The Spacing Guild Heighliner in Dune is one of the more iconic starships in science fiction. Helighliners serve as means of transportation, fulcrums for events and convenient plot devices throughout the books of the series. In the first novel, they were described as being of such gargantuan size that Duke Paul Atreides says:
‘A Heighliner is truly big. Its hold will tuck all of our frigates and transports into a little corner-we’ll be just one small part of the ship’s manifest.’
Heighliners were not described beyond this at all in the original six novels and were instead just a simple plot device to move Character A to Planet B.
In David Lynch’s 1984 film adaptation, Heighliner were giant ornate cylinders bisected by a deep trench along the major axis. The written impressions of massive and literally awesome size were depicted by the tiny hatch through which all the Atreides starships fit.
The Dune Encyclopaedia (1984)
In The Dune Encyclopaedia (download link), fan-authored by Willis E. McNelly in 1984, is quasi-canonical. While Frank Herbert accepted much of what was presented in the Encyclopaedia (or at least didn’t contest it despite his endorsement), his son Brian Herbert has discredited the work. As a fan of the original series who (in a twist of irony) considers Brian Herbert’s books to be outside of the senior Herbert’s canon, I am happy to accept the Encyclopaedia. The Dune Encyclopaedia described Heighliners as:
a simple, featureless globe…a network of girders and cables…covered only by the light aluminum skin
McNelly gave no specific size, which fits with the spirit of the novels.
SyFy’s Dune (2000)
In SyFy’s 2000 adaptation of Dune Heighliners were depicted as a framework of interlocked counterrotating sections left open to the vacuum space. Its interior volume was crosshatched with girders, spaceships and anchored modules which you can see it in action here.
I consider a solid cylindrical Heighliner to be more canonical: Frank Herbert integrated visual elements from the film related to the Guild, back into the final two novels. His son continued to use continued to use these same elements. So if it is more canonical, it is through endurance. Brian Herbert also provided the length of a Heighliner in Dune: House Corrino: Twenty kilometres.
With that in hand, I went and screencapped Dune, brought it into Photoshop to take measurements. The Heighliner on my screen was 309.92 pixels long and 86.77 pixels wide. Let us apply…math!
(86.77 / 309.92) * 100 = 27.998
Rounded up, a Heighliner’s width is 28% that of its length. This isn’t great, but it is good enough. A further bit of math delivers the Heighliner’s approximate width:
20000 * 0.28 = 5600
For comparison: you can fit two Babylon 5’s facing each other end-to-end inside of a single Heighliner:
Fan-wank aside, I took further measurements to let me draw it with the correct proportions:
20000:5600 = 25:7