Safety also applies to potential interference with air traffic and populations at
the landing and recovery site. The range user performs a functional test of the balloon termination and recovery system prior to launch to certify the flight safety
system.
NASA claims that in over 2,300 scientific balloon flights, there has never been
a single injury to a crew member or anyone else.
4.2.3 Real-Time weather and winds
Pre-Launch Day Forecasting
While the scientists and launch team make their final preparations to initiate a
mission, meteorologists compile data for daily weather briefings. Using all the
resources available to them (see above) they run computer models to identify a
launch window for the following day and for about three days out, then make a
recommendation. The Campaign Manager has the final decision on whether to
attempt a launch the following day.
An ascent and float trajectory forecast is also produced and issued to the Safety
Manager for a Go/No-Go recommendation. The final Go/No-Go comes after an
analysis of the latest trajectory forecast on the morning of the launch.
The wind constraints and criteria can vary significantly with the type and size
of the balloon, but typically include:
• Surface winds less than 7 kts.
• Low-level winds to the top of the balloon less than 12 kts.
• Surface and low-level winds in a stable and uniform direction.
• No precipitation at the launch site, and no thunderstorms within 50 nmi.
• Launch operations can be hindered by thick fog and/or very low clouds.
Ascent & Float Trajectory Forecast
CSBF Meteorology uses a combination of legacy FORTRAN programs that date
to the 1970’s along with UNIX scripts and complicated Excel macros to produce
ascent, float, and descent trajectory predictions in text and KML format. The raw
data for each of these is obtained from model data wind forecasts in a text format
using a UNIX script and GEMPAK, an analysis, display, and product generation
package for meteorological data.
The meteorologists have the option of adjusting the model data wind forecasts
manually using SINBAD, a software library for Java, Python, and Racket that
makes it very easy to uniformly access online data sources presented in standard
formats. This is used to make pre-flight ascent rate predictions as well as zeropressure balloon altitude projections
72 Mission Drivers and Operations
the landing and recovery site. The range user performs a functional test of the balloon termination and recovery system prior to launch to certify the flight safety
system.
NASA claims that in over 2,300 scientific balloon flights, there has never been
a single injury to a crew member or anyone else.
4.2.3 Real-Time weather and winds
Pre-Launch Day Forecasting
While the scientists and launch team make their final preparations to initiate a
mission, meteorologists compile data for daily weather briefings. Using all the
resources available to them (see above) they run computer models to identify a
launch window for the following day and for about three days out, then make a
recommendation. The Campaign Manager has the final decision on whether to
attempt a launch the following day.
An ascent and float trajectory forecast is also produced and issued to the Safety
Manager for a Go/No-Go recommendation. The final Go/No-Go comes after an
analysis of the latest trajectory forecast on the morning of the launch.
The wind constraints and criteria can vary significantly with the type and size
of the balloon, but typically include:
• Surface winds less than 7 kts.
• Low-level winds to the top of the balloon less than 12 kts.
• Surface and low-level winds in a stable and uniform direction.
• No precipitation at the launch site, and no thunderstorms within 50 nmi.
• Launch operations can be hindered by thick fog and/or very low clouds.
Ascent & Float Trajectory Forecast
CSBF Meteorology uses a combination of legacy FORTRAN programs that date
to the 1970’s along with UNIX scripts and complicated Excel macros to produce
ascent, float, and descent trajectory predictions in text and KML format. The raw
data for each of these is obtained from model data wind forecasts in a text format
using a UNIX script and GEMPAK, an analysis, display, and product generation
package for meteorological data.
The meteorologists have the option of adjusting the model data wind forecasts
manually using SINBAD, a software library for Java, Python, and Racket that
makes it very easy to uniformly access online data sources presented in standard
formats. This is used to make pre-flight ascent rate predictions as well as zeropressure balloon altitude projections
72 Mission Drivers and Operations