Falcon 9 full thrust

Falcon 9 full thrust

Launch of the first Falcon 9 full thrust flight, Falcon 9 Flight 20, carrying 11 Orbcomm satellites to orbit. The first stage was recovered at Cape Canaveral Air Force Station LZ-1 following the first successful Falcon 9 landing.
Function	Orbital launch vehicle
Manufacturer	SpaceX
Country of origin	United States[1]
Cost per launch	$61.2M[2]
Size
Height	70 m (230 ft) with payload fairing[3]
Diameter	3.66 m (12.0 ft)[1]
Mass	541,300 kg (1,193,400 lb)[1]
Stages	2[1]
Capacity
Payload to LEO	13,150 kg (28,990 lb)[2][1]
Payload to GTO	At least 5,300 kg (11,700 lb)[4][5]
Launch history
Status	Active
Launch sites	Cape Canaveral SLC-40 Vandenberg SLC-4E[2]
Total launches	1
Successes	1
First flight	Orbcomm OG2 Flight 2
First stage
Engines	9 Merlin 1D[1]
Thrust	6,806 kN (1,530,000 lbf)[1]
Specific impulse	Sea level: 282 s[6] Vacuum: 311 s[7]
Burn time	162 seconds[1]
Fuel	subcooled LOX/chilled RP-1[8]
Second stage
Engines	Merlin Vacuum (1D)[1]
Thrust	934 kN (210,000 lbf)[9]
Specific impulse	Vacuum: 348 s[1]
Burn time	397 seconds[1]
Fuel	LOX/RP-1

Falcon 9 full thrust—also known as Falcon 9 v1.1 Full Thrust, and earlier as Falcon 9 v1.2, Enhanced Falcon 9, Full-Performance Falcon 9, Upgraded Falcon 9, and Falcon 9 Upgrade—is the third major version of the SpaceX Falcon 9 orbital launch vehicle. Designed in 2014–2015, it began launch operations in December 2015, and has a large manifest of over 40 launches contracted over the next five years.

In December 2015, the full thrust version of the Falcon 9 was the first launch vehicle on an orbital trajectory to successfully vertically-land a first stage and recover the rocket, following an extensive technology development program in 2011–2015 that had developed some of the technology on Falcon 9 v1.0 and Falcon 9 v1.1 launch vehicle first stages.

Falcon 9 full thrust is a substantial upgrade over the older Falcon 9 v1.1 rocket, which flew its last mission in January 2016. With uprated first- and second-stage engines, larger second-stage propellant tankage, and propellant densification, the vehicle can carry substantial payload to geostationary orbit and perform a propulsive landing for recovery.^[10]

History

As early as March 2014, SpaceX pricing and payload specifications published for the non-reusable Falcon 9 v1.1 rocket actually included about 30 percent more performance than the published price list indicated. At that time, the additional performance was reserved for SpaceX to do reusability testing with the Falcon 9 v1.1 while still achieving the specified payloads for customers. Many engineering changes to support reusability and recovery of the first stage had been made on this earlier v1.1 version. SpaceX indicated they had room to increase the payload performance for the Falcon 9 v1.1 full thrust, or decrease launch price, or both.^[11]

In 2015, SpaceX announced a number of modifications to the previous version Falcon 9 v1.1 launch vehicle. The new rocket was known internally for a while as Falcon 9 v1.1 Full Thrust,^[12] but was also known under a variety of names including Falcon 9 v1.2, Enhanced Falcon 9, Full-Performance Falcon 9,^[13] Upgraded Falcon 9,^[14] and Falcon 9 Upgrade.^[15][16] Since the first flight in late 2015, SpaceX has been referring to the "full thrust upgrade" Falcon 9 merely as Falcon 9.^[17] However, it is in fact the third major version of the Falcon 9 launch vehicle following the Falcon 9 v1.0 (launched 2010–2013) and the Falcon 9 v1.1 (launched 2013–January 2016). The Falcon 9 full thrust was first launched on 22 December 2015, on the 20th Falcon 9 flight.^[14]

SpaceX President Gwynne Shotwell explained in March 2015 that the new design would result in streamlined production as well as improved performance:^[18]

So, we got the higher thrust engines, finished development on that, we're in [qualification testing]. What we're also doing is modifying the structure a little bit. I want to be building only two versions, or two cores in my factory, any more than that would not be great from a customer perspective. It's about a 30% increase in performance, maybe a little more. What it does is it allows us to land the first stage for GTO missions on the drone ship.^[13]

According to a SpaceX statement in May 2015, Falcon 9 full thrust would likely not require a recertification to launch for United States government contracts. Shotwell stated that "It is an iterative process [with the agencies]" and that "It will become quicker and quicker to certify new versions of the vehicle."^[19]

SES S.A., a satellite owner and operator, announced plans in February 2015 to launch its SES-9 satellite on the first flight of the Falcon 9 full thrust.^[20] In the event, SpaceX elected to launch SES-9 on the second flight of the Falcon 9 full thrust and to launch Orbcomm OG2's second constellation on the first flight. As Chris Bergin of NASASpaceFlight explained, SES-9 required a more complicated second-stage burn profile involving one restart of the second-stage engine, while the Orbcomm mission would "allow for the Second Stage to conduct additional testing ahead of the more taxing SES-9 mission."^[21]

The upgraded first stage began acceptance testing at SpaceX's McGregor facility in September 2015. The first of two static fire tests was completed on 21 September 2015 and included the supercooled propellant and the improved Merlin 1D engines.^[22] The rocket reached full throttle during the static fire and was scheduled for launch no earlier than 17 November 2015.^[23]

Falcon 9 Full Thrust completed its maiden flight on 22 December 2015, carrying an Orbcomm 11-satellite payload to orbit and landing the rocket's first stage intact at SpaceX's Landing Zone 1 at Cape Canaveral.^[14] The second mission, SES-9, is planned for no earlier than 6 February 2016.

