Slipstreaming reduces drag for horses, too

In the lead-up to the 2014 Melbourne Cup, RMIT researchers have revealed a tip for those jockeys looking to reduce drag on a horse during a race.

The team conducted wind tunnel simulations in RMIT’s Bundoora wind tunnel, using toy models that are exact miniature replicas of a racing horse and jockey. They found that jockeys who take advantage of slipstreaming, or drafting, by running their horse behind or alongside others can reduce aerodynamic drag force by up to 66% - saving their horse critical energy.

The research showed the impact of different horse packs on drag (on average):

• Two horses in front of one horse: drag of trailing horse reduced by 66%
• Four horses in a row: drag of last horse reduced by 54%
• Two horses running closely behind each other: drag of leading horse reduced by 6.5%, drag of trailing horse reduced by 38.5%
• Five horses side by side: drag of centre horse increases by 25%

From these principles and further results, the energy expenditure can be calculated throughout the race of each individual horse, as well as the overall energy savings when slipstreaming.

The study’s co-chief investigator, Professor Franz “Tino” Fuss, said slipstreaming is a standard strategy in sports such as cycling and speed skating to save athletes’ power and energy. In a horse race, he said, jockeys can use the same principle.

“Our research for the first time quantifies how much drag is reduced through different slipstreaming tactics in a horse race,” he said.

“Jockeys, trainers, punters and betting companies should keep these findings in mind during the big days ahead of the Spring Racing Carnival.”