View source for RatSat

{{Short description|Mass simulator on fourth Falcon 1 flight}}
{{Infobox spaceflight
| name               = RatSat
| image              = RatSat Falcon 1.png
| image_caption      = RatSat, with a SpaceX sticker and its mission logo
| mission_type       = Launch demonstration
| operator           = [[SpaceX]]
| COSPAR_ID          = 2008-048A
| SATCAT             = 33393
| mission_duration = {{time interval|28 September 2008, 23:15|show=ymd|sep=,}} (in orbit)
| manufacturer       = [[SpaceX]]
| launch_mass        = {{Cvt|165|kg|lb}}<ref name=":0" />
| dimensions         = {{convert|1.5|m|ft|abbr=on}} in length
| launch_date        = {{start-date|28 September 2008, 23:15|timezone=yes}}&nbsp;UTC
| launch_rocket      = [[Falcon 1]]
| launch_site        = [[Omelek Island]]
| launch_contractor  = [[SpaceX]]
| decay_date         = <!-- {{end-date|[insert date here]}} -->
| orbit_epoch        = 24 January 2015, 18:58:23&nbsp;UTC<ref name="n2yo">{{cite web|url=http://www.n2yo.com/satellite/?s=33393|title=DEMOSAT/FALCON 1 Satellite details 2008-048A NORAD 33393|publisher=N2YO|date=24 January 2015|access-date=25 January 2015|archive-date=22 September 2015|archive-url=https://web.archive.org/web/20150922053152/http://www.n2yo.com/satellite/?s=33393|url-status=live}}</ref>
| previous_mission   = [[Falcon_1#Third_flight|Falcon 1 flight 3]]
| next_mission       = [[RazakSAT]]
| auto               = all
| orbit_regime       = [[Low Earth orbit]]
| orbit_periapsis    = {{convert|617|km|mi|sp=us}}<ref name="n2yo"/>
| orbit_apoapsis     = {{convert|635|km|mi|sp=us}}<ref name="n2yo"/>
| orbit_inclination  = 9.35°<ref name="n2yo"/>
| orbit_period       = 97.09&nbsp;minutes<ref name="n2yo"/>
| apsis              = gee
}}
'''RatSat'''<ref name=":0">{{Cite book |last=Berger |first=Eric |url= |title=Liftoff: Elon Musk and the Desperate Early Days That Launched SpaceX |date=March 2, 2021 |publisher=[[William Morrow and Company]] |isbn=978-0-00-844562-1 |location=London |oclc=1233312066 |author-link=Eric Berger (meteorologist)}}</ref>{{Rp|page=184}} or '''DemoSat'''<ref name="NSSDC 2008-048A">{{cite web|url=https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=2008-048A|title=DemoSat, NSSDC ID: 2008-048A|publisher=NASA NSSDC|date=2008-09-28|access-date=2012-08-24|archive-date=2020-10-24|archive-url=https://web.archive.org/web/20201024175723/https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=2008-048A|url-status=live}}</ref>
is an [[Aluminium|aluminum]] mass simulator on the fourth flight of the [[Falcon 1]] rocket, launched on 28 September 2008. Ratsat<ref name="JSR 601">{{cite web |last=McDowell |first=Jonathan |date=2008-09-26 |title=Issue 601 |url=http://host.planet4589.org/space/jsr/back/news.601 |url-status=dead |archive-url=https://web.archive.org/web/20090826061037/http://host.planet4589.org/space/jsr/back/news.601 |archive-date=2009-08-26 |access-date=2008-09-29 |publisher=[[Jonathan's Space Report]]}}</ref> remained bolted to the second stage of the carrier rocket after reaching [[low Earth orbit]].<ref name="SFN preview">{{cite web |last=Clark |first=Stephen |date=2008-09-27 |title=SpaceX to launch its fourth Falcon 1 rocket on Sunday |url=http://www.spaceflightnow.com/falcon/004/080927preview.html |access-date=2008-09-28 |publisher=Spaceflight Now |archive-date=2008-12-19 |archive-url=https://web.archive.org/web/20081219101451/http://spaceflightnow.com/falcon/004/080927preview.html |url-status=live }}</ref> It is an [[aluminium]] alloy chamber in [[hexagonal prism]] shape with 1.5&nbsp;m (5&nbsp;ft) length.<ref name="Press release">{{cite web |title=Press Release: SpaceX Successfully Launches Falcon 1 to Orbit |url=http://www.spacex.com/press.php?page=20080928 |url-status=dead |archive-url=https://web.archive.org/web/20130126130419/http://www.spacex.com/press.php?page=20080928 |archive-date=2013-01-26 |access-date=2008-09-29}}</ref>

