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Here you may see a few articles that have appeared in some of the magazines.

1. Super Jumbo-A380

2. Black Boxes

3. Dove Farming in Thailand

4. Edible/ Inedible

5. Large Numbers/ Small Numbers.

6. Translucent Creatures (Science Fiction)

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800-SEATER SUPERJUMBOS ARE COMING……A380 (Only a Part of the Article Appears Here)

By Bimal K. Srivastava,

A huge double-decker, twin-aisle Superjumbo airliner A380 manufactured by Airbus Company of Europe, and based on Fly-By-Wire technology is likely to be ready for test flights by March 2005 and for commercial flights by 2006. This 550 to 600-seater aircraft, which, was earlier known as A3XX, was launched in December 2000 and entered production in January 2002, and has already made its appearance in Jan, 2005. The aircraft is not only equipped with a unique design and most efficient performance, but will also be the largest civil aircraft ever produced so far. Advantages of the A380 include lower fuel burn per seat and lower operating costs per seat. Airbus A380 will have a non-stop range of 14100 Kms. The extended range version may fly even up to 16200 Kms. Thus airlines will be in a position to operate non-stop flights between Delhi/ New York, Mumbai/Melbourne or Tokyo/New York. Presently two basic models are currently being marketed, the A380-800 passenger model (formerly called A3XX-100) seating up to 555 in three classes and the A380-800F freighter version (formerly A3XX-100F). Passenger version can be used as a 600-seater aircraft in a single seat configuration. Additional extended range, passenger/cargo, and stretched models are also under consideration. Its other advanced models (e.g. A380-900 or higher) may accommodate even up to 800 passengers in a single seat configuration. The estimated cost of A380 could be around US $250 million (or about Rs. 1200 Crores). A380 aircraft would become the main competitor for the present day Jumbo Jet (Boeing-747) manufactured by the Boeing Company of USA. As the market trends indicate, A380 may even out beat B747 in terms of seating capacity, space and developed technology.

WEIGHT & DIMENSIONS This huge aircraft has a length of 73 Mts. (239.5 ft), Wing span 80 Mts. (262 ft), and height as 24.1 Mts. (79 ft). In other words A380 would look even taller than a 7-storeyed building. The weight of the empty aircraft is 274,875 Kgs. and with full load of fuel, cargo and passengers it weighs as much as 540,000 Kgs. It can carry up to 261 tons of fuel and 85 tons of passengers and cargo. For the sake of comparison, the dimensions of the present day largest aircraft, Boeing 747-400 vis-à-vis A380 are given below; Dimensions Jumbo Jet (B747-400) A380-800 (Largest Civil aircraft (Latest as on date) Introduction) Length 70.7 metres 73.0

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the airlines. MANUFACURING PROCESS AT AIRBUS Airbus is a consortium formed by EADS (European Aeronautic Defence and Space Company) and BAE Systems. The EADS was formed by the merger of Aerospatiale-Matra of France, Daimler-Chrysler Aerospace of Germany and CASA of Spain (former members of Airbus). British Aerospace (BAe) was first formed as a nationalized corporation in April 1977 by the merger of the British Aircraft Corporation, Hawker Siddeley Aviation, Hawker Siddeley Dynamics and Scottish Aviation. Airbus manufactures a series of Airbus aircraft such as A300, A310, A320, A330, A340, A318, A319, A321 etc. Out of the above, A300, A310 & A320 are flying for Indian Airlines and Air India also. It is interesting to note that manufacturing units of various parts of all kinds of Airbus aircraft (e.g. A300, A310, A320, A330, A340, etc.) are located in different countries in Europe. For example the wings and the Landing Gears (wheels) are manufactured in UK, Main cabin and the fuselage in Germany, Cockpit, and engine supports (Pylon, Nacelle etc.) in France and Horizontal Tail plane (Parts of the tail assembly) in Spain. And fully equipped aircraft sections are then air-lifted by an odd-looking giant sized aircraft known as “Airbus Super Transporter A300-600ST” (Which is also manufactured by Airbus ) with the most voluminous cargo hold in the world and brought to the final assembly lines in Toulouse, France. It is amazing that the extra large-sized parts of massive Airbus aircraft are engulfed inside the deep belly of the Super Transporter and carried from one country to other. However, due to the unprecedented size of A380 aircraft, airlifting is not possible and therefore, complete aircraft sections are delivered by surface transportation (sea and road) to Toulouse for structural assembly, final equipping (including engine installation) and production test flights. The aircraft then flies to Hamburg for cabin furnishing, systems installation, customization and painting. Etc. It is unbelievable and wonderful to see that these Airbus parts made at different places are joined perfectly with the parts manufactured hundreds of kilometers away, exhibiting the extreme limit of the precision with which the manufacturing process is controlled. IMPROVED DESIGNS Several innovative manufacturing techniques have been selected for the A380 program. Some are so advantageous they will go into mass-production for other aircraft programs of Airbus. It may be seen from the under mentioned paras; Weight Reduction Measures This aircraft is adopting most modern technology to reduce the weight despite aircrafts’ incredible bulk. It is estimated that out of 275 tonnes of empty weight of the aircraft, the structure will consist of 140 tonnes of aluminium alloy, 35 tonnes of carbon fibre re-inforced plastic (CFRP), 15 tonnes of titanium, and 13 tonnes of high strength steel. Another important aspect of the design is the extensive use of CFRP (carbon fiber reinforced plastic), the latest generation of carbon composites. CFRP, besides being lighter than traditional materials, is also on the cutting edge of operational reliability, maintainability, and easy repair. Thus an estimated 40 percent of the aircraft's structure and components will be manufactured from the CFRP and advanced metallic materials.

