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Tuesday, December 24, 2019

New Shepard

From Wikipedia, the free encyclopedia
https://en.wikipedia.org/wiki/New_Shepard
 
New Shepard
New Shephard - Upright View.jpg
New Shepard 2 at the 2017 EAA AirVenture
FunctionSuborbital launch vehicle
ManufacturerBlue Origin
Country of originUnited States
Size
Height18 m (59 ft)
Stages1
Launch history
Statusactive
Launch sitesCorn Ranch
Total launches12
Successes12
Landings11
First flight29 April 2015
Last flightActive

First stage
Engines1 BE-3
Thrust490 kN (110,000 lbf)
Burn time110 seconds
FuelLH2 / LOX

New Shepard is a vertical-takeoff, vertical-landing (VTVL), human-rated suborbital rocket that is being developed by Blue Origin as a commercial system for suborbital space tourism. Blue Origin is owned and led by Amazon.com founder and businessman Jeff Bezos and aerospace engineer Rob Meyerson. NASA Silver Snoopy Award winner Robert Smith is the company's chief executive officer.

The name New Shepard makes reference to the first American astronaut in space, Alan Shepard, one of the original NASA Mercury Seven astronauts, who ascended to space on a suborbital trajectory similar to that planned for New Shepard.

Prototype engine and vehicle flights began in 2006, while full-scale engine development started in the early 2010s and was complete by 2015. Uncrewed flight testing of the complete New Shepard vehicle (propulsion module and space capsule) began in 2015.

On 23 November 2015, after reaching 100.5 km (62.4 mi) altitude (outer space), the suborbital New Shepard booster successfully performed a powered vertical soft landing, the first time a suborbital booster rocket had returned from space to make a successful vertical landing. The test program continued in 2016 and 2017 with four additional test flights made with the same vehicle (NS2) in 2016 and the first test flight of the new NS3 vehicle made in 2017.

Blue Origin is planning the first crewed test flight to occur in 2019, and has announced that tickets would begin to be sold for commercial flights.

History


Early Blue Origin vehicle and engine development

The first development vehicle of the New Shepard development program was a sub-scale demonstration vehicle named Goddard, built in 2006 following earlier engine development efforts by Blue Origin. Goddard made its first flight on 13 November 2006.

The Goddard launch vehicle was assembled at the Blue Origin facility near Seattle, Washington. Also in 2006, Blue Origin started the process to build an aerospace testing and operations center on a portion of the Corn Ranch, a 165,000-acre (668 km2) land parcel Bezos purchased 40 kilometers (25 mi) north of Van Horn, Texas. Blue Origin Project Manager Rob Meyerson has said that they selected Texas as the launch site particularly because of the state's historical connections to the aerospace industry, although that industry is not located near the planned launch site, and the vehicle will not be manufactured in Texas.

On the path to developing New Shepard, a crew capsule was also needed, and design was begun on a space capsule in the early 2000s. One development milestone along the way became public. On 19 October 2012, Blue Origin conducted a successful Pad Escape a full-scale suborbital Crew Capsule at its West Texas launch site. For the test, the capsule fired its pusher escape motor and launched from a launch vehicle simulator. The Crew Capsule traveled to an altitude of 2,307 ft (703 m) under active thrust vector control before descending safely by parachute to a soft landing 1,630 ft (500 m) downrange.

In April 2015, Blue Origin announced that they had completed acceptance testing of the BE-3 engine that would power the larger New Shepard vehicle. Blue also announced that they intended to begin flight testing of the New Shepard later in 2015, with initial flights occurring as frequently as monthly, with "a series of dozens of flights over the extent of the suborbital test program [taking] a couple of years to complete." The same month, the FAA announced that the regulatory paperwork for the test program had already been filed and approved, and test flights were expected to begin before mid-May 2015.

By February 2016, three New Shepard vehicles had been built. The first was lost in a test in April 2015, the second had flown twice (see below), and the third was completing manufacture at the Blue factory in Kent, Washington. 

Flight test program

A multi-year program of flight tests was begun in 2015 and is continuing in 2018. By mid-2016, the test program was sufficiently advanced that Blue Origin has begun flying suborbital research payloads for universities and NASA.

