How does drafting in racing work

In general, the more aerodynamic an object is, the smaller and weaker its slipstream will be. It works in real life. As people or other objects move, they leave behind a low-pressure area that is easier to move through. Cyclists racing in a velodrome travel as fast as possible, but the faster the bike goes the greater the drag.

To combat this, two or more cyclists can slipstream, or draft. It all comes down to aerodynamics of an object through a fluid note: gases, like air, are referred to as fluids. Slipspace is slower than both and also is not nearly as accurate.

Hyperspace is accurate enough for busy interstellar lanes and warp is accurate enough to drop a ship right next to another one without risk of collision. Speedy slipstreaming This drag can slow the vehicle down, even when travelling within a controlled environment — such as an indoor kart track — with no wind.

As the vehicle moves through this drag, it creates a partial vacuum behind it, known as a slipstream. Can I wear my own helmet? Yes, as long as they are full face helmets and meets ISO standards. All helmets must have a clear visor. Wait until you hit a straight part of the track before you brake. Begin braking in the straight area just before the turn. When you first start go-karting, work on mastering the basics of driving the kart.

If you want to improve your driving skills, practice often, time your laps, and learn the ins and outs of the tracks you drive most often. The truth is that go-karting is not only an enjoyable sport, but one that is also extremely safe for kids and adults alike. You can drift karts. But it may cost you the race. Drifting your kart can be a good way to get ahead… in Mario Kart.

From an engineering perspective, the multi-vehicle interaction is very complicated with all the vortexes in the wake. Add in changes to high pressure stagnation points and the conversation quickly turns into an engineering geek-speak-fest talking about coefficient profiles, the changes at various car lengths between vehicles, and the ensuing passing of the lead car.

Bottom line is: different cars have different wakes impacting how the draft works. A club racer should be aware of mixed classes on the track at the same time. Hopefully, you are on the track with cars of roughly the same size, shape, and power just to keep everybody involved safe , but if by some odd chance you find yourself in a sedan and spot a Formula Vee up ahead, don't even think about drafting! Back to the question of "At what speed and how close do you need to be to get that tow?

One car may start to pick up a draft at 60 to 70mph or less where another may not pick it up until 90, or more. Likewise, how close to the leading car you need to be for it to work is also a function of the speed. The faster you go, the longer the wake holds its form like a "Separation Bubble" and the further back you can pick up the draft.

I think he was kidding, but what happens at mph is amazing. On the other hand, I had an IRL driver tell me that he had to enter the draft at a certain angle or he thought it hurt him.

Maybe in his case it didn't hurt, it just did not help as much. Let's wrap this up by addressing the "What is the best way to draft? When I'm not wearing the engineer's hat, but wearing the coaching hat, I try to get drivers to recognize that there are several points ahead of the car while on the track. First is the control point. The control point also moves further out the faster you go. Next is your mental focal point ahead of the car, not just visual, but mental.

If at any time your focal point is between the control point and the front of car for more than a nanosecond, you are in danger of something unpleasant happening and that's what I call the Danger Focal Zone. Important point: your focal point needs to be as far down the track as possible! As the wind whips around the house the pressure outside of the house is lowered, and the pressure inside the house becomes comparatively higher.

Soon the pressure differential is enough for the windows to shatter out from the higher interior pressure. Race cars essentially turn the airplane principle upside down. Air flows around the car as it screams around the track and each minute flow of wind along the hood, windshield, fairings, doors, spoilers and air dams has a subtle effect of increasing or decreasing the air pressure on every surface of the car.

But, overall, there is more pressure coming over the top of the car than underneath. This sucks the car downward toward the track surface, allowing it better handling on the turns and a more stable ride. This is referred to as negative lift in aerodynamic-speak and racers typically seek to increase this effect.

At speed, downforce can add the equivalent of 1, to 1, pounds to kilograms of downforce to the tires. On smaller tracks with fewer straightaways a car is tuned to have even more downforce to keep it stuck to the pavement and handle the turns better. Drag is the downside of downforce. There are essentially two kinds of drag -- friction and pressure.

Friction drag is the contact of air and the object moving through it, like a race car. Pressure drag has to do with the low pressure created as the air moves around the object. NASCAR has become one of racing's leaders in tweaking drag and constantly strives to reduce this effect on its cars.