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Hydraulic and Electric Systems for Flight Controls For the first time ever in civil aviation, the A380's hydraulic system will have increased Hydraulic pressure for handling its flight controls (Higher than the conventional 3000 psi, i.e. pounds per square inch on conventional aircraft). This will help in designing of smaller sized components, connections, and piping to reduce the aircraft weight by roughly a ton and will also improve maintainability. (Military aircraft already use these high-pressure systems.) In addition to increased hydraulic pressure, a dual architecture was installed for the flight control system, with both hydraulic and electrical energy sources. Never before on civil or military aircraft have the flight controls been governed by both hydraulic and electrical circuits. The A380 will also get a completely re-designed double spool air generation system that has more efficient thermo-dynamic cycles; provides more flexibility between different air generation requirements on the ground and at cruise; takes up less space; and provides more redundancy and damage-resistance. HUGE ENGINES YET ENVIRONMENTAL FRIENDLY A380 will be equipped with four engines; “Trent 900” manufactured by M/s. Rolls-Royce, or GP7200 Engines by “Engine Alliance” a joint venture between General Electrical and Pratt & Whitney of USA, with mighty power of 70,000 pounds per engine. Due to its new generation engines and advanced wing and undercarriage design and technology, the A380 will not only comply with current noise limits but will also meet projected international and local noise thresholds. Consequently, the A380 will be quieter than present day wide-bodied jets. Noise per passenger (an increasingly relevant measure for airlines and airports) generated by an A380 will be half that of a Boeing 747, meaning the A380 will fully comply with the new strategy to cut yearly noise levels at airports. It is also designed to taxi within only two engines and uses only two thrust reversers and also employs a low noise auxiliary power unit, so as to reduce ground noise during aircraft manoeuvres on ground. The A380 is also expected to emit lesser amount of greenhouse gases in the high atmosphere (although regulations do not yet exist for these emissions) by burning up to 15 percent less fuel per passenger than a Boeing 747. AIRPORT REQUIREMENTS A380 would need 2,900 metres of runway length for take off under standard conditions and it can be easily manoeuvred on ground on existing taxyways and runways, wherever Jumbo Jets (B-747s) are operating. Refuelling of A380 can be carried out in 40 minutes. The turnaround time at the airport terminal, including passenger disembarking, cleaning, restocking and embarking the passengers for the next flight is a minimum of 90 minutes. With most large airports already congested and air traffic forecasted to double within the next 15 years, the introduction of a larger-capacity jet such as the A380 comes as a solution to the increased demand without further increasing congestion. However, as most of the existing airports were designed to accommodate the Boeing 747, currently the largest civil passenger aircraft, the development of a larger capacity aircraft like A380 would bring with it some of new challenges to the aviation industry. As the A380 will be longer, wider, taller and heavier than B-747, and will be able to carry up to 50 per cent more passengers; airport organizations are taking up various challenges to cope up with the increased congestion in departure lounges and security areas, delay in collecting passenger luggage and longer boarding line-ups. M/s. Airbus are claiming to have designed this aircraft in such a way so that this would be able to operate within the designed confines of the entire world’s major airports. Due to that reason, Perhaps, normally no modified aerobridges would be needed for embarking/ disembarking of passengers. Similarly, for operation of the Airbus A380 no modification of runways or taxiways would be needed. Only minor modification will be needed if the loading and embarkation/disembarkation of passengers is to be done on the lower deck. However, certain airports are gearing up themselves to accommodate to provide dedicated facilities such as direct upper deck boarding by modifying their aerobridges.

