NSBF Palestine, TX
In June 5, 1989, a ZPB was launched from Palestine, TX. The flight developed
without troubles, but in the final stage the balloon passed over a thunderstorm west
of Fort Worth. For some unknown reasons (at the time) an uncommanded release
of the payload occurred along with the separation of the parachute from the gondola, which fell freely from an altitude of 37 km (120,000 ft) and struck the ground
two minutes later at an estimated speed of 1,127 km/h (700 mph). It came down
on a farm located four or five miles outside Graham in north central Texas. This
harrowing story is included in Appendix 3.
There have been hundreds of flights in the U.S. where the balloons and payloads were recovered successfully. It is more informative to give the reader a sense
of what a difficult recovery entails, so here are a few examples.
Antarctica Recovery Operations
A ground team has the advantage that the polar vortex winds will likely keep the
balloon over the continent, enabling them to pick the time of termination to have
the recovery operation occur within a reasonable distance.
While McMurdo Station is on the coast at an elevation of 33 ft, Antarctica is the
highest continent on Earth with an average elevation of 2,500 m (8,200 ft). The
elevation at the South Pole is 2,835 m (9,300 ft). The highest point on the icecap
is in the Australian Antarctic Territory at 4,100 m (13,451 ft). Mount Vinson in the
Chilean claimed portion of the continent is the highest mountain at 4,892 m
(16,050 ft). It is therefore desirable to recover a payload in the lower elevations for
the safety of the crew and aircraft.
If the altitude of the landing is high, the recovery crews require to wear oxygen
masks. The distance from the nearest base, and the condition of the terrain, are
additional factors to be considered. Sometimes an advance team is deployed by a
small plane several days before the actual recovery of the payload begins, simply
to prepare the terrain for the landing of the aircraft that will remove the payload
parts afterward. Also, it is often necessary to drop fuel caches along the route to
the site in order to cover the long distances across the ice.
Another complication arises if the balloon gondola was not developed with the
specific requirements for Antarctic recovery as a primary design constraint, in particular the need to break it down in the field, in the cold, and at a relatively high altitude. Recovery operations often occur in very bad weather, where the recovery team
may have only a limited time to work before they must abandon the site. Depending
on the altitude of the site, the physical capacity of recovery team members will be
limited. Given experience of the difficulty of performing recoveries on high ice plateaus, flight termination and recovery is now planned only at lower elevations.
Typically, aircraft ferry in the recovery team. A C-130 heavy-lift cargo aircraft can
land virtually anywhere within a large portion of the Antarctic landmass and recover
the largest balloon payloads intact, or after the minimum of disassembly in the field.
4.2 Mission Operations 77
In June 5, 1989, a ZPB was launched from Palestine, TX. The flight developed
without troubles, but in the final stage the balloon passed over a thunderstorm west
of Fort Worth. For some unknown reasons (at the time) an uncommanded release
of the payload occurred along with the separation of the parachute from the gondola, which fell freely from an altitude of 37 km (120,000 ft) and struck the ground
two minutes later at an estimated speed of 1,127 km/h (700 mph). It came down
on a farm located four or five miles outside Graham in north central Texas. This
harrowing story is included in Appendix 3.
There have been hundreds of flights in the U.S. where the balloons and payloads were recovered successfully. It is more informative to give the reader a sense
of what a difficult recovery entails, so here are a few examples.
Antarctica Recovery Operations
A ground team has the advantage that the polar vortex winds will likely keep the
balloon over the continent, enabling them to pick the time of termination to have
the recovery operation occur within a reasonable distance.
While McMurdo Station is on the coast at an elevation of 33 ft, Antarctica is the
highest continent on Earth with an average elevation of 2,500 m (8,200 ft). The
elevation at the South Pole is 2,835 m (9,300 ft). The highest point on the icecap
is in the Australian Antarctic Territory at 4,100 m (13,451 ft). Mount Vinson in the
Chilean claimed portion of the continent is the highest mountain at 4,892 m
(16,050 ft). It is therefore desirable to recover a payload in the lower elevations for
the safety of the crew and aircraft.
If the altitude of the landing is high, the recovery crews require to wear oxygen
masks. The distance from the nearest base, and the condition of the terrain, are
additional factors to be considered. Sometimes an advance team is deployed by a
small plane several days before the actual recovery of the payload begins, simply
to prepare the terrain for the landing of the aircraft that will remove the payload
parts afterward. Also, it is often necessary to drop fuel caches along the route to
the site in order to cover the long distances across the ice.
Another complication arises if the balloon gondola was not developed with the
specific requirements for Antarctic recovery as a primary design constraint, in particular the need to break it down in the field, in the cold, and at a relatively high altitude. Recovery operations often occur in very bad weather, where the recovery team
may have only a limited time to work before they must abandon the site. Depending
on the altitude of the site, the physical capacity of recovery team members will be
limited. Given experience of the difficulty of performing recoveries on high ice plateaus, flight termination and recovery is now planned only at lower elevations.
Typically, aircraft ferry in the recovery team. A C-130 heavy-lift cargo aircraft can
land virtually anywhere within a large portion of the Antarctic landmass and recover
the largest balloon payloads intact, or after the minimum of disassembly in the field.
4.2 Mission Operations 77