Eli5 How can formula 1 drivers pass each other on straight always?

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Wouldn’t they all be flooring it? If the lane is straight how does one driver speed up and pass another?
Edit: straight aways

In: Engineering

13 Answers

Anonymous 0 Comments

Car engines don’t make power at a constant rate, their power output is always changing depending on the RPM of the motor. If you accelerate an F1 car as fast as possible, it’s rate of acceleration is not constant, it gets faster and slower at different speeds.

So if you had 2 identical cars with identical performance, but one hit the accellerator 1/10 of a second earlier than the other coming into a straight, it comes into it’s power band 1/10 sooner, which pulls that much harder, which results in opening up several car lengths compared to the other driver. So even with all things being equal, the speed with which you exit a corner, especially onto a long straight, matters more than your speed through the corner. The faster you come out of the corner, the faster you will accelerate down the following straight, even if the line you take is slower or not ideal. As long as you exit fast, that’s all that matters.

Another way to pass on a straight is to use aerodynamics and drafting to let the cars ahead of you break the air up like a wind breaker, and you get into this air by driving closely behind them, and it’s much less drag on your car, allowing you to drive faster than the car in front. Think of it like the car in front is doing all the work of pushing that air out of the way, and the car behind doesn’t have to push as much air out of the way, letting more of it’s power go to speed instead of fighting the air.

So cars will use this reserve speed at the right moment to sling shot around the driver ahead of them, maybe even chaining several of these together slingshotting from car to car, gaining more and more speed, and seeming to suddenly pull ahead of the pack. Eventually they will run out of cars to draft, and others will draft them as now they are the wind breaker and slow back down.

In general groups of cars travel faster than they would by themselves, so it actually benefits everybody to have opponents close by even behind you as it reduces the wake drag on your vehicle which lets even the car in front go a little faster than normal, just not as much as the drafting cars boost.

Finally using new technologies such as KERS (Kinetic Energy Recovery System aka regenerative braking) the drivers have a short amount of power boost on demand they can use for passing. It reuses some of the stored braking energy, usually in the form of a flywheel that was spun up. It only lasts a second or two but it’s basically free power that gets recharged during long braking.

Anonymous 0 Comments

1. **Driver skill** does influence speed on the straight. Not by pressing the gas pedal harder like in the movies, but in the “exit” of the previous corner. Shockingly small variations in car placement allow you to press the accelerator sooner (or later) when you’re on the way out of a corner, and these small differences result in reaching high speeds sooner. The differences between drivers are small, but at top speed 0.1s might be 10 meters of space, which can be enough to lock in a pass. But most of the driver skill that leads to an overtake on the straight occurred in the previous corner (or several corners), and is often not shown on tv.
1. **Tire grip varies**, and grippier tires allow more aggressive acceleration on corner exit. At different points in the race, cars run more or less grippy tire “compounds”, and newer tires grip better than older ones. Deciding what tires to run when is called tire strategy, and for a given pair of cars can result in one having the advantage near the start of the race, and the other having the advantage at the end. Driver skill influences how quickly they wear out their tires as well.
1. Not all F1 cars are equal, **some have slightly stronger engines** (many non-F1 racing series do have ~equal engines, but in F1 they vary in power).
2. Not all F1 cars are equal, **some drag more against the wind**, either in an attempt to use the air to be faster during turns or just because they’re less well designed and have more drag.
3. The car in front pushes the air and leaves a “wake” behind it. A close following car experiences less wind drag in this wake, and goes a little faster than it otherwise would as a result. They call this a “tow” because it feels like **the front car is pulling you along**.
4. Modern F1 rules give each car a special rear-wing flap called **DRS (Drag Reduction System)**. In order to make overtaking easier and make racing more exciting, the rules allow the trailing car to open that flap and reduce drag in at certain places on the track when they’re close enough to the car in front that the extra speed might help them complete the overtake.
5. Modern F1 engines don’t have constant power output. They have batteries and energy recovery systems that let them **boost the engine power in short bursts**. If the trailing driver has somehow conserved their battery power while pressuring the leading driver to spend theirs, they’ll have a temporary but significant advantage in top speed if they juice up their electric systems for the overtake. Various bits on the car can also overheat as well, which can also lead to temporary variation in performance as drivers are forced to drive conservatively to let temperatures recover. Managing all these temperature and power resources while driving as fast as possible is a big differentiator in driver skill.
6. Also they do actually [press on the gas pedal a little extra](https://images-wixmp-ed30a86b8c4ca887773594c2.wixmp.com/f/6a56e759-c201-4084-9a4f-f1af42bdcfa3/db1n4yk-85aae30c-dfe8-498c-ac21-5925353c2ddf.gif?token=eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJzdWIiOiJ1cm46YXBwOjdlMGQxODg5ODIyNjQzNzNhNWYwZDQxNWVhMGQyNmUwIiwiaXNzIjoidXJuOmFwcDo3ZTBkMTg4OTgyMjY0MzczYTVmMGQ0MTVlYTBkMjZlMCIsIm9iaiI6W1t7InBhdGgiOiJcL2ZcLzZhNTZlNzU5LWMyMDEtNDA4NC05YTRmLWYxYWY0MmJkY2ZhM1wvZGIxbjR5ay04NWFhZTMwYy1kZmU4LTQ5OGMtYWMyMS01OTI1MzUzYzJkZGYuZ2lmIn1dXSwiYXVkIjpbInVybjpzZXJ2aWNlOmZpbGUuZG93bmxvYWQiXX0.a4l-9q-Jt45mXdcmWdy8x5KDwXi38RpM1H_8Pq3IAuc) and legend has it this does help if you believe hard enough.

Anonymous 0 Comments

Slipstream and DRS.

F1 aerodynamics produce massive amount of downforce to keep the car sticks to the road when going through corner at high speed. However, this downforce also creates drag. On straight lane, you don’t need that downforce, you care more about the speed. So you’d want to lower the downforce to lower the drag, which make your car goes faster.

F1 cars also creates “wakes”. Simply saying, wake is a turbulent air behind the car. This turbulent air usually have lower pressure than the ambient air around it.

By going behind this low pressure air, your car will have lower downforce, and in turn, lower drag, so you can have higher top speed. This is called slipstreaming (or drafting in NASCAR). This is also why you’ll see driver tailing their opponents, to take advantage of the wake and gain speed.

Then there’s also DRS (Drag Reduction System). It simply opens up the rear wing to reduce the drag from the rear wing. DRS can be only activated on pre-determined straights, and when the driver is close enough (less than 1 second) behind another car.

TL;DR: by going behind the opponent, the chasing car will have lower drag and can go faster. If they’re close enough, the chasing car can also have DRS to even reduce the drag.