Rep. Rob Wittman, R-Va., said he was largely pleased with the work prime contractor Northrop Grumman did for the bomber program, praising in particular how the company did to integrate its subcontractors together to discover answers to early design problems. But he acknowledged there have been a couple of challenges that have sprouted.
“This is definitely an extraordinary, complex aircraft,” Wittman, that has oversight from the B-21, told reporters after a speech with the McAleese/Credit Suisse defense conference kept in Washington on Tuesday. “The dilemma is not really that you’ve these uncertainties. The problem is the way you address them.”
Wittman’s surveys are notable in the intense secrecy surrounding the B-21. The service plans to buy a minimum of 100 Raiders at a price around $550 million, really dollars, per copy. The engineering and manufacturing development phase has accomplished within separate, cost-plus contract that’s estimated to amount to about $21.4 billion.
Wittman highlighted many times the challenge of pushing air from the B-21’s engines. “This is definitely an, different design as far as airflow, and there has been some design challenges there,” he explained.
“Pratt and Whitney says a very important factor; in the event the exhaust, the ducting contractor says one more thing and says, ‘There’s only much air we can move through there,’ and Pratt & Whitney says, ‘No, we’d like some air to go from the front with the engine,’ then this question is: How do you do this?” Wittman added.
“Do you split certain requirements involving the two? Does Pratt & Whitney say: ‘Well, we can change some in the cowling the cover around the engine around the surface face there to be able to make it happen,’ he wondered, noting this as something that could impact the B-21’s low-observable characteristics.
“It’s not only the engine, but it’s the ducting for the engine, too. I think all those things are elements that you will normally expect within an aircraft that’s new, that can an idea from B-2, refines and uses it for this platform.”
Richard Aboulafia, an analyst while using Teal Group, noted widespread speculation the B-21 might be a twin-engine, instead of a quad-engine, plane. If that’s the situation, early tests may have shown airflow conditions could require the Air Force and Northrop to produce tough decisions on trade-offs because “turbines are hot and like large apertures, a pair of things that stealth hates.”
The B-2 uses four F118 engines, which produce about 17,000 pounds of thrust. Pratt & Whitney’s F135 engine, used in the F-35 Joint Strike Fighter and generally assumed being the basis for your engines employed in the B-21, can produce approximately 43,000 pounds of thrust, which often requires greater air intake. Hence, the cowling for the B-21 engines may need trade-offs involving the air coming in and the stealth characteristics.
For Aboulafia, that is “one from the most complicated parts of designing a stealth plane because there are many variables, but two of the very biggest are stealth and range.”
“The turbine thing speaks to a possible requirement of compromise. It’s not a deal-killer, but may that impact range? Sure. Range or stealth: Which would you like to compromise on? Or find some permutation therein,” he was quoted saying. “That’s the actual black art of aircraft design, the trade-offs.”
More broadly, Northrop has been challenged to engage “enough engineers” to produce sure the style stays on course, Wittman said, adding that the company is trying to receive an “Iron Bird” mock-up with the B-21 installed and operating, something would be the physical test bed for a few from the design and production elements.
The congressman also indicated there has been some “snags” with designing the wing for the B-21. It is believed Spirit AeroSystems is performing some of the project for the wing in their Wichita, Kansas, facility.
A spokesman for Northrop referred questions to the Air Force, while a spokesman for Pratt & Whitney declined to comment aside from to say the company was “proud” of their work around the program.
“The Air Force remains confident in the B-21’s progress along with delivering this new capability as planned inside mid-2020s,” Air Force spokeswoman Ann Stefanek said. “While we simply cannot talk with program specifics, the Air Force Rapid Capabilities Office is actively working using the contractor to ensure this software’s success.”
Other subcontractors for your Raider include BAE Systems, doing exercises of Nashua, New Hampshire; GKN Aerospace in St. Louis, Missouri; Janicki Industries in Sedro-Woolley, Washington; Orbital ATK in Clearfield, Utah, and Dayton, Ohio; and Rockwell Collins in Cedar Rapids, Iowa.
Though perhaps minor issues, they may be notable because part of Northrop’s plan to receive the plane from contract to initial operational capability in about 10 years involves an admittedly fast-moving schedule, one the Air Force has raised concerns about. And a part of that strategy for obtaining the bomber on time involved a significant amount of subsystem work.
If those advanced components are experiencing integration issues, even minor ones, it might force lag into a previously tight program-production window, at the same time in the event the Air Force is wanting to obtain the Raider fielded in order that it can start retiring the B-1 and B-2 bomber fleets.
“Integration is an issue,” Aboulafia said. “You can conserve time and effort with doing subsystems beforehand, but integration is always going to complicate things here where there. It doesn’t turn it into a total waste of time to perform these designs upfront, but integrating, that’s another issue.”
Overall, Wittman praised Northrop for sticking to an “aggressive” schedule and said the corporation has been very smart about identifying potential issues early and after that fitting in with smooth them out before true production begins.
“I have been impressed with the viewpoint that Northrop has using this, making use of their willingness to cope with things in a really timely way to become besides this,” he was quoted saying with the end of his remarks. “It is refreshing to see they may be tremendously seriously interested in thus, making this happen and that they are holding everyone around the B-21 team for this high standard.”