Flight № Date Vehicle Outcome Notes
1 29 April 2015 New Shepard 1 Partial success Flight to altitude 93.5 km, capsule recovered, booster crashed on landing
2 23 November 2015 New Shepard 2 Success Sub-orbital spaceflight and landing
3 22 January 2016 New Shepard 2 Success Sub-orbital spaceflight and landing of a reused booster
4 2 April 2016 New Shepard 2 Success Sub-orbital spaceflight and landing of a reused booster
5 19 June 2016 New Shepard 2 Success Sub-orbital spaceflight and landing of a reused booster: The fourth launch and landing of the same rocket. Blue Origin published a live webcast of the takeoff and landing.
6 5 October 2016 New Shepard 2 Success Sub-orbital spaceflight and landing of a reused booster. Successful test of the in-flight abort system. The fifth and final launch and landing of the same rocket (NS2).
7 12 December 2017 New Shepard 3 Success Flight to just under 100 km and landing. The first launch of NS3 and a new Crew Capsule 2.0.
8 29 April 2018 New Shepard 3 Success Sub-orbital spaceflight and landing of a reused booster. Apogee 351,000 feet (approx 107 km).
9 18 July 2018 New Shepard 3 Success Sub-orbital spaceflight and landing of a reused booster, with the Crew Capsule 2.0-1 RSS H.G.Wells, carrying a mannequin. Successful test of the in-flight abort system at high altitude. Apogee 389,846 feet (73.8 mi; 119 km), duration 11 minutes.
10 23 January 2019 New Shepard 3 Success Sub-orbital flight, delayed from 18 December 2018. Eight NASA research and technology payloads were flown. Apogee: 106.9 km (351,000 ft)
11 2 May 2019 New Shepard 3 Success Sub-orbital flight. Apogee 106 km (348,000 ft), Max Ascent Velocity: 2,217 mph (3,568 km/h), duration: 10 minutes, 10 seconds. Payload: 38 microgravity research payloads (nine sponsored by NASA).
12 11 December 2019 New Shepard 3 Success Sub-orbital flight, apogee 104.5 kilometers. Payload: Multiple commercial, research (8 sponsored by NASA) and educational payloads, including postcards from Club for the Future.

New Shepard 1

NS1 launch in April 2015
 
The first flight of the full-scale New Shepard vehicle—NS1—was conducted on 29 April 2015 during which an altitude of 93.5 km (307,000 ft) was attained. While the test flight itself was deemed a success, and the capsule was successfully recovered via parachute landing, the booster stage crashed on landing and was not recovered due to a failure of hydraulic pressure in the vehicle control system during the descent.

New Shepard 2

The New Shepard 2, or NS2, flight test article propulsion module made five successful flights in 2015 and 2016, being retired after its fifth flight in October 2016.
First vertical soft landing
After the loss of NS1, a second New Shepard vehicle was built, NS2. Its first flight, and the second test flight of New Shepard overall, was carried out on 23 November 2015, reaching 100.5 km (330,000 ft) altitude with successful recovery of both capsule and booster stage. The booster rocket successfully performed a powered vertical landing. This was the first such successful rocket vertical landing on Earth after travelling higher than 3,140 m (10,300 ft) that the McDonnell Douglas DC-XA achieved in the 1990s, and first after sending something into space. Jeff Bezos was quoted as saying that Blue Origin planned to use the same architecture of New Shepard for the booster stage of their orbital vehicle.

Second vertical soft landing
On 22 January 2016, Blue Origin successfully repeated the flight profile of 23 November 2015 launch with the same New Shepard vehicle. New Shepard launched, reached a maximum altitude of 101.7 km (63.2 mi), and, after separation, both capsule and launch vehicle returned to the ground intact. This accomplishment demonstrated re-usability of New Shepard and a turnaround time of 61 days.

Third vertical soft landing
On 2 April 2016, the same New Shepard booster flew for a third time, reaching 339,178 feet (103.8 km), before returning successfully.

Fourth vertical soft landing
On 19 June 2016, the same New Shepard booster flew, now for a fourth time, again reaching over 330,000 feet (100.6km), before returning successfully for a VTVL rocket-powered landing.

The capsule returned once again under parachutes but, this time, did a test descent with only two parachutes before finishing with a brief pulse of retro rocket propulsion to slow the ground impact velocity to 4.8 km/h (3 mph). The two parachutes "slowed the descent to 23 mph, as opposed to the usual 16 mph with three parachutes". Crushable bumpers are used to further reduce the landing shock through energy-absorbing deformation.

Fifth and final flight test of NS2: October 2016
A fifth and final test flight of the NS2 propulsion module was conducted on 5 October 2016. The principal objective was to boost the passenger module to the point of highest dynamic pressure at transonic velocity and conduct a flight test of the in-flight abort system. Due to subsequent buffet and forces that impact the propulsion module after the high-velocity separation of the passenger capsule that are outside the design region of the PM, NS2 was not expected to survive and land, and if it did, Blue had stated that NS2 would be retired and become a museum item. In the event, the flight test was successful. The abort occurred, and NS2 remained stable after the capsule abort test, completed its ascent to space, and successfully landed for a fifth and final time.

New Shepard 3

New Shepard 3 (NS3) was modified for increased reusability and improved thermal protection; it includes a redesigned propulsion module and the inclusion of new access panels for more rapid servicing and improved thermal protection. NS3 is the third propulsion module built. It was completed and shipped to the launch site by September 2017, although parts of it had been built as early as March 2016. Flight tests began in 2017 and continued into 2019. The new Crew Capsule 2.0, featuring windows, is integrated to the NS3. NS3 will only ever be used to fly cargo; no passengers will be carried.