The US Air Force certified the upgraded version of the launch vehicle to be used on US military launches in January 2016, based on the one successful launch to date and the demonstrated "capability to design, produce, qualify, and deliver a new launch system and provide the mission assurance support required to deliver NSS (national security space) satellites to orbit".^[9]

Design

A principal objective of the new design was to facilitate booster reusability for a larger range of missions, including delivery of large commsats to geosynchronous orbit.^[24]

Modifications in the upgraded version, relative to the previous version (Falcon 9 v1.1) include:

• liquid oxygen subcooled to −340 °F (−210 °C; 66 K) and RP-1 cooled to 20 °F (−6.7 °C; 270 K)^[25] for density (allowing more fuel and oxidizer to be stored in a given tank volume, as well as increasing the propellant mass flow through the turbopumps increasing thrust)^[9]
• upgraded structure in the first stage^[15][26]
• longer second stage propellant tanks^[15]
• longer and stronger interstage, housing the second stage engine nozzle, grid fins, and attitude thrusters^[15][26]
• overall launch vehicle length (with payload fairing) is now 70 m (229 ft), about 1.5 m (5 ft) taller than Falcon 9 v1.1^[9]
• pneumatic center pusher added to stage separation mechanism.^[15] Designed to provide redundant "positive-force stage separation after latch release ... for added reliability ... to dramatically decrease the probability of re-contact between the stages following separation."^[27]
• design evolution of the grid fins^[15][26]
• modified Octaweb engine thrust structure^[15]
• upgraded landing legs^[15][26]
• Merlin 1D engine thrust increased^[15] to the full-thrust variant of the Merlin 1D, taking advantage of the denser propellants achieved by subcooling. First stage thrust is now 6,700 kN (1,500,000 lb_f) rather than 5,800 kN (1,300,000 lb_f) on the Falcon 9 v1.1.^[9]
• Merlin 1D vacuum thrust increased by subcooling the propellants.^[15] The new second-stage engine was optimized for higher performance in vacuum through modifications such as a larger exhaust nozzle and an improved attitude control system.^[28][29] Second stage thrust is now 930 kN (210,000 lb_f).^[9]
• several small mass-reduction efforts.^[30]

The modified design gained an additional 1.5 meters of height,^[9] stretching to exactly 70 meters including payload fairing when fairings are used (the Dragon capsule version is somewhat shorter),^[27] while gaining an overall performance increase of 33 percent.^[15] The new first-stage engine has a much increased thrust-to-weight ratio.^[29]

Like earlier versions of the Falcon 9, and like the Saturn series from the Apollo program, the presence of multiple first-stage engines can allow for mission completion even if one of the first-stage engines fails mid-flight.^[27]

The full-thrust first stage booster could reach low Earth orbit as a single-stage-to-orbit vehicle if it is not carrying the upper stage and a heavy satellite.^[31]

According to Musk, Falcon 9 can send 3-4 tons to Mars.^[32]

Vehicle description

Falcon 9 full thrust specifications and characteristics are as follows:^[27]

The full thrust Falcon 9 uses an interstage that is longer and stronger than the Falcon 9 v1.1 interstage. It is a "composite structure consisting of an aluminum honeycomb core surrounded by a carbon fiber face sheet plies."^[27]

The full thrust Falcon 9 upgraded vehicle "includes first-stage recovery systems, to allow SpaceX to return the first stage to the launch site after completion of primary mission requirements. These systems include four deployable landing legs, which are locked against the first-stage tank during ascent. Excess propellant reserved for Falcon 9 first-stage recovery operations will be diverted for use on the primary mission objective, if required, ensuring sufficient performance margins for successful missions."^[27]

Launch and landing sites

Launch sites

SpaceX is using both Launch Complex 40 at Cape Canaveral Air Force Station and Launch Complex 4E at Vandenberg Air Force Base for launching Falcon 9 full thrust rockets, like its predecessor Falcon 9 v1.1.

SpaceX has "activated" an additional launch site in Florida for crewed Falcon 9 missions and all Florida Falcon Heavy missions at Launch Complex 39 leased from NASA at Kennedy Space Center.^[33] Architectural and engineering design work on the pad modifications began in 2013, the contract to lease the pad from NASA was signed in April 2014, with construction commencing later in 2014,^[34] including the building of a large Horizontal Integration Facility (HIF) in order to house both Falcon 9 and Falcon Heavy launch vehicles with associated hardware and payloads during processing.^[35] While "activated" indicates it is ready for launches of the Falcon Heavy rocket and also the Falcon 9, it has not yet been used by SpaceX and the first launch from that location is expected in 2016. Some more work may still be needed before crewed launches.

An additional private launch site, intended solely for commercial launches, is currently under construction near Brownsville, Texas^[36] following a multi-state evaluation process in 2012–mid-2014 looking at Florida, Georgia, and Puerto Rico.^[37][38]

Landing Sites

SpaceX has completed construction of a landing zone at Cape Canaveral Air Force Station, known as LZ-1. The zone, consisting of a pad 282 feet (86 m) in diameter, was first used on 16 December 2015 with a successful landing of Falcon 9 full thrust.^[39] The landing on LZ-1 was the first overall successful Falcon 9 and the third landing attempt on a hard surface.

References