Successful flight by Blue Origin

I saw this on Twitter this morning.

Blue Origin - Historic Rocket Landing - Published on Nov 24, 2015
https://www.youtube.com/watch?v=9pillaOxGCo

Yes, I know it's only suborbital, but a successful launch, separation,
descent, and landing from 100 km is nothing to sneeze at.

Jeff
--
"the perennial claim that hypersonic airbreathing propulsion would
magically make space launch cheaper is nonsense -- LOX is much cheaper
than advanced airbreathing engines, and so are the tanks to put it in
and the extra thrust to carry it." - Henry Spencer

"Jeff Findley" wrote in message
...


I saw this on Twitter this morning.

Blue Origin - Historic Rocket Landing - Published on Nov 24, 2015
https://www.youtube.com/watch?v=9pillaOxGCo

Yes, I know it's only suborbital, but a successful launch, separation,
descent, and landing from 100 km is nothing to sneeze at.

Jeff

Yeah, one step at a time. I hope they make it, but even if they don't, them
more trying, the better our odds.

--
Greg D. Moore http://greenmountainsoftware.wordpress.com/
CEO QuiCR: Quick, Crowdsourced Responses. http://www.quicr.net

On 11/24/15 8:15 PM, JF Mezei wrote :
Question:


After MECO, they separate capsule from first stage. Does Capsule have
its own engine that brings it higher up or do both continue on inertia
to basically same altitude and start to drop down at roughly same time ?


Considering that the parachute landing of capsule seemed very rough, why
not keep capsule attached to first stage and have both land using
engines with a nice smooth landing ?

Or would that require too much fuel to slow down the capsule's mass ?

Could they use the capsule's parachute to slow down 1st stage+capsule
and then detach parachiute as engines start for the landing ?

I don't know but I would speculate that they think a vertical rocket
landing is too dangerous for a crew.


Alain Fournier

In article m,
says...

Elon Musk tweeted to congratulate them, but warned that suborbital was
orders of magnitudes easer than orbital.


However, from poimt of view of first stage, would Blue Origin be
submitted to the same difficulties as Falcon 9's first stage ?

Not really. Falcon 9's first stage surely has a much better mass
fraction (it certainly has higher delta-V requirement). Because of
this, Falcon 9's first stage can't hover because it is so light at
landing. Blue Origin's much smaller stage looks to have higher dry mass
(visually, based on the size, air brakes, landing gear, and etc.).

Or does Blue Origin's smaller size make it fare easier to bring back for
successfull landing ?

Size isn't the issue. The mass fraction and the thrust to weight ratio
makes a huge difference. You can see in the video that Blue Origin's
stage can hover. This is a huge advantage when landing.

Others have speculated that what SpaceX ought to do is outfit the Falcon
9 Full Thrust first stage with Super Draco engines for final approach
and landing. This would allow hover. But, it also increases complexity
and adds a significant amount of dry mass (since the Super Dracos use
different propellant, they need their own tanks, plumbing, and etc).

Jeff
--
"the perennial claim that hypersonic airbreathing propulsion would
magically make space launch cheaper is nonsense -- LOX is much cheaper
than advanced airbreathing engines, and so are the tanks to put it in
and the extra thrust to carry it." - Henry Spencer

In sci.space.policy message -
september.org, Wed, 25 Nov 2015 09:50:12, Jeff Findley
posted:

Others have speculated that what SpaceX ought to do is outfit the Falcon
9 Full Thrust first stage with Super Draco engines for final approach
and landing. This would allow hover. But, it also increases complexity
and adds a significant amount of dry mass (since the Super Dracos use
different propellant, they need their own tanks, plumbing, and etc).


Increasing the size of tanks adds relatively little weight.
SuperDracos are relightable, so if used at landing they might also be
used for extra boost at takeoff.

--
(c) John Stockton, Surrey, UK. Turnpike v6.05 MIME.
Merlyn Web Site - FAQish topics, acronyms, & links.

