Methods for using tethered unmanned aerial vehicle having at least one task sensor

A method comprising:

• tethering, with a tethering cord, a first unmanned aerial vehicle (UAV) to a ceiling, a vertical wall or a second UAV, the tethering cord having an extendible and retractable length;
• performing at least one task, by the first UAV, to an object during flight of the first UAV in a movement mode configured for maneuvering near a surface of the object;
• sensing, by a task sensor, at least one parameter of the surface, wherein the task sensor comprises at least one of:
• a contact surface or a probe element;
• resiliently adjusting an adjustable sensor arm attachable to the first UAV and supporting the task sensor, to facilitate the at least one task performed to the surface of the object by the first UAV during flight of the first UAV, the adjustable sensor arm being resilient to impact forces caused by direct contact of the task sensor or the adjustable sensor arm with the surface to bend, spring or swivel relative to a contour of the surface;
• and
• during the tethering, extending or retracting the tethering cord by a motor, while the first UAV performs the at least one task.