Each passenger got direct aisle access, something Singapore, like Delta, found travelers really do value.

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But yin yang doesn't allow direct aisle access for window-seat and middle-seat passengers.

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But this unique configuration gives each window seat its own private alley of access to the aisle, something I have never seen and really liked.

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British Airways, which has a patent on the yin yang pattern, doesn't think direct aisle access is a major issue for most travelers, said Simon Talling-Smith, BA's executive vice president for the Americas.

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For Delta, which eliminated international first class years ago, the new herringbone layout yields 48 business-class seats on the Boeing 747, 17 fewer in the same amount of space as the older design, which didn't have horizontal flat beds and direct aisle access for every passenger.

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In the increasingly split world of air travel, where only elite fliers have access to better (even just aisle or window) seats, shorter lines, and free baggage allowances, it is more important than ever to accrue these miles.

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Poland refused, blocking access to the bus's narrow aisle as at least 21 children escaped out of the back emergency door, according to police.

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Their differences notwithstanding, both sides of the aisle seem to agree that expanding access to affordable health care is of dire importance.

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Smaller planes mean only one aisle, fewer aisle seats, less room to walk around in and less access to lavatories, which can make a difference on long-haul flights.

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