Gregg Gray:

Marine One does almost no damage to the White House lawn. It does blow lots of pollen out of the trees, however. If it has been a while since the lawn was vacuumed, little bits of debris are blown from the lawn onto the awaiting people and surrounding area. It is really harsh when the lawn has been recently aerated.

Everything on the lawn has been selected to withstand twice the downward thrust of the helicopter (which isn't cheap). Anything below a certain weight has to be fastened down with appropriate screws or latches.

In the photo below, you can see the three big circular pads it lands on. They are 8 feet across (the dimensions are set by the height of the doorway where they are stored), and they spread the load of the chopper out over a much wider area than just landing on the grass would do.

Official White House Photo by Chuck Kennedy, Public Domain, Wikimedia Commons

The grass gets bent a little bit, but it springs back within an hour or so in sunshine. The landing pads aren't out there very long—30 minutes tops.

What does happen is that those individuals who have worn a dress or skirt to see the president’s arrival have to hold their garments down to keep them from being blown over their heads ... Any topcoats that aren't buttoned up will often fly all over bystanders as well. As the old saying goes, “Hold onto your hats.”

The Marines [who pilot the helicopter] have it down to a science ... They do it very well and very smoothly and, in gymnastics terms, they “stick the landing.” The hardest part of it all is storing those three landing pads, as they take up a lot of room.

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