Aerostatic air bearings are excellent for low-speed applications at moderate temperatures. However, they become dynamically unstable at high-speed or high-temperature. In addition, Aerostatic bearings require an auxiliary air supply system, which adds additional weight, cost, and complexity to the system. These disadvantages are, especially with respect to power-related turbomachinery, not outweighed by the benefits; hence aerostatic bearings are rarely used in small-scale turbomachinery. Instead, there application field is mainly in high-speed machine-spindles, centrifuges and optical equipment where complexity and power consumption is less of an issue.

Porous bearings are often used in high-precision applications. They have near error-free motion due to the more uniform pressure distribution compared to conventional aerostatic bearings with orifices. However, they perform poor at high-speed due to the small bearing gap.

Spiral groove (or herringbone) bearings are self-acting gas bearings. This means that they generate their own film-pressure and thus not require additional equipment to operate. Groove bearings are ideal for small-scale applications where a certain self-sustainability and high rotational speed is required. However, groove bearings must have a very small bearing clearance for stable operation. The small clearance cause large friction forces and makes the bearing vulnerable to shaft seizure when thermal shaft expansion occurs. Hence spiral groove bearings are not ideal for high-temperature or power-related applications.

Externally damped bearings are flexible mounting in a damped structure. This increase the total amount of damping such that the system remains dynamical stable at high-speed. The dynamic performance can be further improved by changing the center bore to a non-circular geometry. Examples of this are the multi-lobe or wave-shaped bearings. However, a couple of limitations prevent the use of these bearings in high-temperature applications. First, these bearings have a rigid surface which does not flex in case of thermal shaft expansion. Second, the required external damping structure is generally quite sensitive to temperature.

Foil bearings have a compliant bearing surface to allow thermal shaft expansion. A typical foil bearing consist of a smooth metal top foil supported by a folded bump foil. The bump foil act as a spring, making the top foil compliant. This allows the top-foil to move radically outwards whenever the shaft expanse. Foil bearings have been successfully implemented in many applications, such as air-cycle-machines, gas turbines, and turbo compressors. The inner diameter of a typical foil bearing is approximately 20mm in size and upwards. Unfortunately, attempts to downscale the bump foil concept for small-scale applications have failed in the past, mainly because of scaling-laws and manufacturing restrains.

The last generation of tilting pad bearings are virtually free of the disadvantages that foil bearings have. In contradiction to foil bearings, tilting pad bearings are more stable and can be manufactured for smaller journal diameters. In addition, the beneficial bearing compliance can be achieved by mounting one or more pads on a flexible hinge structure. Shaft growth can then be accommodated by the radial compliance of these hinge structures. The stable nature of tilting pad bearings allows for larger bearing gaps and thus lower power losses. Consequently, the new generation of tilting pad bearings are the ideal solution for small-scale and power related turbomachinery.