xkcd.WTF!?

Explanation ➲

In this comic, an aircraft is towing a banner. These aircraft do not take off or land with the banner in tow, but instead have a hook and release mechanism to add and drop the banner in flight. The banner could be interpreted as a recruitment ad by an aerial advertising company looking for additional pilots. But the humorous interpretation is that the banner is a distress signal – the pilot of the aircraft doesn't know how to land, and is hoping that someone will see the banner and give assistance. This makes the banner self-referential, because the presence of the banner (which makes landing difficult) is the very reason for displaying the banner. It is paradoxical, because printing and deploying the banner requires planning, and if the pilot had anticipated that they would need assistance to land with a banner, they could have simply chosen not to deploy a banner in the first place.

The aircraft in the illustration is similar to a Piper J-3 Cub, which is popular for tasks such as towed banners for its low operating cost and good performance at low airspeed.

The title text features a caller who dials the "555" phone number from the banner (see Trivia) and starts to explain the correct method for landing (detach the banner over a designated empty location then land the plane regularly), but the call is disconnected halfway through. Presumably the number is that of the pilot's cellphone. The call could have disconnected because the aircraft moved out of range of the cell site the phone was connected to and the phone failed to automatically connect to an adjacent cell; or possibly the cell network detected the call on multiple sites due to the phone's altitude and disconnected it from the network; or the plane crashed and the phone was destroyed on impact. Or perhaps it was always out of service, and this is a prank that someone (like Black Hat) is pulling.