A trade-off with cable-supported rail tracks is the fact that in special conditions, the cable-supported rail has to be transitioned into a firm, elevated fixed rail. In case of the Aerobus design, this is a vertically positioned I-beam in each direction, supported by steel columns and presenting to the vehicle bogies (trucks and wheels) cross-sections identical to the cable-supported rail. Firm, elevated fixed rails are required under the following circumstances:

(A) Tight Turns

The Aerobus vehicle is designed to contain multiple modules of approximately 8 ft H x 9ft W x 11 ft L dimensions, these are assembled into multiple-module vehicles by the aid of articulation joints and bogies between adjacent modules. (Vehicles of 3 to 12 modules to accommodate various capacities can be provided). Utilizing firm, elevated fixed rail, turns of a minimum 80 ft radius. can be accommodated. Speed reduction in these curves is generally proportional to the tightness of the curve. These transitions are hardly noticeable to the passengers.

Normally, when a cable-to-fixed rail transition occurs to make a turn, the cables leading to both ends of the turn must be terminated and anchored in a reinforced ground anchor.

(B) Stations

A transition from cable supported rails to firm, elevated fixed rails must be made prior to entering a station. Similarly, a reverse transition from fixed rail to cable-supported rail is made after leaving a station. This requirement provides added dimensional stability for minimal clearance prior to entering the stations with platforms aligned lengthwise with the vehicles; this also facilities alignment of platform doors for automatic, simultaneous opening, if desired for passenger protection.

Note, that in these cases, none of the transitions require the termination of any of the cables, as the cables normally supporting the rails are simply placed underneath the elevated fixed rails; and, therefore, remain continuous until the transition back to cable-supported rail on the other side of the station. The suspension cables may continue above the station, or the station structure may support a pylon above it, depending on the location.

(C) Pylons

The Pylons support the Suspension Cables as the Suspension Cable is laid into the top saddle with some freedom of movement on rollers.

Conversely, the lower saddles on the pylons are fundamentally a short segment of a fixed rail to hold down the cables which support the rails between pylons. The rail supporting cables are pre-loaded by the vertical hanger cables, which in the absence of a vehicle, keep the cable supported rail in an arch above the horizontal. The rail supporting cables remain uninterrupted at the saddles as they are placed underneath the fixed rail segment similarly to the manner described at the stations. The vehicles make a smooth transition through the tapered ends of these short segments of fixed rail on each side. The short fixed rail segments are pivoted at the center to adjust to asymmetrical loading, as when there is a vehicle on one side of the pylon and none on the other.

(D) Switches

All Aerobus switches are fixed rail segments, moving and locking into alternative positions under controls. Switches normally require discontinuation of the cable-supported rail and transition to firm, elevated fixed rail; and therefore, it is highly practical to combine them at the location of fixed rail turns, or entry/exits of stations.

Aerobus, as all elevated transit, has an operating limitation in very high wind conditions. It is to be noted that mostly because of this consideration, another improvement was made to the bogie and wheel design. In the production vehicle, each module is driven by four powered wheels (two on each end of the module as part of a four-wheel bogie over the articulation joint). Associated with each vertical driven wheel is a horizontal guide-wheel bogie over the articulation joint). Associated with each vertical driven wheel is also a horizontal guide-wheel on the outside of the rail, thus locking each bogie at two positions on each side firmly onto the two rails of the track. The vehicle is most sensitive to crosswinds, since it presents the largest surface to these forces. In Aerobus, four measures compensate against high winds: (1) the cable-supported track is flexible to allow sway in the suspended vehicle locked into the track, (2) the secondary suspension of the vehicle also permits sway, (3) the vehicle sides are mildly curved to lessen the wind-resistance presented, and (4) Aerobus has certain proprietary approaches which it intends to evaluate to increase vehicle stability and wind resistance. Until such evaluation, we have chosen to limit normal operations to wind speeds of 45 miles per hour until passenger comfort studies can certify normal operations in winds above 45 miles per hour. Note: the Roosevelt Island cable-car in New York City is shut down when wind speeds reach 45 miles per hour.