Northrop Grumman B-21 Raider (LRS-B)

donnage99 said:
I wonder if them cat ears aux intakes also provide some yaw stability much like the landing gear door of the j-36 a in low speed.

Edit: nvm just looked at side view, way too small. The unusual elongated piece probably have more to do with low frequency RCS management.
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Actually I think B-2’s main gear doors also provided yaw stability, so it’s reasonable to imagine B-21’s main gear doors have similar purpose…? As of the aux intakes, their elongated shape are probably just designed so that their leading edges line up with the wing’s leading edge…
 
Sweetman/Picarella have updated drawings long ago after B-21 maiden flight. Still out of correct dimensions though.
https://aviationweek.com/defense/aircraft-propulsion/b-21-raider-designed-low-risk.Aircraft wingspan could have been calculated with much more certainty after maiden flight as wheelbase and track was known after rollout. Sat photo just confirmed calculations.
All that was discussed in this same thread many times before.
 

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JoshuaH said:
The Wiki value is directly quoted from AW&ST, which didn’t even get the planform angle correctly…(I would be very, very surprised if the trailing edges are not parallel with the leading edges)
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Yeah, I'm not willing to believe that the inner trailing edges are not parallel to the opposite side leading edges.

Also, I don't think that the AvLeak estimate gives enough length for a 21ft (minimum size) bomb bay. (Note that I still think the bomb bay is closer to 28ft long than 21ft long, but a bay able to hold GBU-57s as well as whatever size the LRSO ends up being is the minimum size)
 
JoshuaH said:
The Wiki value is directly quoted from AW&ST, which didn’t even get the planform angle correctly…(I would be very, very surprised if the trailing edges are not parallel with the leading edges)
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Yeah, I thought AW&ST would be more…definitive. But I have not read it regularly since I got it from my local library as a kid; perhaps it has gone down hill.
 
Scott Kenny said:
Yeah, I'm not willing to believe that the inner trailing edges are not parallel to the opposite side leading edges.

Also, I don't think that the AvLeak estimate gives enough length for a 21ft (minimum size) bomb bay. (Note that I still think the bomb bay is closer to 28ft long than 21ft long, but a bay able to hold GBU-57s as well as whatever size the LRSO ends up being is the minimum size)
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I believe calculations in this thread put the bomb bay at ~24 feet.
 
Byeman said:
the production rate for Sentinel doesn't need to be increased. Still got missiles in the ground. Also, useless without converted or new silos.

Also so predictable response.
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I was about to say, unless the US procures more Silos or TELs more Sentinels don't really make much sense.

More B-21s obviously do, after all it will be the backbone of US strategic aviation. Getting those numbers up is important.
 
Byeman said:
the production rate for Sentinel doesn't need to be increased. Still got missiles in the ground. Also, useless without converted or new silos.

Also so predictable response.
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Still have bombers at air bases.

Plus it’s obviously implied that you’d speed up the silo/infrastructure modernization to be able to put the new missiles in the ground at the increased build rate.
 
With this excellent quote:
Deptula said a modern stealth aircraft operates with “an associated set of other mission assets that employ real-time effects using advanced electronic warfare, cyber, space effects, and kinetics.” It is in combination wiith these that stealth is most effective.

“Add that up and factor in the dynamic variables of combat and it’s quite formidable,” he said. “Detection is but one element of a series of actions that must be taken to defend against stealth. After detection, the low-observable target must be tracked, the track must be transferred to an interceptor, then to a weapon, then to a fuse, and the fuse must be properly designed for the target. Each one of these elements in the kill chain are complicated by stealth, which decreases the probability of intercept.”
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But one day, maybe, although the alleged detection by the Kilowatt would be... Hum, embarrassing.
 
Maybe this is already addressed, but with a nose like that, where is the radar on B-21? or B-2 for that matter. could it be 2 rectangular arrays on either side of the nose under the cheek? it needs to see the ground and the air. how though?
it would also make sense to have a radar in the rear for self defense.
 
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Rearward firing air to air missiles and radar would be a good idea for the B-21 Edwoooo, it would be better than the B-2 having no defence at all and just relying on just it's stealth.
 
