B2 Bomb Bay Question

Hi all,

I have a question about the B2 Stealth Bomber - more specifically, about the B2's bomb bay. I'll preface this by saying that this is probably a stupid question, as aircraft design is hardly my area of expertise.

It is common knowledge that the B2 achieves its stealth characteristics by both reflecting radar energy away from the source of that energy and by absorbing some of that energy by using Radar Absorbing Materials (RAM). My question is as follows: Understanding that the B2 is designed to avoid detection by radar, why does the B2 have bomb bay doors which open outward (as seen in the pictures linked below)?






Wouldn't this create an unnecessarily large radar signiture when the B2 has the bay doors open - which is right when it is over a target and, persumably, the time when the B2's crew would want their craft to be as stealthy as possible? Is there some mechanical reason that the doors couldn't open up and into the body of the B2 - not straight up, that would require a very large amount of wasted space in the bomb bay, but slid up and along the fuselage a bit?

Ar Yes! good question!
The B-2's bomb bay should be designed as the bomb bay on Siddely Buccaneer. Or the door should be designed as the door on B-24 which also give a lower drag!

Well this is the very problem with stealth bombers currently in service. When they open up their bomb bays it's like lighting up a flare in the middle of the night. Some claim that the open bay doors was one of the reasons why the F-117 was downed a while back.

Thinking about this it would obviously be more logical to make them move inside. The only reason I can think of is that it would reduce the payload or somehow desturb some mechanics inside the plane.

An other wild theory might be that it would desturb the airflow somehow. Pilots flying the P-38 during the 2nd WW couldn't fly with the (side)windows open. Should they have done that the plane would have started ratteling and it would have been impossible to control it.

There is a reason for this for sure. We just don't know what it is. I can hardly believe that engineers who designed the B-2 didn't think about this issue.

I think some of this too has to do with how quickly they can open and close the doors. A mechanism to move the bay door to the side would probably take more time to open and close. Now the fact remains though that if the RCS wasn't hugely affected in the same way as the drop down bay doors affects the RCS then maybe you can deal with a slightly larger RCS for a longer time because its still not as large as the RCS increase of the other option being the drop down bay doors. Its a good point that has crossed my mind before but haven't thought to much about it. I'll see if I can dig anything else up

Found a neat little patent about a rotatry launch with a door design that is trying to address this issue. Oh almost forgot to mention that its a lockheed deisgn.
www.freepatentsonline.com...


[edit on 22/08/06 by Canada_EH]

I do know the bombs (and missiles?) are mounted on a rotary selector so that if a variety of weapons are carried for separate targets. Having the doors retract in side the aircraft would reduce payload, and probably make the whole system very complicated.



Looking at the underside in the plan - its probably complexities with the undercarriage doors that would prevent them from sliding out and side ways. Someone mentioned time for that to happen. That’s what id go with. Also how would you load the beast up when it’s on the tarmac (landing gear down!)

It’s the best compromise.

i would suggest that lockheed have a good long hard look at the RAF Buccaneer

en.wikipedia.org...

before they start claiming rotary bombs bays as there own idea!

more pictures - and you can clearly see the rotating bomb bay!

www.spyflight.co.uk...


and how the RAF do it

www.amcgltd.com...

Within reason it isn't the door operating mechanism, or the way the bomb bay doors open that is the problem, RAM coating's will take care of some of that. The problem is the bloody great hole in the aircraft fuselage that this action creates. Suddenly you have a big reflective hole with lots of non stealthy equipment inside, and in most cases still non stealthy munitions lighting up radar consols like new years eve fire works.

That is why people are trying to develop the kind of bomb bay and rotary launcher designs that Canada EH found.

LEE.

Originally posted by Harlequin
i would suggest that lockheed have a good long hard look at the RAF Buccaneer

en.wikipedia.org...

before they start claiming rotary bombs bays as there own idea!

They aren't claiming it as their own its just their take on the launcher and a more improved/stealthier design to help with the RCS issue. What bothers me though is that even with this filed and the knowledge that this is a problem they still have the F-22 and F-35 with outwards opening doors.

Here is the link again for the patent just so you can understand its a different take on the design.
www.freepatentsonline.com...

[edit on 22/08/06 by Canada_EH]

And in the light of your reply would suggest quite strongly that you read what you link to first.

Preferably, this system includes at least one cover assembly mounted to the rotary launcher for covering the remaining portion of the opening when at least one of the plurality of missile mounting assemblies is aligned with the opening. The rotary launcher cooperates with the plurality of doors to form a portion of the external contour extending completely over the opening.

The piece in bold is to what i refer to.The buccaneer did this 40 years ago.

