Quelle: Northrop Grumman
Second B-21 Under Construction as Bomber Moves Toward First Flight
Artist rendering of a B-21 Raider concept in a hangar at Dyess Air Force Base, Texas, one of the future bases to host the new airframe. Photo: Courtesy of Northrop Grumman via USAF.
Production of a second B-21 stealth bomber is underway at Northrop Grumman’s facility in Palmdale, Calif., while the first Raider is expected to roll out in early 2022 and fly in the middle of that year, according to Randall Walden, director of the Air Force Rapid Capabilities Office.
The Air Force predicted it could fly the secretive B-21 for the first time in December 2021. But in an exclusive interview with Air Force Magazine, Walden said that forecast was always a best-case scenario, and that first flight in mid-2022 is now a “good bet.”
The first Raider hasn’t yet reached final assembly, he said, but is “really starting to look like a bomber.” A second plane, now moving down the production line, will allow the Air Force to vet the airframe, Walden said.
“The second one is really more about structures, and the overall structural capability,” he explained. “We’ll go in and bend it, we’ll test it to its limits, make sure that the design and the manufacturing and the production line make sense.”
Lt. Gen. James C. Dawkins, Jr., deputy chief of staff for strategic deterrence and nuclear integration, said Jan. 14 that the B-21 will be available for service around 2026 or 2027. According to the Congressional Budget Office in 2018, the Air Force estimated the cost of developing and buying the first 100 aircraft at $80 billion in 2016 dollars.
The bomber leg of the nuclear triad is comprised of “B-52s and B-2s, and in another six or seven years, the B-21,” Dawkins said during a Heritage Foundation event on the nuclear-tipped Long-Range Standoff Weapon.
Lessons learned from producing the first airplane are being applied to the second, Walden said. That work is progressing “much faster” as workers figure out how to build the airplane in real life, rather than operating off of a blueprint’s assumptions. The team is creating more space for test aircraft as the two bombers come together, he added.
“It’s looking pretty good,” Walden said. “We’re very pleased with the … very high percentages of efficiency” in building the second aircraft, “as compared to No. 1.”
First flight will only happen after elaborate coordination with Northrop Grumman, major suppliers, and the test community to ensure “that we are ready to go,” Walden said.
“Just like any aircraft program, there’s going to be surprises” during engine runs and other prep work that could affect first flight, he said. “We will correct those as it makes sense.”
Program officials are trying to mitigate the coronavirus pandemic’s effects on the aerospace industry before they can drastically affect the B-21’s progress.
“Suppliers across the country are actively delivering parts to Palmdale and we’re doing what we can to help in that regard,” Walden said. The program is closely working with the supply base to ensure slower parts delivery don’t delay the airplanes at the same rate.
“It seems to be working quite well,” he said.
Spirit Aviation of Wichita, Kan., which supplies aerostructures on the B-21, shifted workers from Boeing’s 737 branch to the B-21 at the program’s request. That bolstered the B-21 effort by repurposing Boeing 737 MAX workers who otherwise would have been laid off, Walden said.
Orders for the MAX have dried up in the aftermath of that airplane’s two deadly crashes and the steep dropoff in air travel during the pandemic.
“The pandemic has slowed us in certain areas, but I think we have compensated,” Walden said. “I don’t think we’ve got significant delays to … first flight.”
Delays on the production line “will be mitigated,” he added, and any changes to the 2022 timeline will be communicated to Pentagon and congressional leadership. He believes the Air Force may bring more details about the bomber to light as its debut flight nears.
Walden also said the program is reducing risk by using a business-class jet as an avionics testbed, working out hardware and software kinks before transferring them to the B-21. Randall said it was analogous to Lockheed Martin’s Cooperative Avionics Testbed aircraft—nicknamed CATbird.
“We’re getting a lot of good feedback” from this effort, Walden said. The business jet is flying “real B-21 software” and helping illustrate how sensors and code will be added into the bomber test fleet.
“In the last few months, we did another successful end-to-end demonstration to further mature that hardware and software, and it’s working quite well,” Walden said. “We’re working not only in the flight test activities, but also working with the government test infrastructure to make sure that what we’re doing, from a system integration point of view, makes sense.”
“We’re preparing ourselves not just for first flight, but ultimately, the subsystem testing that will be required during those flight test phases,” he added.
Hardware and software will be vetted on the ground and in the air, and the bomber development team has “a lot of confidence” about powering up the first aircraft for its maiden voyage thanks to the risk-reduction efforts, Walden said.
As ranking member on the House Armed Services seapower and projection forces subcommittee, Rep. Rob Wittman (R-Va.) is one lawmaker tasked with oversight of the multibillion-dollar program that is among the Pentagon’s top acquisition priorities to counter other advanced militaries. In 2018, Wittman said the B-21 was experiencing thrust issues related to the bomber’s inlet and serpentine ducting.
Those issues were fixed, Walden said.
“Overall, what Congressman Wittman did bring up was an example of one of those ‘surprises,’” Walden said. “We made that work.”
He declined to discuss the technical details of the problem, but said the fix “required some … basic changes to the design, of which we have a good understanding today through ground testing and engine testing.”
“It looks like we have solved it and we are moving forward with that final design,” Walden said.
Raytheon Technologies’s acquisition of engine maker Pratt & Whitney hasn’t caused hiccups for the B-21, and the change has been transparent, he noted.
Walden also reported that the beddown program is going well, saying a recent industry day at Ellsworth AFB, S.D., to discuss military construction and other support projects was a success.
The Air Force plans to spend about $300 million on military construction projects for the B-21 in fiscal 2022, Walden said, and $1 billion over five years. The service requested $2.8 billion for the plane’s research and development in fiscal 2021 alone, though the price tag is still evolving.
