Modern Day Engineering
Modern day bobsleighs are hugely innovative and use the latest technologies, aerodynamics and materials to increase the speed of the sled. Other nations have their own sled development projects such as the German team who have been extremely successful using their self-made government funded sleds which give them a significant advantage over the rest of the world. Many motor racing companies have also tried their hand at creating their own bobsleighs such as BMW, McLaren, Ferrari and Hyundai to name a few.
With many races being separated by just tenths or even hundredths of a second many nations are trying to get the technological advantage. However, with the cost of a new 2-man sled reaching £50,000 and a new 4-man up to £100,000 it's an extremely costly endeavour.
The sled's themselves are relatively simple as many rules limit their speed as sleds that are too fast will be too dangerous to control. The cowling of the sled is made out of carbon fibre and fibreglass, the design of this is important for aerodynamics and the effective absorption of vibration. The frame is made out of steel which often flexes slightly as the sled navigates the corners and the relationship between the frame and cowling is very important to take as much speed down the track as possible.
The runners on the sled are arguable just as important as the sled for speed down the track and are effectively the tyres to the bobsleigh which are made of steel and are in contact with the ice. Runners vary a lot and choosing the right runner for the right condition can be very difficult. The ice temperature, air temperature, humidity, frost, track condition and the characteristics of the track all play a part in runner selection. A World Class set of runners can easily cost in excess of £10,000.
Runners are made out of standardised steel which is provided by the International Governing Body so nothing can be changed with the material just how the runner is shaped. The width of the runner is important as the wider the runner the higher the potential it has for speed as it will dig into the ice less which creates less friction. However, because it creates less friction the steering becomes less responsive and there is a higher probability for skidding which can eat away a lot of time if the driving lines aren't perfect. The rock (the bow in the runner) can also be changed and is especially important for deciding what runner to use on which track.
On race day the runners are polished to a mirror finish to reduce the friction on the ice as much as possible. This usually takes a lot of time but the differences are huge when compared with an unprepared runner.
The weight of the sled is strictly monitored because bobsleigh is a gravity sport. The higher the total weight of the sled the more speed you will pick up down the track.
The 2-man sled has a minimum weight of 170kg and a maximum weight of sled and crew of 390kg
The 4-man sled has a minimum weight of 210kg and a maximum weight of sled and crew of 630kg
To be effective at the start you want the lightest sled possible to get it moving but when everyone is inside you want the sled to be as heavy as possible to get as much speed down the track as you can. This is a very tricky balance to accomplish.
The weight distribution is also important. More weight further back in the sled will put more force onto the longer rear runners which will minimise skidding. Also being as low as possible in the sled is significant not only for aerodynamics but a low centre of gravity to increase the stability of the sled.
A bobsleigh race suit is made from Lycra because it’s light and tight-fitting. The material and design of the suit aid aerodynamics and prevent athletes getting their clothing caught on any part of the bobsleigh when loading at high speed.
A bobsleigh helmet is effectively a standard motorbike helmet. A helmet must be worn by all the athletes in the bobsleigh, regardless of their position in the sled.
Ice spikes are absolutely essential when it comes to moving the sled as quickly as possible from a standing start. These spikes are a unique piece of equipment to bobsleigh and skeleton which are designed on a similar basis to a sprint spike but feature over 400 needle spikes rather than the traditional six or nine on their athletic counterparts. The ‘brush spikes’ under the front part of the foot help give maximum grip while sprinting on ice.