One of the problems surrounding the development of in-atmosphere hypersonic travel is communication. Specifically, when a vehicle gets up to hypersonic speeds, the atmosphere around it develops a variety of weird characteristics that includes (for starters) crazy heat, gas ionization or dissociation, and unusual airflow. The end result is a glowing mass of superfast air that is really quite difficult to get an optical signal through.
Optical signals (read: radio and laser) are essential for communication between the vehicle and bystanders, and communication is essential for testing, safety, and tactical reasons. So, we need a new way to communicate with hypersonic vehicles in-flight. I have some crazy ideas.
- One-way communication from the vehicle to outsiders by changing the characteristics of the extravehicular atmosphere.
- Inject some sort of material into the extravehicular space that alters the temperature/airflow profile. For example, a modulated cool liquid spray.
- Adjust the shape-profile of the vehicle itself. Moving components like flaps or somesuch could be incorporated. This would change the airflow pattern around the vehicle, which could be observed from the outside.
- Speed modulation. Presuming high accuracy of vehicle position tracking, modulate the vehicle speed to deliver information from onboard to onlookers.
- Dumping differing amounts and types of trace chemicals behind the vehicle. Perhaps injected into the exhaust stream. Presumes high accuracy and rapidity of exhaust stream chemical analysis by bystanders.
- Eject a tethered probe in the opposite direction of vehicle travel, hopefully outside of the immediate cloud of high-temperature craziness. Use optical transfer methods for the brief window of time before the interference builds up. Winch the probe back in, cool, and re-eject periodically. May require multiple probes.
- Develop some sort of quantum supercomputer that can model the turbulent airflow in real-time and take advantage of transient shifts in extravehicular space characteristics to choose optimal opportunities to beam out information with high-powered customized-waveform laser pulses. More than a little crazy, more than a little facetious.
- One-way communication from the outside to the vehicle by at-distance changing of the extravehicular space characteristics.
- Focused arrays of satellite laser beams track the vehicle. Amplitude modulation of the beams produces variable heating of certain key portions the extravehicular atmosphere. Temperature variations sensed by the vehicle and decoded. Very high-power, low-signal approach.
