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SpaceX Falcon Heavy Flight Animation
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Jeff Findley
Jan 28, 2015, 6:10:04 AM1/28/15
to
SpaceX - Falcon Heavy - Flight Animation
https://www.youtube.com/watch?v=4Ca6x4QbpoM
From the video description:
Published on Jan 27, 2015
When Falcon Heavy lifts off later this year, it will be the
most powerful operational rocket in the world by a factor
of two. Thrust at liftoff is equal to approximately eighteen
747 aircraft operating simultaneously.
The one thing I doubt we'll see in the test launch is all three of the
first stage cores landing at the launch site. As far as I know, SpaceX
does not yet have permission to land a core at The Cape. I'd imagine
permission to land three (two almost simultaneously) in relatively close
proximity will take an additional level of permission beyond that.
This video is surely to show the future direction. In other words,
before ULA officially announces details of their "next generation"
launch vehicle, SpaceX is repeating what they plan to do with Falcon
Heavy. If Falcon Heavy can demonstrate fly-back and landing of three of
four Falcon Heavy first stages before ULA starts flying their "next
generation" system, the learner will truly be the new master.
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
William Mook
Jan 28, 2015, 8:38:16 AM1/28/15
to
William Mook
Jan 28, 2015, 8:53:54 AM1/28/15
to
On Thursday, January 29, 2015 at 12:10:04 AM UTC+13, Jeff Findley wrote:
Not a lot of details how thermal protection is achieved during re-entry. Thermal loads for the booster rockets aren't as great as for the orbital booster but the attitude during re-entry, if accurate must use some sort of thermal protection on the engine - or the engine itself somehow, assuming the animation accurate.
Let's assume its accurate for a second. Thermal protection must use a gas generation cycle to create a stagnation zone well ahead of the exit plane. That would be technically sweet.
The only quibble I have is the massive landing gear. Its a point of failure and very massive as well. Unless you're planning to land on an unprepared surface, it really makes no sense to haul those things around. They're landing on the X - which is no larger than an elevator shaft - so they really should have an active transporter there that catches the falling rocket at that location. The technology to do this is well-advanced, and the savings are well worth the effort.
https://www.youtube.com/watch?v=R6pPwP3s7s4
I wonder what the mass break down is for the landing gear? I would wager it doubles the inert weight of the whole system. An oversized gripper that grasped the mounting brackets for the landing gear would allow dispensing with the rest of the landing gear. It would also improve aerodynamics at a critical time.
This could be tested with a sub-scale rocket system, and then tried on the larger system.
Rick Jones
Jan 29, 2015, 8:05:46 AM1/29/15
to
Jeff Findley <jfin...@cinci.nospam.rr.com> wrote:
> The one thing I doubt we'll see in the test launch is all three of
> the first stage cores landing at the launch site. As far as I know,
> SpaceX does not yet have permission to land a core at The Cape. I'd
> imagine permission to land three (two almost simultaneously) in
> relatively close proximity will take an additional level of
> permission beyond that.
Heck, I doubt we'll see even one landing at the launch site. On the
> The one thing I doubt we'll see in the test launch is all three of
> the first stage cores landing at the launch site. As far as I know,
> SpaceX does not yet have permission to land a core at The Cape. I'd
> imagine permission to land three (two almost simultaneously) in
> relatively close proximity will take an additional level of
> permission beyond that.
barge at sea, sure. The luddite in me would even wonder if there
would be any first stage landing attempt on the first Falcon Heavy
launch in the first place. Particularly if the first launch intends
to demonstrate to the USAF/NRO/et al the maximum mass-to-orbit
capabilities.
From http://en.wikipedia.org/wiki/Falcon_Heavy
SpaceX has indicated that the Falcon Heavy payload performance to
geosynchronous transfer orbit (GTO) will be reduced by addition of
the reusable technology, but would fly at much lower launch
price. With full reusability on all three booster cores, GTO
payload will be 7,000 kg (15,000 lb). If only the two outside
cores fly as reusable cores while the center core is expendable,
GTO payload would be approximately 14,000 kg (31,000 lb).[34]
"Falcon 9 will do satellites up to roughly 3.5 tonnes, with full
reusability of the boost stage, and Falcon Heavy will do
satellites up to 7 tonnes with full reusability of the all three
boost stages," [Musk] said, referring to the three Falcon 9
booster cores that will comprise the Falcon Heavy's first
stage. He also said Falcon Heavy could double its payload
performance to GTO "if, for example, we went expendable on the
center core."
If the specs in the box on the right of that page are accurate, going
fully expendable means 21,200 kg to GTO.
rick jones
--
portable adj, code that compiles under more than one compiler
these opinions are mine, all mine; HP might not want them anyway... :)
feel free to post, OR email to rick.jones2 in hp.com but NOT BOTH...
David Spain
Feb 3, 2015, 3:23:56 PM2/3/15
to
On Wednesday, January 28, 2015 at 6:10:04 AM UTC-5, Jeff Findley wrote:
> SpaceX - Falcon Heavy - Flight Animation
> https://www.youtube.com/watch?v=4Ca6x4QbpoM
>
> From the video description:
> Published on Jan 27, 2015
> When Falcon Heavy lifts off later this year, it will be the
> most powerful operational rocket in the world by a factor
> of two. Thrust at liftoff is equal to approximately eighteen
> 747 aircraft operating simultaneously.
>
> The one thing I doubt we'll see in the test launch is all three of the
> first stage cores landing at the launch site. As far as I know, SpaceX
> does not yet have permission to land a core at The Cape. I'd imagine
> permission to land three (two almost simultaneously) in relatively close
> proximity will take an additional level of permission beyond that.
>
For some reason I thought this video was supposed to be from Vandenberg. Maybe I didn't read the caption too carefully. But isn't the first F9H flight to be from Vandenberg?
> SpaceX - Falcon Heavy - Flight Animation
> https://www.youtube.com/watch?v=4Ca6x4QbpoM
>
> From the video description:
> Published on Jan 27, 2015
> When Falcon Heavy lifts off later this year, it will be the
> most powerful operational rocket in the world by a factor
> of two. Thrust at liftoff is equal to approximately eighteen
> 747 aircraft operating simultaneously.
>
> The one thing I doubt we'll see in the test launch is all three of the
> first stage cores landing at the launch site. As far as I know, SpaceX
> does not yet have permission to land a core at The Cape. I'd imagine
> permission to land three (two almost simultaneously) in relatively close
> proximity will take an additional level of permission beyond that.