The [[Falcon 1]] launch that carried Ratsat to orbit was the first successful [[geocentric orbit|orbital]] launch of any [[private spaceflight|privately funded and developed]], [[Liquid-propellant rocket|liquid-propellant]] [[Launch vehicle|carrier rocket]], the [[SpaceX]] [[Falcon 1]], something only six nations had successfully accomplished previously.<ref name=sfn20080928/>

The launch, identified as ''Falcon 1 Flight 4'', was conducted by SpaceX, and also marked the first time the Falcon 1 rocket successfully achieved orbit, after three consecutive failures on the three previous launch attempts.<ref name="F3">{{cite web|url=http://www.space.com/news/080806-spacex-falcon1-update.html|title=SpaceX Traces Third Rocket Failure to Timing Error|last=Malik|first=Tariq|author2=Berger, Brian|date=2008-08-06|publisher=[[Space.com]]|access-date=2008-09-28|archive-date=2008-09-25|archive-url=https://web.archive.org/web/20080925124526/http://www.space.com/news/080806-spacex-falcon1-update.html|url-status=live}}</ref>

== Background ==
Prior to Ratsat's launch, three consecutive flights of the [[Falcon 1]] rocket had ended in failure. In particular, during the [[Falcon 1#Third flight|third launch]] of the Falcon 1 in August 2008, the first stage of the rocket after stage separation exhibited residual thrust and slammed into its second stage, resulting in catastrophic damage to the second stage's [[SpaceX Kestrel|Kestrel engine]].<ref name=":0" />{{Rp|page=|pages=177-179}}<ref name="F3" /> Though the fix for the problem was simple – add a time delay between main engine cut off and stage separation – SpaceX was running out of money and there was much uncertainty as to whether or not there would be a fourth flight for the company.<ref name=":0" />{{Rp|page=|pages=178-179}} SpaceX's CEO, [[Elon Musk]], was under immense stress financially and personally, as both of his ventures, SpaceX and [[Tesla, Inc.|Tesla Inc.]], were at risk of bankruptcy due to a series of failures. Compounding his financial stress was his recent divorce with [[Justine Musk]] - the resulting [[Division of property|property settlement]] left him homeless, as well as having lost their first son due to [[SIDS]].<ref name=":0" />{{Rp|page=|pages=182-183}}

== Preparation ==

=== Shipping to Omelek ===
Right after the third launch failure, Musk made an encouraging speech for the SpaceX employees and told them to launch another rocket in six weeks. According to Musk, this tight schedule was necessary or else the company would be overrun by operational fundings and at risk being in bankruptcy. The rocket was hastily built out of rocket spare parts in the factory.<ref name=":0" />{{Rp|page=183|pages=}}

