How Do Aircraft Air And Oil Separators Work?

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To keep an aircraft functional and healthy, one must always be sure to routinely carry out cleaning, maintenance, and repair. With the combustion of fuel-and-air mixtures within the engine, air/oil mist may be produced and dumped overboard through the crankcase breather system based on the makeup of the engine assembly. This will often cause a collection of grunge and substances on the belly of the aircraft and other areas, making it important to control such flows. To do this, devices known as air/oil separators are used, those of which are able to scavenge oil vapors so that they can be rerouted back to the crankcase for potential reuse as well.

Air/oil separators are fairly straightforward in their operations, acting as condensers with a robust filter capable of converting oil mist into liquid oil and air. A typical air/oil separator will come in the form of a metallic canister with an inlet and outlet, the former being attached to the crankcase breather tube. As oil mist passes through internal baffles, the oil will collect and condense, separating from the air. The oil will flow into a drain, eventually making its way back into the crankcase to be reused for lubrication. Meanwhile, another exit will be provided for the separated air, ensuring that it is vented from the system and into the surrounding atmosphere. As these separators are generally mounted to the firewall or rear engine baffle, there may be a need for drilling and trapping the crankcase so that a dedicated entrance to the engine can be established. However, some may not use an extra return line, allowing for a more simple installation process.

Air/oil separators first came about when many aircraft utilized wet-vacuum pumps. The vacuum pumps were very useful for standard operations, but since autopilots featured servos which were vacuum bellows that pulled cables to move controls, the pumps would work very hard and required internal lubrication so that they could draw enough air to make up for leaks. With this method of operation, vacuum pumps sucked in oil before blowing it out of the exhaust alongside the air that drives gyros and servos. With oil being expelled overboard, the lubrication system is considered a “total loss” type. As such, the air/oil separator was created to recover this lubricating oil so that it could be returned to the engine.

If your aircraft does not have a wet pump vacuum, you should not need an air/oil separator. This is because many modern aircraft now have dry vacuum pumps that do not need lubrication. Nevertheless, some separators may be used for the simple means of reducing oil consumption. If your aircraft has a dry vacuum pump and still has major losses of oil, then a separator may not be the best option as the issue will be something separate. As such, when it comes time to begin shopping for parts, make sure that you have determined whether or not you need an air/oil separator.

Here at Aerospace Orbit, we can help you secure competitive pricing and rapid lead times on aircraft engine parts like crankcase kit, oil cooler, and air/oil separator products. Take the time to explore our offerings as you see fit, and our team is always ready to support you with customized quotes for your comparisons on items of interest. If you happen to be facing a time constraint, rest easy knowing that we are able to expedite the shipping process for domestic and international orders using our expansive supply chain network. Get in contact with a team member of ours today and see why countless customers steadily rely on our services for all their projects.

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1. christopher wilson
2. Posted on September 21, 2022
aviation

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