research equipment such as a mist blower or back-pack sprayer is to be used, 1 ha per trial should be sufficient. If commercial equipment such as an airplane or helicopter is to be used, 5 ha per trial for a helicopter and 15 ha per trial for an airplane may be needed. This will vary depending on the type of equipment available the Principal Investigator or contact in the area of the trial should provide this information. Remember, also, that chemical mixing systems at commercial applicator s facilities may require more test product for adequate mixing. 

Sampling Methods From the outset of the high density lake sampling program in 1987, the application of a robust and consistent sampling protocol was considered paramount and this is still the case. Lake sediment and water sampling is performed by 2-person teams primarily from float-equipped Bell 206B helicopters. 

Areas of the North and South Atlantic, and North and South Pacific present continual extreme and hostile ambient conditions that make survival exposed to such conditions a very limited probability with adequate protection measures. In these locations the probability of survival is increased with the provision of a fixed safe refuge rather than the provision of an immediate means of escape. For offshore facilities historical evidence indicates that both helicopter and lifeboat mechanism may be unavailable in some catastrophic incidents. Remote onshore facilities may also experience severe winter conditions that also render this philosophy applicable. 

There are few examples of mass produced MMW radars used for either commercial or military applications. An exception is the US Army s Longbow Apache attack helicopter that is equipped with the Northrop Grumman MMW Longbow radar. The Longbow fire control radar incorporates an integrated radar frequency interferometer for passive location... 

The inability of the engine to produce a useful propulsive force at zero or low flight speeds necessitates the use of an auxiliary power plant to initially accelerate the vehicle to the required take-over speed of the ramjet. Such auxiliary power is also required for controlled landing of the vehicle. As a consequence the ramjet engine is not well-suited for conventional aircraft applications (with the exception of the helicopter) and the principal application of the engine appears to be further restricted to missiles or other similar vehicles of a one-flight expendable nature ... 

Note Bibliography item (2), Method 514.1, Vibration , specifies tests for equipment which may be used in a variety of military applications. The equipment is categorized according to the vehicle in which it will be installed or transported as follows (a) equipment installed in airplanes and helicopters (b) equipment... 

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