Its initial flight test occurred on 12 December 2017. This was the first flight flown under the regulatory regime of a launch license granted by the US Federal Aviation Administration. Previous test flights had flown under an experimental permit, which did not allow Blue to carry cargo for which it is paid for commercially. This made the flight of NS3 the first revenue flight for payloads, and it carried 12 experiments on the flight, as well as a test dummy given the moniker "Mannequin Skywalker."

Since the maiden flight, "Blue Origin has been making updates to the vehicle ... intended primarily to improve operability rather than performance or reliability. Those upgrades took longer than expected" leading to a several-month gap in test flights. The second test flight took place on 29 April 2018. The 10th overall New Shepard flight, and the fourth NS4 flight, had originally been planned for December 2018, but was delayed due to "ground infrastructure issues." Following a diagnostics of the initial issue, Blue rescheduled the launch for early 2019, after discovering "additional systems" that needed repairs as well. The flight launched on 23 January 2019 and successfully flew to space with a maximum altitude of 106.9 km.

New Shepard vehicles 2018+

New Shepard 4 (NS4)—the fourth propulsion module to be built—will be the first one to actually carry passengers. The vehicle was manufactured in 2018 and moved to the Texas Blue Origin West Texas launch facility by December. The maiden flight is expected in 2020.

Additional vehicles are under construction. An initial build order of six vehicles was planned, each one taking 9 to 12 months to construct. After the initial build, and after completing an extensive test flight program, Blue Origin intends to "let the demand for space tourism and research determine how many additional vehicles may be needed."

Commercial flight

For many years, Blue Origin did not make public statements about the date of the start of commercial flights of New Shepard. This changed in June 2018 when the company announced that while it continued to plan to fly initial internal passengers later in 2018, it would not be selling commercial tickets for New Shepard until 2019. As of December 2019, the company had yet to fly commercial passengers on the rocket. 

Design

The New Shepard is a fully reusable, vertical takeoff, vertical landing (VTVL) space vehicle composed of two principal parts: a pressurized crew capsule and a booster rocket that Blue Origin calls a propulsion module. The New Shepard is controlled entirely by on-board computers, without ground control or a human pilot.

Crew capsule

The New Shepard Crew Capsule is a pressurized crew capsule that can carry six people, and supports a "full-envelope" launch escape system that can separate the capsule from the booster rocket anywhere during the ascent. Interior volume of the capsule is 15 cubic meters (530 cu ft). The Crew Capsule Escape Solid Rocket Motor (CCE-SRM) is sourced from Aerojet Rocketdyne. After separation two or three parachutes deploy. Just before landing, retro rockets fire. (see Fourth vertical soft landing (19 June 2016) above) 

Propulsion module

The New Shepard propulsion module is powered using a Blue Origin BE-3 bipropellant rocket engine burning liquid hydrogen and liquid oxygen, although some early development work was done by Blue Origin on engines operating with other propellants: the BE-1 engine using monopropellant hydrogen peroxide; and the BE-2 engine using high-test peroxide oxidizer and RP-1 kerosene fuel.

Mission

The New Shepard is launched vertically from West Texas and then performs a powered flight for about 110 s and to an altitude of 40 km (130,000 ft). The craft's momentum carries it upward in unpowered flight as the vehicle slows, culminating at an altitude of about 100 km (330,000 ft). After reaching apogee the vehicle would perform a descent and restart its main engines a few tens of seconds before vertical landing, close to its launch site. The total mission duration is planned to be 10 minutes. 

The crewed variant would feature a separate crew module that could separate close to peak altitude, and the propulsion module would perform a powered landing while the crew module would land under parachutes. The crew module can also separate in case of vehicle malfunction or other emergency using solid propellant separation boosters and perform a parachute landing.

Development

Initial low altitude flight testing (up to 600 m) with subscale prototypes of the New Shepard was scheduled for the fourth quarter of 2006. This was later confirmed to have occurred in November 2006 in a press release by Blue Origin. The prototype flight test program could involve up to ten flights. Incremental flight testing to 100 km altitude was planned to be carried out between 2007 and 2009 with increasingly larger and more capable prototypes. The full-scale vehicle was initially expected to be operational for revenue service as early as 2010, though that goal was not met and the first full-scale test flight of a New Shepard vehicle was successfully completed 2015, with commercial service currently aimed for no earlier than 2018. The vehicle could fly up to 50 times a year. Clearance from the FAA was needed before test flights began, and a separate license is needed before commercial operations begin. Blue held a public meeting on 15 June 2006 in Van Horn, as part of the public comment opportunity needed to secure FAA permissions. Blue Origin projected in 2006 that once cleared for commercial operation, they would expect to conduct a maximum rate of 52 launches per year from West Texas. The RLV would carry three or more passengers per operation.

Prototype test vehicle

An initial flight test of a prototype vehicle took place on 13 November 2006 at 6:30 am local time (12:30 UTC); an earlier flight on the 10th being canceled due to winds. This marked the first developmental test flight undertaken by Blue Origin. The flight was by the first prototype vehicle, known as Goddard. The flight to 285 feet (87 m) in altitude was successful. Videos are available on the Blue Origin website and elsewhere.