The fourth launch of the Falcon 1 was supposed to deliver the Malaysian government's [[RazakSAT]] satellite, but the Malaysian government has backed out and no other customer was willing to launch on a thrice-failed rocket. Therefore, the SpaceX team had to make a non-functional aluminum [[Boilerplate (spaceflight)|boilerplate]] to simulate the rocket's payload. The boilerplate weighed {{Cvt|364|lb|kg|order=flip}} and was named "RatSat" after the last names of Jeff Richichi, Ray Amador and [[Chris Thompson (engineer)|Chris Thompson]], who were part of the company's structures team. The design for RatSat's logo was inspired by [[Ed Roth]] t-shirts, whom Thompson admired.<ref name=":0" />{{Rp|pages=183-184}}
Normally, Falcon 1's first stage would have been shipped by container to [[Omelek Island]], [[Kwajalein Atoll]], U.S. (where SpaceX launched the rocket) and Falcon 1's second stage would fly out to the island using the [[Douglas DC-8]] aircraft. The first stage was too big to be flown out using a DC-8. However, the tight schedule mandated the first stage to be shipped over air, so after scrambling with military contacts, a SpaceX employee was able to book a flight on the [[United States Air Force|U.S. Air Force]]'s [[Boeing C-17 Globemaster III]] with a price of $500,000. Being much larger than the DC-8, the C-17 can easily fit the rocket's first stage (which its [[dry mass]] weighs {{Cvt|4000|lb|kg|order=flip}} compared to the C-17 carrying capacity of {{Cvt|170000|lb|kg|disp=or|order=flip}}) and twenty supporting employees.<ref name=":0" />{{Rp|pages=184-187}}[[File:RatSat journey.svg|alt=Flight journey: Los Angeles International Airport, Hickam Air Force Base Hawaii, Omelek Island Kwajalein Atoll|left|thumb|Falcon 1's journey through the [[Pacific Ocean]]]]On 3 September, the C-17 landed at the [[Los Angeles International Airport]] near SpaceX's headquarters, loaded up, and took off without issues. An intentional small opening in the Falcon 1's oxygen tank fuel pressurization line was made to equalize the rocket's internal pressure with the surroundings. This approach worked well enough for the rocket tanks to slowly release its pressure while the plane was ascending. However, when it was time for the plane to descend to [[Hawaii]] and the cabin depressurized, the small opening did not allow air to pass into the rocket tanks fast enough. Thus, the Falcon 1 imploded, right next to the supporting crew. Had SpaceX crews not been onboard the flight, the Falcon 1 would have been ditched into the sea.<ref name=":0" />{{Rp|pages=183-189}}

With only 30 minutes of fuel left and the rocket continuing to crumble, the crew cut the [[Shrink wrap|shrink wraps]] with their knives and set to work fixing the problem. A member of the crew crawled inside the Falcon 1's [[interstage]] with a wrench and detached a pressurization line inside, allowing air to pass inside. The crumbling oxygen tank was inflated back to shape, though it had sustained damage to its structure. The C-17 landed at the [[Hickam Air Force Base]], Hawaii at midnight. The next morning, the crew and rocket took off from Hawaii and landed on an airstrip in the Kwajalein Atoll. A barge then carried the first stage of the rocket to Omelek Island.<ref name=":0" />{{Rp|pages=188-192}}

=== Rocket fixes and tests ===
Using a [[borescope]], a [[slosh baffle]] was found detached from the tank body, and it was clear that the Falcon 1 needed a total disassembly. A 'proper' six-week long fixing procedure was proposed, but it was promptly rejected because by then, operational expenses would cause SpaceX to not have any funds left. Another solution suggesting shipping back the rocket to the headquarters was also not viable for the same reason. The only viable option was to disassemble the rocket on the island itself, within one week. After some hesitancy, the SpaceX team got to work. On September 5, Falcon 1's engine was removed first, by removing connectors and fuel lines and placing the engine on the wood block. After one and a half days, the entire first stage was completely disassembled.<ref name=":0" />{{Rp|pages=192-196}}