>
I didn't hear as to whether the inaugural flight of the F9H would attempt booster recovery. I suppose it could, but I would think that the KISS principle would defer that attempt for later. Plus they have no landing sites on the West Coast yet AFAIK. Neither any of those islands off the coast of California SpaceX is supposedly dickering over with the US Navy nor is the "Of Course I'll Still Love You". Which is only a single ASDS. But maybe the CA island issue is resolved. It's been awhile since I checked...
Dave
David Spain
Feb 3, 2015, 4:20:15 PM2/3/15
to
On Thursday, January 29, 2015 at 8:05:46 AM UTC-5, Rick Jones wrote:
> Jeff Findley <jfin...@cinci.nospam.rr.com> wrote:
> > The one thing I doubt we'll see in the test launch is all three of
> > the first stage cores landing at the launch site. As far as I know,
> > SpaceX does not yet have permission to land a core at The Cape. I'd
> > imagine permission to land three (two almost simultaneously) in
> > relatively close proximity will take an additional level of
> > permission beyond that.
>
> Heck, I doubt we'll see even one landing at the launch site. On the
> barge at sea, sure. The luddite in me would even wonder if there
> would be any first stage landing attempt on the first Falcon Heavy
> launch in the first place. Particularly if the first launch intends
> to demonstrate to the USAF/NRO/et al the maximum mass-to-orbit
> capabilities.
>
Agreed.
> Jeff Findley <jfin...@cinci.nospam.rr.com> wrote:
> > The one thing I doubt we'll see in the test launch is all three of
> > the first stage cores landing at the launch site. As far as I know,
> > SpaceX does not yet have permission to land a core at The Cape. I'd
> > imagine permission to land three (two almost simultaneously) in
> > relatively close proximity will take an additional level of
> > permission beyond that.
>
> Heck, I doubt we'll see even one landing at the launch site. On the
> barge at sea, sure. The luddite in me would even wonder if there
> would be any first stage landing attempt on the first Falcon Heavy
> launch in the first place. Particularly if the first launch intends
> to demonstrate to the USAF/NRO/et al the maximum mass-to-orbit
> capabilities.
>
If you build enough barges, err I mean "autonomous drone ships", ;-) I wonder if RTLS is that important. What's cheaper to trade off? RP-1/LOX vs payload to orbit or marine diesel-vs-time?
It's an interesting question. On the face of it, unless I've blown the gloss over math looks like prices are about a 2-to-1 ratio in favor of the rocket fuel! If Musk's figures for F9 are right. But then a tug isn't going to burn ALL 200K gallons on a single tow of only 500 miles round trip in light seas either. If it burns, let's say 40K gallons, that'd put it at $115K to tow in a F9 booster, we're already at 1/2 again the price of an F9 burn there. Hmmmm...
As I said, an interesting question....
Dave
> http://www.astronautix.com/props/loxosene.htm
> http://qz.com/153969/spacex-just-made-rocket-launches-affordable-heres-how-it-could-make-them-downright-cheap/
> http://www.waterwayguide.com/fuel-pricing/fwcklo
> http://www.crowley.com/ocean
David Spain
Feb 3, 2015, 8:26:31 PM2/3/15
to
On Tuesday, February 3, 2015 at 4:20:15 PM UTC-5, David Spain wrote:
> It's an interesting question. On the face of it, unless I've blown the gloss over math, [it] looks like prices are about a 2-to-1 ratio in favor of the rocket fuel! If Musk's figures for F9 are right. But then a tug isn't going to burn ALL 200K gallons on a single tow of only 500 miles round trip in light seas either. If it burns, let's say 40K gallons, that'd put it at $115K to tow in a F9 booster, we're already at 1/2 again the price of an F9 burn there. Hmmmm...
For the size and heft of the ASDS, even with an F9 first stage aboard, I gotta believe that fuel consumption figure is on the very high side of the mark. If the ASDS is modified to cruise itself via control from the command ship, the fuel economy might be also vastly improved.
The ocean-side of this equation is very interesting...
Dave
> It's an interesting question. On the face of it, unless I've blown the gloss over math, [it] looks like prices are about a 2-to-1 ratio in favor of the rocket fuel! If Musk's figures for F9 are right. But then a tug isn't going to burn ALL 200K gallons on a single tow of only 500 miles round trip in light seas either. If it burns, let's say 40K gallons, that'd put it at $115K to tow in a F9 booster, we're already at 1/2 again the price of an F9 burn there. Hmmmm...
For the size and heft of the ASDS, even with an F9 first stage aboard, I gotta believe that fuel consumption figure is on the very high side of the mark. If the ASDS is modified to cruise itself via control from the command ship, the fuel economy might be also vastly improved.
The ocean-side of this equation is very interesting...
Dave
David Spain
Feb 3, 2015, 8:38:07 PM2/3/15
to
On Tuesday, February 3, 2015 at 8:26:31 PM UTC-5, David Spain wrote:
>
> The ocean-side of this equation is very interesting...
>
> Dave
A side note on the issue:
>
> The ocean-side of this equation is very interesting...
>
> Dave
> http://www.professionalmariner.com/May-2008/Fuel-management-for-tugs-becoming-an-increasing-challenge/
Jeff Findley
Feb 3, 2015, 11:24:55 PM2/3/15
to
In article <886e19f8-605b-4b88...@googlegroups.com>,
david....@gmail.com says...
The Falcon 9 first stage uses 39,000 US gallons of kerosene. The above
article says that tugs can have diesel fuel tanks of "up to 100,000 or
more if intended for coastwise or offshore towing".
So, perhaps Musk isn't as crazy as everyone makes him out to be when you
take into account the costs of fuel and the other costs for the tugs and
barge. With a 100,000 tank, fueling an ocean going tug isn't at all
cheap.
david....@gmail.com says...
article says that tugs can have diesel fuel tanks of "up to 100,000 or
more if intended for coastwise or offshore towing".
So, perhaps Musk isn't as crazy as everyone makes him out to be when you
take into account the costs of fuel and the other costs for the tugs and
barge. With a 100,000 tank, fueling an ocean going tug isn't at all
cheap.
William Mook
Feb 4, 2015, 5:27:34 AM2/4/15
to
Each booster runs around $30 million. So, the Falcon Heavy runs around $100 million. Shotwell said that costs could drop to $7 million to $9 million range for reusable systems.
http://www.parabolicarc.com/2014/01/14/shotwell/
This is not the way to market that capability imho. You need to sell SpaceX as an expendable first, and then recover and refurbish as your expense. Then hold off selling them until someone wants to pay extra for a rapid response. Then turn around and point out the market price for a reusable is higher than for an expendable.
