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!
During drafting, as you come up to the leading car, it will move into that Danger Focal Zone. Here, the lead car is taking up a good portion of your field of vision and can become a distraction.
You may have a tendency to focus on the car ahead of you target fixation as mentioned earlier rather than beyond your control point. In this case, drivers have been known to follow another car straight off the track or straight into a wreck. This brings up the need for OODA loop strategy the decision cycle of observe, orient, decide, and act , developed by military strategist and USAF Colonel John Boyd when drafting and other driver coaching facets beyond the scope of the drafting question, but this may be a good subject for future story.
On a final note, when drafting, you should look through, around, or visualize through the lead car to stay on that all-important focal point.
Twitter: Autowareinc. The front car creates a low-pressure area -- a draft -- that essentially acts like a vacuum and pulls the back car forward. Add another car behind the trailing car, and the effects get even more pronounced [source: Tierney]. Cross-country skiing and running use variations of drafting, too. Use the left and right arrow keys to control your car.
Personal interview. Junior Johnson went from narrow escapes from the feds to narrow escapes from fellow stock-car racers. Hypermilers go to more extreme measures, too, like taking out every other seat in the car except for the driver's and not carrying a spare tire or a vehicle jack. Usually the cars following aren't wide open throttle like the lead car of the draft is, UNLESS they are bump drafting. That's where we take a look at the more "sophisticated" side of drafting. You earn points by drafting a team of drivers and they accomplish objectives on the track.
Pearson was reportedly worried about a slingshot maneuver from Petty and at the last minute allowed Petty to surge ahead. And if a driver makes a mistake and falls out of the drafting line it could spell doom for their chances in the race. Find out why Daytona qualifying is so complex at HowStuffWorks. 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. The end result is a car that's harder to pass and harder to draft.
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. We take a look at the importance of drafting in cycling. 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.
The lead driver can step on the brakes, come within inches of the following driver, and deprive them of the air needed to cool the engine. And just like that, one competitor goes down. The following driver can also pull a similar tactic, inching up on the car ahead in order to disrupt the flow of air over the lead car's body.
Remember, that airflow is critical for keeping the lead car's tires stuck to the track surface. Without it, and maybe with a little help in the form of a bump, the lead car can lose traction, skid into an outside lane and quickly drop 10 places or more during a race.
Teams, sometimes official but often an informal collaboration, use the power of drafting to rocket members past the competition, vie for the best track real estate and even steal the race lead at a moment's notice. All's fair, it seems, in love, war and drafting. The two-car draft is the most basic draft pattern and the one most often used by a team.
Pulling within a car length of a lead car benefits the trailing car by reducing drag. That same reduction also benefits the lead car as the presence of the trailing car reduces the pressure drag off the back of the lead car. The result is a speed increase for both drivers.
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