RatSat
Mission type | Launch demonstration |
---|---|
Operator | SpaceX |
COSPAR ID | 2008-048A |
SATCAT no. | 33393 |
Mission duration | 15 years, 6 months, 23 days (in orbit) |
Spacecraft properties | |
Manufacturer | SpaceX |
Launch mass | 165 kg (364 lb)[1] |
Dimensions | 1.5 m (4.9 ft) in length |
Start of mission | |
Launch date | 28 September 2008, 23:15 | UTC
Rocket | Falcon 1 |
Launch site | Omelek Island |
Contractor | SpaceX |
Orbital parameters | |
Regime | Low Earth orbit |
Perigee altitude | 617 kilometers (383 mi)[2] |
Apogee altitude | 635 kilometers (395 mi)[2] |
Inclination | 9.35°[2] |
Period | 97.09 minutes[2] |
Epoch | 24 January 2015, 18:58:23 UTC[2] |
RatSat[1]: 184 or DemoSat[3] was an aluminum mass simulator on the fourth flight of the Falcon 1 rocket, launched on 28 September 2008. Ratsat[4] remained bolted to the second stage of the carrier rocket after reaching low Earth orbit.[5] It is an aluminium alloy chamber in hexagonal prism shape with 1.5 m (5 ft) length.[6]
The Falcon 1 launch that carried Ratsat to orbit was the first successful orbital launch of any privately funded and developed, liquid-propellant carrier rocket, the SpaceX Falcon 1, something only six nations had successfully accomplished previously.[7]
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.[8]
Background
Prior to Ratsat's launch, three consecutive flights of the Falcon 1 rocket had ended in failure. In particular, during the 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 Kestrel engine.[1]: 177–179 [8] 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.[1]: 178–179 SpaceX's CEO, Elon Musk, was under immense stress financially and personally, as both of his ventures, SpaceX and 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 property settlement left him homeless, as well as having lost their first son due to SIDS.[1]: 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 overran by operational fundings and at risk being in bankruptcy. The rocket was hastily built out of rocket spare parts in the factory.[1]: 183
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 to simulate the rocket's payload. The boilerplate weighed 165 kg (364 lb) and was named "RatSat" after the last names of Jeff Richichi, Ray Amador and 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.[1]: 183–184
Normally, Falcon 1's first stage would have been shipped by container to
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.[1]
With only 30 minutes of fuel left and the rocket continuing to crumble, the crew cut the
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-weeks 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 day, the entire first stage was completely disassembled.[1]: 192–196
While engineers at Omelek were working on the first stage, Thompson and Buzza (another engineer) flew back to Hawthorne on a
The now-repaired first stage was reconnected with the first stage, and the rocket performed a
Launch
Liftoff occurred from Omelek Island at 23:15 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.[12] Nine minutes and 31 seconds after launch, the second stage engine shut down, after the vehicle reached orbit.[13] The initial orbit was reported to be approximately 330 by 650 kilometres (210 mi × 400 mi).[7] Following a coast period, the second stage restarted, and performed a successful second burn, resulting in a final orbit of 621 by 643 kilometres (386 mi × 400 mi) at 9.35° inclination.[4]
Aftermath
The launch of RatSat marked the first successful orbital launch of any privately funded and developed, liquid-propellant carrier rocket.[7] After a short three-minutes speech by Musk,[14] 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.[1]: 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 led 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.[1]: 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
References
- ^ OCLC 1233312066.
- ^ a b c d e "DEMOSAT/FALCON 1 Satellite details 2008-048A NORAD 33393". N2YO. 24 January 2015. Archived from the original on 22 September 2015. Retrieved 25 January 2015.
- ^ "DemoSat, NSSDC ID: 2008-048A". NASA NSSDC. 2008-09-28. Archived from the original on 2020-10-24. Retrieved 2012-08-24.
- ^ a b McDowell, Jonathan (2008-09-26). "Issue 601". Jonathan's Space Report. Archived from the original on 2009-08-26. Retrieved 2008-09-29.
- ^ a b Clark, Stephen (2008-09-27). "SpaceX to launch its fourth Falcon 1 rocket on Sunday". Spaceflight Now. Archived from the original on 2008-12-19. Retrieved 2008-09-28.
- ^ "Press Release: SpaceX Successfully Launches Falcon 1 to Orbit". Archived from the original on 2013-01-26. Retrieved 2008-09-29.
- ^ a b c Clark, Stephen (2008-09-28). "Sweet Success at Last for Falcon 1 Rocket". Spaceflight Now. Archived from the original on 2019-05-28. Retrieved 2011-04-06.
the first privately developed liquid-fueled rocket to successfully reach orbit.
- ^ a b c Malik, Tariq; Berger, Brian (2008-08-06). "SpaceX Traces Third Rocket Failure to Timing Error". Space.com. Archived from the original on 2008-09-25. Retrieved 2008-09-28.
- ^ published, Brian Berger (2008-09-23). "SpaceX Pushes Back Falcon 1 Launch After Static Fire Test". Space.com. Retrieved 2024-03-10.
- ^ Musk, Elon (2008-09-27). "Falcon 1 Flight 4". SpaceX. Archived from the original on 2011-07-25. Retrieved 2008-09-28.
- from the original on 2017-12-14. Retrieved 2008-09-29.
- ^ Musk, Elon (2008-09-27). "Falcon 1 Flight 4". SpaceX. Archived from the original on 2011-07-25. Retrieved 2008-09-28.
- ^ Ray, Justin (2008-09-28). "Mission Status Center". Spaceflight Now. Archived from the original on 2012-05-11. Retrieved 2008-09-28.
- ^ SpaceX reaches orbit with Falcon 1 - Flight 4 (full video including Elon Musk statement) (Webcast). Spacevidcast. Sep 29, 2008. Event occurs at 32:40–36:07.
External links
- Photo section, page i-1 – i-16, at OCLC 1233312066.
- SpaceX reaches orbit with Falcon 1 - Flight 4 (full video including Elon Musk statement) – TMRO's contemporary webcast