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This can be resolved judiciously by arranging the time of operations in such a way that it does not clash with peak-hour arrivals and departures. Ideally, speaking Mumbai and Delhi airports are best suited for handing A-380 aircrafts (Of course with some additional work to the done at the airports). This may be followed by Kolkata and Chennai later on. USER AIRLINES A380 is being purchased by a large number of airlines. It has already received firm orders from Singapore Airlines (launch customer with an order for ten aircraft), Lufthansa (15), Emirates (43), Air France (10), Qantas (12), Malaysia Airlines (six), Virgin Atlantic (six) International Lease Finance (ten) and Qatar Airways (two), Federal Express (10), Korean Airlines (5), Etihad Airways (4) and Thai Airways International (6), bringing the total firm orders to 139 from 13 customers. In addition they are getting orders from China Airlines, North West Airlines and many more. Thus Airbus has now almost received 149 firm orders for it’s a-380 aircraft till mid-January 2005. It is expected that with an initial production rate of four a month, Airbus may be having a backlog of orders until at least 2007. The biggest boost had come from Dubai based Emirates Airlines that had placed a huge purchase order to Airbus for supply of 43 aircraft at a mind boggling price of 12.5 billion US $. This was a morale booster for Airbus, being the largest order for its super baby A380. This new aircraft may revolutionize the flying experience, and then people would be saying that they have now entered a new aviation era.

BLACK BOXES (Only A Part of the Article Appears Here)

…… BY BIMAL K. SRIVASTAVA

An Air India B-747 (Jumbo Jet) aircraft while on a flight from Mumbai to Dubai fell into the Arabian sea, two minutes after its take-off from Mumbai. The pilot had not passed any emergency message on Radio and everything appeared to be normal before the accident. So much so , even the pilot had conveyed new years greetings (It was 1st January night) on radio to the Radar Controller on ground a few seconds before crash.

However the accident took place and the Jumbo hit the sea with such an impact that the total aircraft got embedded into sea bottom (The depth of water was hardly 10-15 meters at that place), resulting into a watery burial and sudden death for all the 213 occupants of the ill fated aircraft. Unfortunately, since it was a winter night, there were hardly any witnesses to the mishap.

Finally Indian Navy and the local fishermen were able to search the wreckage (and could retrieve the black boxes) after three days. On re-play of the black boxes it was established that the "Attitude Direction Indicator (ADI)" instrument that provides the information about the attitude of the aircraft (its bank, pitch, direction etc) had failed resulting into disaster.

From the above example it is evident that the black boxes play a very important role in aircraft accident investigation. That is why whenever an aircraft accident occurs, the first and foremost job (of course other than search and rescue) is that to locate the black boxes.

WHAT ARE BLACK BOXES.

The black boxes are special instruments (in the shape of rectangular boxes) which continuously record the flight details and the cockpit conversation during flight. Black boxes are not one but TWO separate instruments known as "Cockpit Voice Recorder (CVR)" and "Flight Data Recorder (FDR)" respectively.

CVR and FDR, though entirely separate instruments, yet externally they almost look alike (in shape, size and colour). Moreover, though these instruments are called Black Boxes, they are normally bright red or orange in colour. The name `BLACK BOX' has been given to them, perhaps due to the fact that the information contained inside these units is not known unless and until the unit is played on a special recorder.

These units are contained in strong rectangular metallic boxes which are capable of withstanding high degree of shock and extensive heat arising as a result of aircraft crash (Manufacturers term them as crash-proof). They can also resist heavy rain, fire or any other odd of this nature. The normal size of a black box is 13 X 20 X 30 cms and its weight is about 10 KGs. Thus they are comparable to a brief case in shape and size. Normally these boxes are installed towards the rear portion of the aircraft, as it is believed that this area of the aircraft is less prone to damage during an accident.

Inside the tough boxes, the soft and delicate tape is sheltered that actually performs the important job of recording flight details and cockpit conversation. This tape is either a magnetic tape or a thin metallic foil. It is surprising that even after such heavy impact, fire, extensive heat, or continuous contact with water, the metallic boxes provide a perfect shielding to the vulnerable tape; and normally the recordings do not suffer damage.

The black boxes start functioning as soon as the aircraft engines are started and they stop when all the engines are shut down.