On 11/24/2015 9:01 PM, Alain Fournier wrote:
On 11/24/15 8:15 PM, JF Mezei wrote :
Question:


After MECO, they separate capsule from first stage. Does Capsule have
its own engine that brings it higher up or do both continue on inertia
to basically same altitude and start to drop down at roughly same time ?


From what I've seen I believe it is the latter. The separation kick
gives them the separation they need on return.


Considering that the parachute landing of capsule seemed very rough, why
not keep capsule attached to first stage and have both land using
engines with a nice smooth landing ?

Or would that require too much fuel to slow down the capsule's mass ?

Could they use the capsule's parachute to slow down 1st stage+capsule
and then detach parachiute as engines start for the landing ?

I don't know but I would speculate that they think a vertical rocket
landing is too dangerous for a crew.


Alain Fournier


Agree video shows a pretty rough capsule landing. I think there must be
a plan for augmentation of this. Speculation would be some kind of kick
thruster that fires just before landing ala Soyuz or maybe a deployable
air bag? I think the focus of this test was primarily elsewhere as in...

The booster (New Shepard) comes in very fast (hot). I suspect this is by
design to overcome cross winds, turbulence etc. in the atmosphere. The
fins and vanes used for control are fairly small and probably need the
speed to operate effectively. The engine fires at just under 10kft and
builds thrust but only rapidly below 1kft. Somewhere between 500-100
feet I suspect the G loading is tremendous. Even if only for a very
short period of time probably NOT something an amateur crew of space
touristas would want to experience. And I agree I don't think you want
all that potential explosive UNDERNEATH you when landing. So I highly
doubt that a crewed New Shepard upon landing is in the cards, ever.
Otherwise why go to all the trouble of making them separable in the
first place?

But all-in-all a great achievement. Hats off the the Blue Origin team on
accomplishing this historic first milestone*.

Dave

*Landing a booster intact from "space", i.e. above 300kft. Yes the
booster followed the capsule high enough to have considered to have
crossed that somewhat imaginary boundary from what I've read...

**SpaceX must be peeved that BO snatched this "first" from them!
Ahh competition. Soul food!

***Yes Elon is right, there is a big difference between a sub-orbital vs
orbital rocket. Problem is, Falcon 9 first stage is not orbital either.
Until there is a SSTO rocket, the BO record will stand, heh heh...

****SpaceX can still set the record for a first liquid rocket booster to
be recovered from space in reusable condition at sea! (lots of asterisks
there...)

*****Interesting that BO got the FAA ok to do this test from Van Horn
Tx! How/why was BO allowed a fast track here? Was this a first attempt
or just all previous attempts when unpublicized? Considering all the
machinations SpaceX has done through. Grasshopper - F9R-Dev1 - WSNM -
at sea landing attempts - to someday LC-13 at Canaveral. SpaceX could
have had this record perhaps a year or more earlier if they had pursued
a WSNM F9R-Dev2, or not attempted a known (possibly-actually)
destructive F9R-Dev1 test and taken that rocket to WSNM right away? Ahh,
barn doors & horses and the road not taken....

In article m,
says...

Elon Musk tweeted to congratulate them, but warned that suborbital was
orders of magnitudes easer than orbital.


However, from poimt of view of first stage, would Blue Origin be
submitted to the same difficulties as Falcon 9's first stage ?

Or does Blue Origin's smaller size make it fare easier to bring back for
successfull landing ?

Saw this reference on the ARocket email list. This article about one of
the SpaceX first stage landing attempts gives a lot of technical details
which illustrate that it goes both higher and much faster than Blue
Origin's suborbital stage.

http://www.spaceflight101.net/video-...ds-leading-to-
falcon-9-booster-crash-landing.html

From above:
"the 43-meter long first stage started out on its journey immediately
after stage separation - firing its thrusters to maneuver out of the
exhaust of the second stage and re-orient to an engines-forward posture
for the first of three propulsive maneuvers - starting out at an
altitude of close to 80 Kilometers and a speed of over 2 Kilometers per
second at separation"

And:
"the booster successfully ignited three of its Merlin 1D engines at
around T+4 minutes & 30 seconds - each delivering up to 66,700 Kilogram-
force of thrust. This retrograde boost-back burn aimed to reduce the
downrange travel distance of the first stage by about 50%, compared with
a fully ballistic path not including any maneuvers after separation. The
boost back burn also modified the exospheric trajectory of the stage,
pushing the apogee below 125 Kilometers."

