How much impact does Marine One have on the White House lawn when it lands?

Gregg Gray:

Marine One creates very little damage to the White House lawn, though it does stir up a significant amount of pollen from the trees. If the lawn hasn't been cleaned recently, small debris might be blown across the area, affecting both the people and the surroundings. This can be especially noticeable if the lawn has just been aerated.

The lawn has been specifically designed to endure twice the downward thrust generated by the helicopter (a costly feat). Anything lightweight on the lawn must be securely fastened with screws or latches to prevent movement.

In the image below, you can see the three large circular landing pads, each measuring 8 feet across. These dimensions are determined by the height of the doorway where they are stored. The pads help distribute the weight of the helicopter over a much broader area than if it simply landed on the grass.

The grass does get slightly bent but recovers within an hour or so in the sunshine. The landing pads aren’t left in place for long—only about 30 minutes at most.

Those attending the president's arrival in dresses or skirts must hold onto their clothing to prevent it from being blown over their heads. Similarly, any unbuttoned topcoats are often sent flying into the crowd. As the saying goes, 'Hold onto your hats.'

The Marines who operate the helicopter have perfected the landing technique. They execute it with precision and, in gymnastics terms, they 'stick the landing.' The most challenging part is storing the three large landing pads, as they take up considerable space.

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