Kurt Romberg, chief aerodynamicist at Hendrick Motorsports, said as little as one percent drop in drag is worth an improvement of about 10 positions on the starting grid at Daytona. Romberg works on all their cars. The draft is when downforce and drag, as well as a few other factors, come together on the track. Drag and downforce are affected by airflow coming off of cars driving close by -- usually within a car length, though effects can extend up to three car lengths away.

In common drafting situations, the lead car breaks through the air in front of the line, or pack, and reduces the friction drag for trailing cars. But the trailing cars play a role as well. In addition to friction drag, there is pressure drag created by the low pressure behind the leading car. By staying close to the lead car the trailing car interrupts that low-pressure system and cuts down on its effects. The end result is about a 5-mile per hour 8-kilometer per hour increase in speed for each car in the draft.

This increase makes having a drafting partner at superspeedways critical. Racing legend Junior Johnson is acknowledged as the first driver to use drafting as a competitive tactic. In , at the second Daytona , Johnson was behind the wheel of an under powered Chevrolet in competition with several dominant Pontiac cars on the track at that time including one driven by Bobby Johns.

Johnson discovered during qualifying heats that if he pulled up close to the competition, within a few inches, he could keep pace with the bigger and faster vehicles. This was the beginning of the technique of drafting. The same physical forces allowing Johnson to keep up with the competition led to Johns' defeat. Johns reportedly was in a drafting position with another driver and the lower pressure from the slipstream was so intense it sucked Johns' rear window out of his car.

Johns spun out and crashed and Junior Johnson won the race. NASCAR imposes strict rules on engine power, engine components, body design and composition so no one team can gain too much of an advantage.

The end result is a game of very small numbers and percentages and those numbers play out in body design and driving skill -- which, of course, includes drafting. Daytona and Talladega are two superspeedway racing venues where a draft-savvy driver can really shine.

Both tracks offer banked curves and long straightaways where a driver can push a car to its upper limits. It's for this reason that tracks require restrictor plates and other safety measures to limit top speeds. Because of this, capable drafting is often a key to success. Traditional restrictor plates drop the overall power of the cars by about horsepower [source: Boone ]. Plates were first used in the s to even the playing field between larger and smaller engines, as well as a safety measure as the tracks became larger and the cars became more powerful.

In , NASCAR driver Rusty Wallace tested a car at Talladega without a restrictor plate and reached a reported top speed of miles per hour kilometers per hour on the backstretch and had a one-lap average speed of mph. Despite the use of restrictor plates, NASCAR drivers often reach speeds of more than miles per hour kilometers per hour.

This is in large part due to drafting where an understanding of the physics involved allow drivers to help reduce drag and gain a few more miles per hour kilometers per hour in the process. At smaller tracks, like Bristol Motor Speedway in Tennessee where drivers turn second laps, the constant curve of the track means less opportunity to draft. Here, engines are allowed to run full power and downforce becomes critical. With more than horsepower being produced in some races, downforce is maximized to stick the car to the track.

At superspeedways, downforce is purposely reduced since the track layout requires higher speeds on the straightaways. The adjustments become a bit of a balancing game: Less downforce means greater straightaway speed, but less grip in the turns, and more downforce means improved grip in the turns, but slower straightaway speeds. As you can imagine, finding the perfect adjustment can prove difficult. Until recently, the mix of track layout, engines, tires, drivers and strategies, drag and downforce required most teams to field several cars, especially for Sprint Cup series competition.

The initial plan called for the design to be featured in 26 of the 36 races on the NASCAR schedule and then bumped up to permanent use in the racing season. Instead, the new design was raced in all 36 races on the schedule and is currently the only car design NASCAR allows to race.

The rear wing replaces the traditional spoiler and the front splitter is a thin horizontal piece under the front bumper that increases downforce. Teams will be allowed to adjust the angle of attack on the wing and the position of the front splitter to custom tune the car's performance on different tracks. Hill said the changes have a serious effect on the car's wake characteristics and therefore on the drafting potential of the car.

The end result is a car that's harder to pass and harder to draft. Drafting strategy involves more than simply knowing where to place your car on the track , and it often has less to do with aerodynamics and more to do with driver's knowledge of the competition's mind. Drafting strategy is where a race becomes a mental challenge as well as a battle of speed and guts.