This is what you do 'early days'.
Then later days - as you accumulate an inventory of used rockets, you offer 'loss leaders' - as part of a customer loyalty programme.
Then, even later, and this all depends on launch rates, adoption rates, and so forth, you offer to launch vehicles 'at cost' ($7 to 9 mil) for a 'piece of the action' in assets that provide significant revenue. That is telecom networks, power networks, and mining operations. That way you have revenues independent of your launch rates.
You then funnel money into your vehicle development programmes.
You then funnel money into off-world assets.
Here's what Astronautix says about the Falcon & Falcon Heavy rockets -
In September 2006 SpaceX was named as one of two winners of the NASA Commercial Orbital Transportation Services competition. The SpaceX award was $278 million for three flight demonstrations of the Falcon 9 booster carrying the Dragon space capsule. On 23 December 2008 NASA announced that the Falcon 9 / Dragon had been selected for launch of a guaranteed minimum of 20,000 kg of payload to the International Space Station in 2010-2014. The firm contract was worth $1.6 billion, with another $1.5 billion of options.
Reliability of the Falcon 9 was assured by a hold-before-release system - the Falcon was held down and could not be released for flight until all propulsion and vehicle systems were confirmed to be operating normally. An automatic safe shut-down and unloading of propellant occurred if any off nominal conditions are detected. A Kevlar shield protects each engine from debris in the event of its neighbor failing. All Falcon designs had only two stages and only one stage separation event - the minimum practical. All stage separation bolts were all dual initiated, fully space qualified, and had a zero failure track record in prior launch vehicles. Guidance was by triple redundant flight computers and inertial navigation, with a GPS overlay for additional orbit insertion accuracy. The engines, structural materials and design principles, avionics and launch system were all to have been proven on earlier Falcon 1 flights before the first Falcon 9 was ever launched.
The Falcon 9 first and second stage tank walls and domes were made from aluminum 2219, using all friction stir welding. The interstage was made of a carbon fiber honeycomb structure. The separation system consisted of pyrotechnic release bolts and pneumatic separation pushers. Although in-flight failures are very rarely explosive, a Kevlar shield protects each engine from debris in the event of its neighbor failing.
LEO Payload: 10,450 kg (23,030 lb) to a 200 km orbit at 28.00 degrees.
Payload: 4,540 kg (10,000 lb) to a GTO, 28 deg.
Development Cost $: 378.000 million.
Launch Price $: 36.750 million in 2008 dollars in 2008 dollars.
Boost Propulsion: Lox/Kerosene.
Cruise Thrust: 66.600 kN (14,972 lbf) 6,800 kgf.
Cruise engine: Kestrel.
Initial Operational Capability: 2009.
Gross mass: 333,400 kg (735,000 lb).
Payload: 10,450 kg (23,030 lb).
Height: 55.00 m (180.00 ft).
Diameter: 3.60 m (11.80 ft).
Span: 3.60 m (11.80 ft).
Thrust: 5,560.00 kN (1,249,930 lbf).
Apogee: 200 km (120 mi).
First Launch: 2010.06.04.
The Falcon 9 Heavy consists of a standard Falcon 9 with two additional Falcon 9 first stages as liquid strap-on boosters.
The Falcon 9 first stage had been designed to support the additional loads of this configuration, with common tanking and engines across both vehicles. Initial architectural work had begun in 2008.
LEO Payload: 28,000 kg (61,000 lb) to a 200 km orbit at 28.00 degrees.
Payload: 12,000 kg (26,000 lb) to a GTO, 28 deg.
Boost Propulsion: Lox/Kerosene.
Cruise Thrust: 66.600 kN (14,972 lbf) 6,800 kgf.
Cruise engine: Kestrel.
Gross mass: 885,000 kg (1,951,000 lb).
Payload: 28,000 kg (61,000 lb).
Height: 54.90 m (180.10 ft).
Diameter: 3.60 m (11.80 ft).
Span: 3.60 m (11.80 ft).
Thrust: 15,000.00 kN (3,372,000 lbf).
Apogee: 200 km (120 mi).
http://www.parabolicarc.com/2014/01/14/shotwell/
This is not the way to market that capability imho. You need to sell SpaceX as an expendable first, and then recover and refurbish as your expense. Then hold off selling them until someone wants to pay extra for a rapid response. Then turn around and point out the market price for a reusable is higher than for an expendable.
This is what you do 'early days'.
Then later days - as you accumulate an inventory of used rockets, you offer 'loss leaders' - as part of a customer loyalty programme.
Then, even later, and this all depends on launch rates, adoption rates, and so forth, you offer to launch vehicles 'at cost' ($7 to 9 mil) for a 'piece of the action' in assets that provide significant revenue. That is telecom networks, power networks, and mining operations. That way you have revenues independent of your launch rates.
You then funnel money into your vehicle development programmes.
You then funnel money into off-world assets.
Here's what Astronautix says about the Falcon & Falcon Heavy rockets -
In September 2006 SpaceX was named as one of two winners of the NASA Commercial Orbital Transportation Services competition. The SpaceX award was $278 million for three flight demonstrations of the Falcon 9 booster carrying the Dragon space capsule. On 23 December 2008 NASA announced that the Falcon 9 / Dragon had been selected for launch of a guaranteed minimum of 20,000 kg of payload to the International Space Station in 2010-2014. The firm contract was worth $1.6 billion, with another $1.5 billion of options.
Reliability of the Falcon 9 was assured by a hold-before-release system - the Falcon was held down and could not be released for flight until all propulsion and vehicle systems were confirmed to be operating normally. An automatic safe shut-down and unloading of propellant occurred if any off nominal conditions are detected. A Kevlar shield protects each engine from debris in the event of its neighbor failing. All Falcon designs had only two stages and only one stage separation event - the minimum practical. All stage separation bolts were all dual initiated, fully space qualified, and had a zero failure track record in prior launch vehicles. Guidance was by triple redundant flight computers and inertial navigation, with a GPS overlay for additional orbit insertion accuracy. The engines, structural materials and design principles, avionics and launch system were all to have been proven on earlier Falcon 1 flights before the first Falcon 9 was ever launched.
The Falcon 9 first and second stage tank walls and domes were made from aluminum 2219, using all friction stir welding. The interstage was made of a carbon fiber honeycomb structure. The separation system consisted of pyrotechnic release bolts and pneumatic separation pushers. Although in-flight failures are very rarely explosive, a Kevlar shield protects each engine from debris in the event of its neighbor failing.
LEO Payload: 10,450 kg (23,030 lb) to a 200 km orbit at 28.00 degrees.
