Scale model aircraft: the 1/72 guide, and the scales around it

Scale is a ratio, nothing more. At 1/72 the model is one seventy-second of the real thing in every dimension, so a wingspan of 11.23 m becomes 15.6 cm. Everything else on this page follows from that one division.

Where the number 72 comes from

It comes from imperial drawing practice, not from anything to do with aircraft. Draughtsmen worked in fractions of an inch to the foot. One sixth of an inch to the foot gives twelve inches divided by one sixth, which is 72. The ratio was popularised in Britain in the 1930s by Skybirds, a range of wooden solid model aircraft built to that scale, and it carried over to injection-moulded plastic kits after the war, which is why it is still the broadest scale in the hobby.

The other common aircraft scales come from the same habit: a quarter of an inch to the foot is 1/48, three eighths is 1/32, half an inch is 1/24, and 1/144 is simply half of 1/72.

The scale ladder

Spans below use a Spitfire Mk IX at 11.23 m and a B-17G at 31.62 m, so the columns are directly comparable.

Why 1/72 wins for a collection, and where it loses

It wins on three counts. Almost every aircraft that has ever been kitted exists at 1/72, including the obscure ones. A four-engine bomber is still 44 cm, which a normal shelf can take. And a collection of thirty models at 1/72 fits where a collection of thirty at 1/48 does not.

It loses on two. Cockpit and undercarriage detail is genuinely hard to see, so the extra work you put in disappears. And new tooling money increasingly goes to 1/48 for fighters, so the newest and most accurate kits of popular subjects are often the larger ones. For a first build, part size matters more than range, which is why the first kit guide recommends 1/48 and this page does not contradict it.

Mixing scales on one shelf

Two models at different scales standing side by side lie to the eye: the viewer reads the size difference as a difference between the real aircraft. A 1/48 fighter next to a 1/72 bomber makes the bomber look like a trainer.

Three ways to handle it, in order of preference: one scale per shelf; separate cases by scale; or, if models must share a shelf, put the larger scale lower and further forward, so perspective does some of the work. Grouping by scale is the first of the four schemes in the display guide.

Doing the arithmetic yourself

Span in metres divided by the scale gives the model span in metres. In imperial, multiply the span in feet by twelve and divide by the scale to get inches. That is the whole method, and it settles arguments about whether something will fit.

The last line explains why airliners live at 1/144 and below. A 747 at 1/72 is nearly a metre across and needs a room, not a shelf.

Ship scales, for comparison

Ships use a different ladder. Plastic warship kits cluster at 1/700, usually as waterline models so that a whole fleet fits on a shelf, and at 1/350, which is the mainstream detail scale. 1/200 exists for large single subjects. A 270 m aircraft carrier works out at 38.6 cm at 1/700, 77.1 cm at 1/350, and 1.35 m at 1/200.

Wooden ship kits ignore all of that and are sold at whatever scale suits the hull and the box, commonly between 1:50 and 1:100. That is one reason wooden and plastic ship models rarely share a display, and it is covered in the wooden kit guide.

Scale

The ratio between model and original, written 1/72 or 1:72. Both notations mean the same thing.

Box scale

An odd scale chosen so the model filled a standard box, common before the 1970s. Why some older kits are 1/76 or 1/50.

Waterline

A ship model built only down to the waterline. Standard practice at 1/700 and the reason fleets fit on shelves.

Constant scale collection

A collection built entirely at one scale, so relative sizes are true. The single decision that makes a display look considered.