While engineers at Omelek were working on the first stage, Thompson and Buzza (another engineer) flew back to Hawthorne on a [[Dassault Falcon 900]]. They loaded the plane with essential hardware and [[Triethylaluminium|TEA]]-[[Triethylborane|TEB]] ignition fluid, which is a substance that spontaneously combusts when in contact with air and for safety reasons is usually shipped by boat. Once touched down on the Kwajalein Atoll airstrip, they were told to leave the airplane until the next morning when the military crews would be available to unload supplies. Instead, Thompson and Buzza loaded the supplies on a truck and drove it to the barge dock, where they will be transported to Omelek. Now with Thompson and Buzza on-site, the SpaceX engineers reassembled the first stage and performed a wet dress rehearsal with liquid oxygen. There were concerns that the wrinkles on the first stage might cause a catastrophic explosion, but fortunately they were straightened out when the first stage was pressurized. To quote from [[Eric Berger (journalist)|Eric Berger]]'s ''Liftoff'': "They had broken virtually every rule in aerospace to pull the first stage together".<ref name=":0" />{{Rp|pages=193-196}}

The now-repaired first stage was reconnected with the first stage engine, and the rocket performed a [[static fire test]] on 20 September. Launch preparations on 23 September led the ground crew to replace part of a pipeline supplying [[liquid oxygen]] to the second stage [[Kestrel (rocket engine)|Kestrel]] engine. This work delayed the launch to 28 September.<ref>{{Cite web |author1=Brian Berger |date=2008-09-23 |title=SpaceX Pushes Back Falcon 1 Launch After Static Fire Test |url=https://www.space.com/5881-spacex-pushes-falcon-1-launch-static-fire-test.html |access-date=2024-03-10 |website=Space.com |language=en}}</ref><ref name="SpaceX updates2">{{cite web |last=Musk |first=Elon |date=2008-09-27 |title=Falcon 1 Flight 4 |url=http://www.spacex.com/F1-004.php |url-status=dead |archive-url=https://web.archive.org/web/20110725225434/http://www.spacex.com/F1-004.php |archive-date=2011-07-25 |access-date=2008-09-28 |publisher=[[SpaceX]]}}</ref>

==Launch==
[[File:Falcon 1 Flight 4 launch.jpg|thumb|Launch of RatSat on Falcon 1's fourth flight]]Falcon 1's flight four followed the same trajectory as the previous flight. No major changes were made to the rocket, other than increasing the time between first stage burnout and second stage separation. This minor change addressed the failure seen on the previous flight, recontact between the first and second stages, by dissipating residual thrust in the enhanced first stage engine in vacuum before [[separation event|separation]].<ref name="F3" /><ref name="SFN preview" /><ref>{{Cite news |last=Schwartz |first=John |date=2008-09-29 |title=Private Company Launches Its Rocket Into Orbit |url=https://www.nytimes.com/2008/09/29/science/space/29launch.html?_r=1&ref=us&oref=slogin |url-status=live |archive-url=https://web.archive.org/web/20171214130057/http://www.nytimes.com/2008/09/29/science/space/29launch.html?_r=1&ref=us&oref=slogin |archive-date=2017-12-14 |access-date=2008-09-29 |work=[[The New York Times]] |issn=0362-4331}}</ref>{{Wikinews|SpaceX rocket successfully orbits on fourth attempt}}

