In the latest Racecar Engineering there is breakdown of the projected weight of the unbuilt Caterham CT06 car (page 50). Due to Caterham's demise the design wasn't built but I presume with CAD etc and prior car knowledge they could estimate component weights accurately.
Some of the weights didn't surprise me like 14.45kg for the huge front wing assembly versus 6.1kg for the rear wing. However some were higher than I expected, in particular the monocoque weight is 99.91kg plus another 26.8kg for the floor.
That is 126kg just for the main chassis which has a plan area of about 6-7 sq. metres. I am surprised at this as the Lotus Elise aluminum chassis is often quoted as 68kg and it has to meet all road crash levels without the benefit of a large cross section or roof as in bigger cars. I know teh crash test on F1 cars is very severe but I thought the nose cone did most of the work to protect the driver legs
In racing terms the lightest chassis I can recall is the Lotus 77 quoted by Tony Southgate as 52LB, or 24kg.. It was smaller than the Caterham chassis and I doubt any modern driver would be happy with it's fragility but 1/4 the weight of the CT06.
I wonder if the 99.91kg includes the bag tank as it isn't listed separately , but all the pedals and steering are thus they are not in the 99.9kg chassis.
Any thoughts from the chassis structures guys here please?
A few thoughts:
First about the weight of that Lotus 77. Keep in mind that the monocoque height was nowhere near as high as with the current cars. I am not sure how the fuel cell of the 77 was built up, but I don't think it was already a single tank behind the driver. Anyway there was hardly anything on or part of that monocoque that extended above hip bone height ! Mario and the other drivers who drove a Lotus 77 only had the cockpit cowling for impact protection apart from the dashboard construction on the car.
The coques of the past were flat sheet metal with some honeycom in between for strenght and, as pointed out, low. Hae a look on the current cars with all the curvations etc that are `required` because of aero purposes and how heigh up from the floor the go upwards to make up the protective cell for the driver.....
Finally, it was a Lotus and knowing the weight save obsession of Colin Chapman... enough said.
Then, with the downforce generated by the floor, better make it a sturdy floor that doesn't bend or flexes in a manner unwanted or make provisions it does deform in a manner you want it. But with the current freight train long cars, that makes the floors awful long and wide as well, When such areas need to be sturdy and strong, I am not at all surprised at all that the basic part of the car weighs in at such a weight already.
All that talk about corbon fiber being light etsc... But when you need lots of carbon fiber you eventually will end up with something that is way more heavy than you expected.
Look at that front wing contraption you list. Is it really that big compared with the monocoque? But it is a hefty 14+ kg already so.......
Edited by Henri Greuter, 20 November 2018 - 19:48.