STRUCTURE ASSEMBLY TECHNIQUES : ✈ Drainage and Ventilations Provisions – used to control Moisture within the Aeroplane Structure
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STRUCTURE ASSEMBLY TECHNIQUES : ✈ DRAINAGE Provisions – used to control : • Moisture within the Aeroplane Structure, ✈ DRAINASE – digunakan untuk mengendalikan /alirkan Cairan dan Kelembaban (moisture); sedangkan ✈ VENTILATION Provisions – used to control : Ventilating Air. ✈ VENTILASI – digunakan untuk mengendalikan sirkulasi udara. 2
Airworthiness Requirements : Persyaratan Kelaikudaraan (Kelaikan Udara) - untuk melindungi : Struktur Pesawat dan Penumpang dan Awak Pesawat (crew) 3
Airworthiness Requirements : Persyaratan tentang penyediaan Ventilasi dan Drainase (Ventilation & Drainage provision) – tercantum dalam regulasi CASR paragraf, a.l : PROTECTION OF STRUCTURE § 25.609 (b)- Protection of Structure VENTILATION and HEATING : § 25.831 - Ventilation § 25.1455 - Draining of Fluids Subject to Freezing 4
Ventilations and Drainages § 25.609 (b) – Protection of Structure – requires the aircraft have adequate provisions for Ventilation and Drainage. § 25.831 (b) - Crew and passenger compartment air must be free from harmful or hazardous concentrations of gases or vapors. § 25.1455 - Draining of Fluids Subject to Freezing • If fluids subject to freezing may be drained overboard in flight or during ground operation, • the drains must be designed and located to prevent the formation of hazardous quantities of ice on the airplane as a result of the drainage. 5
Airworthiness Requirements - VENTILATION § 25.831 - Ventilation (a) Under Normal Operating conditions and in the event of any Probable Failure conditions of any system which would adversely affect the ventilating air, the ventilation system must be designed to provide a sufficient amount of uncontaminated air to enable the crewmembers to perform their duties without undue discomfort or fatigue and to provide reasonable passenger comfort. • For normal operating conditions, the ventilation system must be designed to provide each occupant with an airflow containing at least 0.55 pounds of fresh air per minute (0,55 lb/min.) 6
Airworthiness Requirements - VENTILATIONS Persyaratan penyediaan Ventilasi adalah untuk Perlindungan & Keselamatan, y.i : – Proteksi terhadap Struktur (dado/sidewall panel); dan – Proteksi terhadap Pax & Crew: Keselamatan dan kenyamanan (safety & comfort) dari penumpang, dan awak pesawat (menyediakan pertukaran udara segar, bebas dari gas atau uap berbahaya). 7
Persyaratan Ventilasi CASR § 25.831 (e) dan (f) – VENTILATION: • Harus disediakan cara (means) agar Occupants [penumpang, awak pesawat (pilot &copilot), kru selain pilot] di-ruangan berikut, dapat mengatur suhu dan pertukaran udara ke ruangannya, secara terpisah dari suhu & jumlah supply udara ke ruangan dan daerah lain: (1) Ruang awak pesawat (flight crew compartment /cockpit) (2) Crewmember compartments and areas other than the flight crew compartment unless the crewmember compartment or area is ventilated by air interchange with other compartments or areas under all operating conditions. 8
DRAINS & DRAINAGE Regulasi mensyaratkan - pesawat harus dirancang untuk Menyiapkan/dilengkapi dengan : • Drainase (drainage) – untuk mengalirkan cairan, dan kelembaban (moisture) yang terjebak didalam struktur pesawat maupun sistem pesawat, misalnya: akibat kondensasi; pembuangan air dari toilet dan wastafel. • Lokasi drainase – untuk mencegah terjadinya pembentukan lapisan es akibat buangan yang membeku. Persyaratan tsb. merupakan proteksi terhadap struktur. 9
Galley & Lavatory Drains
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Airworthiness Requirements - DRAINAGE § 25.1455 - Draining of Fluids Subject to Freezing. If fluids subject to freezing may be drained overboard in flight or during ground operation, the drains must be designed and located to prevent the formation of hazardous quantities of ice on the airplane as a result of the drainage. 11
DRAINS & DRAINAGE THE FUSELAGE – as with other parts of the structure – will have drain or vent holes (usually underneath / bottom) to allow any water to drain to the atmosphere. This helps to prevent corrosion. • Always ensure they are clear, particularly after a paint respray and after using de-icing fluid. • The Manual will usually have an inverted picture of the aircraft showing the position of all drains/vents. • Many drain holes have valves – that are pressure operated closed to prevent air lose in pressurized hulls (compartments) once pressurization is selected. Differential pressure – discharges the wastewater in flight, and gravity does so on the ground. 12
DRAIN MASTS : DRAIN MASTS - These are : Electrically heated (to prevent them icing up) and Fitted to allow “clean” water (sometimes called grey water to distinguish it from blue water that comes fom toilets) – to drain from galley sinks, toilet sinks, water extractors, etc. • They are fitted in such a way as to allow the water to get cleanly away into the airflow, and • You would not think that they have been the cause of several disasters – but they have ! 13
DRAIN MASTS : If not fitted correctly or have been damaged, discharged water can be sprayed onto the underside of the fuselage. • At altitude this will freeze into a sheet of ice. When removed by the airflow, this sheet of ice can cause (and has caused) serious damage to tailplane/horizontal stabilizer, or other parts of the structure and rear mounted engines. The moral to this story – Make sure that : – The Heaters work, but more importantly – Make sure the Masts do not Leak, and – Are Securely Fitted and Correctly Aligned (Rearward). 14
DRAIN VALVE
DRAINAGE / HOLE 15
FUEL TANK DRAINS
DRAIN VALVE LOCATION – OUTER WING TANK
Detail A 16
FUEL TANK DRAINS
DRAIN VALVE LOCATION – CENTER WING TANK
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DRAIN VALVE Sump Drain Valve (Fig. 22) – are located at the lowest point of each wing fuel tank. • Functions include: – Obtaining fuel sample; – Draining of water and contaminants from fuel tanks; – Draining all the fuel that remains after a defuel procedure; – Checking for fuel in a surge tank before opening access door. 18
DRAIN VALVE
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Fuel Tank Ventilation The fuel ventilation system provides air and fuel vapor flow in or out of the fuel tanks. This prevents too much pressure or vacuum in the fuel tanks. The system relieves pressure when necessary by discharging fuel flow overboard via the fuel ventilation system vents.
