The 2015 F1 season was the first season following the departure of Bernie Ecclestone's management team and the commercial presence in F1, after a series of scandals leading to bias in choosing locations for new or returning races.
McLaren announced a new long term partnership with Honda after a long term agreement with Mercedes ended. Oil company Mobil1 bought what shares Mercedes had in McLaren and also a bit more to come title sponsers.
In order to attract more young drivers to its program, EQ8 (who already sponser the GP2 team) purchased a 10% stake in Caterham. This meant that young drivers now have a link between the two teams.
After a not so good season with Ferrari the previous season, Marussia looked for a new engine supplier. Having already using wind tunnels at McLaren, the team looked next to Honda, who were interested in supplying engines for the team.
When there was only three bids received (which was then down to two after the Romanian's backed out after financial issues), the FIA agreed to allow both teams to race.
Of these teams, Ford bought a 25% stake in Haas in responses for using there engines. Toyota meanwhile bought a 40% stake in Stefan to supply the team with engines, technical support and more, while Stefanovic would run the outfit.
After calls that F1 was becoming too machinery and not enough driving by the drivers, several driver aides were removed. These include DRS, ERS, telling the driver to change gear, automatic gear boxes, display telling the driver's time and more. The only things that remained was the radio. Instead, a new manual gear box with a gear leaver was installed along with a rev counter and a speedometer. There were no little buttons to turn the engines up or down or anything like that. Only the electronic braking devices remained.
The number of engines that could be used was reduced to four engines. The penalties for a new engine were given as 10 place penalties on the following race's grid (as they were forced to start from the pitlane) followed by a ten second stop and go penalty.
Refuelling was reintroduced after a series of scandals the previous year in the fuel flow rate rules. However, they were only allowed to put 230 litres in the car for each race. Anyone that uses more will be disqualified.
Qualifying has changed to having two 30 minute sessions where all drivers are allowed to take part in both sessions. The driver's best time will be taken to give their grid position.
After calls that the 107% was just a rule that was non-existant, the FIA put in that anyone failing to pass the 107% rule in dry conditions will not be allowed to race. In wet conditions, this rule is at 125%. If a driver fails to set a time, then the rule is applied to the driver's FP3 time.
The two new teams of Haas and Stefan will not be allowed to race until the first european race of the season due to allow the teams extensive testing to remove reliability issues.
If a red flag is issued in a race, then drivers will not be allowed to change tyres, refuel or make any other changes to the car.
After further calls that drivers weren't fighting hard enough to get points, the points have gone back to 10–6–4–3–2–1, apart from the final race, which will still have the 25–18–15–12–10–8–6–4–2–1 system.
The system of "Jokers" have been banned. This means that no changes can be made in curfew hours without a penalty.
Car numbers were put back to the previous system after the new system was unpopular with the fans.
The number of grand prixs per season has been increased to 25