| CPC B64C 29/0091 (2013.01) | 11 Claims |

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1. A ducted fan device comprising:
fan devices each comprising:
a fan that rotates about a first axis and generates an airflow; and
a cylindrical smaller duct surrounding the fan about the first axis and extending in a first axis direction; and
a cylindrical larger duct extending in a second axis direction parallel to the first axis, wherein
each of the fan devices is disposed inside the larger duct when viewed in the second axis direction,
at least a part of the smaller duct is disposed outside the larger duct and upstream of the larger duct in a flow direction of the airflow when viewed in a direction orthogonal to the second axis direction, and
in the flow direction, a downstream end face of the smaller duct of each of the fan devices is disposed upstream with respect to an upstream end face of the larger duct.
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