Monday, June 29, 2020

Maintaining Systems - An Investigation into An Air Crash - Free Essay Example

maintaining systems Introduction In this study I have decided to look at the Air Crash Investigation, Airbus A380 Titanic In The Sky (Qantas 32). This incident happened vary recently in 2014. The plane that I am looking at is considered to be one of the biggest commercial aircrafts in the world carrying up to 525 passengers at the time In this report I will be going through the issues that this monumental aeroplane went through. I will be investigating what caused the damage to the aircraft and also how it could have been prevented. How often do faults happen? On an aeroplane so big, and in trust of so many lives there is very small room for faults to happen. Saying this there are always little problems that can occur but are can never be fatal. During one of the flights landings it experience problems with the hydraulic brake lines causing the plane to brake slower than usual. Luckily this was not a problem as the runway was long enough. After this inci dent all of the planes hydraulic lines were checked and replaced if deemed to be faulty. Another incident would have been the steering when taking off. This was caused by one of the sensors on the aircraft to be too sensitive, not giving the pilot enough steering capacity. Although this was a problem on take-off, when it came to landing the fault was fixed during flight by re programming the sensor. These two faults that were recorded were quickly dealt with and therefor had no impact on the safety and integrity of the aeroplane. There was a problem that cause a lot of media attention due to the severity of the incident. This was a malfunction in one of the 4 Rolls Royce engines, each can deliver 72,000 pounds of thrust, during a flight from London to Sydney Australia. What went wrong? To start off, during the long flight a problem occurred with the 2nd engine on the left wing. After a detailed investigation it was confirmed that the problem was down to an oil pipe. The pipe broke in two causing the oil to lubricate the turbine, this then caused them to move faster. This created a lot of friction resulting in an oil fire. How the investigators know this The evidence was back tracked using certain methods. First of all they collected all the debry to find the initial cause of the malfunction. Immediately the indecent was all over the news and through this the company was able to locate all the engine parts that were scatterd around. Through analysing the parts they found a dark soot on the side walls of the engine. Later tests revealed that this was an oil based fire. Now they had to find out what the fire caused. As the fire progressed it got too hot for any preventions to work with what soon followed. The heat of this fire was over 1000 degrees Celsius, far more than what the product was intended to deal with. This is due to certain tolerances that land rover follow. (they should now increase the tolerances their materials can have) They decide what the worst case scenario that could happen and built the design around that. It was never thought that the flames would get so hot so this caused a main part of the engine to fail. Through measuring a plate of very dense nickel, they found that it had expanded through the forces acting on it. This was due to the heat created allowing the turbine to move faster than sound itself. Due to the forces acting on the plate, it expanded until breaking point. Where it then exploded at an infinite force cutting through anything in its way. These fragments went through main operating lines throughout the wing causing even more problems. While this was all happening the pilots on board the aircraft were flooded with error after error. There is a system in place which allows the pilots to see and act on the faults. This is called the Ecam, which has feedback from over 250,000 sensors on board the aircraft. During normal training pilots only go through about 5 faults at a time, b ut on this incident the pilots had to go through 58 faults. These faults were due to fragments cutting though hydraulic and electrical connecters. This meant that they had little to no control over the left wing putting so many lives in danger. Now the investigators went back to the initial cause to see how the oil pipe broke. This was due to a very simple manufacturing fault when the pipe was made. It turns out that one side of the pipe was only 0.35mm thick (about the thickness of a couple pieces of paper)and it should have been 2mm thick. Due to vibration the oil pipe broke causing major damage to the aircraft. A picture of this is shown on the right. Once the Plane was landed they found that engine 1 was still running. They turned it off by the switch but nothing happened. All the electric to the engine had be seethed, therefor having no control of it. The passengers were not aloud of the plane as the engine was still running. The fire department had to flood the engine s with fire retardant foam to stop the engine. This took just under 3 hours. The consequences of this fault could have been fatal if it werenà ¢Ã¢â€š ¬Ã¢â€ž ¢t for the flight team. After this incident all aeroplanes with this engine were put on hold to ensure the problem didnà ¢Ã¢â€š ¬Ã¢â€ž ¢t happen again. This was a serious problem as there were 20 planes that were now out of service. A program was devised to check the thickness of the faulty oil pipes. All 80 engines were surveyed after this incident and the company found the there were 34 other engines with this very fault. They were taken out of use. Was it maintained? Research suggests that this part of the engine was not checked as it is a fault thought to be impossible. As they found this was not the case. If they had done a better check they would have found this fault before the planes were allowed to fly. Now there are serious implications on weather Rolls Royce are responsible enough to check the engine com ponents in high detail before they are sent to the aircraft manufacturer. Maintenance schedule? Prior to this event the aircrafts were to be checked every 2 years, this seems like a time scale that is too far apart due to the amount of lives it is trusted to protect. The company now checks the aircrafts on how many miles they fly so that they have a very high chance of preventing any risks. These maintenance tasks can take months to complete costing the company millions of pound but as they see it. At least the passengers will be safe from harm. Who should do repairs? Only people who are qualified to do repairs are allowed to. This is mainly the supplier of the parts as it is souly their responsibility. To reduce safety Risks Companyà ¢Ã¢â€š ¬Ã¢â€ž ¢s will only insure a product if they are the ones that maintain them. Otherwise if a problem does occurs and it isnà ¢Ã¢â€š ¬Ã¢â€ž ¢t down to them. It could still affect the company and lead to fines Conclusion The ov erall fault that cause this was the pipe being manufactured incorrectly, causeing the engine to explode and create a series of events that the pilots were lucky to avoid. In future more care is to be tacken during production and better systems have now been put in place to check the quality of the product. If the product is not adequate to do the job then it will not be used Sources https://www.flightglobal.com/page/A380-In-Service-Report/Airbus-A380-In-Service-Technical-issues/ https://www.youtube.com/watch?v=-xnTTjEkdD0 16/10/2014