Second test vehicle

A second test vehicle made two flights in 2011. The first flight was a short hop (low altitude, VTVL takeoff and landing mission) flown in approximately early June.

The vehicle is known only as "PM2" as of August 2011, gleaned from information the company filed with the FAA prior to its late August high-altitude, high-velocity second test flight. Media have speculated this might mean "Propulsion Module".

The second test vehicle was flown a second time on a 24 August 2011 test flight, in west Texas. It failed when ground personnel lost contact and control of the vehicle. The company recovered remnants of the space craft from ground search. On 2 September 2011, Blue Origin released the results of the cause of the test vehicle failure. As the vehicle reached Mach 1.2 and 45,000 feet (14,000 m) altitude, a "flight instability drove an angle of attack that triggered [the] range safety system to terminate thrust on the vehicle."

Involvement with NASA Commercial Crew Development Program

Additionally, Blue Origin received US$3.7 million in CCDev phase 1 to advance several development objectives of its innovative 'pusher' Launch Abort System (LAS) and composite pressure vessel As of February 2011, with the end of the second ground test, Blue Origin completed all work envisioned under the phase 1 contract for the pusher escape system. They also "completed work on the other aspect of its award, risk reduction work on a composite pressure vessel" for the vehicle.

Commercial suborbital flights


Passenger flights

Following the fifth and final test flight of the NS2 booster and test capsule in October 2016, Blue Origin indicated that they were on track for flying test astronauts by the end of 2017, and beginning commercial suborbital passenger flights in 2018. Blue Origin made no passenger flights in 2017, and in December 2017, stated they remained "about a year away from starting to fly people."

NASA suborbital research payloads

As of March 2011, Blue Origin had submitted the New Shepard reusable launch vehicle for use as an uncrewed rocket for NASA's suborbital reusable launch vehicle (sRLV) solicitation under NASA's Flight Opportunities Program. Blue Origin projects 100 km (330,000 ft) altitude in flights of approximately ten minutes duration, while carrying an 11.3 kg (25 lb) research payload. By March 2016, Blue noted that they are "due to start flying unaccompanied scientific payloads later [in 2016]."

Delta IV

From Wikipedia, the free encyclopedia
https://en.wikipedia.org/wiki/Delta_IV
 
Delta IV (Delta 9000)
Delta IV Medium Rocket DSCS.jpg
Delta IV Medium launch carrying DSCS III-B6
FunctionOrbital launch vehicle
ManufacturerUnited Launch Alliance
Country of originUnited States
Cost per launchUS$164+ million
Size
Height63–72 m (207–236 ft)
Diameter5 m (16 ft)
Mass249,500–733,400 kg (550,100–1,616,900 lb)
Stages2
Capacity
Payload to LEO11,470–28,790 kg (25,290–63,470 lb)
Payload to
GTO
4,440–14,220 kg (9,790–31,350 lb)
Associated rockets
FamilyDelta (rocket family)
Comparable
Launch history
StatusDelta IV Heavy is active; Delta IV Medium, M+(4,2), M+(5,2), and M+(5,4) retired.
Launch sitesSLC-37B, Cape Canaveral
SLC-6, Vandenberg AFB
Total launches
40
  • Medium: 3
  • M+ (4,2): 15
  • M+ (5,2): 3
  • M+ (5,4): 8
  • Heavy: 11
Successes
39
  • Medium: 3
  • M+ (4,2): 15
  • M+ (5,2): 3
  • M+ (5,4): 8
  • Heavy: 10
Partial failures1 (Heavy)
First flight
Last flight
  • Medium/M+: 22 August 2019 (USA-293/GPS III-2)
  • Heavy: 19 January 2019 (NROL-71)
Notable payloads
Boosters (Medium+) – GEM 60
No. boostersMedium+ (4,2), Medium+ (5,2): 2
Medium+ (5,4): 4
Gross mass33,638 kg (74,158 lb)
Thrust826.6 kN (185,800 lbf)
Specific impulse245 s (2.40 km/s) (sea level)
Burn time91 seconds
FuelHTPB / Aluminum
Boosters (Heavy) – Common Booster Core (CBC)
No. boosters2
Gross mass226,400 kg (499,100 lb)
Engines1 RS-68A
Thrust3,140 kN (705,000 lbf) (sea level)
Specific impulseSea level: 360 s (3.5 km/s) Vacuum: 412 s (4.04 km/s)
Burn time242 seconds[2]
FuelLH2 / LOX
First stage – CBC
Gross mass226,400 kg (499,100 lb)
Engines1 RS-68A
Thrust3,140 kN (705,000 lbf) (sea level)
Specific impulseSea level: 360 s (3.5 km/s) Vacuum: 412 s (4.04 km/s)
Burn time245 seconds (328 seconds in Heavy configuration)
FuelLH2 / LOX
Second stage – Delta Cryogenic Second Stage (DCSS)
Gross mass4-m: 24,170 kg (53,290 lb)
5-m: 30,700 kg (67,700 lb)
Engines1 RL10-B-2
Thrust110 kN (25,000 lbf)
Specific impulse462 s (4.53 km/s)
Burn time850-1,125 seconds
FuelLH2 / LOX

Delta IV is a group of five expendable launch systems in the Delta rocket family introduced in the early 2000s. Originally designed by Boeing's Defense, Space & Security division for the Evolved Expendable Launch Vehicle (EELV) program, the Delta IV became a United Launch Alliance (ULA) product in 2006. The Delta IV was and is primarily a launch vehicle for United States Air Force military payloads, but has also been used to launch a number of U.S. government non-military payloads and a single commercial satellite.

