NASA’s SpaceX Demo-2 Test Flight: Space
Station Departure and Splashdown Criteria
NASA and SpaceX are capable of supporting
seven splashdown sites off the coast of Florida
for the return of NASA’s SpaceX Demo-2 test
flight with NASA astronauts Robert Behnken
and Douglas Hurley from the International
Space Station as part the agency’s Commercial
Crew Program.
About two days prior to return, NASA and
SpaceX teams will select primary and alternate
splashdown target locations from the seven
possible sites, with additional decision milestones
about where Crew Dragon will splashdown
taking place prior to the astronauts boarding the
spacecraft, during free flight and before Crew
Dragon performs a deorbit burn.
Teams will evaluate the forecasted weather
conditions at the primary and alternate
splashdown sites at each milestone to determine
if the sites are “GO” or “NO-GO” for splashdown
and recovery.
The seven potential splashdown sites for Demo2 are: Pensacola, Tampa, Tallahassee, Panama
City, Cape Canaveral, Daytona and Jacksonville.

Approximate Locations
Selecting the Return Location
Splashdown locations are selected using
defined priorities starting with selecting a station
departure date and time with the maximum
number of return opportunities in geographically
diverse locations to protect for weather changes.
Teams also prioritize locations which require the
shortest amount of time between undocking
and splashdown based on orbital mechanics,
and splashdown opportunities that occur in
daylight hours.

Crew Dragon has the capability to execute a
unique series of orbit-lowering maneuvers using
its Draco thrusters to line up its ground track for
each primary location and maintain the capability
to change to alternate sites in free-flight as
weather constraints dictate.
Return Decision Milestones
Pre-Departure (1 to 2 days prior to
approximate departure)
SpaceX and NASA will jointly make the decision
to depart 48 hours prior to splashdown based
on the status of the primary and alternate
splashdown sites.
6 hours before undocking
NASA and SpaceX make a decision on primary
splashdown target.

NASAfacts

National Aeronautics and Space Administration

 5 hours before Deorbit (6 hours before Splashdown)
If conditions at the splashdown site are marginal and
exceed the accepted criteria, SpaceX and NASA will jointly
make a decision about whether to proceed with deorbit.
Crew Dragon Claw Separation (1 hour, 20 minutes
before Splashdown)
SpaceX will monitor changes to conditions through the
decision to proceed with the deorbit burn (30 minutes
before claw separation prep), when a final determination
to proceed with deorbit will be made. The claw is located
on Crew Dragon’s trunk, connecting thermal control,
power, and avionics system components located on the
trunk to the capsule.
Recovery Criteria
The weather criteria for recovery for this demonstration
mission is as follows.
2.5 hours before undocking
SpaceX will monitor changes to conditions until 2.5 hours
prior to the scheduled undocking, when a determination
to proceed with departure will be made. If conditions
are marginal and exceed the accepted criteria, a joint
recommendation by SpaceX and NASA will be made
whether to proceed with undocking.
Undocking
NASA and SpaceX will make the final decision to proceed
after the astronauts are ready inside Crew Dragon just
before undocking.
Free Flight
Crew Dragon will proceed with departure phasing burns
as planned even if conditions are marginal or NO-GO at
any upcoming supported landing site and exceed the
accepted criteria. Given the splashdown site may be
24 hours or more away and weather can change, Crew
Dragon will always proceed with departure phase burns
to preserve the supported splashdown opportunity.
Wave-off
If conditions remain NO-GO at the supported splashdown
site, SpaceX and NASA will jointly make a decision to
“wave-off.” In a wave-off scenario, Crew Dragon will remain
in orbit for the next landing attempt 24-48 hours later.

National Aeronautics and Space Administration
Lyndon B. Johnson Space Center
Houston, Texas 77058
www.nasa.gov
FS-2020-07-002-JSC

 • Wind Speed: No greater than 15 ft/sec
  •  Wave Period & Significant Wave Height: Driven
by wave height and wave period relationship; in
general, when wave height and wave period are
the same, the condition is no-go. No greater than 7
degrees wave slope.
 •  Rain: < 25% probability of 25 dBz in protected boundary
 •  Lightning: No less than 10 miles and no greater than
25% probability of lightning in protected boundary
  •  Helicopter Start & Hover Test: Pass-Fail test to
confirm operational capability
  •  Helicopter Operational Limits: Vessel limits will
apply on motion (pitch, roll), cloud visibility, cloud
ceiling and lightning
   - Vessel Pitch, Roll: No greater than 4 degrees
   - Ceiling: No less than 500 feet
   -  Visibility: No less than ½ mile for day and 1 mile
for night