Payload: 4,540 kg (10,000 lb) to a GTO, 28 deg.
Development Cost $: 378.000 million.
Launch Price $: 36.750 million in 2008 dollars in 2008 dollars.
Boost Propulsion: Lox/Kerosene.
Cruise Thrust: 66.600 kN (14,972 lbf) 6,800 kgf.
Cruise engine: Kestrel.
Initial Operational Capability: 2009.
Gross mass: 333,400 kg (735,000 lb).
Payload: 10,450 kg (23,030 lb).
Height: 55.00 m (180.00 ft).
Diameter: 3.60 m (11.80 ft).
Span: 3.60 m (11.80 ft).
Thrust: 5,560.00 kN (1,249,930 lbf).
Apogee: 200 km (120 mi).
First Launch: 2010.06.04.
The Falcon 9 Heavy consists of a standard Falcon 9 with two additional Falcon 9 first stages as liquid strap-on boosters.
The Falcon 9 first stage had been designed to support the additional loads of this configuration, with common tanking and engines across both vehicles. Initial architectural work had begun in 2008.
LEO Payload: 28,000 kg (61,000 lb) to a 200 km orbit at 28.00 degrees.
Payload: 12,000 kg (26,000 lb) to a GTO, 28 deg.
Boost Propulsion: Lox/Kerosene.
Cruise Thrust: 66.600 kN (14,972 lbf) 6,800 kgf.
Cruise engine: Kestrel.
Gross mass: 885,000 kg (1,951,000 lb).
Payload: 28,000 kg (61,000 lb).
Height: 54.90 m (180.10 ft).
Diameter: 3.60 m (11.80 ft).
Span: 3.60 m (11.80 ft).
Thrust: 15,000.00 kN (3,372,000 lbf).
Apogee: 200 km (120 mi).
David Spain
Feb 4, 2015, 11:17:50 AM2/4/15
to
On Tuesday, February 3, 2015 at 11:24:55 PM UTC-5, Jeff Findley wrote:
> In article <886e19f8-605b-4b88...@googlegroups.com>,
> david.l.spain says...
> http://www.crowley.com/var/ezflow_site/storage/images/media/images/background-images/ocean-towing/67140-1-eng-US/Ocean-Towing.png
The ASDS hardly qualifies as a drilling platform. Now admittedly I'm drawing from my ag. background as a teen and the big CAT engines in these tugs are far far bigger than anything I used, BUT... 10,000 gallons of diesel is A LOT of fuel. I can't help shrug the feeling that towing the ASDS out to sea and back (forget the mass of the F9 booster, that's in the noise here) would take any more than that. In fact I'm thinking closer to 6000 gallons. Anybody from the marine towing business reading this? The ASDS masses and draws (according to Wikipedia):
Tonnage: 4,422 GT,[1] 1,326 NT,[1] 10,105 LT DWT[7]
Length: 288 ft (87.8 m)[1]
Beam: 100 ft (30.5 m)[1]
Depth: 19.8 ft (6.0 m)[1]
The F9 Stage 1 - 9R slightly heavier? (inert mass):
Type Falcon 9 v1.1 Stage 1
Length ~42m
Diameter 3.66m
Inert Mass ~18,000kg
Propellant Mass ~385,000kg <- only a fraction of this on return
Figure calm seas. This thing isn't going to be landed in heavy seas.
Dave
> http://www.spaceflight101.com/falcon-9-v11.html
> http://en.wikipedia.org/wiki/Autonomous_spaceport_drone_ship
> In article <886e19f8-605b-4b88...@googlegroups.com>,
> david.l.spain says...
> >
> > On Tuesday, February 3, 2015 at 8:26:31 PM UTC-5, David Spain wrote:
> > >
> > > The ocean-side of this equation is very interesting...
> > >
> > > Dave
> >
> > A side note on the issue:
> >
> > > http://www.professionalmariner.com/May-2008/Fuel-management-for-tugs-becoming-an-increasing-challenge/
>
> The Falcon 9 first stage uses 39,000 US gallons of kerosene. The above
> article says that tugs can have diesel fuel tanks of "up to 100,000 or
> more if intended for coastwise or offshore towing".
>
> So, perhaps Musk isn't as crazy as everyone makes him out to be when you
> take into account the costs of fuel and the other costs for the tugs and
> barge. With a 100,000 tank, fueling an ocean going tug isn't at all
> cheap.
>
> Jeff
No it isn't. However... Take a look at what these things are towing when they are consuming in the 5/6 figures of gallons.
> > On Tuesday, February 3, 2015 at 8:26:31 PM UTC-5, David Spain wrote:
> > >
> > > The ocean-side of this equation is very interesting...
> > >
> > > Dave
> >
> > A side note on the issue:
> >
> > > http://www.professionalmariner.com/May-2008/Fuel-management-for-tugs-becoming-an-increasing-challenge/
>
> The Falcon 9 first stage uses 39,000 US gallons of kerosene. The above
> article says that tugs can have diesel fuel tanks of "up to 100,000 or
> more if intended for coastwise or offshore towing".
>
> So, perhaps Musk isn't as crazy as everyone makes him out to be when you
> take into account the costs of fuel and the other costs for the tugs and
> barge. With a 100,000 tank, fueling an ocean going tug isn't at all
> cheap.
>
> Jeff
> http://www.crowley.com/var/ezflow_site/storage/images/media/images/background-images/ocean-towing/67140-1-eng-US/Ocean-Towing.png
The ASDS hardly qualifies as a drilling platform. Now admittedly I'm drawing from my ag. background as a teen and the big CAT engines in these tugs are far far bigger than anything I used, BUT... 10,000 gallons of diesel is A LOT of fuel. I can't help shrug the feeling that towing the ASDS out to sea and back (forget the mass of the F9 booster, that's in the noise here) would take any more than that. In fact I'm thinking closer to 6000 gallons. Anybody from the marine towing business reading this? The ASDS masses and draws (according to Wikipedia):
Tonnage: 4,422 GT,[1] 1,326 NT,[1] 10,105 LT DWT[7]
Length: 288 ft (87.8 m)[1]
Beam: 100 ft (30.5 m)[1]
Depth: 19.8 ft (6.0 m)[1]
The F9 Stage 1 - 9R slightly heavier? (inert mass):
Type Falcon 9 v1.1 Stage 1
Length ~42m
Diameter 3.66m
Inert Mass ~18,000kg
Propellant Mass ~385,000kg <- only a fraction of this on return
Figure calm seas. This thing isn't going to be landed in heavy seas.