The Delta IV originally had two main versions which allowed the family to cover a range of payload sizes and masses: the retired Medium (which had four configurations) and Heavy. As of 2019, only the Heavy remains active, with payloads that would previously fly on Medium moving to either the existing Atlas V or the forthcoming Vulcan. Retirement of the Delta IV is anticipated in 2024.

Delta IV vehicles are built in the ULA facility in Decatur, Alabama. Final assembly is completed at the launch site by ULA: at the Horizontal Integration Facility for launches from SLC-37B pad at Cape Canaveral and in a similar facility for launches from SLC-6 pad at Vandenberg Air Force Base.

History

The latest evolutionary development of the Delta rocket family, Delta IV was introduced to meet the requirements of the United States Air Force's (USAF's) Evolved Expendable Launch Vehicle (EELV, now national security space launch/NSSL) program. While the Delta IV retains the name of the Delta family of rockets, major changes were incorporated. Perhaps the most significant change was the switch from kerosene to liquid hydrogen fuel, with new tankage and a new engine required.

During the Delta IV's development, a Small variant was considered. This would have featured the Delta II second stage, an optional Thiokol Star 48B third stage, and the Delta II payload fairing, all atop a single Common Booster Core (CBC). The Small variant was dropped by 1999.

In 2002, the Delta IV was first launched, with the RS-68 becoming the first large liquid-propellant rocket engine designed in the U.S. since the Space Shuttle main engine (SSME) in the 1970s. The primary goal for the RS-68 was to reduce cost versus the SSME. Some sacrifice in chamber pressure and specific impulse was made, hurting efficiency; however, development time, part count, total cost, and assembly labor were reduced to a fraction of the SSME, despite the RS-68's significantly larger size.

The L3 Technologies Redundant Inertial Flight Control Assembly (RIFCA) guidance system originally used on the Delta IV was common to that carried on the Delta II, although the software was different because of the differences between the Delta II and Delta IV. The RIFCA featured six ring laser gyroscopes and accelerometers each, to provide a higher degree of reliability.

Boeing initially intended to market Delta IV commercial launch services. However, the Delta IV entered the space launch market when global capacity was already much higher than demand. Furthermore, as an unproven design it had difficulty finding a market in commercial launches, and Delta IV launch costs are higher than comparable vehicles of the same era. In 2003, Boeing pulled the Delta IV from the commercial market, citing low demand and high costs. In 2005, Boeing stated that it sought to return the Delta IV to commercial service.

As of 2009, the USAF funded Delta IV EELV engineering, integration, and infrastructure work through contracts with Boeing Launch Services (BLS). On August 8, 2008, the USAF Space and Missile Systems Center increased the "cost plus award fee" contract with BLS for $1.656 billion to extend the period of performance through the end of FY09. In addition a $557.1 million option was added to cover FY10. However, the Delta IV series was at that time launched by the United Launch Alliance (ULA), a joint venture between Boeing and Lockheed Martin.

In February 2010, naturalized citizen Dongfan Chung, an engineer working with Boeing, was the first person convicted under the Economic Espionage Act of 1996. Chung passed on classified information on designs including the Delta IV rocket and was sentenced to 15 years.

In March 2015, ULA announced plans to phase out the Delta IV Medium by 2018. The Delta IV will be replaced by the Atlas V in the near term and Vulcan in the far term. The Delta IV Medium was actually retired on 22 August 2019. 

With the exception of the first launch, which carried the Eutelsat W5 commercial communications satellite, all Delta IV launches have been paid for by the US government. In 2015, ULA stated that a Delta IV Heavy is sold for nearly $400 million.

RS-68A booster engine upgrade

The possibility of a higher performance Delta IV was first proposed in a 2006 RAND Corporation study of national security launch requirements out to 2020. A single National Reconnaissance Office (NRO) payload required an increase in the lift capability of the Delta IV Heavy. Lift capacity was increased by developing the higher-performance RS-68A engine, which first flew on June 29, 2012. ULA phased out the baseline RS-68 engine with the launch of Delta flight 371 on March 25, 2015. All following launches have used the RS-68A, and the engine's higher thrust allowed the use of a single standardized CBC design for all Delta IV Medium and M+ versions. This upgrade reduced cost and increased flexibility, since any standardized CBC could be configured for zero, two, or four solid boosters. However, the new CBC led to a slight performance loss for most medium configurations. The Delta IV Heavy still requires non-standard CBCs for the core and boosters.

