Due to how the rocket equation works (you have to accelerate all your fuel as well as payload), the amount of fuel required to reach a given velocity grows exponentially. So, an ideal platform to carry a hypersonic weapon would be one that flies fast in the first place and/or can carry a lot of mass. Imo something like the B-52 or B-1 would be more suited for it. That said, I'm not saying the B-21 won't have them, it's just that the B-21 doesn't really have any unique advantages in their use, other than that the B-21 has a long service life ahead of it.
The initial speed advantage of the B-1B is not that much though… B-21 gives out ~240m/s at M0.8 at high altitude, B-1B gives out ~370m/s. Assuming a solid fuel specific impulse of 265s, and an engine shut-off velocity of Mach 5 or 1500m/s at altitude. The missile sized for reaching Mach 5 from the B-21 would have to have 38% of its mass as fuel, while the missile sized for the same max velocity launching from a B-1B would only need to have 35% of its mass as fuel, which is not a large difference…
The small difference for the boost phase does matter a lot more for the sustainment time. I'm estimating ~16s for airbreathing missile or about 15 nm range, the whole range of former short range A2A missiles.
The front section does appear to be slightly longer than the rear section. Maybe 55/45 split. This combined with the slant of the panel makes up the 2 feet.
2,000lb JDAM is just under 13 feet long. So two of these bombs would fit perfectly in tandem on a rotary launder.
https://www.af.mil/About-Us/Fact-Sh...4572/joint-direct-attack-munition-gbu-313238/
Well worth clicking that link, impressive they produce the tail kit for $22k. Admittedly they make in (some) volume but still not a complete "rip-off". Here's the table someone (possibly Scott) shared previously.
Really? The B-2 has neither chaff nor flares? While relying on the reduction of it's radar signature and thermal signature is all nice and dandy paired with proper mission planning, isn't that a bit...risky?
I doubt they will put three mk82 bombs in tandem on the rotary launcher. This would require too many attachment points. It makes sense to have 8 mounts on the rear and 8 mounts on the front of the rotary launcher.
It has not
Huh, I never knew the B-1's top speed was Mach 1.2 (according to wikipedia), based on that, it's not that much of an upgrade. Beside that I don't think you need to get a hypothethical hypersonic missile up to Mach 5 - I think it has its own built in booster, so Mach ~3 might suffice. Anyway, most of it is conjecture, but I did find this pic of a Kinzhal (lets not argue about it being really hypersonic, I think we can agree it flies at M5+) mounted on both a MIG-31 and a Tu-22M:
Wait… Can you provide an image with AGM-183 having a booster fitted…? I have never seen that before…
No chaff , no flares. Imagine even a single piece of chaff getting hung up in a door after deployment flapping around, there goes your RCS.
By default 500 lb are not mounted to rotary launchers first. They are mounted to WWII esque arrangement & rack structures. This is true for B52, B2. The B1 got some weird half rotary for this but with same arrangement. A decade ago they upgraded its rotary to also accomodate 500 lb for a maximum of 32. I expect the B21 to return to the WWII like tradition as well as a better mor universal rotary system.
Hypersonic is defined as 5+ Mach so no fying at lower speeds. For ramjet to work they need to boost to their operational speed and that costs a lot of fuel for the missile which reduces fuel availabe for sustaining phase. So launching speed is limited to higher speeds.
Sorry, just did a bit of searching on Google, and some posts like this were implying this was a Kinzhal and looked similar enough:
Thanks for pointing it out, but even your reference shows that the finaly velocity differs when the launch platform has a different speed, moreover the difference in the final speed is more or less the same as the difference between the launch speeds, with the MIG 31 doing a bit better because of higher launch altitude, probably because the missile doesn't have to climb as much and enjoys less drag, but the final difference is like 3% (1.3% of which is explained by the difference in speed of sound).
I believe the latter “section” in the image you mentioned is just another AGM-183 missile…
Forgive me, I meant that the missile's last stage needs a minimum of Mach 3 to work - for traditional rockets, this is meaningless, since rockets mostly only care about delta-V. However I think most people agree, that the 'true' hypersonic weapons are scramjets, and those have a minimum speed to work, but they also come with their own boosters (afaik the Zircon has its intake duct filled with solid propellant, to accelerate the missile from launch to speeds where its scramjet works)
Maybe, you are right, however it looks like 1 piece to me.
This is probably a better photo confirming two missiles:
No, I highly doubt we will see a WWII style bomb rack developed for carpet bombing using Mk82.
Search for Smart Bomb Rack Assembly (SBRA) used in the B-2 fleet. You will be surprised.
The plan for fitting SDBs onto the B-2s called for a maximum of 192 SDBs per aircraft. If four were installed on each station of each rotary launcher, the maximum would be 4*8*2 = 64.
The B-2 bomb bay is one of the reasons we see the US standardising weapon sizes. Each B-2 weapon bay is not long enough to fit two 2,000lb JDAM in tandem. This means it can only fit 8 2,000lb JDAM per bay on a rotary launcher giving a maximum of 16 2,000lb bombs. The single B-21 bay is longer and would allow the same 16 bombs in a much smaller bomber.
I find it really hard to imagine swapping in a new rotary launcher or two new racks with all the bombs on them is more time consuming than putting in the bombs one by one...
The rotary launchers use adapters and other racks that offer both 14" and 30" as well as other optional locations. You mount your specific rack to these if needed.
What about NATO members happen to design similar "sizes" since the 70's?
Amusingly, the USAF kept complaining in their report to congress about the B1 needing 24 hours to reload compared to 4-5 or so hours for the B52 as one of the reason they needed the more numerous LRS-B/B21.
The SBRA may fit (the bombs need a bit more than 7m) and 60x 575 lb + 5000= 39500 lb would be a bit more than official admitted.
Pretty sure that won't fit into a B-21. We're looking at something closer to a stretched ASALM for the hypersonic cruise missile.
Unknown at this stage, we don't know the IWB length accurately, or ARRW dimensions for that matter.