Quelle: AIR FORCE MAGAZINE
New B-21 Stealth Bomber Image Shows Stealth Windows
Shown is a B-21 Raider artist rendering that highlights the future stealth bomber at Edwards Air Force Base, Calif. Designed to perform long-range conventional and nuclear missions and to operate in tomorrow’s high-end threat environment, the B-21 will be a visible and flexible component of the nuclear triad. Air Force graphic.
The Air Force’s newest rendering of the secret B-21 bomber shows an exotic layout of cockpit windows. The image, the third released so far, offers a new oblique view of the aircraft from below its port side, suggesting a deeper keel and wider weapons bay than that of the B-2 bomber it will succeed. But the air intakes, which have been redesigned, are obscured.
The new B-21 Raider image was published July 6 along with a new fact sheet. The Air Force identified it as an “artist’s interpretation.” It shows the aircraft taking off from Edwards Air Force Base, Calif., where it will be flight tested beginning early next year. The prior official illustrations were released in January 2021 and in February 2016.
The new picture shows a triangular, curved main forward cockpit window and a wide, arcing side window with no apparent interior framing. That departs from earlier views which showed B-2-style windows. Just aft of the side window is the Global Strike Command badge and stenciling for ground rescue instructions.
The nose of the aircraft confirms a more pronounced “Beak” or “Hawk’s bill” than on the B-2 Spirit, which the B-21 generally resembles. The underside of the aircraft seems to be deeper than the B-2, although details are obscured. When compared with the artist’s rendering released in January, the B-21 seems to have a greatly pronounced chine, or flattened leading edge, which then tapers into the blended-wing fuselage. This chine also marks a departure from the B-2, which has a more classic wing-like chord shape in cross section.
Northrop’s stealthy YF-23, which lost out to the F-22 in USAF’s Advanced Tactical Fighter competition some 30 years ago, also featured extended chines on the leading edges. The company’s X-47 autonomous carrier aircraft demonstrator featured an extended Hawk’s bill like that on the B-21.
The image obscures details of the B-21’s air intake, which underwent a “major redesign,” according to Program Executive Officer Randall Walden. He told Air Force Magazine early this year such a change is typical for a complex new aircraft program. New aircraft often have “installed engine inlet/exhaust integration issues that have to be resolved,” he said. Previous images have shown the intakes as shallow and straight-edged, unlike the B-2’s scalloped, rounded, and deep intakes.
Also absent from the new image is any detail of the exhaust, although it continues to show a tapered, pointed single tail in silhouette.
The image also suggests a two-tone paint scheme on the aircraft, with lighter gray above and darker gray below. There’s a sharp color break below the window, and the GSC badge is in dark gray, whereas such markings are in light gray on the B-2, to better contrast with that aircraft’s FS 36118 overall “Gunship Gray” paint scheme.
The January 2016 image also revealed that the B-21 rests on two two-wheel main landing gear, while the larger B-2 has four-wheel bogeys on each side. The new image suggests a thickening of the outer wing as well.
The new fact sheet released with the image mentions major program milestones and emphasizes the jet’s open-mission systems concept, which will make upgrades easier and quicker to incorporate. It does not provide any details on performance or dimensions but notes that the first B-21 operating base will be at Ellsworth Air Force Base, S.D.
The fact sheet also mentions that the B-21 is part of the “larger family of systems” for conducting conventional long-range strike. This family includes “intelligence, surveillance and reconnaissance, electronic attack, communication and other capabilities,” the Air Force said. The fact sheet confirmed that the B-21 will be nuclear capable and is “designed to accommodate manned or unmanned operations … It will be able to employ a broad mix of stand-off and direct-attack munitions.”
The B-21’s name “Raider” honors the Doolittle Raiders who conducted the first bombing of Japan of World War II in retaliation for that country’s attack on Pearl Harbor, Hawaii. The April 1942 strike was carried out by B-25 Mitchell bombers flown off the aircraft carrier USS Hornet. The designation “B-21” refers to the first Air Force bomber of the 21st century.
The average procurement unit cost of the new bomber is $550 million in base year 2010 dollars; inflated to 2019, the cost is $639 million each, the fact sheet said.
First B-21 Moves to New Hangar for Loads Calibration
The first B-21 expected to fly is largely assembled and has moved to a calibration facility, in one of the last steps before powering systems and making final checks ahead of first flight, Rapid Capabilities Office Director Randall Walden reported.
In a sidebar at the AFA Warfare Symposium in Orlando, Fla., Walden noted that “we’ve taken the first one out” of the production facility.
“It’s got landing gear. … It’s got wheels on it … It’s got the wings on it. It really looks like a bomber,” Walden said. Six B-21s are now under construction at Northrop Grumman’s Palmdale facility, he said.
The loads calibration test is a “normal thing you do” and ensures the structure “is designed and built to what we actually meant it to do.” Once that’s done, “that gives us great insight into, ‘Did the actual design meet our needs, and did the manufacturing of that meet our needs?’”
The calibration test aircraft has not yet been assigned a tail number or name, he said, but it’s expected to be the first to fly. Walden said supply chain issues have not significantly affected the production program, but he declined to predict when the rollout and first flight would occur.
Though Walden said it’s “not my final call,” he thinks there will be a formal rollout “with senior leaders and press” because “it will be an historical event.”
Then, there will have to be some “even driven, data driven” events, such as putting power to the aircraft, starting the engines, testing the hydraulics, “everything you normally do in a ground test to make sure it’s working properly.” There also will be slow- and high-speed taxi tests, he added.
“Once all that data informs where we stand from a design [standpoint], is when we’ll schedule that first flight,” Walden said. The first flight will likely be a hop to nearby Edwards Air Force Base, Calif.
US Air Force will unveil its advanced new B-21 Raider stealth bomber on Dec. 2.