MY DAILY WEEK SEVENTEEN - TIME TO CRY A LITTLE

TIME TO CRY A LITTLE:

My contribution:

ATA 32

Landing gears have two main functions:

• Supporting the weight of the stationary aircraft on the ground

• Absorbing the loads during touchdown, the landing run and taxiing

They are divided into two main categories, fixed for small aircraft or fully retractable for larger aircraft.

It is divided into several components: brakes, wheels, shock absorber, hydraulic system…

Each brake consists of a brake housing assembly (hydraulic supply) and a carbon composite hot section.

Shock absorber is to absorb and dissipate the tremendous shock loads of landing

Hydraulic oil to absorb and dissipate the shock loads, for landing gear retraction and expansion

And the wheels, I don't know what to say about the wheels…

Tell me everything you know about Module 11 - the nightmare module (for some - Mr. Buades loves it!)

Time is running out, the tunnel is getting shorter, the light is getting brighter but we have one GIGANTIC hurdle to overcome. Module 11 is there, guarding the entry to our internship, trying to stop young students from finding their personal Nirvana.

But, they not be defeated, the know the secret passwords and this is what this blog is about.

This longest module ins the couuse becasue includes different ATAS of the manual and every ATA has a different function.

32 is a favoured ATA: we have two systems. Autobrake and Antiskid. The first one is to brake automatically and the anti skid is similar to the ABS in cars. In the wheel we have a sensor for the rpm and one computer compares the rpm of the wheel and the velocity of the aircraft and if they do not have the same rpm, we have one valve and it opens and closes the hydraulic pressure so that the wheel doesn’t slide.

The first ATA we saw was water and waste and it is ATA 38. Mostly, as students and future technicians, we would not want to dirty our hands and souls with this ATA. We don’t mind dirtying our hands with oil but waste is another kettle of fish. However, waste must be dealt with. Most of the aircraft now have two tanks where all the waste goes to. These tanks have to be drained when they are full. There is a sensor which informs on this. They have to be drained manually and sometimes, the hose disconnects from the receptacle and human excrement hits the fan.

Structures: Mind-blowingly rivetting for some but disheartening for others. They are designed to be completely safe with the design philosophy named safe life. This means that that component will have to be replaced after some flying hours (specified by manufacturers) independent of its condition. Obviously, if it is broken, it has to be replaced. Structures are very reliable because they have to pass some stringent tests for their certification.

ATA 35: oxygen (the breath of life). What would we do without it? Oxygen gives meaning to our lives and as such it is a vital part of an aircraft. This is because in the case of depressurization, we are able to breathe for about 12 minutes to reach the minimum safety altitude for the passengers to breathe normally. One thing that is important about oxygen is that we have to be very careful when we are going to do the maintenance of the bottles or when we are going to refill it because oxygen is very flammable and volatile. So no smoking here (Mr Garcias and Mr Medina). The bottle has to be clean and there mustn’t be any grease on the cap of the bottle and where the oxygen comes out.

ATA 24: Electricity. Where sparks fly! Nowadays, all the aircraft need electricity. In the aircraft we can find two types of electricity: AC and DC. Normally, the AC electricity is about 115 Volts with 400 Hertzs and three phases and the DC electricity is 28 volts. Then in every engine, in the gearbox (normally) we find a generator. This generator provides AC current. Then we have TRU that transforms the AC current to DC current.

Young Jordà: ATA 27: Flight controls (switches and buttons and interesting things). The control surface, spoilers, etc….

During the flight, we need different surfaces. For example, flaps. We have some lift when we land and we need velocity for landing.

ATA 33: Lights. First of all, we divided this subject in three chunks. The external lights were the first one, the second one was the lights inside the plane and the third one was the emergency lights. If we talk about the external lights, we could talk about the navigation lights. There are three of them. One is green and it can be found on the right hand side on the wing tip. The other one is red and can be found on the other wing on the left hand side. The third light is white and it can be found on the tail. So, we could now talk about the anti collision lights which are very important because, for example, if we know that we are going to start the engines, then we will have to switch on these lights to warn the team of workers outside the plane that the engines will start to run. Another light that we would talk about are the landing lights. As its name indicates, these are used for landing. We will switch on these lights when we are cleared for take off and when we start rolling and preparing for take off it will be on and we will also have to switch on these lights during the landing operation. Another external light is the taxi light also, as its name indicates, we will have to switch on this light during taxiing.

Internal lights: These can be cabin lights and the cockpit lights and the cargo lights.

Finally we have the emergency lights and if we have to evacuate the aircraft, these will be used.

ATA 30: The first one Pau studied. Ice and rain protection. This explains how the plane is protected from the weather. In this ATA we see ice and rain as two main weather components. We learn about the different types of ice and how they work against the different functions of the plane and which tools we use to prevent this ice. To prevent the ice we work with the air from compressors to prevent the formation of ice leading edge of the plane. On the windscreen of the cockpit, we use a special liquid which helps us to remove the ice and prevent its accumulation. On the ground, some specialist applies a special solution so that ice doesn’t get on the wings.

ATA 29: Hydraulic systems. The aircraft has three reservoirs and one of them is a standby reservoir. They are pressurized with 50 psi. There are four hydraulic pumps. Two are electric and two are connected to the motor. The pumps which are connected to the motor are more powerful than the electric ones. We use hydraulics to move the flight controls and normally we need about 3000 psis.

ATA 36: Pneumatic systems. This can be divided into two main areas which are the low pressure system, typically medium to high volume. Low pressure systems that are used for aircraft for the engine starting, wing anti-ice, engine anti-ice, cabin and air conditioning, pressurization of the cabin and other. Then there is the high pressure systems. This tends to be lower volume but higher pressure. It is used to operate flaps, landing gear etc.