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Fuel Tank Ventilation In flight, the ventilation systems lightly pressurizes each wing tank. The fuel ventilation system is fully automatic. In each tank, the system contains a forward and aft vent duct, a vent plenum, float-operated vent / relief valves, nonrelieving float vent valves, an overboard line and a flush vent inlet / outlet (vent / ram air inlet).
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Fuel Tank Ventilation
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Fuel Tank Ventilation • The overboard vent allows fuel to be discarded overboard if the plenum is full. The inlet allows air to enter and exit the tank through the plenum.
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VENTILATION (VENTILASI) Pada Pesawat terbang Penumpang yang Bertekanan (pressurized, passenger transport aircraft) – di daerah lantai fuselage (floor area) / di pinggiran dinding (sidewall area) terdapat lubang-lubang ventilasi untuk menyeimbangkan tekanan di-dalam kabin penumpang dan daerah kargo (cargo bay area). Persyaratan tersebut dicantumkan di CASR 25 §25.831. 24
VENTILATION (VENTILASI) On Pressurized, Pax Transport Aircraft – the floor area/sidewall area will contain pressure equalization holes /vents to allow pressure to equalize between passenger area and cargo bay area. • This requirement is stated in the CASR 25.831.
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VENTILATION (VENTILASI) Persyaratan rancang-bangun untuk Ventilasi tercantum di:
CASR § 25.831 Ventilation. • Kabin penumpang (pax) dan awak pesawat (crew) harus dilengkapi ventilasi agar cukup udara segar (fresh air) > 10. cu.ft/min (cfm) agar dapat melakukan tugasnya tanpa kelelahan (fatigue) dan ke tidak-nyamanan. • Provisi ventilasi tsb. adalah - Untuk memungkinkan pertukaran udara segar, dan pengeluaran /agar bebas dari konsentrasi gas (CO, CO2) & uap yang berbahaya (hazardous) & membahayakan (harmful) dari dalam kabin penumpang dan crew. 26
Ventilation • Tipikal Design Loads untuk Lantai Kabin Penumpang (Pax Cabin Floor) adalah harus mampu menahan, tanpa runtuh, suatu Pengurangan Tekanan yang tiba-tiba (Sudden Depressurization) . A Side-wall Venting System – digunakan sebagai alat /sarana untuk mengurangi efek dari in-flight depressurization akibat pembukaan tiba-tiba dari lubang besar di bawah ruang kargo (cargo compartment ), sesuai dengan persyaratan FAA / DGCA untuk semua pesawat berbadan lebar (wide-body airplanes).
• Venting system yang serupa telah diterapkan di pesawat transport berbadan-lebar L-1011, DC-10, B747 dan juga A300 seri. 27
Ventilation • The invention of vent structure in the cabin area by Dennis E. Murphy is U.S Patent July 5, 1977.
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Fuselage Sidewall Venting System
Dado Panels = Sidewall Vents
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Fuselage Sidewall Venting System Dado Panel (or Pressure Equalization Holes / Vents) – is a sidewall venting in fuselage pax cabin. • Dado panels – are located on the floor area/side wall area between the pax area and cargo bay area, on the pressurized aircraft. • They are spring closed panels in the floor to side wall junction. They open at 0.5 psid in case of rapid decompression to minimize floor collapse and overall structural damage. 30
Fuselage Sidewall Venting System THE USE OF DADO PANELS in Aircraft : To minimize floor collapse and overall structural damage, To allow pressure to equalize between the passenger area and cargo bay area.
