Human Powered Vehicles (HPV’s for short) do what they say on the tin. What power and speed they reach however is far from ordinary. This is no different for Aim 93 and their particular goal in mind.
Made up of students and designers at London South Bank University their goal is simple. Break the human-powered land speed record for an HPV. In particular, the men’s 200 metre flying start speed trial.
Much as world tour riders often evolve from time trial specialists to climbers from rouleurs to puncheurs depending on what sparks their interest and indeed their changing physical attributes, so too does the Breakaway Digital blog.
Covering everything from road racing to world championship para track cycling we now turn our attention to record-breaking.
Breakaway digital love a bold and bonkers project and so wanted to get involved in their journey.
Aim93 is a project that hopes to break the human-powered land speed record. And, as the name suggests, reach the eye-watering speed of 93 mph.
A little bit about the team,
Headed by Barney Townsend a senior lecturer at the university and passionate designer and engineer. Barney has worked on projects including kitesurfing equipment and medical devices. Now he has turned his attention to breaking the world land speed record.
The team around him know what to do. Each student working on the project is tasked with completing their own parts of the HPV. The man behind the shape of the slippery vessel is Glen Thompson.
That is just the design team. But what about the riders Noah and Russel?
Noah a London fixed gear crit specialist, Russel the recumbent rocket. Both have plenty of experience racing bikes and also understand what it will take to ride the record attempt. They have a clear plan in mind and amazingly seem unphased by the speed, instead, they are eager to get on with the project and get riding.
The goal of 93 mph is not a number plucked from thin air but instead carefully calculated through advanced Computational Fluid Dynamics (CFD) and computer simulations that take into account the altitude and course conditions of Battle Mountain, Nevada.
Glen Thompson the chief aerodynamicist has been working on the shape since 2015, refining the shape through an iterative process.
Because the goal of 93 mph is a theoretical best possible result if all the factors are perfect, it means that every single aspect of the bike needs to be refined and optimised.
With this in mind, it means that the riders need to be prepared. They have undergone physiological testing to ascertain their VO2max values and as such create a bespoke training programme that will prepare them for the 8-minute effort that they predict the 5 miles will take.
To replicate the 1400 metre altitude of Nevada the riders are training with a hypoxicator mask. This allows the riders to be adequately optimised because it is harder to push the same power at altitude compared to being at sea level.
The Boardman Performance Centre was chosen as the testing ground for the bike going by the name of Velociraptor.
Undeterred by the torrential rain outside the team moved swiftly and efficiently to set the bike up. Working alongside Blue Hippo Media who were filming for an eagerly anticipated documentary of the project I took the chance to ask the designers and riders some questions.
One of the most influential factors in creating aerodynamic drag along the surface of an HPV is the size of the transition zone, where the air goes from laminar to turbulent flow. Reducing the size of the transition zone should theoretically improve the aerodynamics, therefore meaningless power is needed to go at the same speed or a higher speed for the same power.
To illustrate this and find where the transition zone occurs the team attached pieces of wool to the side of the HPV. When the wind blew it became easy to see the change in flow.
After testing the wool a ‘trip strip’ was attached at the line where the CFD had predicted the transition zone would be. This, in turn, was designed to reduce the time the air spends in transition and if possible make it jump straight to turbulent flow.
With the tunnel winding down after a busy morning we needed to check over the numbers and have a debrief, not forgetting an all-important sandwich of course.
Initial impressions of the data suggest a slightly higher drag force than predicted. Potential reasons for this could be the sanded finish or perhaps the custom method of attaching the HPV to the wind tunnel floor, which doesn’t normally welcome machines of this shape.
An obvious point of discussion was that when compared to Russel on his recumbent bike in the same wind tunnel the HPV produced staggeringly lower CdA numbers.
Perhaps not a surprise to many it did tempt me to make a custom enclosed pod for my commuting bike for the next time I am late for work and need to shave off a few minutes on my way to the Breakaway HQ!
To my surprise whilst debriefing, we had the pleasure of welcoming the founder of the tunnel himself Chris Boardman.
A man clearly passionate about groundbreaking aerodynamic design ideas and projects that stretch the possibilities of human speed and performance. It was brilliant to hear his take on the project and design philosophy.
The overall feeling from the day was one of measured positivity. The drag values were slightly higher than expected but the team now know exactly what they need to do over the next two months in preparation for racing in September.
One thing is for certain, we are very excited to see what happens next so watch this space.