𝐀𝐏𝐔 𝐅𝐢𝐫𝐞 𝐃𝐞𝐭𝐞𝐜𝐭𝐢𝐨𝐧 & 𝐄𝐱𝐭𝐢𝐧𝐠𝐮𝐢𝐬𝐡𝐢𝐧𝐠 𝐒𝐲𝐬𝐭𝐞𝐦

APU Fire Detection & Extinguishing System

🛩️The APU fire protection system is similar in design to engine fire protection systems, but there are some differences. The APU is often operated with no personnel in the flight deck and; the APU fire protection system can operate in an unattended mode on the ground with the engines not running.

🛩️If there is an APU fire in the unattended mode, the fire extinguisher discharges automatically. The APU operates in the attended mode when at least one engine is running. If there is an APU fire in this mode, the crew discharges the bottle manually. Fire switches are located on the cargo fire/ engine control panel and the service and APU shutdown panel located outside the airplane on the nose landing gear.

🛩️If there is an APU fire, the APU fire detection system gives fire warnings and automatically stops the APU. The APU fire warning light comes on to identify the correct fire switch to use to extinguish the fire. The fire switch solenoid releases the switch so that it can be pulled up. If the APU is running, it stops when the fire switch is pulled. The fire switch isolates the APU from the airplane systems.

🛩️If the fire warnings do not go away with the switch out, put the switch to the left or right DISCH position. Hold the switch against the discharge stop for one second. This fires the bottle squib and releases the fire extinguishing agent into the APU compartment. Verify that the APU bottle discharge light comes on.

➡️Subscribe us for more aircraft knowledge and aircraft fact⬅️
➡️Do Share with your Friends⬅️

Comments

𝐓𝐲𝐩𝐞𝐬 𝐨𝐟 𝐂𝐨𝐦𝐛𝐮𝐬𝐭𝐢𝐨𝐧 𝐂𝐡𝐚𝐦𝐛𝐞𝐫𝐬

🛩️A combustor is a component or area of a gas turbine, ramjet, or scramjet engine where combustion takes place. It is also known as a burner, combustion chamber or flame holder. In a gas turbine engine, combustion chamber is fed high pressure air by the compression system. 🛩️The combustor then heats this air at constant pressure. After heating, air passes from the combustor through the nozzle guide vanes to the turbine. In the case of a ramjet or scramjet engines, the air is directly fed to the nozzle. 𝐀𝐧𝐧𝐮𝐥𝐚𝐫 𝐓𝐲𝐩𝐞 ✈️The most commonly used type of combustor is the fully annular combustor. Annular combustors do away with the separate combustion zones and simply have a continuous liner and casing in a ring. There are many advantages to annular combustors, including more uniform combustion, shorter size, lighter, and less surface area. Annular combustors tend to have very uniform exit temperatures. They also have the lowest pressure drop of the three...

𝗠𝗼𝗻𝗼𝗰𝗼𝗾𝘂𝗲 𝘃𝘀 𝗦𝗲𝗺𝗶-𝗺𝗼𝗻𝗼𝗰𝗼𝗾𝘂𝗲 𝗦𝘁𝗿𝘂𝗰𝘁𝘂𝗿𝗲

🛫A monocoque structure uses its outer shell to support stresses and loads applied to it, whereas a semi-monocoque structure has an internal "skeleton" of supports and braces to keep its shape rigid and strong. 🛫The vast majority of pressurized aircraft are semimonocoque to help distribute stresses equally along the fuselage during flight. 🛫However, some helicopters use monocoque structure to maximize internal space in the flight compartment. 🛫Monocoque fuselage has its skin holding the skeleton structure together while the semi-monocoque has both the skin and the skeleton holding together. 🛫Semi-monocoque also has "stringers" running horizontally down the plane to help hold the frame together. 🛫The monocoque fuselage also cannot be used for airframes after a certain size (small aircraft with single engine), but the semi-monocoque has been used from single piston engines to commercial airliners. 🛫A monocoque design would also have ...

𝐖𝐞𝐭-𝐒𝐮𝐦𝐩 𝐎𝐢𝐥 𝐒𝐲𝐬𝐭𝐞𝐦

Wet Sump Oil System ✳️The engine oil system performs several important functions: 🛩️Lubrication of the engine’s moving parts . 🛩️Cooling of the engine by reducing friction . 🛩️Removing heat from the cylinders . 🛩️Carrying away contaminants . 🛩️Providing a seal between the cylinder walls and pistons. ➡️Subscribe us for more aircraft knowledge and aircraft fact⬅️ ➡️Do Share with your Friends⬅️

The Aviation Science

Search This Blog