New research shows that athletes who compete in the world’s fasted non-motorized sport — speed skydiving — may reach 600 kilometers an hour, or more than 372 mph.
The record today is an awe-inspiring 529.77 km/h, held by German skydiver Marco Hepp, according to officials with the Fédération Aéronautique Internationale (FAI), also known as the World Air Sports Federation.
While the record was set in October 2022, a new study into the aerodynamics of the sport reports that humans could freefall at up to an average speed of 600km/h within the next 10 years.
A team of aerospace researchers at Germany’s Aachen University of Technology recently published the very first research paper on speed skydiving, “Numerical analysis of the flow around a speed skydiver” by S. Schölzel, A. Henze and A.-M. Schreyer.
The researchers’ findings could aid equipment manufacturers in creating more streamlined gear, according to FAI officials.
Marco Hepp contributed to the study, being interviewed about the sport and providing images and his own jump data. The main objective of a speed skydiver is to reach the highest possible free-fall speed over a given phase of the jump.
“It is simply fantastic that this very cool sport attracted the attention of aerospace engineers,” said Narit Pidokrajt, who is a physicist, skydiver, and alternate delegate for the FAI Astronautic Records Commission (ICARE) and FAI General Air Sports Commission (CASI) for Sweden.
He explains that a skydiver is subject to gravity, which pulls the skydiver towards the ground, and accelerating their journey towards Earth. In a classic belly-to-earth skydiving position, the athlete creates an area of air resistance, and by changing body position, can reduce this to move around in the air and create formations, flipping and spinning in the air. Speed skydivers, in their head-down position, aim to minimize the air resistance to travel as fast as possible. This is what the researchers wanted to study.
While studies have previously been made into standard belly-to-earth position skydiving, this project is the first to analyze speed skydiving, in which the athlete adopts the head-down position. The team from Aachen University of Technology, which is well known for aerodynamics and aerospace research, initiated the project by defining the reference conditions and identifying the flow regions that caused most drag.
They discovered that “several parameters affect the achievable speed, most importantly the skydiver’s mass, body shape, posture and orientation, but also the jumpsuit properties, which all interact with the Earth’s atmosphere to create drag.”
The results found two areas of large-scale separation that strongly contributed to drag: The athlete’s neck and the rear end of backpack.
In the second stage of the research, the team designed different configurations to change the drag areas, aiming to discover how these modifications affected the results and show how reducing the drag could enhance a skydiver’s performance.
Three modifications were tested:
- Backpack: “We applied the principle of boat tailing to decrease the downstream wake region and allow the flow to remain attached.”
- Spoiler helmet: This was “designed to shift the separation on the helmet downstream to reduce separation on neck and shoulders.”
- Neck brace: “The neck-brace configuration reduces the volume of the re-circulation area by thickening the neck and thus filling in the neck cavity and smoothing the outer contour.”
The team found that the two latter configurations which reduce drag around the skydiver’s neck yielded the best results.
They concluded that equipment development could take a two-stage approach: First, investigating the reduction of drag around the neck, which made the biggest impact, then fine-tuning the equipment by reducing the backpack drag.
You can see the full article, which was published in the European Journal of Mechanics/B Fluids (2023), here.