Jeff
--
"the perennial claim that hypersonic airbreathing propulsion would
magically make space launch cheaper is nonsense -- LOX is much cheaper
than advanced airbreathing engines, and so are the tanks to put it in
and the extra thrust to carry it." - Henry Spencer

In article id,
lid says...

In sci.space.policy message -
september.org, Wed, 25 Nov 2015 09:50:12, Jeff Findley
posted:

Others have speculated that what SpaceX ought to do is outfit the Falcon
9 Full Thrust first stage with Super Draco engines for final approach
and landing. This would allow hover. But, it also increases complexity
and adds a significant amount of dry mass (since the Super Dracos use
different propellant, they need their own tanks, plumbing, and etc).


Increasing the size of tanks adds relatively little weight.

Which is the approach of the existing design. The center engine us used
for both launch and landing and uses the same tanks as the rest of the
engines.

SuperDracos are relightable, so if used at landing they might also be
used for extra boost at takeoff.

Possibly, but you'd still need separate tanks, separate plumbing, and
etc. This is because the SuperDracos use toxic hypergolic fuel and
oxidizer, unlike the Merlin engines which use LOX/kerosene. All that
extra equipment adds both complexity and mass.

That and using the SuperDracos at liftoff would be both inefficient and
introduce more risk during launch. SpaceX's philosophy is to not
endanger the primary mission when adding landing capability to the first
stage. Firing SuperDracos during launch runs precisely counter to this
philosophy. In other words, I don't think Musk would approve of this.

Jeff
--
"the perennial claim that hypersonic airbreathing propulsion would
magically make space launch cheaper is nonsense -- LOX is much cheaper
than advanced airbreathing engines, and so are the tanks to put it in
and the extra thrust to carry it." - Henry Spencer

On Saturday, November 28, 2015 at 12:31:55 AM UTC-5, JF Mezei wrote:
Would their use even be permitted for near ground operations ?
(considering how toxic hypergolics are).

Yes since this is the means for propulsive landing of the Dragon V2 reusable capsule! Wherein the SuperDraco engines, their tankage AND propellant are all part of the crewed capsule!

Dave

In article om,
says...

On 2015-11-30 14:17, David Spain wrote:

Yes since this is the means for propulsive landing of the Dragon V2 reusable capsule! Wherein the SuperDraco engines, their tankage AND propellant are all part of the crewed capsule!



Does the use of hypergolics (as in the case for Soyuz) for the landing
require that the whole area is clear of humans ?

Soyuz is different. They use H2O2 with a catalyst for reaction control
and they use solids triggered by a radioactive source/detector to
cushion the final landing (since landing with the parachutes alone is
survivable, but can cause injuries).

I guess for a 1st stage, humans stay clear anyways due to risk of a big
explosion.

Not really, the tanks are mostly empty by then. Yes, there is fire
during a crash, but it's not that bad (as evidenced by the minor damage
done to the landing barge during the so far unsuccessful landing
attempts.

And for a capsule in parachute, landing precision is very low so by the
time crews get to it, any fumes have been blown away.

I don't know what this means. But, inhalation of toxic fumes, during
descent via parachute, from a leaky RCS was a problem on at least one
Apollo flight.

I recall for the shuttle, they spent quite some time with humans staying
away from the just landed orbiter in case there were fumes. (and APU
still running on hypergolics).

NASA is also quite cautious under normal circumstances. In an
emergency, the already suited up fire crew would no doubt "go in"
despite the risk.

Jeff
--
"the perennial claim that hypersonic airbreathing propulsion would
magically make space launch cheaper is nonsense -- LOX is much cheaper
than advanced airbreathing engines, and so are the tanks to put it in
and the extra thrust to carry it." - Henry Spencer