Why Are Newly Built Airplanes Green?

In a world where the majority of aircraft are now painted white, planes with green fuselages are a relatively rare sight. Various exceptions exist in the form of certain military aircraft and those flown by Russian carrier S7 Airlines, but, otherwise, it is a color seldom seen. However, you may have noticed from factory photos that most airliners start off with a green coat of paint, but why exactly is this the case?

A practical choice rather than an aesthetic one

The first thing to know is that the green paint job that newly built aircraft receive in their first days is not the consequence of a stylistic decision. After all, if the color was such a hit at that stage, why not retain it for the rest of the plane’s career? Instead, the reason for this look stems from practical considerations.

Specifically, according to Aircraft Technic, the paint used is a green zinc chromate or zinc phosphate primer, which manufacturers apply to newly built aircraft to prevent corrosion. This is a key preventative measure that keeps a new plane’s aluminum surfaces intact during the early days before its first full paint job.

As it happens, this practice actually came from a different manufacturing sector before being adopted by the aviation industry. Indeed, the use of a protective zinc chromate primer was reportedly first popularized by car manufacturer Ford as early as the 1920s, before spreading to commercial and military aircraft.

Other considerations

There are also several other factors at play when it comes to the use of green zinc-based primers on newly built aircraft. For instance, AeroPeep notes that it also serves as a base coat for the eventual top coat of paint that is applied to the plane before being delivered to its customer. As such a coat would be needed anyway, using the primer for this purpose helps to kill two birds with one stone.

You might also be wondering why the shades of green used on new aircraft sometimes differ. Indeed, the Boeing 737 MAX pictured below is painted in a dark but shiny shade, whereas the Airbus A380 seen above has a lighter matt finish. According to Aircraft Technic, this is down to manufacturers using different primers.

The increasing use of composites in modern commercial aircraft production, which feature a combination of materials whose characteristics enhance each other’s qualities, has also changed things a little. Namely, Aircraft technic adds that areas of new aircraft that feature composite materials are painted with blue primers.

Yellow used to be the go-to primer color

Looking a little further back in time, we can see that newly built aircraft were previously painted with yellow primers for anti-corrosion purposes. However, according to Toolify, the zinc chromate was toxic and even carcinogenic, so a type of carbon black known as lamp black was added to the mix to reduce its toxicity. The presence of this additive resulted in the color change from yellow to green.

Source: simpleflying.com