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What is 'black box' in Flights ?

After the disappearance of Malaysia Airlines Flight MH370 shortly after midnight on Saturday, investigators considering a range of possible causes - mechanical failure or pilot error - have yet to turn up solid clues. They don't even know where the plane disappeared, which means that for grieving families this misfortune will remain a mystery until the recovery of the plane's 'black box'.
What is this 'black box'? It is actually a flight data recorder (FDR) or accident data recorder (ADR) is an electronic device employed to record any instructions sent to any electronic systems on an aircraft. It is a device used to record specific aircraft performance parameters. Another kind of flight recorder is the cockpit voice recorder (CVR), which records conversation in the cockpit, radio communications between the cockpit crew and others (including conversation with air traffic control personnel), as well as ambient sounds. In this both functions have been combined into a single unit. The term "black box" is popularly referred by the media. The data recorded by the FDR is used for accident investigation, as well as for analyzing air safety issues, material degradation and engine performance.
FDRs are usually located in the rear of the aircraft, typically in the tail. In this position, the entire front of the aircraft is expected to act as a "crush zone" to reduce the shock that reaches the recorder. Also, modern FDRs are typically double wrapped, in strong corrosion-resistant stainless steel or titanium, with high-temperature insulation inside. They are usually bright orange. They are designed to emit an underwater locator beacon for up to 30 days and can operate immersed to a depth of up to 6,000 meters (20,000 ft).

Do you know the chemistry behind airbags ?

Airbags in car as safety equipment inflates within one-twenty-fifth of a second! Have you ever wondered from where does this amount of gas comes in such short interval of time? Where is this gas stored? What makes airbag to inflate? Do the money spend on it really worth? In this article I will discuss the mechanism behind inflation of airbag and the chemistry behind its quick reaction.

The aim of an airbag is to slow the passenger's forward motion as evenly as possible in a fraction of a second. This increases survival chances of the passenger in automobile accidents. In my opinion airbags should be compulsory as car insurances. Slight addition in your car loan can be your invaluable expenditure. There are three parts to an airbag :

1. The bag itself is made of a thin, nylon fabric, which is folded into the steering wheel or dashboard or, more recently, the seat or door.

2. The sensor is the device that tells the bag to inflate. Inflation happens when there is a collision force equal to running into a brick wall at 10 to 15 miles per hour (16 to 24 km per hour). A mechanical switch is flipped when there is a mass shift that closes an electrical contact, telling the sensors that a crash has occurred. The sensors receive information from an accelerometer built into a microchip.

3. The airbag's inflation system reacts sodium azide (NaN3) with potassium nitrate (KNO3) to producenitrogen gas. Hot blasts of the nitrogen inflate the airbag.

Older airbag systems contained a mixture of sodium azide (NaN₃), KNO₃, and SiO₂. A typical driver-side airbag contains approximately 50-80 g of NaN₃, with the larger passenger-side airbag containing about 250 g. Within about 40 milliseconds of impact, all these components react in three separate reactions that produce nitrogen gas. The reaction involved is :

1. 2 NaN₃ → 2 Na + 3 N₂ (g)

2. 10 Na + 2 KNO₃ → K₂O + 5 Na₂O + N₂ (g)

3. K₂O + Na₂O + 2 SiO₂ → K₂O₃Si + Na₂O₃Si (silicate glass)

The inflation system is not unlike a solid rocket booster (see How Rocket Engines Work for details). The airbag system ignites a solid propellant, which burns extremely rapidly to create a large volume of gas to inflate the bag. The bag then literally bursts from its storage site at up to 200 mph (322 kph) -- faster than the blink of an eye! A second later, the gas quickly dissipates through tiny holes in the bag, thusdeflating the bag so you can move.

How Ultra-Ever Dry works ??

Its a hydrophobic coating. According to Ultra-tech, a Florida-based containment provider for chemical clean-up and waste management, its new Ultra-Ever Dry coating is an amazing product. The coating is "super-hydrophobic" and "oleophobic," meaning it repels almost any liquid on a wide range of materials, including – but not limited to – hammers to boots and gloves as you'll see in the following video demonstration.

The two part Ultra-Ever Dry system creates a near invisible barrier of air over surfaces on the nanoscale. These surfaces can range from refined oil, wet concrete, water, mud and other liquids. In industrial application Ultra-Dry could prove ideal for specific applications, like when you drop your hammer in mud, and then step in the mud in your boots, and reach into the mud with your work-gloves.

Water proofing products and barriers are not new but according to the manufacturer, Ultra-Ever Dry has improved adhesion and abrasion resistance compared to previous iterations. The supposed adhesion and abrasive resistance traits then allow for a more diverse range of uses. Other claims include anti-icing, anti-corrosive, anti-contamination and self-cleaning capabilities.

But according to the abrasion resistance notes Ultra-Ever Dry provides "more abrasion resistance than previous superhydrophobic materials." Registering a 110 on the Taber Abrasion Method (ASTM D4060-10) the manufacturer recommends testing of surfaces if abrasion is a concern.

The product can be applied with a spray gun and finishes up to a translucent white sheen. A single coating is reported to last anywhere from 2-8 months in direct sunlight and outdoor conditions before a top-coat re-coating is needed. Indoor and protected outdoor applications put longevity at approximately one year or more. From the underside of a Polar Bear to the backside of a New York taxi driver in August, Ultra-tech professes a working hot/cold range of -30°F to 300°F (-34°C to 149°C).

Can I use it on my SquareBob lunchbox? Maybe. In addition to the "do not breathe this" warning a rather toxic grocery list of chemicals makes up the ingredients, thus making the coating a less than ideal Peanut Butter & Jam option. However, according to Ultra-tech there are no known environmental concerns. The coating is stated to be safe for use in "nonfood" (i.e. not your lunchbox) contact areas of food processing plants and meets FDA and USDA regulations for those types of applications.

The Ultra-Ever Dry coating prices out at $53/quart (0.95 liters) for the bottom coating and $96/quart for the top.