But since the 1960s, satellites and aircraft with powerful radar devices have discovered more and more lakes buried kilometres beneath the thick ice sheet.
BBC: NEWS | Science/Nature | Secret rivers found in Antarctic
In October 2010, al-Awlaki was involved with a new attempt by al Qaeda in the Arabian Peninsula to blow up U.S.-bound aircraft by inserting explosive devices in printer cartridges destined for the United States.
The United States Post Office did not require the Letter Logger to do this, however, in part because mail often travels in aircraft, and transmitting devices must be switched off during take-off and landing.
On propeller driven aircraft, balloon-like devices attached to the wings and tail are inflated and deflated with air from the engines, breaking up any ice accumulation.
Recall that GM once bought Hughes Aircraft and EDS as growth devices (around 1980, ) and opened the greenfield Saturn division to learn how to compete with offshore auto makers head-on.
Some 7, 000 unmanned aerial vehicles, from small hand-launched devices to big robotic aircraft fitted with laser-guided bombs, are now deployed in Iraq and Afghanistan.
Honeywell executives, who haven't previously discussed the project publicly, say the system uses onboard computers and navigation devices to automatically control aircraft movements on the ground.
With the aid of visual and aural warnings, these safety enhancements use software, cockpit displays and related devices already installed on aircraft to alert pilots about potential mistakes.
With the advent of new and evolving electronic technology, and because the airlines have not conducted the testing necessary to approve the use of new devices, the FAA is taking a fresh look at the use of personal electronic devices, other than cellphones, on aircraft.
FORBES: FAA Taking "Fresh Look" At Use of Personal Electronics on Planes
For many years, passengers have been told that some electronic devices, including cell phones, can interfere with aircraft navigation and communication signals.
He said the fact that the two devices had been carried on a series of five aircraft, three of them passenger flights, raised "serious questions about the security of our airspace".
The mechanism of EMI causing failures seems plausible, logical, and reasonable until you consider the energies involved in portable devices, the lack of on the ground EMI incidences in aircraft, and the lack of EMI incidences in other vehicles.
Since late 2003, Baron claims, Sirius XM has sold "tens of thousands" of subscriptions to Baron's service. (Sirius declines to confirm that.) The devices can be found in newer Cessna, Cirrus and Piper aircraft and can be installed in boats and various mobile GPS gadgets for hunters and fishermen.
Using the Gogo exclusive network and services, passengers with laptops and other Wi-Fi enabled devices can get online on more than 1, 500 commercial aircraft including all domestic AirTran Airways and Virgin America flights, all domestic mainline Delta Air Lines flights and select Air Canada, Alaska Airlines, American Airlines, Frontier Airlines, United Airlines, and US Airways flights.
ENGADGET: Gogo spreads its in-flight WiFi wings further with SES satellite deal
These devices are compatible with extremely sophisticated manufacturing techniques for production of modern aircraft particularly military aircraft.
The devices often serve as a backup in case the electrical systems and radio in the aircraft are inoperable.
In September, the NTSB recommended the FAA require large planes and other aircraft on which the wingtips are not easily visible from the cockpit to have cameras or other devices to monitor the wings.
In September the National Transportation Safety Board recommended the Federal Aviation Administration require large planes and other aircraft on which the wingtips are not easily visible from the cockpit to have cameras or other devices to monitor the wings.
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