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Sorry I wasn’t clear enough. A reference area is used in the calculation of Cd to make it dimensionless. On a car (and aeroplane, I believe) the reference area used is the projected frontal plan area. That means Cd is useless in comparing actual drag of 2 vehicles unless the reference area is...

Producing the low drag without introducing lift is important for grip and handling. Generating downforce anywhere but from the underside always induces drag IME and not worth doing for a road car though it will make a big difference for a trck car, though probably not as much as sticky tyres...

Cd does not include frontal area. It is a dimensionless coefficient, as you write, and frontal area is one of the dimensioned parameters used in its calculation. The drag force is proportional to it and multiplied by the "reference area" which is pretty well always the frontal area, which is the...

No there is none.

I have only considered the aerodynamics of racing cars and a small number of road cars. Most SUVs and Trucks are are aerodynamically rubbish anyway so probably any difference caused by ride height will be a small proportion of the huge number that they inevitably have. Do you use the expression...

I was amused by that. The young guys doing it now have too narrow an experience and use too many static analyses that give no worthwhile information about dynamic response. The only 2 blokes I know who worked on cars the last time we had ground effect who are still working in F1 today are...

I have thousands of hours experience wind tunnel and CFD testing cars, mainly Formula 1 but some road car too. A frequent simplification is often made, which is not to rotate the wheel but IME the flow field around stationary wheels and the ground not moving relative to the car makes big flow...

Ground clearance is a low order influence on efficiency as long as the underside isn’t too rough, which is usually ok on an EV because it is a battery not drive shafts and exhaust. The big thing ruining highway efficiency is the shape and also frontal area, which is dreadful and huge...

The 0-60 time is, for me, literally of zero importance. I have never done a drag race in my life because where I live there is almost never a traffic light with 2 lanes going the same way and on the rare occasion there may be I have forgotten doing anything like that was an option. The...

I think if this were actually true (It isn’t IME) there wouldn’t be a majority of appalling handling cars!

I am interested by the experience of people living in or frequently visiting places with poor or absent phone signal. It is possible Porsche has been storing all the data and preferences on their cloud rather than in the car which would explain a lot of the "software defects" if true. And be a...

Touch screens are great for versatility where a lot of functions are more easily distributed through a series of screens but they are the master of the unwanted selection in a moving car IME, particularly in countries where we have the screen on our left and are right handed. The very worst are...

IMO that is a narrow view that works badly some companies. It is an understandable desire if you are a stock market gambler but two good engineering companies here in the UK went to the dogs after they went public and took this attitude. I happened to know the MD of one of them and he said he...

Rubbish.

It is already happening. Large swathes of central America have turned to dust bowls and people are starving or migrating north towards the USA. Ditto in Africa where people are migrating north towards Europe. This time it isn’t nature that has chosen us for extinction, we look likely to be the...

I have seen all that rubbish before. I do think the media exagerate a bit but after 30 years of successful propaganda I think most non-scientifically people, and that is the majority, are not going to be swung by facts. Doubt has been deliberately sown by oil companies on purpose for decades...

In fact the reality is that rich fossil fuel companies have been funding climate change scepticism for 30 years and many people have been convinced. Real science does not agree with your opinion I am afraid though I see this “it used to be hot sometimes 100 years ago” propaganda often.

Really I don’t think we will do enough to avoid catastrophic population collapse as the climate changes. The question is when and which species thrive in the conditions extant - there will be some, obviously. The whole idea of “save the planet” is daft, the planet continued to evolve after the...

This is true but only the most backward countries are still using mainly carbon fuels to generate electricity and EVs still remove the pollution from city centres and dump it out of power station chimneys instead, bad but not as bad.

There is a process to synthesise aviation fuel very like that refined from oil from CO2 extracted from the air and using solar power to power the process. I don’t know much about it but it is being developed from an academic’s idea to a process to create R&D quantities of the fuel and studies...