Dave
> http://www.spaceflight101.com/falcon-9-v11.html
> http://en.wikipedia.org/wiki/Autonomous_spaceport_drone_ship
David Spain
Feb 4, 2015, 1:29:44 PM2/4/15
to
On Wednesday, February 4, 2015 at 11:17:50 AM UTC-5, David Spain wrote:
> The ASDS masses and draws (according to Wikipedia):
>
> Tonnage: 4,422 GT,[1] 1,326 NT,[1] 10,105 LT DWT[7]
> Length: 288 ft (87.8 m)[1]
> Beam: 100 ft (30.5 m)[1]
> Depth: 19.8 ft (6.0 m)[1]
>
Ah crap, Wikipedia is playing games again. They have double table entries for Length and Beam. One for the Marmac barge unmodified (above figures) and another set for it post modification to the ASDS which I list below (before some bright smart ass corrects me):
> The ASDS masses and draws (according to Wikipedia):
>
> Tonnage: 4,422 GT,[1] 1,326 NT,[1] 10,105 LT DWT[7]
> Length: 288 ft (87.8 m)[1]
> Beam: 100 ft (30.5 m)[1]
> Depth: 19.8 ft (6.0 m)[1]
>
Length: 300 ft (91.4 m)[8]
Beam: 170 ft (51.8 m)[8]
Depth: 19.8 ft (6.0 m)[1]
They don't list different tonnage figures tho. Nothing like consistency. When it comes to Wikipedia, you get what you pay for!
> > http://en.wikipedia.org/wiki/Autonomous_spaceport_drone_ship
Dave
Jeff Findley
Feb 5, 2015, 5:30:05 PM2/5/15
to
In article <2f9408dc-af77-49f2...@googlegroups.com>,
david....@gmail.com says...
pushing/towing a barge like the ASDS out to the landing location and
back to the launch site. Whether or not to land at the launch site
versus on the ASDS depends on a lot of factors. But given the
construction of landing sites close to the launch site, I'm going to
have some faith that SpaceX has done the engineering and cost trades to
determine that landing on a concrete pad is preferable, even if it
results in some payload degradation.
That said, I've read SpaceX is building another ASDS for use at
Vandenberg. I've also read that they're upping the performance of the
Merlin 1D (presumably so Falcon 9 can handle larger payloads, such as
from DOD). This would also give more margins on lower payload launches,
increasing the amount of LOX/kerosene available for boost back and
landing.
david....@gmail.com says...
>
> On Tuesday, February 3, 2015 at 11:24:55 PM UTC-5, Jeff Findley wrote:
> >
> > The Falcon 9 first stage uses 39,000 US gallons of kerosene. The above
> > article says that tugs can have diesel fuel tanks of "up to 100,000 or
> > more if intended for coastwise or offshore towing".
> >
> > So, perhaps Musk isn't as crazy as everyone makes him out to be when you
> > take into account the costs of fuel and the other costs for the tugs and
> > barge. With a 100,000 tank, fueling an ocean going tug isn't at all
> > cheap.
>
> On Tuesday, February 3, 2015 at 11:24:55 PM UTC-5, Jeff Findley wrote:
> >
> > The Falcon 9 first stage uses 39,000 US gallons of kerosene. The above
> > article says that tugs can have diesel fuel tanks of "up to 100,000 or
> > more if intended for coastwise or offshore towing".
> >
> > So, perhaps Musk isn't as crazy as everyone makes him out to be when you
> > take into account the costs of fuel and the other costs for the tugs and
> > barge. With a 100,000 tank, fueling an ocean going tug isn't at all
> > cheap.
>
> No it isn't. However... Take a look at what these things are towing when they are consuming in the 5/6 figures of gallons.
>
> > http://www.crowley.com/var/ezflow_site/storage/images/media/images/background-images/ocean-towing/67140-1-eng-US/Ocean-Towing.png
>
> The ASDS hardly qualifies as a drilling platform. Now admittedly I'm drawing from my ag. background as a teen and the big CAT engines in these tugs are far far bigger than anything I used, BUT... 10,000 gallons of diesel is A LOT of fuel. I can't help shrug the feeling that towing the ASDS out to sea and back (forget the mass of the F9 booster, that's in the noise here) would take any more than that. In fact I'm thinking closer to 6000 gallons. Anybody from the marine
towing business reading this? The ASDS masses and draws (according to Wikipedia):
>
> Tonnage: 4,422 GT,[1] 1,326 NT,[1] 10,105 LT DWT[7]
> Length: 288 ft (87.8 m)[1]
> Beam: 100 ft (30.5 m)[1]
> Depth: 19.8 ft (6.0 m)[1]
>
> The F9 Stage 1 - 9R slightly heavier? (inert mass):
> Type Falcon 9 v1.1 Stage 1
> Length ~42m
> Diameter 3.66m
> Inert Mass ~18,000kg
> Propellant Mass ~385,000kg <- only a fraction of this on return
>
> Figure calm seas. This thing isn't going to be landed in heavy seas.
>
> Dave
>
> > http://www.spaceflight101.com/falcon-9-v11.html
> > http://en.wikipedia.org/wiki/Autonomous_spaceport_drone_ship
I admit that I know nothing about fuel consumption of tugs
>
> > http://www.crowley.com/var/ezflow_site/storage/images/media/images/background-images/ocean-towing/67140-1-eng-US/Ocean-Towing.png
>
> The ASDS hardly qualifies as a drilling platform. Now admittedly I'm drawing from my ag. background as a teen and the big CAT engines in these tugs are far far bigger than anything I used, BUT... 10,000 gallons of diesel is A LOT of fuel. I can't help shrug the feeling that towing the ASDS out to sea and back (forget the mass of the F9 booster, that's in the noise here) would take any more than that. In fact I'm thinking closer to 6000 gallons. Anybody from the marine
towing business reading this? The ASDS masses and draws (according to Wikipedia):
>
> Tonnage: 4,422 GT,[1] 1,326 NT,[1] 10,105 LT DWT[7]
> Length: 288 ft (87.8 m)[1]
> Beam: 100 ft (30.5 m)[1]
> Depth: 19.8 ft (6.0 m)[1]
>
> The F9 Stage 1 - 9R slightly heavier? (inert mass):
> Type Falcon 9 v1.1 Stage 1
> Length ~42m
> Diameter 3.66m
> Inert Mass ~18,000kg
> Propellant Mass ~385,000kg <- only a fraction of this on return
>
> Figure calm seas. This thing isn't going to be landed in heavy seas.
