Boeing 747-400 aircraft still use floppy disks to update their software.

The impressive Boeing 747-400s that continue to fly through the skies – with the pandemic, certainly less so – have a curious secret: when their software needs updating, that update is done via floppy disk.

The experts from Pen Test Partners were able to take a look at the internal systems of one of these aircraft and discovered to their surprise that 3.5-inch floppy disk drives are used to update the navigation databases that are key to each flight.

Insert diskette…

It seems strange, but it makes sense if we consider that these planes were introduced in 1988 even though their life cycle is now ending. The CDs had barely made an appearance and the USB sticks, for example, would not start selling until the year 2000. Watch the 7:50 minute video.

Floppy disks dominated the computer world, so using them to load updates into the onboard systems of these planes was a coherent decision.

A group of experts from Pen Test Partners had the opportunity to access one of the Boeing 747s temporarily withdrawn from the British Airways fleet because of the COVID-19 pandemic, and after inspecting the avionics they noticed a unique detail.

They discovered a 3.5-inch floppy disk drive in the cockpit that is still used to load key information from navigation databases. These databases are updated every 28 days, and an engineer performs the update using these disks every month.

The data is actually not so striking: the Boeing 737s continue to use these drives as well, and although the databases are getting bigger and some airlines have installed other alternatives, in these cases the process is still done by loading the information that lately needs 8 disks (we assume that 1.44 MB disks are used, then these updates take about 11.5 MB in total) to update airports, routes, runways and other data.

The video that these researchers published was part of their talk at the famous convention of security experts, DEF CON, which due to the pandemic was held virtually. There were many interesting questions in the question session, but one dominated all the others: was it possible to gain access to flight systems by hacking into the plane’s entertainment systems, for example?

These experts explained that this seems impossible: “We have been deliberately looking at this and have not found any two-way communication so far between the systems of the passenger domain such as the IFE (In-Flight Entertainment) and the aircraft control domain.

That doesn’t mean you can’t try to access the IFE system. A researcher from a Scottish university did just that on a nine-hour transatlantic flight, but actually only managed to knock out his own screen with a buffer overflow.

By Javier Pastor – Xataka