Physical size, volume and weight capacity of the internal bays does matter, but the configuration and internal attachment points are also important.
The B-2 has 80 attachment points for the BRU-61/A SDB rack, I don't know how many the B-1B has, some figures I've seen say 96-144 SDB's for the
Uhhhh, no. This is a photo of the BRU-61 SMER in a B-2 weapons bay-
As you can see, it's 8 per rotary and thus 16 per jet which equates to a maximum of 64 GBU-39.
I frankly don't know where they came up with the '216' number. As that is on the order of 66,000lbs in munitions alone and the Batarangs maximum
payload metric is in the low 40s. A fully loaded BRU-61 with four GBU-39 aboard runs about 1,600lbs so either they planned on a CBM type (large
scale) rack. Or the 216 is based on a false understanding of how the payload:weight issues are truly resolved.
In any case, the big differences to keep in mind here are as follows:
1. Despite 'promises to the contrary' (expeditionary inflateable hangars and the like) the B-2 continues to fly almost entirely out of Whiteman AFB
in Missouri. Which means that you are looking at 40+ hour trips to the ME/SWA region.
2. An F-15E is seldom more than about 8hrs out from any target it can realistically be expected to reach, just on the sheer un-comfort factor of
sitting on those damn ACES II. The longest I recall hearing of was a single flight from Dharan to Kabul that was about 17hrs and they had to peel the
pilot/WSO out with a blotter at the end of it.
3. If you end up paying 'X4' (due to nascent corruption) for something to be rebuilt after you blow it up, it makes sense to /deny it temporarily/
rather than hit high value targets that cost a lot more to replace. U.S. Desert Storm tacair idiots being a case point where the "Ho Boyee Big
Building!" effect was what they aimed for in blowing up turbine generator halls rather than transformer pads and powerline distribution junctions.
Partly this was because they just couldn't see anything much smaller. Partly it was because the weather and the enemy were all making life
complicated. And mostly it was just little-boy-make-big-boom psychology. But if you /can/ attack individual point targets, be they loading ramps and
approach roads to a Yugo factory or the pumps at a cracking tower, you can still blackmail the local yokels into seeing their bank accounts go flat
without having to _literally_ destroy the infrastructure on which the 'next government' will still depend to keep their city-state from defaulting
on multiple loans.
4. As someone else stated, the ability to stand off is important. Right now, even from 50,000ft, the B-2 is /terribly/ vulnerable as a more or less
laydown-as-target-overflight type bomber. Indeed, at operational heights and speeds, it may well take 20 miles to turn a bomber around in and this,
when combined with the changes in radar observation aspects may well put you in a damned-if-do-thrashed-if-don't scenario whereby the threat WILL SEE
YOU BEFORE IMPACT if you maintain current course. But they will also track you if you try to 'break away' (which is particularly difficult in the
Spirit because GTW mode halves the control deflection authorities). Indeed, if anything, the adoption of the GBU-39 may signal an acknowledgment of
what Rumsfield I think it was admitted way back in 2000 when he came back from Russia with the news that "Yes, they can track us...". Standoff as
_Better Bullet Theory_ is now driving the threshold to which stealth can usefully perform.
Probably the critical factor here is that the GBU-39, when allowed full spectrum use -with it's parent or a remote targeting platform- undertake to
reduce TLE or Target Location Error factors by differential compensation over a 2-way datalink. For the B-2, such a continuous emission would be
death and while I have no doubt that it can do better (with it's GATS system and ultrahigh resolution APQ-181) at 'zeroing' the satellite
propogation errors as stereo bias before launch, it remains true that the majority of GBU-39 use, especially in the later spiral upgrades, will be
against _tactical_ targets developed on a time-critical basis. Such is something that the B-2 cannot really contribute to and probably (HDLD) never
As such, you need a functional UCAV which may only have 8 bombs onboard but which can loiter for 4-6 hours at 700nm radii and just /cover/ a country
with airpower as both a bombardment and mosaic ISR system.
Something which neither the B-2 nor the Fastmover community can match.
Of course we're saddled and ridden by the worthless flyboys so when and if this will ever realisitically happen is attributable solely to the
development and proliferation of DEWS as skyknight killers.