Payload capacities after RS-68A upgrade
 
Version Fairing CBCs SRBs Payload to LEO 407 km x 51.6°
Payload to GTO 1800 m/s residual
Launches to date
Medium 4 m 1 0 8,510 kg 4,440 kg 0
M+(4,2) 4 m 1 2 12,000 kg 6,390 kg 2
M+(5,2) 5 m 1 2 10,220 kg 5,490 kg 2
M+(5,4) 5 m 1 4 12,820 kg 7,300 kg 4
Heavy 5 m 3 0 25,980 kg 14,220 kg 4

Payload capacities with original RS-68
 
Version
Fairing
CBCs
SRBs
Payload to LEO
407 km x 51.6°
Payload to GTO
1800 m/s residual
Launches to date
Medium 4 m 1 0 8,800 kg 4,540 kg 3
M+(4,2) 4 m 1 2 11,920 kg 6,270 kg 13
M+(5,2) 5 m 1 2 10,580 kg 5,430 kg 1
M+(5,4) 5 m 1 4 13,450 kg 7,430 kg 4
Heavy 5 m 3 0 22,980 kg 13,400 kg 7

Proposed upgrades that were not implemented

Possible future upgrades for the Delta IV included adding extra strap-on solid motors, higher-thrust main engines, lighter materials, higher-thrust second stages, more (up to six) strap-on CBCs, and a cryogenic propellant cross feed from strap on boosters to the common core.

At one point NASA planned to use Delta IV or Atlas V to launch the proposed Orbital Space Plane, which eventually became the Crew Exploration Vehicle and then the Orion. Orion was intended to fly on the Ares I launch vehicle, then the Space Launch System after Ares I was cancelled.

In 2009 The Aerospace Corporation reported on NASA results of a study to determine the feasibility of modifying Delta IV to be human-rated for use in NASA human spaceflight missions. According to Aviation Week the study, "found that a Delta IV heavy [...] could meet NASA's requirements for getting humans to low Earth orbit."

A proposed upgrade to the Delta IV family was the addition of extra solid motors. The Medium+(4,4) would have used existing mount points to pair the four GEM-60s of the M+(5,4) with the upper stage and fairing of the (4,2). An M+(4,4) would have had a GTO payload of 7,500 kg (16,600 lb), a LEO payload of 14,800 kg (32,700 lb), and could have been available within 36 months of the first order. It was also considered to add extra GEM-60s to the M+(5,4), which would have required adding extra attachment points, structural changes to cope with the different flight loads, and launch pad and infrastructure changes. The Medium+(5,6) and (5,8) would have flown with six and eight SRBs respectively, for a maximum of up to 9,200 kg/20,200 lb to GTO with the M+(5,8). The Medium+(5,6) and (5,8) could have been available within 48 months of the first order.

Planned successor

The Vulcan rocket is planned to replace the Atlas V and Delta IV rockets. Vulcan is projected to enter service by 2021, using the Blue Origin BE-4 methane-fueled rocket engine. The Delta IV Heavy and Atlas V are expected to stay in service for a few years after Vulcan's inaugural launch, and the Heavy is expected to be discontinued by 2024.

Vehicle description

Delta IV evolution
 

Delta IV Medium

The Delta IV Medium was available in four configurations: Medium, Medium+ (4,2), Medium+ (5,2), and Medium+ (5,4). 

The Delta IV Medium (Delta 9040) was the most basic Delta IV. It featured a single CBC and a modified Delta III second stage, with 4-meter liquid hydrogen and liquid oxygen tanks and a 4-meter payload fairing. The Delta IV Medium was capable of launching 4,200 kg to geosynchronous transfer orbit (GTO). From Cape Canaveral, GTO is 1804 m/s away from GEO. The mass of fairing and payload attach fittings have been subtracted from the gross performance. It flew last time on 22 August 2019.

The Delta IV Medium+ (4,2) (Delta 9240) had the same CBC and DCSS as the Medium, but with the addition of two Orbital ATK-built 1.5-m (60-in) diameter solid rocket booster Graphite-Epoxy Motors (GEM-60s) strap-on boosters to increase payload capacity to 6,150 kg to GTO.

The Delta IV Medium+ (5,2) (Delta 9250) was similar to the Medium+ (4,2), but had a 5-m–diameter DCSS and payload fairing for larger payloads. Because of the extra weight of the larger payload fairing and second stage, the Medium+ (5,2) could launch 5,072 kg to GTO.

The Delta IV Medium+ (5,4) (Delta 9450) was similar to the Medium+ (5,2), but used four GEM-60s instead of two, enabling it to lift 6,882 kg to GTO.

To encapsulate the satellite payload, a variety of different payload fairings were available. A stretched Delta III 4 meter diameter composite payload fairing was used on 4 meter Medium versions, while an enlarged, 5 meter diameter composite fairing was used on 5 meter Medium versions.

