After too much teasing, the Air Force finally revealed the B-21 Raider. The event occurred at Northrop Grumman’s facility in Palmdale, California, where six B-21s are currently in various stages of production.
B-2.1
As expected, the B-21 matches the artist’s renderings and looks like a B-2 with a makeover, so much so that you could call it the B-2.1. This makes sense since Northrop built both bombers and is leveraging its B-2 know-how.
The tail wasn’t revealed, but you can tell it's a simple W-shape by looking at the shadow in this official Air Force photo.
This design is optimized for high-altitude flight and matches the artist's renderings...and the original B-2 design.
That’s right, the original B-2 looked very similar to the B-21…until the Air Force added a low-altitude requirement in the mid-1980s. This forced Northrop to redesign the B-2’s backend into the saw-tooth shape you see today.
It’s Small(er)
Internet sleuths and defense media have speculated that the B-21 has a smaller wingspan than the B-2.
It’s slightly smaller, but size comparisons aren’t linear since the B-2 and B-21 are slightly different designs. A more accurate proxy is weight, from which you can have range and payload debates.
We think the B-21 weighs 75% less than the B-2 for two reasons that may not be obvious:
1. Landing Gear: The B-21 only has two wheels on each main landing gear (MLG), whereas the B-2 has four. This is a critical design feature since the main landing gear is what determines the max weight. That’s why every other bomber and mobility aircraft has multiple wheels—with one exception.
- The C-130 uses a two-wheel bicycle design main landing gear, which supports a max takeoff weight of ~170,000 lbs. This is far less than the B-2’s 376,000 lb. limit, but the C-130 is a 70-year-old design.
- On a traditional side-by-side landing gear axle, we imagine these wheels could take much more weight, perhaps upwards of 280,000 lbs.
- The B-21 gear and wheels look different than the stuff on the current C-130, C-17, B-1B, B-2, and B-52
- Our hunch is they might be the new B-52 wheels and brakes that Collins Aerospace is on contract for…but they do look very similar to an airliner wheel too
Engines: We believe that the B-21 will be powered by two F-35 engines (the F135). Our logic:
- The B-21 will utilize an existing engine design, and Pratt & Whitney (P&W) is the confirmed engine producer.
- The B-21 serpentine intakes and mold line all but confirm a single engine on each side of the cockpit.
- Like all flying wing designs with embedded engines, the B-21 will not have afterburners because it won't need them; flying wing designs don't go supersonic.
- P&W has two active engines that could fit the bill. The F100-229 is used on the F-15E/F-16 and has 18,000 lbs. of mil thrust. The F-135 is used on the F-35 and has 28,000 lbs. of mil thrust.
- The B-2 uses four GE F118 engines with 19,000 lbs. of thrust (76k total). Using two F-100-229 engines (36K lbs.) is too little, and four -229 engines (72K lbs.) is too much, too expensive, and wouldn’t fit the B-21 mold line
- Two F-135 engines—the newest military engine in use—would put the thrust right in the middle (56K lbs.)
- This means the B-21 will have 25% less power than the B-2. Assuming the B-21 keeps the B-2’s 0.2 thrust-to-weight ratio, the B-21’s max weight would be 282,000 lbs. That checks with our landing gear assessment.
Secrets to Success
The program is relatively on time and budget, which not only makes it an outlier in defense acquisitions, but also heavily influenced what capabilities the B-21 would have, what it would look like, and how it would be built.
Contract(s): The B-21 was developed with a dual-contract structure. Development is being done under a cost-plus-incentive contract that puts the risk on the Air Force for time/cost overruns. Once developed, production (buying the bombers) is via a firm-fixed-price contract, meaning that all the risk shifts to Northrop.
- Fun Fact: Fixed price contracts can be a good thing or a terrible thing. Boeing’s VC-25 (aka Air Force One), KC-46, MQ-25, and T-7 programs have all made news recently for their fixed-price contracts—and not in a good way.
Capability Capped: In 2010, the Air Force capped the price at $550m per bomber (which is $750m in today’s dollars). Time and cost would be controlled not by developing new tech—but by limiting the scope to what was essential for the airframe development and integration. This did three things: 1) prevented requirements creep, 2) forced the harvesting of proven tech from other programs, and 3) canceled or off-boarded some higher-end capabilities.
- Fun Fact: The latter is why the LRS-B program, from which the B-21 originated, had a hyphen in the name. The simplified bomber (-B) is intended to be part of a Long Range Strike (LRS) family of systems. Over time, the media shortened it to LRSB, and it stuck.
Stealing Parts: Details are scarce, but the B-21’s sensors, datalinks, cockpit displays, avionics, and a fair amount of sub-systems are likely to come from the F-22 and F-35 parts bins, as well as from capability upgrades that are already underway across other platforms.
- Fun Fact: This is the same approach the F-117 program used and was the reason it was the last time a military aircraft was developed on time (6 years!). The F-117 used an F-16 computer, F-15 brakes, F-18 engines and HUD, a C-130 environmental control system, F-111 flight control actuators, and a B-52 inertial navigation system.
What Now
Want to know more? Sure you do!
There was no way we could squeeze all the goodness into print this week…
…so we’re joining Ward “Mooch” Carroll on his YouTube channel for a live-stream discussion on the B-21 Raider!
Vul time is 2000 Zulu (that’s 3:00 pm US Eastern Time in civilian speak).
See you there!
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