station and in the allowed flight region – unless it can communicate via satellite).
The payload may be rolled out to the launch area several times before the surface
and upper atmosphere conditions prove acceptable for launch.
4.2.5 Command & Control
In many cases there is no attempt to control the trajectory of the balloon, as the
intention is simply to fly the projected winds. For example, a balloon launched
from McMurdo will naturally be controlled by the polar vortex circulating over
Antarctica. These are LDB missions with science payloads. This is also true of a
flight from Kiruna, Sweden that will be subject to the easterly winds that carry it
to Canada.
Section 3.4.2 discussed the command and control capabilities of the OCC and
ROCC. As long as a balloon is in line of sight, the ROCC is able to provide the
science team with telemetry from their experiments and, if necessary command
termination of the flight.
Flight Trajectory Control
The potential for flight trajectory control is an enabling technology for long
SPB flights. Unlike a balloon that floats with the prevailing winds for the duration of its flight, the purpose of trajectory control is to slightly modify the balloon flight track over time in order to be able to steer the system to preferred
flight latitudes. This would allow a balloon to be launched from one location
and then be shifted to a latitude band where there will be little population or
land beneath during the mission. Toward the end of the mission, the balloon
would be steered back to a desired location to safely terminate the flight and
recover the science instrument.
Commercial Balloon Trajectory Control
Chapter 5 discusses trajectory control for commercial balloon flights. The most
experienced company with this ability is Loon, LLC. The overall goal of Project
Loon is to provide worldwide internet coverage using a network of long-duration
SPBs. Since 2013, Loon has launched over 1,600 balloons from multiple tropical
and middle latitude locations.
Project Loon uses software algorithms to determine where its balloons
require to go, and by exploiting the different wind directions at different altitudes they steer the balloons by rising or descending them to an altitude where
winds move in the desired direction. By moving with the wind, the balloons can
be arranged to form a single large communications network. Each one can provide connectivity for a ground area about 40 km (64 mi) in diameter at rates
4.2 Mission Operations 75
The payload may be rolled out to the launch area several times before the surface
and upper atmosphere conditions prove acceptable for launch.
4.2.5 Command & Control
In many cases there is no attempt to control the trajectory of the balloon, as the
intention is simply to fly the projected winds. For example, a balloon launched
from McMurdo will naturally be controlled by the polar vortex circulating over
Antarctica. These are LDB missions with science payloads. This is also true of a
flight from Kiruna, Sweden that will be subject to the easterly winds that carry it
to Canada.
Section 3.4.2 discussed the command and control capabilities of the OCC and
ROCC. As long as a balloon is in line of sight, the ROCC is able to provide the
science team with telemetry from their experiments and, if necessary command
termination of the flight.
Flight Trajectory Control
The potential for flight trajectory control is an enabling technology for long
SPB flights. Unlike a balloon that floats with the prevailing winds for the duration of its flight, the purpose of trajectory control is to slightly modify the balloon flight track over time in order to be able to steer the system to preferred
flight latitudes. This would allow a balloon to be launched from one location
and then be shifted to a latitude band where there will be little population or
land beneath during the mission. Toward the end of the mission, the balloon
would be steered back to a desired location to safely terminate the flight and
recover the science instrument.
Commercial Balloon Trajectory Control
Chapter 5 discusses trajectory control for commercial balloon flights. The most
experienced company with this ability is Loon, LLC. The overall goal of Project
Loon is to provide worldwide internet coverage using a network of long-duration
SPBs. Since 2013, Loon has launched over 1,600 balloons from multiple tropical
and middle latitude locations.
Project Loon uses software algorithms to determine where its balloons
require to go, and by exploiting the different wind directions at different altitudes they steer the balloons by rising or descending them to an altitude where
winds move in the desired direction. By moving with the wind, the balloons can
be arranged to form a single large communications network. Each one can provide connectivity for a ground area about 40 km (64 mi) in diameter at rates
4.2 Mission Operations 75