Delta IV Heavy

Delta IV Heavy launching

The Delta IV Heavy (Delta 9250H) combines a 5-meter (16 ft) diameter DCSS and payload fairing with two additional CBCs. These are strap-on boosters which are separated earlier in the flight than the center CBC. As of 2007, a longer 5 meter diameter composite fairing was standard on the Delta IV Heavy, with an aluminum isogrid fairing also available. The aluminum trisector (three-part) fairing was built by Boeing and derived from a Titan IV fairing. The trisector fairing was first used on the DSP-23 flight. The Delta IV with the extended fairing is over 62 m (205 ft) tall. 

Common Booster Core

Each Delta IV consists of at least one Common Booster Core (CBC). Each CBC is powered by one Aerojet Rocketdyne RS-68 engine, which burns liquid hydrogen and liquid oxygen.

On flights of the Medium, the RS-68 ran at 102% rated thrust for the first few minutes of flight, and then throttled down to 58% rated thrust before main engine cutoff. On the Heavy, the main CBC's engine throttles down to 58% rated thrust around 50 seconds after liftoff, while the strap-on CBCs remain at 102%. This conserves propellant and allows the main CBC to burn after booster separation. After the strap-on CBCs separate, the main CBC's engine throttles back up to 102% before throttling back down to 58% prior to main engine cutoff.

The RS-68 engine is mounted to the lower thrust structure of the CBC by a four-legged (quadrapod) thrust frame and enclosed in a protective composite conical thermal shield. Above the thrust structure is an aluminum isogrid (a grid pattern machined out of the inside of the tank to reduce weight) liquid hydrogen tank, followed by a composite cylinder called the centerbody, an aluminum isogrid liquid oxygen tank, and a forward skirt. Along the back of the CBC is a cable tunnel to hold electrical and signal lines, and a feedline to carry the liquid oxygen to the RS-68 from the tank. The CBC is of a constant, 5-meter (16.4 ft) diameter.

Delta Cryogenic Second Stage

Delta IV 4-Meter Second Stage

The upper stage of the Delta IV is the Delta Cryogenic Second Stage (DCSS). The DCSS is based on the Delta III upper stage but has increased propellant capacity. Two versions have been produced: a 4-meter (13.1 ft) diameter DCSS that was retired with the Delta IV Medium and a 5-meter diameter DCSS that remains in service with the Delta IV Heavy. The 4 m diameter version lengthened both Delta III propellant tanks, while the 5-meter version has an extended diameter liquid hydrogen tank and a further lengthened liquid oxygen tank. Regardless of the diameter, each DCSS is powered by one RL10B2 engine, with an extendable carbon-carbon nozzle to improve specific impulse. Two different interstages are used to mate the first stage and DCSS. A tapering interstage that narrowed down from 5 m to 4 m diameter was used to mate the 4 m DCSS to the CBC, while a cylindrical interstage is used to mate the 5 m DCSS. Both interstages were built from composites and enclosed the liquid oxygen tank, with the larger liquid hydrogen tank making up part of the vehicle's outer mold line.

Launch sites

First Delta IV Heavy with three CBCs prior to launch
 
Delta IV launches occur from either of two rocket launch complexes. Launches on the East coast of the United States use Space Launch Complex 37 (SLC-37) at the Cape Canaveral Air Force Station. On the West coast, polar-orbit and high-inclination launches use Vandenberg Air Force Base's Space Launch Complex 6 (SLC-6).

Launch facilities at both sites are similar. A Horizontal Integration Facility (HIF) is situated some distance from the pad. Delta IV CBCs and second stages to be mated and tested in the HIF before they are moved to the pad. The partial horizontal rocket assembly of the Delta IV is somewhat similar to the Soyuz launch vehicle, which is completely assembled horizontally. The Space Shuttles, the past Saturn launch vehicles, and the upcoming Space Launch System are assembled and rolled out to the launch pad entirely vertically.

Movement of the Delta IVs among the various facilities at the pad is facilitated by rubber-tired Elevating Platform Transporters (EPTs) and various transport jigs. Diesel engine EPTs are used for moving the vehicles from the HIF to the pad, while electric EPTs are used in the HIF, where precision of movement is important.

The basic launchpad structure includes a flame trench to direct the engine plume away from the rocket, lightning protection, and propellant storage. In the case of Delta IV, the vehicle is completed on the launch pad inside a building. This Mobile Service Tower (MST) provides service access to the rocket and protection from the weather and is rolled away from the rocket on launch day. A crane at the top of the MST lifts the encapsulated payload to the vehicle and also attached the GEM-60 solid motors for Delta IV Medium launches. The MST is rolled away from the rocket several hours before launch. At Vandenberg, the launch pad also has a Mobile Assembly Shelter (MAS), which completely encloses the vehicle; at CCAFS, the vehicle is partly exposed near its bottom.

Beside the vehicle is a Fixed Umbilical Tower (FUT), which has two (VAFB) or three (CCAFS) swing arms. These arms carry telemetry signals, electrical power, hydraulic fluid, environmental control air flow, and other support functions to the vehicle through umbilical lines. The swing arms retract at T-0 seconds once the vehicle is committed to launch.