>
> Dave
>
> > http://www.spaceflight101.com/falcon-9-v11.html
> > http://en.wikipedia.org/wiki/Autonomous_spaceport_drone_ship
pushing/towing a barge like the ASDS out to the landing location and
back to the launch site. Whether or not to land at the launch site
versus on the ASDS depends on a lot of factors. But given the
construction of landing sites close to the launch site, I'm going to
have some faith that SpaceX has done the engineering and cost trades to
determine that landing on a concrete pad is preferable, even if it
results in some payload degradation.
That said, I've read SpaceX is building another ASDS for use at
Vandenberg. I've also read that they're upping the performance of the
Merlin 1D (presumably so Falcon 9 can handle larger payloads, such as
from DOD). This would also give more margins on lower payload launches,
increasing the amount of LOX/kerosene available for boost back and
landing.
David Spain
Feb 5, 2015, 8:21:55 PM2/5/15
to
On Thursday, February 5, 2015 at 5:30:05 PM UTC-5, Jeff Findley wrote:
> That said, I've read SpaceX is building another ASDS for use at
> Vandenberg. I've also read that they're upping the performance of the
> Merlin 1D (presumably so Falcon 9 can handle larger payloads, such as
> from DOD). This would also give more margins on lower payload launches,
> increasing the amount of LOX/kerosene available for boost back and
> landing.
>
> Jeff
> --
That may be. And I shouldn't second guess SpaceX at their own business. But it still seems to be somewhat backwards to fuel for recovery with a bi-propellant of more expensive (than marine diesel) RP-1 and the additional LOX in place of mono-propellant diesel, IF it's cheaper in the end. And that really depends on how much is consumed by that tug. I mean if you don't have to fuel for RTLS then you can save that for what really counts the most for the customer and that is payload to orbit. Thus if you fuel less (or for less) you can *always* charge less. But then you have also to factor in the fixed overhead for a marine operation. If you can get rid of the ASDS tug and have it self propel under control of the command ship that would be an additional source of savings. It's fascinating to me, since, well since in aerospace, until now, we've never really had to deal with multi-modal recovery transport options that have to return a profit!
> That said, I've read SpaceX is building another ASDS for use at
> Vandenberg. I've also read that they're upping the performance of the
> Merlin 1D (presumably so Falcon 9 can handle larger payloads, such as
> from DOD). This would also give more margins on lower payload launches,
> increasing the amount of LOX/kerosene available for boost back and
> landing.
>
> Jeff
> --
I'd LOVE to see the numbers, but of course I'm sure that's proprietary info!
I've seen scuttlebutt elsewhere that the 2nd (Pacific) ASDS will be used primarily for core booster recovery on the F9H-R, because it would not be feasible (or economical?) to attempt RTLS with the core booster. I would guess because, for at least for certain flight profiles, the downrange distance is too far to be economical or feasible to do a powered booster return.
Dave
William Mook
Feb 6, 2015, 4:57:14 PM2/6/15
to
On Wednesday, February 4, 2015 at 11:17:50 AM UTC-5, David Spain wrote:
Fuel Consumption of large ships:
https://people.hofstra.edu/geotrans/eng/ch8en/conc8en/fuel_consumption_containerships.html
Details about the recovery platform:
http://en.wikipedia.org/wiki/Autonomous_spaceport_drone_ship
Marine fuel prices:
http://www.bunkerindex.com/prices/bixfree.php?priceindex_id=4
Alright...
The platform masses 10,000 tons and consumes about 150 tons per day of fuel when its underway at 21 knots. That's 6.25 tons per hour moving at 40 km/hr. That's 0.157 tons per km.
The ship operates 366 km away from the launch center at the point of recovery. So, the ship has to travel a 732 km round trip. 366 km out. 366 km back.
Thus, it will consume about 115 tons in transit. Add another 10 tons for station keeping and power generation, and you have 125 tons for recovery.
The cost of each ton of fuel is $603 - so that's a total cost of $75,375 per recovery.
Contrast this cost with the construction cost of a booster is in the $35 million. Or to the cost of rebuilding the booster and recertifying it for relaunch.
According to SpaceX President Gwynne Shotwell, it will cost $5 million to $7 million to recover and rebuild a booster certifying it for re-launch.
http://www.parabolicarc.com/2014/01/14/shotwell/
The cost of fuel to power the recovery platform and tow it around is 1% of this total.
http://images.forbes.com/special-report/2012/assets/img/gwynne-shotwell.jpg
So, this hand wringing over the exorbitant cost of moving empty boosters across the ocean is laughable in this context.
Rick Jones
Feb 9, 2015, 5:06:29 AM2/9/15
to
Jeff Findley <jfin...@cinci.nospam.rr.com> wrote:
> In article <886e19f8-605b-4b88...@googlegroups.com>,
> In article <886e19f8-605b-4b88...@googlegroups.com>,
> > > http://www.professionalmariner.com/May-2008/Fuel-management-for-tugs-becoming-an-increasing-challenge/
> The Falcon 9 first stage uses 39,000 US gallons of kerosene. The
> above article says that tugs can have diesel fuel tanks of "up to
> 100,000 or more if intended for coastwise or offshore towing".
> So, perhaps Musk isn't as crazy as everyone makes him out to be when
> you take into account the costs of fuel and the other costs for the
> tugs and barge. With a 100,000 tank, fueling an ocean going tug
> isn't at all cheap.
But how many trips is that tank going to get you? From David's link
> The Falcon 9 first stage uses 39,000 US gallons of kerosene. The
> above article says that tugs can have diesel fuel tanks of "up to
> 100,000 or more if intended for coastwise or offshore towing".
> So, perhaps Musk isn't as crazy as everyone makes him out to be when
> you take into account the costs of fuel and the other costs for the
> tugs and barge. With a 100,000 tank, fueling an ocean going tug
> isn't at all cheap.
it seems to say 3,000 to 5,000 gallons of fuel per day towing an ocean
barge (in 2008 and talking about more efficient engines being
deployed). How many days' sailing (round-trip I presume) are these
landing sites? And I think David has already suggested it would
probably be the lower end of the range if not below it given how
little mass beyond the barge itself there would be.
rick jones
--
firebug n, the idiot who tosses a lit cigarette out his car window
Jeff Findley
Feb 9, 2015, 5:55:24 AM2/9/15
to
In article <maubii$fgq$1...@usenet01.boi.hp.com>, rick....@hp.com
says...
interesting to track how many days the barge takes to get back to
Florida and multiply by two to get a very rough estimate for round trip
time in days. The last time, there were pictures posted on Reddit when
the barge arrived.
says...