And because of that one line you claim lockheed is copying the UK design? Honestly I'll agree that the Buc did that and that is was the first to do it all I'm saying is that this is a different take on it. The design is not identical from what I understood of reading through the patent which I did read through before posting. I'm not personally attacking you in anyway or british design which I'm a huge fan of but you can't say oh that uses a wing its a rip off of the wright brother design. If your trying to say the the UK did it first with a rotatry launcher I never said you where wrong anyways. All I was saying is that lockheed has a patented idea thats all.

Sorry for the tone of this post but I dont enjoy being told I dont bother reading or understanding what I'm saying, probably you dont either.

If its the hole, why not have something like rubber fingers (think of a thick sheet of rubber with srtips cut into it) running the length of each side of the bomb bay, meeting in the middle, the bombs would (with a bit of luck!) fall straight through as the fingers are only connected at one end.

It wouldn't elinimate radar reflection, but will reduce it.

Or is this another typically dumb idea of mine?

sort of like a car wash for the bombs throw in a couple of spinning foam brush to ge the bombs nice and shiney before they blow a hole in a bunker. On a serious side I think you would run into problems with the rubber throwing off the bombs freefall and may create a hazard to the plane. Its a neat idea though but I think it has a couple flaws.

[edit on 22/08/06 by Canada_EH]

At the time of the B-2 composites weren't in large use for internal structure. The materials that they had to use were very radar reflective, because of what they were made out of. Putting a RAM coating on them would have cut down on the capacity of the bay, because it would have taken up more room. And if anything hit it (wiring from the launcher, etc) it could damage the RAM and you'd have the same problem you have now.

The whole thing is though that it's kind of a moot point. If you're a SAM operator, and a B-2 pops up on your screen, you're going to have to realize you have a target, slew the missiles around to SEE the target, get a lock on the target, and fire. By the time you do all this, the B-2 has dropped weapons, closed doors, and disappeared again. It's all a matter of reaction time.

Unless your like the F-117 pilot who was told to fly the same root night after night and they already know where to be pointing the SAM. I think the idea of a door that slides horiz flush with the body would be a good option instead of the drop down doors that are used right now. Unless there are measures in place to reduce the doors as they are right now. Or maybe what Zaph is saying is true too that time they are open is just too short to even be a big deal.

A good question I'm not going to lie.

But I will say this, I've heard many times said over and over, the B-2 is only detectable when it's bay doors open, but even then it's far too late for the enemy.

Shattered OUT...

Whiel we are on the subject the nozzle bay doors on the B-2 where resently redesigned and the plan/want to do the same ot other doors on the airframe.

www.wpafb.af.mil...

AFRL's modification will generate an estimated savings of more than $20 million.

Prior to AFRL's redesign and transition effort, B-2 NBD repairs required multiple days and extensive use of costly materials. Focused on improving this situation, the engineering team established procedures for ensuring that the bond between the composite seal and the parent material of the door met all design requirements.

looks like this team is replace the old parts with new ones that are making use of composites.

Woho 10000 point post

[edit on 22/08/06 by Canada_EH]

Originally posted by Canada_EH
Woho 10000 point post

[edit on 22/08/06 by Canada_EH]

Thats a perfect number. Don't make any more posts, otherwise you would ruin it.

I personally think sliding doors would be a good idea myself. In theory it should reduce drag and inprove the stealth qualities of the plane. When you open the bomb bays of a plane, the doors create a right angle which in a stealth plane llike the B-2, increases RCS dramatically.

Tim


[edit on 6/7/2007 by Ghost01]

Look at it this way, the bombs will be released at a point that is most "blind" to the enemy because the USAF knows the deployment of munitions reduces the aircrafts survivability. Careful route planing, quick release and stand off weapons minimize this shortcoming somewhat but they do not eliminate it. Still thought, the enemy has to be scanning that particular sector, detect/track immediately and launch the missile to down the AC. If the distance is long enough the B-2 may be able to react, if not well... If you know the route, timing and distance of the AC you can shoot down VLO AC in this manor (kind of like what the Serbs did to the F-117). If you do not know that information however your chances of accomplishing such a thing in real combat are very little (which is why no B-2's and only one F-117 have ever been shot down). Still, regarding the F-22, in exercises F-22's open their bay doors to simulate a missile launch (in order to make the exercise more realistic) yet we know from the results it has not affected it's effectiveness. IIRC the pneumatic launcher on the F-22 launches the AMRAAM in less than a second.

Stealth pilots are trained to find targets, open doors, and launch weapons in less than 15 seconds. There's no way that any kind of AAA site is going to see them pop up, and shoot at them in that time frame.