Liftoff occurred from [[Omelek Island]] at 23:15&nbsp;UTC on 28 September, 15 minutes into a five-hour launch window. If the launch had been scrubbed, it could have been conducted during the same window until 1 October.<ref name="SpaceX updates">{{cite web |last=Musk |first=Elon |date=2008-09-27 |title=Falcon 1 Flight 4 |url=http://www.spacex.com/F1-004.php |url-status=dead |archive-url=https://web.archive.org/web/20110725225434/http://www.spacex.com/F1-004.php |archive-date=2011-07-25 |access-date=2008-09-28 |publisher=[[SpaceX]]}}</ref> Nine minutes and 31 seconds after launch, the second stage engine shut down, after the vehicle reached orbit.<ref name="MSC">{{cite web |last=Ray |first=Justin |date=2008-09-28 |title=Mission Status Center |url=http://www.spaceflightnow.com/falcon/004/status.html |url-status=live |archive-url=https://web.archive.org/web/20120511030554/http://spaceflightnow.com/falcon/004/status.html |archive-date=2012-05-11 |access-date=2008-09-28 |publisher=Spaceflight Now}}</ref> The initial orbit was reported to be approximately {{convert|330|x|650|km}}.<ref name="sfn20080928">{{cite web |last=Clark |first=Stephen |title=Sweet Success at Last for Falcon 1 Rocket |date=2008-09-28 |publisher=Spaceflight Now |url=http://www.spaceflightnow.com/falcon/004/index.html |access-date=2011-04-06 |quote=''the first privately developed liquid-fueled rocket to successfully reach orbit.'' |archive-date=2019-05-28 |archive-url=https://web.archive.org/web/20190528181034/https://spaceflightnow.com/falcon/004/index.html |url-status=live }}</ref> Following a coast period, the second stage restarted, and performed a successful second burn, resulting in a final orbit of {{convert|621|x|643|km}} at 9.35° [[orbital inclination|inclination]].<ref name="JSR 601" />

== Aftermath ==
The launch of RatSat marked the first successful orbital launch of any [[private spaceflight|privately funded and developed]], [[Liquid-propellant rocket|liquid-propellant]] [[Launch vehicle|carrier rocket]].<ref name="sfn20080928" /> After a short three-minutes speech by Musk,<ref>{{Cite AV media |url=https://www.youtube.com/watch?v=8FQhtMrUQlE |title=SpaceX reaches orbit with Falcon 1 - Flight 4 (full video including Elon Musk statement) |date=Sep 29, 2008 |type=Webcast |publisher=Spacevidcast |time=32:40–36:07}}</ref> SpaceX employees partied at Tavern on Main and Purple Orchid, two bars that are close to SpaceX's headquarters. For the employees at the mission control room at Kwajalein, they monitored RatSat until the second stage's battery ran out of power. They locked the mission control room and biked towards the dock, where they waited for the backup crew from Meck island and celebrated at a local bar.<ref name=":0" />{{Rp|pages=207-213}}

Even though SpaceX finally has achieved a successful orbital flight, Musk only has $30 million left and was unable to support both SpaceX and Tesla for two months. Contrary to popular belief, Falcon 1's flight 4 did not directly lead to more customer contracts. Through 2008, SpaceX launch manifest at the time only consisted of [[RazakSAT]]. Rather, it was NASA's [[Commercial Orbital Transportation Services]] and subsequent [[Commercial Resupply Services]] contracts that provided SpaceX much-needed fund to save it from bankruptcy.<ref name=":0" />{{Rp|pages=217}}

Although SpaceX was working on concepts to recover the first stage of Falcon 1 using parachutes, they had not yet succeeded in doing so. Falcon 1 was subsequently retired from service after its fifth launch, with first stage recovery never having been accomplished successfully. The first stage of the successor rocket, the [[Falcon 9]], would eventually fulfill and prove the viability of booster stage recovery.

==See also==
* [[2008 in spaceflight]]

==References==
{{Reflist|30em}}

== External links ==
* Photo section, page i-1 – i-16, at {{Cite book |last=Berger |first=Eric |url= |title=Liftoff: Elon Musk and the Desperate Early Days That Launched SpaceX |date=March 2, 2021 |publisher=[[William Morrow and Company]] |isbn=978-0-00-844562-1 |location=London |oclc=1233312066 |author-link=Eric Berger (meteorologist)}}
* [https://www.youtube.com/watch?v=8FQhtMrUQlE SpaceX reaches orbit with Falcon 1 - Flight 4 (full video including Elon Musk statement)] – TMRO's contemporary webcast

{{Falcon rocket launches}}
{{Orbital launches in 2008}}

[[Category:Spacecraft launched by Falcon rockets]]
[[Category:Derelict satellites orbiting Earth]]
[[Category:Spacecraft launched in 2008]]
[[Category:Test spaceflights]]