>
> Jeff Findley <jfin...@cinci.nospam.rr.com> wrote:
> > In article <886e19f8-605b-4b88...@googlegroups.com>,
> > > > http://www.professionalmariner.com/May-2008/Fuel-management-for-tugs-becoming-an-increasing-challenge/
>
> > The Falcon 9 first stage uses 39,000 US gallons of kerosene. The
> > above article says that tugs can have diesel fuel tanks of "up to
> > 100,000 or more if intended for coastwise or offshore towing".
>
> > So, perhaps Musk isn't as crazy as everyone makes him out to be when
> > you take into account the costs of fuel and the other costs for the
> > tugs and barge. With a 100,000 tank, fueling an ocean going tug
> > isn't at all cheap.
>
> But how many trips is that tank going to get you? From David's link
> it seems to say 3,000 to 5,000 gallons of fuel per day towing an ocean
> barge (in 2008 and talking about more efficient engines being
> deployed). How many days' sailing (round-trip I presume) are these
> landing sites? And I think David has already suggested it would
> probably be the lower end of the range if not below it given how
> little mass beyond the barge itself there would be.
Agreed, I don't know for sure. On this next launch, it would be
> Jeff Findley <jfin...@cinci.nospam.rr.com> wrote:
> > In article <886e19f8-605b-4b88...@googlegroups.com>,
> > > > http://www.professionalmariner.com/May-2008/Fuel-management-for-tugs-becoming-an-increasing-challenge/
>
> > The Falcon 9 first stage uses 39,000 US gallons of kerosene. The
> > above article says that tugs can have diesel fuel tanks of "up to
> > 100,000 or more if intended for coastwise or offshore towing".
>
> > So, perhaps Musk isn't as crazy as everyone makes him out to be when
> > you take into account the costs of fuel and the other costs for the
> > tugs and barge. With a 100,000 tank, fueling an ocean going tug
> > isn't at all cheap.
>
> But how many trips is that tank going to get you? From David's link
> it seems to say 3,000 to 5,000 gallons of fuel per day towing an ocean
> barge (in 2008 and talking about more efficient engines being
> deployed). How many days' sailing (round-trip I presume) are these
> landing sites? And I think David has already suggested it would
> probably be the lower end of the range if not below it given how
> little mass beyond the barge itself there would be.
interesting to track how many days the barge takes to get back to
Florida and multiply by two to get a very rough estimate for round trip
time in days. The last time, there were pictures posted on Reddit when
the barge arrived.
Niels Jørgen Kruse
Feb 9, 2015, 8:07:51 AM2/9/15
to
Jeff Findley <jfin...@cinci.nospam.rr.com> wrote:
> In article <maubii$fgq$1...@usenet01.boi.hp.com>, rick....@hp.com
> says...
hurry moving the landing barge around.
--
Mvh./Regards, Niels Jørgen Kruse, Vanløse, Denmark
> In article <maubii$fgq$1...@usenet01.boi.hp.com>, rick....@hp.com
> says...
> >
> > But how many trips is that tank going to get you? From David's link
> > it seems to say 3,000 to 5,000 gallons of fuel per day towing an ocean
> > barge (in 2008 and talking about more efficient engines being
> > deployed). How many days' sailing (round-trip I presume) are these
> > landing sites? And I think David has already suggested it would
> > probably be the lower end of the range if not below it given how
> > little mass beyond the barge itself there would be.
>
> Agreed, I don't know for sure. On this next launch, it would be
> interesting to track how many days the barge takes to get back to
> Florida and multiply by two to get a very rough estimate for round trip
> time in days. The last time, there were pictures posted on Reddit when
> the barge arrived.
Fuel consumption depends a lot on speed. There is no need to be in a
> > But how many trips is that tank going to get you? From David's link
> > it seems to say 3,000 to 5,000 gallons of fuel per day towing an ocean
> > barge (in 2008 and talking about more efficient engines being
> > deployed). How many days' sailing (round-trip I presume) are these
> > landing sites? And I think David has already suggested it would
> > probably be the lower end of the range if not below it given how
> > little mass beyond the barge itself there would be.
>
> Agreed, I don't know for sure. On this next launch, it would be
> interesting to track how many days the barge takes to get back to
> Florida and multiply by two to get a very rough estimate for round trip
> time in days. The last time, there were pictures posted on Reddit when
> the barge arrived.
hurry moving the landing barge around.
--
Mvh./Regards, Niels Jørgen Kruse, Vanløse, Denmark
David Spain
Feb 9, 2015, 10:36:33 AM2/9/15
to
On Monday, February 9, 2015 at 5:55:24 AM UTC-5, Jeff Findley wrote:
> In article <>, rick.jones2
> says...
So for launch delays, here's an argument -> in favor <- of RTLS.
But if the Shotwell quotes are correct, with refurbishment cost in the $3-5 million range, per launch, I guess fuel consumption is well in the noise here.
If launch rates were to increase tho, other logistics might come into play. I still think it is an interesting topic.
Dave
> In article <>, rick.jones2
> says...
> >
> > Jeff Findley <> wrote:
> > > In article <886e19f8-605b-4b88...@googlegroups.com>,
> > > > > http://www.professionalmariner.com/May-2008/Fuel-management-for-tugs-becoming-an-increasing-challenge/
> >
> > > The Falcon 9 first stage uses 39,000 US gallons of kerosene. The
> > > above article says that tugs can have diesel fuel tanks of "up to
> > > 100,000 or more if intended for coastwise or offshore towing".
> >
> > > So, perhaps Musk isn't as crazy as everyone makes him out to be when
> > > you take into account the costs of fuel and the other costs for the
> > > tugs and barge. With a 100,000 tank, fueling an ocean going tug
> > > isn't at all cheap.
> >
> > But how many trips is that tank going to get you? From David's link
> > it seems to say 3,000 to 5,000 gallons of fuel per day towing an ocean
> > barge (in 2008 and talking about more efficient engines being
> > deployed). How many days' sailing (round-trip I presume) are these
> > landing sites? And I think David has already suggested it would
> > probably be the lower end of the range if not below it given how
> > little mass beyond the barge itself there would be.
>
> Agreed, I don't know for sure. On this next launch, it would be
> interesting to track how many days the barge takes to get back to
> Florida and multiply by two to get a very rough estimate for round trip
> time in days. The last time, there were pictures posted on Reddit when
> the barge arrived.
>
> Jeff
And then there is the fuel the ASDS itself uses station-keeping in the ocean. In this case it will be a little higher than the norm if they are using the thrusters to station keep for the extra day. I'm assuming they are diesel electric. Or even if the tug has to intervene and tow in circles a bit, the ocean fuel consumption will be higher than "normal" for this flight.