Black boxes are fitted with a typical sound transmitters operated by a special battery, which is known as acoustic underwater locator beacon assembly. This unit is a battery-powered device, which radiates pulsed acoustic signals into the surrounding water upon activation of its water sensitive switch. The beacon consists of a self-contained battery in electronic module and a transducer. The water sensitive switch gets activated whenever it comes in contact with water (either sweet water or saline water).

This may happen in the event of the aircraft falling into sea, lake or river, when the transmitter starts operating and a peculiar "Beep Beep" sound is produced on a regular and continuous basis that can be heard from a distance of 3 kms (of course by means of special receivers). Once `on' the battery continues working for about 30 days. The idea is that that aircraft wreckage even submerged in water can be searched by the help of this sound.

It may be mentioned that the CVR and FDR of Air India Jumbo jet "Kanishka" that had fallen into Irish sea on 23rd June 85, could be located and retrieved from a deep sea-bed of more than 2000 meters by combined efforts of the naval fleets of Canada, Britain, Ireland and France through the help of these sound transmitters, which otherwise would have been impossible to get.

COCKPIT VOICE RECORDER (CVR)

Cockpit Voice Recorder (CVR) enables in presenting the recorded voice conversation of crewmembers of the aircraft. Its primary purpose is to provide valuable evidence in determining the cause of an aircraft accident, however, it can be used for other purposes also such as Incident Investigation, checking the performance of Crew Members, computing the speed of Engines and Propellers, routine monitoring of aircraft data etc. In India it is mandatory for all turbine-powered aeroplanes of 5700 KGs and above to have CVR fitted.

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The four tracks of the CVR (termed as Channel 1, 2, 3, or 4) record either transmitted or received signals that originate typically at various crewmember stations or that of Area Microphones. Normally Channel 1 record communications received and transmitted on Flight Engineers head set. However in case of the aircraft which do not have Flight Engineer's position such as Boeing 737, A-320 etc., Channel 1 records Cabin Crew communications (including

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For example, in 1974 one Lufthansa B747 aircraft crashed in the Nairobi when its CVR was read out, it was found that the pilot had forgotten to extend the leading edge flaps during take-off check list, and therefore the aircraft could not derive adequate lift causing it to crash. The cause of this accident could be established only because of the CVR Tape transcript.

Similarly when the CVR of the Air India B747 aircraft "Emperor Ashoka' that had crashed near Mumbai on 1-1-78 was played back, the following cockpit conversation was heard:

- "My Instruments are toppled"...(Captain)

- "Mine is also toppled"...(Co-pilot)

- "No but, go by that Captain"...(Flight Engineer)

Due to that it could be later established that the aircraft had crashed due to failure of pilots "Altitude Director Indicator (ADI)" that gives the information about the altitude of the aircraft during Flight

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For example during the investigation of an accident pertaining to an aircraft which was delayed and was departing very late during night, the CVR transcript revealed that the pilot was telling to his co-pilot

"Yaar Mujhe Bahut Neend Aaa rahi hai"

(I am feeling very sleepy)

This clearly showed the mental state of crewmember who was undertaking the flight at such an odd hours.

Similarly sometimes the CVR showed that the crewmembers were in a very light and jovial mood occasionally to the extent of not paying much attention towards the flight. In one of the accident, it was found that the commander who happened to be a close relative of the trainee pilot, also going for his supernumery flight, was so much engrossed in explaining to him the flight procedures, that he almost forgot about many vital points to be observed during the crucial phase of landing. This aircraft ultimately crashed on a hill at a stage when the crewmembers were least aware of the obstruction ahead. On the other hand, many times, the flight crewmembers are found very sincere and they follow all the procedures and checklist thoroughly.

FLIGHT DATA RECORDER (FDR)

The other black boxes viz. FDR records flight details such as aircraft speed, altitude, direction, gravity, and rate of climb/ descent and time. It normally contains a metallic tape on which the information gets permanently engraved by a special probe (like a gramophone needle). Its tape can run for 25 hours of flight and then a new tape is installed.

FDR provides valuable information about the aircraft and its flight. For example the time of accident can be exactly pinpointed. Similarly it can also be known whether speed, altitude of the aircraft were normal or any abnormality was noticed. If, so what could be the cause of that and so on.

In modern aircraft like Jumbo jet (B-747), Airbus, A320 etc. a new type of computerised flight data recorder called Digital Flight Data

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(BIMAL K. SRIVASTAVA)