White Lightning was first conceived in 1977 as a club project by students at Northrop University. The only design criterion was to run at the highest possible speed. The final result was a two-person, three-wheel vehicle 6 m (20 ft) long, 760 mm (30 in.) high, and weighing 36 kg (80 lb). As it would be run only on a race track, the ground clearance was 13 mm (0.5 in.), the turning radius was 15 m (50 ft), and the visibility was poor.
You were speeding, boys …
White Lightning was the first Human Powered Vehicle (which includes all kinds of bicycles) to break 55 mph, which was the National Speed Limit at the time, and in the process also won the $3,000 Abbott prize. The riders receiving the mock speeding ticket were Jan Russell and Butch Stinton, the year was 1979, the place was Ontario Motor Speedway in Southern California.
Historical notes from Tim on bike development and testing …
We tested models in the wind tunnel, rather than do full scale tests, because it was easier and much less expensive to try various shapes and modifications. In other words, we obtained a lot more data than if we had done full scale test.
Nowadays, I wouldn’t even do wind tunnel tests, but use a computational fluid dynamics program on a powerful PC.
The thing about wind tunnel tests is that it tells you very little about real world overall performance. In the real world, bike performance depends not only on aero drag, but also rider power output, frame/drive train efficiency, and handling. Also, aero drag varies greatly in cross winds, and can greatly increase if the vehicle is not properly designed. Most published wind tunnel tests do not take all these factors into consideration; thus the results are only useful to compare downhill speeds with no cross winds. Only a very small part of most bike rides are done in these conditions.
The White Lightning which I developed in the wind tunnel 22 years ago only raced on flat tracks with large corners, and in low wind conditions (required by the rules). In real world riding conditions, the other factors are as important as wind drag, if no more so. This is why our F-40 and F-90 hold numerous long distance open-road records, they take ALL these factors into consideration.