> > Jeff Findley <> wrote:
> > > In article <886e19f8-605b-4b88...@googlegroups.com>,
> > > > > http://www.professionalmariner.com/May-2008/Fuel-management-for-tugs-becoming-an-increasing-challenge/
> >
> > > The Falcon 9 first stage uses 39,000 US gallons of kerosene. The
> > > above article says that tugs can have diesel fuel tanks of "up to
> > > 100,000 or more if intended for coastwise or offshore towing".
> >
> > > So, perhaps Musk isn't as crazy as everyone makes him out to be when
> > > you take into account the costs of fuel and the other costs for the
> > > tugs and barge. With a 100,000 tank, fueling an ocean going tug
> > > isn't at all cheap.
> >
> > But how many trips is that tank going to get you? From David's link
> > it seems to say 3,000 to 5,000 gallons of fuel per day towing an ocean
> > barge (in 2008 and talking about more efficient engines being
> > deployed). How many days' sailing (round-trip I presume) are these
> > landing sites? And I think David has already suggested it would
> > probably be the lower end of the range if not below it given how
> > little mass beyond the barge itself there would be.
>
> Agreed, I don't know for sure. On this next launch, it would be
> interesting to track how many days the barge takes to get back to
> Florida and multiply by two to get a very rough estimate for round trip
> time in days. The last time, there were pictures posted on Reddit when
> the barge arrived.
>
> Jeff
So for launch delays, here's an argument -> in favor <- of RTLS.
But if the Shotwell quotes are correct, with refurbishment cost in the $3-5 million range, per launch, I guess fuel consumption is well in the noise here.
If launch rates were to increase tho, other logistics might come into play. I still think it is an interesting topic.
Dave
David Spain
Feb 9, 2015, 10:40:14 AM2/9/15
to
On Monday, February 9, 2015 at 10:36:33 AM UTC-5, David Spain wrote:
> But if the Shotwell quotes are correct, with refurbishment cost in the $3-5 million range, per launch, I guess fuel consumption is well in the noise here.
Erm, I meant 7-9 million.
> But if the Shotwell quotes are correct, with refurbishment cost in the $3-5 million range, per launch, I guess fuel consumption is well in the noise here.
Dave
Rick Jones
Feb 9, 2015, 5:01:07 PM2/9/15
to
> > So, perhaps Musk isn't as crazy as everyone makes him out to be
> > when you take into account the costs of fuel and the other costs
> > for the tugs and barge. With a 100,000 tank, fueling an ocean
> > going tug isn't at all cheap.
> But how many trips is that tank going to get you? From David's link
> it seems to say 3,000 to 5,000 gallons of fuel per day towing an
> ocean barge (in 2008 and talking about more efficient engines being
> deployed). How many days' sailing (round-trip I presume) are these
> landing sites? And I think David has already suggested it would
> probably be the lower end of the range if not below it given how
> little mass beyond the barge itself there would be.
http://abcnews.go.com/Technology/wireStory/rocket-booster-aiming-ocean-barge-redo-spacex-test-28800420
> > when you take into account the costs of fuel and the other costs
> > for the tugs and barge. With a 100,000 tank, fueling an ocean
> > going tug isn't at all cheap.
> But how many trips is that tank going to get you? From David's link
> it seems to say 3,000 to 5,000 gallons of fuel per day towing an
> ocean barge (in 2008 and talking about more efficient engines being
> deployed). How many days' sailing (round-trip I presume) are these
> landing sites? And I think David has already suggested it would
> probably be the lower end of the range if not below it given how
> little mass beyond the barge itself there would be.
suggests that for the DSCVR launch the barge was going to be 370
nautical miles away. I suspect that varies with the launch profile of
course.
rick jones
--
Process shall set you free from the need for rational thought.
David Spain
Feb 13, 2015, 6:50:16 PM2/13/15
to
The DSCOVR launch also provides another compelling reason for RTLS. Bad weather at the recovery site. If the weather is good enough at the launch site for a launch it is unlikely to go bad enough to prevent a landing in the time it takes for a booster to return.
Saving $$$ on fuel doesn't help if you are forced to put it down in the ocean.
Dave
Saving $$$ on fuel doesn't help if you are forced to put it down in the ocean.
Dave
Jeff Findley
Feb 15, 2015, 10:07:41 AM2/15/15
to
In article <6bd3780b-78b6-4b5a...@googlegroups.com>,
david....@gmail.com says...
something goes wrong, like an engine out, the fuel which would have been
used for landing would be burned in order to successfully accomplish the
primary mission. That's the entire idea since the beginning of the
Falcon 9R program; use the "reserve" in your fuel budget for boost back
and landing. Other launchers use this to help better aim the stages for
destructive reentry or simply let it go "splat" on the ocean or on land.
In other words, losing a first stage now and then would not be the end
of the world. In fact, they're losing a first stage on *every* mission
today, and are still profitable. You handle that by having several
completed first stages ready to go. I'd want three spare stages
*minimum* to handle the loss of a Falcon Heavy. But that's me. Musk
may have other ideas on how to mitigate risk.
david....@gmail.com says...
>
> The DSCOVR launch also provides another compelling reason for RTLS. Bad weather at the recovery site. If the weather is good enough at the launch site for a launch it is unlikely to go bad enough to prevent a landing in the time it takes for a booster to return.
>
> Saving $$$ on fuel doesn't help if you are forced to put it down in the ocean.
"Forced" would seem to indicate that something has gone wrong. If
> The DSCOVR launch also provides another compelling reason for RTLS. Bad weather at the recovery site. If the weather is good enough at the launch site for a launch it is unlikely to go bad enough to prevent a landing in the time it takes for a booster to return.
>
> Saving $$$ on fuel doesn't help if you are forced to put it down in the ocean.
something goes wrong, like an engine out, the fuel which would have been
used for landing would be burned in order to successfully accomplish the
primary mission. That's the entire idea since the beginning of the
Falcon 9R program; use the "reserve" in your fuel budget for boost back
and landing. Other launchers use this to help better aim the stages for
destructive reentry or simply let it go "splat" on the ocean or on land.
In other words, losing a first stage now and then would not be the end
of the world. In fact, they're losing a first stage on *every* mission
today, and are still profitable. You handle that by having several
completed first stages ready to go. I'd want three spare stages
*minimum* to handle the loss of a Falcon Heavy. But that's me. Musk
may have other ideas on how to mitigate risk.
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