FighterJock said:
Rearward firing air to air missiles and radar would be a good idea for the B-21 Edwoooo, it would be better than the B-2 having no defence at all and just relying on just it's stealth.
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B-2 was originally specified to carry the AMRAAM, but SAC dropped the requirement sometime back in 1983-4. I don't recall that they said why.
 
kmrumble said:
B-2 was originally specified to carry the AMRAAM, but SAC dropped the requirement sometime back in 1983-4. I don't recall that they said why.
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They also looked at putting AIM-120s on the pylons between the engine nacelles on the B-52. At least one B-52 pilot (BUFDRV on F-16.net) was not crazy about the idea.
 
FighterJock said:
Rearward firing air to air missiles and radar would be a good idea for the B-21 Edwoooo, it would be better than the B-2 having no defence at all and just relying on just it's stealth.
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Like Firefox from 1979, you must think in Russian, you cannot transpose in English. Firefox had a rear firing defense pod.
 
That would have been crazy puting the AMRAAM onto the B-2 kmrumble, but I suppose that it could have worked in principle if the USAF were serious enough to do it as the B-2.
 
FighterJock said:
Rearward firing air to air missiles and radar would be a good idea for the B-21 Edwoooo, it would be better than the B-2 having no defence at all and just relying on just it's stealth.
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I don't know why we don't design combat planes with rear facing radars.
 
Perhaps it would not be like that Sferrin as those rear facing radars would have frequency jumping capabilities a bit like the front radar on the B-2.
 
FighterJock said:
Perhaps it would not be like that Sferrin as those rear facing radars would have frequency jumping capabilities a bit like the front radar on the B-2.
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Is there such a thing as a broadband detector?
 
Most aircraft lack the volume for any significant radar installation after, and even in larger aircraft that do, there is of course a cost in SWaP-C on top of financial.

It would not surprise me if B-21 did have some kinda of rear facing radar arrangement on the diamondback tail - there would be room for at least small units if not a matching set to the frontal arrays. Modern AESA is so versatile there would be a lot of advantages to being able to emit in 360 degrees even if A2A was not considered. Jamming, SAR, ISAR, NCTR, etc. I could also see it being useful to not have to perform a major course change to bring a sensor to bare for a stealth aircraft inside enemy airspace.
 
Sferrin said:
May as well be saying, "here kitty, kitty" to enemy missiles.
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Missiles homing on the radar is much less of an issue these days, when radar is not just a dumb component that pings at a constant rate. If the rear-facing radar notices a missile aiming directly for the plane, it can stop painting it.
Edwoooo said:
I don't know why we don't design combat planes with rear facing radars.
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Radar (and it's supporting components) is one of the most expensive parts of the plane. Side panels for AESA (which would extend radar coverage almost to a full sphere) are proposed for almost every new fighter now, and then left off when people realize that they'd rather have 4 planes with a forward facing radar than 3 with full coverage. This calculus can be different for a very expensive bomber than it is for a fighter.
 
Tuna said:
Missiles homing on the radar is much less of an issue these days, when radar is not just a dumb component that pings at a constant rate. If the rear-facing radar notices a missile aiming directly for the plane, it can stop painting it.
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Still, seems like a good way to let everybody know someone is around. Like a thief sneezing in a house they'd just broken into. It might be dark, he might be quiet now, but you know somebody is there.

Tuna said:
Radar (and it's supporting components) is one of the most expensive parts of the plane. Side panels for AESA (which would extend radar coverage almost to a full sphere) are proposed for almost every new fighter now, and then left off when people realize that they'd rather have 4 planes with a forward facing radar than 3 with full coverage. This calculus can be different for a very expensive bomber than it is for a fighter.
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Yep. The F-22 has two empty spots (three, if you count the one for the never-installed IRST).
 
I am guessing that there are radar warning receivers even now?
 
Foo Fighter said:
I am guessing that there are radar warning receivers even now?
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Yes, but they are much less useful than they used to be.

In a vacuum with spherical cows, a single plane with a radar will light up your RWR. But that's not the problem on the modern battlefield. The modern battlefield has MALDs (and equivalent), and if US is flying an operation where planes with radars on contest the airspace, every RWR of every plane in flight will be continuously lit up like a Christmas tree. Stealth is not a cloaking device, the purpose is not to be undetectable, it's to be untargetable.
 
This is going to be a bit of a non-sequitur.

I really hope that some of the $425mil AIM-260 development funds the USAF is spending is related to clearing the JATM for B-21.
 
Scott Kenny said:
This is going to be a bit of a non-sequitur.

I really hope that some of the $425mil AIM-260 development funds the USAF is spending is related to clearing the JATM for B-21.
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Unclear it has any place to fire it from.
 

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