Aircraft Systems and Flight: System Failure

    This week I have chosen to cover the oil system of an aircraft, how a failure in that system would effect an aircraft, and some mitigation efforts to reduce the chances of it happening. To begin, the oil system in an aircraft whether it be a reciprocating engine or a jet engine serves essentially the same function. The oil system lubricates the moving parts, cooling by reducing friction and removing heat from the engine, creates a seal between moving parts, and it carries contaminants out of the engine (PHAK, 2016). I would like to specifically address the failure of the oil pump.

    The oil pump is the heart of the oil system, it delivers pressurized oil to parts of the engine that require it, below is a diagram of an oil system in an aircraft oil system (PHAK, 2016). An oil pump could fail for many reasons to include; manufacture defect, being clogged with contaminants, improper care, and improper oil levels (Loss of Oil Pressure Is An Emergency, 2020). An oil pump failure is first seen by a drop in oil pressure on the oil pressure gauge (Loss of Oil Pressure Is An Emergency, 2020).

    The impacts of an oil pump failure are severe, without the circulation of oil the engine bearings and cylinders lose lubrication, the heat is no longer being dissipated, and contaminates build up. These could lead to the catastrophic failure of the engine in flight if the situation is not taken care of immediately. Even if the engine doesn't fail and you are able to land safely the engine could still require a complete rebuild or even need to be scrapped completely. As you can see, the oil pump is a vital component in the oil system and its failure has severe impacts but there are ways to mitigate it.

    There are several ways to mitigate the failure of the oil pump. As an aircraft mechanic I see this first hand in my day to day job. The first line of the mitigation strategy is to check oil levels and inspect the oil for contaminates prior to each operation of the engine. The second is to change the oil at the recommended intervals to keep the oil system operating properly and to see how easy this can be, view the attached video. The final strategy is to change the oil pump at or before the manufacturer's recommended service life which is usually based on hours of operation. By using these mitigation strategies the chances of an oil pump failure is greatly reduced. 

References:

Loss of Oil Pressure Is An Emergency. (2020). https://www.aviationengines.com.au/loss-of-oil/

Pilot’s Handbook of Aeronautical Knowledge(PHAK). (2016). Federal Aviation Administration.                    https://www.faa.gov/regulations_policies/handbooks_manuals/aviation/phak/