System and Sub system Analysis
System and Sub system Analysis
PROGRAM: System Safety SYSTEM/SUBSYSTEM: Hydraulic System
|1.||Over-pressurizing||Greater and faster wearing out.||Results to permanent failure||2D||Control with the specified pressure levels at its designs specification.||3E||§25.144|
|2.||Loss of pressure||Failure of the hydraulic pump or fluids outflow||Leads to destruction of the hydraulic device.||1D||Regular and proper repair is mandatory. Moreover, a back-up system should be installed.||2E||§25.1435|
|3.||Fire||Hydraulic fluid getting heated to high temperatures||Occurrence of explosions leading to damage of property and injuring personnel.||1A||Installation of fire protection measures such as automatic sprinklers and extinguishing systems. Training of personnel on how to handle the flammable fluid.||3C||§25.851
|4.||Contamination||Presence of materials in a closed hydraulic system hindering efficiency in operations.||Speeds up the rate of wear and tear of the pump||3D||Inserting of filters to prevent particles from accessing the hydraulic system. Cleaning of the welding burrs breaking off in the system.||3E||§25.1121|
|5.||Over-heating||System exceeding its maximum operating temperature causing damage to the seals.||Leads to loss of hydraulic system.
Leakage due to the damaged seals.
|1B||Training personnel on how to control the system within the design specifications.||1D||§29.1353|
Hazard condition Item.
Hazard Condition Fire: In order for the hydraulic system to function, it has to utilize the pressurized fluid. All the regularly used hydraulic fluids can be combustible. The flash points vary from 300 degrees to 600 degrees. In the case that these fluids release under pressure in fine mist, they can be ignited easily in combination with an ignition source therefore burning rapidly and emitting a lot of heat which can result to a fire outbreak. Therefore, burning and flare-up of the flammable and combustible liquid can result to loss of lives and damaging property.
Hazard Condition Item 2 Loss of pressure: System pressure loss can take place in two different ways such as loss of fluid or hydraulic pump failure. Leakage in the system can result to hydraulic system failure. Flow of fluid can be disrupted in a hydraulic circuit as a result of internal or external leakage. Bust hose is usually obvious and easy to trace. It is more difficult to isolate internal leakage in the pump, valves or actuators. In the case that there is loss of pressure, all the control systems of the aircraft operated by the hydraulic system will be unresponsive resulting to a crash.
Risk Assessment 2 for Fire: 1A– There is a likelihood of the loss of lives if the flammable and combustible hydraulic fluid is not contained. The severity of the fire hazard is unacceptable for a system that contains large amounts of flammable fluid. When the fluid discharged in fine mist is exposed to the environment, it can easily ignite and burn rapidly resulting to emission of large amounts of heat. The consequential explosion may lead to loss of lives. This happens frequently due to the many ways in which the fluid maybe exposed to the environment. They are often quiet and invisible such as leakage. The severity level is therefore catastrophic and the probability of occurrence is frequent has been determined as 1A.
Risk assessment 2 loss of pressure: 1D– pressure can leak from the hydraulic circuit through external or internal outflow. Internal outflow is rather hard to locate while it is easy to trace external leakage. The loss of hydraulic pressure is very critical in the aircraft. The loss of pressure in the system is comparable to an aircraft losing its limb since all flight controls all activated by the hydraulic system resulting to loss of control by the pilot (Jones,2012) . This doesn’t happen frequently but once it happens it is undesirable. Therefore, the severity level is remote determined as 1D.
Recommendation to reduce the risk.
Fire recommendations: It is vital to have protection against fire outbreaks. There has been the manufacture of hydraulic fluids with fire resistant properties for aviation use. The liquids are phosphate esters, contrasting with the mineral oil based hydraulic fluids, ignition at room temperature is rather difficult. This can reduce the possibility of ignition. Sprinklers and other fire extinguishing systems should be installed to subdue the fire if a fire outbreak would occur from the hydraulic system. A controlled risk assessment code of 3C can be assigned if the above proposals are implemented. However, the fire occurrences will be occasional and minimal due to the available measures.
Recommendations for Loss of Pressure:
It is important to tackle the issue linked to the leakages in order to decrease the risks of loss of hydraulic pressure. To achieve that, it will be important to carry out regular maintenance and inspections to identify early warning for such failure. The regular maintenance and inspection should be assessed in both the internal and external parts of the system. The effort of prevention should be proactive. Early signals such as slow response, operation and performance should be detected early enough and actions taken accordingly to avert any danger (Bahr, 2018). A controlled risk assessment code of 2E can be assigned since such an occurrence is improbable. The consequences can be critical if it happens.
Bahr, N. J. (2018). System safety engineering and risk assessment: a practical approach. CRC press.
Jones, R. B. (2012). Risk-based management. Routledge.