Under the vehicle is a Launch Table, with six Tail Service Masts (TSMs), two for each CBC. The Launch Table supports the vehicle on the pad, and the TSMs provide further support and fueling functions for the CBCs. The vehicle is mounted to the Launch Table by a Launch Mate Unit (LMU), which is attached to the vehicle by bolts that sever at launch. Behind the Launch Table is a Fixed Pad Erector (FPE), which uses two long-stroke hydraulic pistons to raise the vehicle to the vertical position after being rolled to the pad from the Horizontal Integration Facility (HIF). Beneath the Launch Table is a flame duct, which deflects the rocket's exhaust away from the rocket or facilities.

Vehicle processing

Delta IV CBCs and DCSSs are assembled at ULA's factory in Decatur, Alabama. They are then loaded onto the M/V Delta Mariner, a roll-on/roll-off cargo vessel, and shipped to either launch pad. There, they are offloaded and rolled into a Horizontal Integration Facility (HIF). For Delta IV Medium launches, the CBC and DCSS were mated in the HIF. For Delta IV Heavy launches, the port and starboard strap-on CBCs are also mated in the HIF.

Various tests are performed, and then the vehicle is rolled horizontally to the pad, where the Fixed Pad Erector (FPE) is used to raise the vehicle to the vertical position. At this time, the GEM-60 solid motors, if any are required, are rolled to the pad and attached to the vehicle. After further testing, the payload (which has already been enclosed in its fairing) is transported to the pad, hoisted into the MST by a crane, and attached to the vehicle. Finally, on launch day, the MST is rolled away from the vehicle, and the vehicle is ready for launch.

Notable launches

GOES-N launch on a Medium+ (4,2)
 
A unique aerial view of NROL-22 launch from SLC-6
 
The first payload launched with a Delta IV was the Eutelsat W5 communications satellite. A Medium+ (4,2) from Cape Canaveral carried the communications satellite into geostationary transfer orbit (GTO) on 20 November 2002.

Heavy Demo was the first launch of the Delta IV Heavy in December 2004 after significant delays due to bad weather. Due to cavitation in the propellant lines, sensors on all three CBCs registered depletion of propellant. The strap-on CBCs and then core CBC engines shut down prematurely, even though sufficient propellant remained to continue the burn as scheduled. The second stage attempted to compensate for the shutdown and burned until it ran out of propellant. This flight was a test launch carrying a payload of:
  • DemoSat – 6020 kg; an aluminum cylinder filled with 60 brass rods – planned to be carried to GEO; however due to the sensor faults, the satellite did not reach this orbit.
  • NanoSat-2, carried to low Earth orbit (LEO) – a set of two very small satellites of 24 and 21 kg, nicknamed Sparky and Ralphie – planned to orbit for one day. Given the under-burn, the two most likely did not reach a stable orbit.
NROL-22 was the first Delta IV launched from SLC-6 at Vandenberg Air Force Base (VAFB). It was launched aboard a Medium+ (4,2) in June 2006 carrying a classified satellite for the U.S. National Reconnaissance Office (NRO).

DSP-23 was the first launch of a valuable payload aboard a Delta IV Heavy. This was also the first Delta IV launch contracted by the United Launch Alliance, a joint venture between Boeing and Lockheed Martin. The main payload was the 23rd and final Defense Support Program missile-warning satellite, DSP-23. Launch from Cape Canaveral occurred on November 10, 2007.

NROL-26 was the first Delta IV Heavy EELV launch for the NRO. USA 202, a classified reconnaissance satellite, lifted off 18 January 2009.

NROL-32 was a Delta IV Heavy launch, carrying a satellite for NRO. The payload is speculated to be the largest satellite sent into space. After a delay from 19 October 2010, the rocket lifted off on 21 November 2010.

NROL-49 lifted off from Vandenberg AFB on January 20, 2011. It was the first Delta IV Heavy mission to be launched out of Vandenberg. This mission was for the NRO and its details are classified.

On October 4, 2012, a Delta IV M+ (4,2) experienced an anomaly in the upper stage's RL10-B-2 engine which resulted in lower than expected thrust. While the vehicle had sufficient fuel margins to successfully place the payload, a GPS Block IIF satellite, into its targeted orbit, investigation into the glitch delayed subsequent Delta IV launches and the next Atlas V launch (AV-034) due to commonality between the engines used on both vehicles' upper stages. By December 2012, ULA had determined the cause of the anomaly to be a fuel leak, and Delta IV launches resumed in May 2013. After two more successful launches, further investigation led to the delay of Delta flight 365 with the GPS IIF-5 satellite. Originally scheduled to launch in October 2013, the vehicle lifted off on February 21, 2014.

A Delta IV Heavy launched the Orion spacecraft on an uncrewed test flight, EFT-1, on December 5, 2014. The launch was originally planned for December 4, but high winds and valve issues caused the launch to be rescheduled for December 5.

The second GPS Block III satellite was launched with the final Delta IV Medium in the +(4,2) configuration on 22 August 2019.

Representation of a Lie group

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