Originally Posted by SteveHansen

The notion of a hybrid train is interesting.

It really could be extended to other kinds of vehicles. Most cars get dramatically better FE if they "draft" the one in front. The only problem is that drafting is quite dangerous because the braking reaction time is greater then than the following time. IF the braking reaction time could be reduced to (very near) zero by an automated sensor, that problem would be solved. Then, if that sensor could also be linked to the cruise control, it could regulate the following distance to just a few feet. With computerized cruise control and brake controllers, the current hybrid technology seems to be missing only the sensor and a little bit of code to control it.

If the entire fleet could have this sort of technology, the net result could be greatly increased highway capacity, reduced incidence of rear-end collisions, and increased fuel mileage across the entire fleet. If the sensor and brake controller could also detect pedestrians and such, it might solve that other pesky problem also.

The only problems would be that the person in front would control the speed for the entire line of cars, but the slow drivers on their cellphones do that now anyway. No one would have to go faster than they want, because you could always slow down. You would just end up being the lead car in the train.

The only real problem is transition. How do you introduce this technology safely into a fleet that doesn't have it? That requires that the new technology be backward compatible with older cars on the same road, and so the new sensor could not depend on any feature being present in the car that it is following. The sensor would have to be a stand-alone thing. But we have various kinds of radar and low-power laser sensors now that could fit that requirement... so it seems very doable.