3161: Airspeed

2025-11-05T02:06:25Z

2001:569:B923:AF00:1524:4C0F:CED2:C04A: /* Explanation */ Added 427 to the list of comics with a prominent hot-air balloon

{{comic
| number = 3161
| date = October 29, 2025
| title = Airspeed
| image = airspeed_2x.png
| imagesize = 293x338px
| noexpand = true
| titletext = Carefully maneuvering the balloon down a mineshaft in an effort to break the OTHER altitude record
}}

==Explanation==
{{incomplete|This page was created by a HOT AIR ROBOT. Don't remove this notice too soon.}}

In the comic, [[Megan]] and [[Cueball]] are trying to break the record for {{w|airspeed}} in a {{w|hot air balloon}}. Cueball's exclamation "yessss!" suggests that they achieved it when there was a slight variation in conditions that allowed them to briefly reach 2 miles per hour (roughly 3.2 km/h, or 0.9 m/s), which would not seem particularly impressive to most people as it is even slower than typical human {{w|Preferred walking speed|walking speed}}.

Airspeed is the velocity of an aircraft relative to the air it's flying through. This differs from {{w|ground speed}}, which is the velocity relative to the ground below, because it is adjusted for the speed of wind around the aircraft. Most powered-flight airspeed records (from human-powered aircraft to rocket-planes) are made with reference to the attained passage through the air, both because it is traditionally easier to establish from within the craft itself, and in order to disregard either assisting or opposing winds at the flying altitude. Ground speed is usually what passengers care about, since it relates to how soon you'll reach your destination.

Unlike airplanes, helicopters, [[1972: Autogyros|autogyros]] and [[495: Secretary: Part 2|dirigibles]], though, untethered {{w|hot air balloons}} are pushed by the wind itself<sup>[[[285: Wikipedian Protester#top|''circulation needed'']]]</sup> and don't have any other form of horizontal propulsion (changes in the heated air in the balloon allows vertical propulsion due to positive or negative {{w|buoyancy}}, but this is specifically disregarded by the wording used in the comic). This means that their airspeed is normally very close to zero. It may differ occasionally if the wind changes suddenly, in velocity or direction, as it will take a few seconds for the balloon to overcome its inertia. If the wind drops the balloon may coast a bit at the higher speed, but a large balloon will have plenty of drag, so it will not take long to match the new wind speed.

An additional possibility is that it is straddling a significant wind-shear layer that affects the upper parts of the balloon differently from the lower parts, but this does not appear to be the case here, especially as the "level flight" stipulation would seem to disqualify the particularly vertically-turbulent conditions (updrafts and downdrafts) that would accompany this. Away from ground level and the effects of undulating terrain or ground-based structures (and assuming no large powered aircraft have themselves passed nearby, locally disturbing the air), the laminar nature of the air means the airflow tends to more gently transition at the height of a balloon.

Airspeed is useful to aircraft designers and pilots, since it reflects how much power is needed, and the aerodynamic behaviour of the lift and control-surfaces. When you're flying in the same direction as air movement (a "tailwind"), you get more ground speed from the same airspeed, because the wind is boosting your speed; conversely, when you have a headwind, you'll either have lower ground speed with the same engine power, or you'll need more power to get the same ground speed. Prevailing winds in the {{w|middle latitudes}} tend to flow eastwards, which explains why west-to-east flights are often quicker than the corresponding east-to-west flights for such air-commerce as the trans-Atlantic routes between the US and Europe.

A more common record that people try to achieve with balloons is altitude; at this time the current record is 69,850 feet (21,290 m), set in 2005. The title text suggests achieving a ''negative'' altitude record by allowing the balloon to descend down a mineshaft. This could just be in relation to the height of the land in the immediate vicinity of the mineshaft, but could also be with respect to {{w|mean sea level}}, similarly avoiding direct comparison against the ground. With the typical width of a properly inflated balloon being greater than a typical mineshaft, it could be a logistical challenge to make a controlled descent (unless an open pit mine were to be considered a mineshaft — the {{w|Bingham Canyon Mine}} reaches a depth of 1210 m).

Hot air balloons have been referenced previously in the comics [[427: Bad Timing]], [[3153: Hot Water Balloon]] and [[2940: Modes of Transportation]].

==Transcript==
:[A hot air balloon is shown with its six vertical panels alternating in black and white. Megan and Cueball are riding in the basket, with Cueball looking over the side and down while Megan looks at something inside the basket, also looking down.]
:Megan: 0 MPH... 0 MPH... Ooh, 1 MPH with that last gust... 0 MPH... 1 MPH... 1 MPH... '''''2 MPH!!!'''''
:Cueball: ''YESSSS!''
:[Caption below the panel:]
:Breaking the hot air balloon level-flight airspeed record
{{comic discussion}}<noinclude>

[[Category:Comics featuring Megan]]
[[Category:Comics featuring Cueball]]

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3161: Airspeed