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Annex A13: Development Risk

In this Annex critical questions about the AUTOSHUTTLE concept are quoted. The answer gives a justification of the solution chosen in the actual concept as described and in some cases an alternating solution.

1. Why are the road vehicles not transported on open wagons instead of closed cabins ?

Air resistance of closed cabins is considerably lower. A convoy of 38 car-cabins uses 1,5 litres of diesel oil per 100 km at 180 km/h to overcome air resistance. With open wagons 6 l diesel would result. Environmental-friendliness would be wasted, electricity cost would increase.

Closed cabins are much safer. Fixing the road vehicles on open wagons would be complicated and failure-prone. Further on this is a good weather protection. A convenient climate control is achieved in most of the climatic regions by simple ventilation of the cabins uninterruptedly propagating at 180 km/h. At extremely high exterior temperatures pre-cooling may be achieved by solar cells mounted on top of the cabin. During the cold season preheating is possible within the cabin.

2. Why don't you avoid convoy formation during the trip, a feature which makes necessary development of a new operation control system and the non-moving point ? Cabins may run singly or convoys could stop at intermediate stations like a classical railway. The non-moving point could be avoided.

By the formation of convoys a significant decrease of air resistance per cabin is achieved. Energy consumption is mostly dependent on air resistance and is therefore reduced as well.
Without formation of convoys during the trip economy of the system is noticeably reduced. If entering or exiting a convoy is possible only during stops of the entire convoy like a conventional railway, a compromise between high station density and high averaged speed has to be found. If AUTOSHUTTLE had a few stations only, much less users would be expected, since many potential users would not find a station close enough. In case of many stations the users would avoid AUTOSHUTTLE due to the low averaged speed. Assuming a station frequency of 5 km, 2 min station stops and line speed 180 km/h, averaged speed would be 65 km/h with this classical operation concept. Energy consumption would be higher despite this low averaged speed. Acceptance would be very bad. Due to the low revenues cost-covering operation would not be possible. The development risk of the convoy concept therefore is justified.

3. Why don't you build AUTOSHUTTLE for lorries only ?

Because economy would be much worse and ecology would profit a lot less. AUTOSHUTTLE is able to transport any kind of road vehicle. Economy is the better, the more road vehicles are transported. Less than 15 % of the road vehicles on a motorway are lorries. Construction costs of the line are the dominant cost factor in the first years. These costs are almost independent of the number of transported road vehicles.

4. Why don't you operate AUTOSHUTTLE at less than 180 km/h ?

If you decreased the line speed, energy consumption of AUTOSHUTTLE would decrease too. But by the lowered acceptance of AUTOSHUTTLE and the consequent higher fraction of conventional road traffic total energy consumption and further nuisances of both means of transportation would be higher. 180 km/h is the best compromise for acceptance, energy consumption and economy for most lines.

5. Why don't you build AUTOSHUTTLE with ordinary railway wheels and rails ?

Wear and tear would be much higher. The ordinary system with wheel flanges could not be used on a non-moving point. Noise nuisances for the user and the line residents would be much higher. Energy consumption would be increased as well, since the chosen MAGLEV-configuration allows smaller cabin cross-sections and very low eddy current and air gap control losses.
However, the conventional railway technology for the support system would be an acceptable alternative in case of unexpected difficulties during the development of the MAGLEV-system.

6. Why don't you start cabins behind a convoy and let the starting cabins catch up the convoy ?

If starting cabins fails and is unexpectedly delayed, the convoy does not need to stop. Probability of an accident is lower. Energy consumption would sharply increase with this concept, especially for short trips. Cabins would have to run singly at over 180 km/h for a while in order to catch up the convoy. For a 10 km trip energy consumption would be 10 l diesel oil per 100 km instead of 3 l. Since AUTOSHUTTLE has very promising economical data, the high-performance safety system described above can be installed. Non-regular movements will be detected and convenient measures will be taken with a very high degree of safety. Probability for one train crashing into another is negligible.
However, the concept presented in this question may be an alternative solution in case of unexpected problems during the development of the system.

7. Why don't you provide separate acceleration tracks for starting cabins, which switch over to the main track at 180 km/h directly behind a convoy ?

Switching into an occupied track at speed is very safety critical. In case of small deviations to the regular operation, a fouling movement could develop with severe consequences. If the cabins participating in the rendezvous close up on the same track, small deviations would only lead to light bumping with mostly minor consequences.

8. Why don't you refrain from the fare system providing a special price for each type of car. Why not a single standard fare or, say, three fare levels ?

Because acceptance and economy would be much worsened by this measure. Many road vehicle drivers wouldn't use AUTOSHUTTLE because it is more expensive than driving on the motorway. Contrarily, drivers for which the fare would be much cheaper than driving on the motorway wouldn't use Autoshuttle much more than if the fare was only slightly lower than the self-driving cost. All in all, revenues would sharply decrease.

9. Are there margins in the revenue to cost relation ?

The financial study bears very high margins. Non-subsidised construction and operation is possible if only 30% change to AUTOSHUTTLE. The survey yields a changeover rate from the motorway to AUTOSHUTTLE of 96%. Therefore a higher changeover rate than 30% can be expected. Concurrent track guided systems generally can't be built without subsidises.

10. Why don't you build AUTOSHUTTLE with short-stator-motor ?

Because construction and operation costs are lower with long stator. With the high number of vehicles it is more convenient to have the major part of the motor in the track. Maintenance of the cabins is easier. There is no inefficient and unreliable motor power transmission to the cabins.
Principally, the short stator is a possible alternative in case of unexpected problems during the development of the long stator drive.

11. Why don't you design opaque cabins with windows ?

Because the chosen design generates the least agoraphobia. Different design may be used as well, e. g. if no scratch-resistant material could be found.

12. Is there no big fear for vandalism or other forms of crime in the cabins ?

AUTOSHUTTLE is little inviting for crime, because the criminal is at risk of supervision and a reception by police at the exit station. There is an emergency call button and phone in the cabins too.