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Fuselage Sidewall Venting System BRIEF DESCRIPTION OF THE DRAWINGS
FIGURE 1. – is a cutaway perspective view of a portion of the side wall of an aircraft having the vent structure of the invention installed therein; FIGURE 1. 32
Fuselage Sidewall Venting System BRIEF DESCRIPTION OF THE DRAWINGS FIGURE 2. – is a side cosssectional view of the vent structure of FIG. 1 showing its position when it is called upon to vent large amounts of air from the lower portion of the aircraft fuselage to the upper portion; FIGURE 2.
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Fuselage Sidewall Venting System BRIEF DESCRIPTION OF THE DRAWINGS
FIGURE 3.
FIGURE 3. – is a view similar to FIG. 2 where in a differential pressure of a predetermined value has been established across the floor structure of an aircraft and • The vent structure is beginning to open a large vent area; 34
Fuselage Sidewall Venting System BRIEF DESCRIPTION OF THE DRAWINGS
FIGURE 4.
FIGURE 4. – is a view similar to FIGS. 2 and 3 wherein the vent panel has rotated out of the way to open a large vent area between the upper and lower portions of an aircraft fuselage to relieve pressure in the upper portion thereof. 35
Ventilation Principal Objectives of Ventilation Invention – are to provide : • Means for relieving differential pressures which may be undesirably applied accross a structural wall or floor structure. • Venting means which automatically respond to predetermined differential pressure to open a larger-than-normal venting area for relieving a differential pressure. • Vent means which are economical to manufacture, easy to install, temper proof, and easy to reset after their use. 36
Ventilation Another Objects are to Provide : • Vent means for an aircraft which blend in with the general decor of the aircraft and therefore do not unnecessarily alarm passengers. • A vent structure which, upon application of a predetermined differential pressure, self actuates to open a large vent passageway. • An Emergency Venting Structure – which opens in response to a sensed differential pressure but not in response to externally applied force. 37
AC 43.13-1B REPLACEMENT OF DRAIN HOLES AND SKIN STIFFENERS. Whenever Repairs are made that require replacing a portion that includes drain holes, skin stiffeners, or any other items, the repaired portion must be provided with similar drain holes, skin stiffeners, or items of the same dimensions in the same location. ADDITIONAL DRAIN HOLES may be required – If reinforcement under a skin repair interferes with waterflow to existing drain holes. Make any additional drain holes the same diameter as originals, usually 1/4 inch. 38
AC 43.13-2B 1030. VENTILATION. During the charging process, nickel-cadmium batteries produce hydrogen and oxygen gases. This occurs near the end of the charging cycle when the battery reaches what is called the gassing potential. To avoid a buildup of these gases, and possible accidental ignition, ventilation should be provided to evacuate this gas from the aircraft. There are two types of nickel-cadmium battery cases, one with vent nozzles and one with viewports. • The vent nozzle type utilizes vent hoses to evacuate the gas overboard by use of forced air or by venturi effect. 39
AC 43.13-1B
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AC 43.13-2B • NICKEL-CADMIUM BATTERY INSTALLATIONS. 1025. GENERAL. Nickel-cadmium batteries fulfill a need for a power source that will provide large amounts of current, fast recharge capability, and a high degree of reliability. Nickel-cadmium batteries produce a constant voltage and can operate at lower temperatures. They are generally more expensive to purchase. 41
References / Rujukan : Aircraft Structure Surfce Cleaning Techniques: [1] JSGT : “ A & P Technician, General Textbook ”, JEPPESEN Sanders Maintenance. Ch.8: A/C H/w: Aircraft Rivets, Bolts, Bonding [2] FAA – AC 65-9A: " Airframe & Powerplant Mechanics ,General Handbook “, Consolidated Reprint (includes CHG 1, dated 3/31/99). Ch. 6: A/C H/W: “Aircraft Cleaning” *3+ Niu, Michael C.Y.: “Airframe Structural Design.” [4] EASA: Airbus Aircraft Structures. 42
References / Rujukan : 4. FAA – AC 43.13-1B: “Acceptable Methods, Techniques, And Practices – Aircraft Inspection and Repair ”, Change: 1, Dated: 9/8/98. 5. FAA – AC 43.13-2B: “Acceptable Methods, Techniques, and Practices – Aircraft Alterations”, dated: 3/3/08. 6. CASR /CFR Part 25: “Airworthiness Standards: Transport category airplanes”.
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Definitions, Abbreviations, Translations • Ventilation: ventilasi; lubang angin; peredaran udara; pertukaran udara. • Drainage: pengaliran; drainase; penyaluran air. • Drainage – is a system of drain. • Drain – to draw or flow off of liquid by a gradual process. • Mast (a post, a pillar) – tiang, tonggak.
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Definitions & Abbreviations • Fitting – is a part or terminal used to join one structural member to another. • Butt joint—a joint between two members aligned approximately in the same plane. • Bond —the adhesion of one surface to another, with or without the use of an adhesive as a bonding agent. • Welding — a materials-joining process used in making welds. • Welding rod — a form of welding filler metal, normally packaged in straight lengths. • Welding torch — the device used in gas welding. 45
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