They were then commanded to reduce their height by a factor of two (to 23km) for another three months, allowing them to obtain data at an even better resolution.

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It's difficult to determine height accurately, it was maybe three or four hundred feet, quite a bit lower than helicopters would normally fly at.

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This meant that for the drop-test we were able to let the Panasonic free-fall from a height of three feet, while the GammaTech was dropped from a somewhat less realistic (in terms of likely real-world falls) one foot.

ENGADGET: Durable faceoff and torture test: Panasonic's Toughbook 30 vs. GammaTech's Durabook D15RP