Loiter time on orbit of Dragon

I see they are bringing Dragon down quite quickly compared to other cargo
delivery craft, and I wondered if this was just due to it being an early
test flight, or whether there is an issue over prolonged time on orbit.

Brian

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"Brian Gaff" writes:

I see they are bringing Dragon down quite quickly compared to other cargo
delivery craft, and I wondered if this was just due to it being an early
test flight, or whether there is an issue over prolonged time on orbit.

Sane thing to do with a craft that never was in orbit for longer than a
few hours before. Dragon has lots of hypergolic fuels on board, lots of
valves and plumbing... You certainly don't want it do develop a leak
somewhere or a connector corroding while docked to the ISS.

Getting it down as soon as it has done its job at the ISS and going over it
with a fine comb afterwards is just sensible I'd say.


Jochem

--
"A designer knows he has arrived at perfection not when there is no
longer anything to add, but when there is no longer anything to take away."
- Antoine de Saint-Exupery

In article , says...

"Brian Gaff" writes:

I see they are bringing Dragon down quite quickly compared to other cargo
delivery craft, and I wondered if this was just due to it being an early
test flight, or whether there is an issue over prolonged time on orbit.

Sane thing to do with a craft that never was in orbit for longer than a
few hours before. Dragon has lots of hypergolic fuels on board, lots of
valves and plumbing... You certainly don't want it do develop a leak
somewhere or a connector corroding while docked to the ISS.

Getting it down as soon as it has done its job at the ISS and going over it
with a fine comb afterwards is just sensible I'd say.

Agreed. It's still a very early test flight by a company that many see
as inexperienced. Best to bring it back soon to minimize the chance of
failure and maintain the forward momentum of the program. Later flights
can expand the flight envelope.

Jeff
--
" Ares 1 is a prime example of the fact that NASA just can't get it
up anymore... and when they can, it doesn't stay up long. "
- tinker

Jeff Findley explained on 5/30/2012 :
In article , says...

"Brian Gaff" writes:

I see they are bringing Dragon down quite quickly compared to other cargo
delivery craft, and I wondered if this was just due to it being an early
test flight, or whether there is an issue over prolonged time on orbit.

Sane thing to do with a craft that never was in orbit for longer than a
few hours before. Dragon has lots of hypergolic fuels on board, lots of
valves and plumbing... You certainly don't want it do develop a leak
somewhere or a connector corroding while docked to the ISS.

Getting it down as soon as it has done its job at the ISS and going over it
with a fine comb afterwards is just sensible I'd say.

Agreed. It's still a very early test flight by a company that many see
as inexperienced. Best to bring it back soon to minimize the chance of
failure and maintain the forward momentum of the program. Later flights
can expand the flight envelope.

Recall that because of the maneuvers in the "distant proximity" phase
of the tests, fuel on this flight is already constrained (hence the
tight launch window). Loitering in free flight may use up too much of
the reserves.

/dps


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Who, me? And what lacuna?

Brian Gaff presented the following explanation :
I see they are bringing Dragon down quite quickly compared to other cargo
delivery craft, and I wondered if this was just due to it being an early test
flight, or whether there is an issue over prolonged time on orbit.

And it's down (as AE noted in the STS group).

From Spaceflight Now:

quote
THURSDAY, MAY 31, 2012
1549 GMT (11:49 a.m. EDT)
SpaceX founder and chief designer Elon Musk just tweeted: "Splashdown
successful!! Sending fast boat to Dragon lat/long provided by P3
tracking planes."

The recovery team includes a 185-foot barge, an 80-foot crew boat, and
two 25-foot fast boats for dispatch to the capsule when it splashes
down.
/quote

and
quote
THURSDAY, MAY 31, 2012
1820 GMT (2:20 p.m. EDT)
Speaking with reporters from SpaceX headquarters in California, Elon
Musk says recovery crews are in the process of attaching cables to the
Dragon spacecraft to hoist it on the deck of a ship for the trip back
to port.

Dragon's re-entry and splashdown were very accurate, he said.

"It appears as though we were really hitting the bullseye in accuracy,
perhaps less than a mile," Musk said.

"In baseball terminology, this would be a grand slam," Musk said. "This
was bigger success than we had a reasonable right to expect."
/quote
(P3/submarine jokes elided)
http://spaceflightnow.com/falcon9/003/status.html

/dps

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