Broken seats in commercial aircraft are more than just inconveniences, and while a defective seat by itself cannot cause a major safety issue inside a plane, it is often an indication of a bigger, ongoing problem.

The seats used by every passenger on commercial aircraft are quite sturdy things: They are designed to resist fairly high G-forces and the weight of an adult for hours at a time. They are easy to clean and modular, so that if something fails it can be repaired or replaced between flights. However, seats are today being, literally, overwhelmed by big fannies.

Indeed, lack of maintenance can cause problems in seats too, and it is easy to associate that with the quality of service in an airline, but overweight passengers make repairing and maintaining things more difficult and costly. If you consider that just a brand-new, aircraft-grade seat belt could cost about seventy dollars, imagine what costs to actually repair a whole seat.

The average weight of an adult human in an aircraft has been calculated years ago at 77 kg - this is an ICAO standard. Aircraft are normally designed with tolerances of 30% or so, meaning that you can have people of up to 100 kg or so sit safely for a variety of reasons that go from the resistance of the seat materials to weight and balance distribution in the aircraft.

But here is where problems begin: Aircraft have not been designed in this fashion so that obese people would fit better inside, but due to safety concerns as well as flight mechanics: Indeed, when a plane flies it is subjected to increased "Gs" at times. This means that during those phases of flight, the plane "weights" more or less than it really weights. For example, if something that flies suffers 2G, even for an instant, its weight doubles and the structure suffers two times the stresses than normal. Thus, if you consider that today, people in some countries like the US are averaging about 92kg, it is easy to see that things are reaching the limit in terms of safety.

New aircraft are indeed being designed taking into account the new parameters but there are many vehicles - not just old aircraft - that still offer only the older standards. It would be nonsensical from a financial point of view to force every manufacturer and operator to change things just because people don't eat well. Moreover: Since the average weight of adults actually tends to increase and is expected that in a few years it will go beyond 92 kg. Such changes would not result in any long-term positive solution. Making sturdier seats usually means leaving less space inside the fuselage of ain aircraft or the body of a car, bus, etc. which means higher transportation costs per passenger because the vehicle will be forced to carry less people or cargo.

In the case of small aircraft it usually means replacing the whole fuselage, something prohibitively expensive unless the plane is yours and you are desperate to fly without paying much attention to weight loss. Indeed: you can get wider fuselages for little planes like a Piper Cub, but that means losing a lot in the power-to-weight ratio as well as aerodynamics, so the trade-off may not be acceptable for everyone.

Anything that goes beyond the tolerances must be deemed as unsafe locally - i.e. the seat will likely break - and globally -i.e. such overweight will alter the weight and balance of the plane and put it outside the safety envelope. Since you cannot modify aircraft easily or quickly, the only sensible solution to the problem is unfortunately to leave overweight people in the ground.

This is why sometimes pilots choose to leave obese passengers behind; it is not a matter of discrimination, but physics.

Source: Pablo Edronkin, Andinia.com

Additional, suggested searches:

Bibliography.

Related Products.

More about this topic at Andinia.com.

Debates about this in our forum.

Related games and entertainment.

Department of Homeland Security (DHS) Secretary Janet Napolitano las Wednesday traveled to Mexico City at the invitation of her Mexican colleague, Interior Secretary Fernando Francisco Gómez-Mont, to meet with officials from North, Central and South American and Caribbean and the International Civil Aviation Organization to discuss ways to bolster global aviation security measures and standards.

"The international dimensions of the Dec. 25 attempted terrorist attack and the international threats posed by violent extremists require an international response to bolster global aviation security measures," said Secretary Napolitano. "... meetings with representatives from countries across the Western Hemisphere underscore our ongoing commitment to working together to enhance and strengthen the ways we protect the global aviation network from terrorists."

Following last week's meetings, Secretary Napolitano and the participating officials issued a joint declaration on a way forward to strengthen the international civil aviation system through enhanced information collection and sharing, cooperation on technological development, and modernized aviation security standards—viewable at http://www.dhs.gov/xabout/international/gc_1266421175567.shtm.

While the U.S. Transportation Security Administration (TSA) does not conduct screening at foreign airports, Secretary Napolitano is committed to strengthening coordination with international partners to implement stronger and more effective measures to protect the integrity of the global aviation network.

In Mexico City, Secretary Napolitano stressed the need for collaborative international action to prevent terrorists from boarding commercial aircraft during meetings with ministers and representatives from Argentina, Brazil, Canada, Chile, the Dominican Republic, Mexico and Panama—the second in a series of major international meetings intended to build consensus on strengthening global aviation security.

Secretary Napolitano also emphasized the Obama administration's commitment to strengthening information sharing with international partners about terrorists and other dangerous individuals who pose a threat to the global aviation system. In 2009, DHS, the Department of Justice, and the Department of State worked together to forge agreements to prevent and combat crime with Greece, Italy, Spain and Portugal by allowing for the exchange of biometric and biographic data to bolster counterterrorism and law enforcement efforts while ensuring privacy protections.

In Mexico City, Secretary Napolitano met with Mexican President Felipe Calderon to discuss both aviation and border security collaboration. She also joined Secretary Gómez-Mont to sign a letter of intent to coordinate closely on a number of mutual aviation security initiatives—including deploying enhanced airport screening technologies, strengthening passenger information sharing, and ensuring passengers have proper travel documents.

In January, Secretary Napolitano met with her European counterparts in Toledo, Spain, resulting in a similar joint declaration between the United States and the European Union on a way forward to strengthen the international civil aviation system.

Secretary Napolitano also traveled to Geneva to meet with members of the International Air Transport Association—which represents approximately 230 airlines and more than 90 percent of the world's air traffic—as part of the Department's efforts to work with the airline industry to ensure all flights to the United States meet both international and TSA security standards now and in the future. She also met with officials from the International Civil Aviation Organization in Geneva on these issues.

Source: U.S. DHS

Additional, suggested searches:

Bibliography.

Related Products.

More about this topic at Andinia.com.

Debates about this in our forum.

Related games and entertainment.

NATO Defence Ministers began their informal talks in Istanbul with a focus on resources and defence transformation at a working dinner on 4 February.

Ministers agreed on a package of measures to ensure that the Alliance's books are balanced. They decided that as a basic principle NATO must sufficiently fund Alliance operations and missions and make essential strategic investments. Ministers also committed to inject additional resources into the budget this year, as well as to modernise how NATO does its budgeting and looks for savings where it can.

"Making savings includes doing more together, and that will deepen the solidarity between Allies", stressed the NATO Secretary General Anders Fogh Rasmussen.

He pointed out that the package of measures agreed "will ensure that our soldiers get the support they need in the field and that we can make the other strategic investments we still need. Solidarity in NATO means on the front line: but it also includes the bottom line. We have seen that solidarity here in Istanbul"

In that regard, NATO Defence Ministers decided to focus on three priorities: countering improvised explosive devices, improving medical care for our soldiers by making sure they get the best support possible and fielding more mission-capable helicopters.

During the meeting, NATO's Supreme Commander for Transformation General Stéphane Abrial presented his proposals for how we could improve NATO allies techniques, training and technologies, to better protect the soldiers in the field.

Allied ministers agreed on the need to improve medical care for the Alliance soldiers, by making sure the capabilities they need are in the field.

They also pledged in favour of fielding more mission-capable helicopters, by tying together countries that have the helicopters, with those that have the money for moderisation and deployment, and the training for personnel.

Source: NATO News

Additional, suggested searches:

Bibliography.

Related Products.

More about this topic at Andinia.com.

Debates about this in our forum.

Related games and entertainment.