B-52 Heavy Lift ideas?

[MMM]

So, I'm looking to increase the lifting capacity of a B-52- making it capable of carrying TWO X-15s at once. Any ideas for how it should look? What should I do with the wings? Has anyone done this kind of whiff before?

Links to pix (if any) would be helpful.

-M@

[sandiego89]

I would just do a mirror image of the B-52 mothership, in addition to the port launch pylon, add an identical launch pylon on the starboard wing.  The X-15 (without the big tanks) was about 34,000 pounds loaded.  The "big-belly" modification (which despite the name did not increase the size or appearance of the bomb-bay and was not visible to the eye) to the B-52's allowed @60,000 lbs of bombs to be carried, so you are pretty close in overall weight. I made a B-52H into 1/144 mothership that carried a F-104 under each wing postion as a fighter conveyor.  Can try to post a picture later, but the model has suffered from a few drops.     

I do not think you need any major wing or other modifications, but some thoughts:

Other modifications to the real motherships include deleting the tail gun postion, a notch in the flap to allow clearance of the X-15 vertical stabilizer and the flaps were locked in the up position. All bombing and recce gear was stripped out.  A few top off tanks and other gear were added (internal).  A few camera and viewing portals were added.    

You would want more power if using an early B-52. You could go with the "H" model engines for more power. Quite and increase in power over the A-G models.  Or hang 4 large turbofans in place of the 8 engines from a suitable airliner (as we just pondered in another thread) if you want a "different" look.  

Delete the external wing tanks on the B-52 for decreased drag if range is not an issue for your scenario.  

Personally the A-F nose looks better for a mother ship.    

[MMM]

I'm coming back to to work on this project, the XB-52 "Thunderfortress", from a few years back- I've got an old Revell 1/144 B-52, and it's a good thing there's two X-15s in the  Dragon 1/144 model box!

"The XF-15 "HyperSabre" was the first hypersonic endo/exoatmospheric weapons system to be deployed by the Strategic Space Command. A militarized version of the experimental X-15 hypersonic vehicle, the XF-15 allowed the Strategic Air Command to make its first tentative steps into space defense. Eventually, infighting over control of exoatmospheric operations between the Air Force and Navy led to the formation of a separate service, the Strategic Space Command, in 1964.

The XF-15 was only functional as the front line of exoatmospheric defense for a five-year span, from 1961-1966. In 1966, the XF-15 was superceded by the XF-20 (later F-20) DynaHawk, which was designed to be launched from either a Titan III rocket or the back of a B-70. Though rendered obsolete with the introduction of the XF-20, XF-15s and ThunderFortressess were kept on as part of most major U.S. cities' active threat-response defense until 1972. (True SSTO fighters had to wait until 1975, with the deployment of the F-302 Interceptor.)

The XF-15 was rushed into production at the very beginning of what would later be called the First Zork Incursion, as a last-ditch attempt to protect the Earth from what later turned out to be five rogue Zork scout saucers, whose intermittent re-supply raiding parties were launched from a crashed Zork mothership on the far side of the Moon.

Two HyperSabres were carried to altitude under the wings of a XB-52C, the "ThunderFortress". The ThunderFortress gained its nickname from the fearsome sound of its takeoffs; laden with one HyperSabre under each wing, the XB-52C lumbered into the air under the full power of ten jet engines (two additional single-engine pods replaced the outboard fuel tanks), a full set of JATO bottles, and a single, throttleable A-6XV variant rocket engine (which replaced the gunnery position in the tail.) The rocket engine was re-ignited to put the XB-52C into a sixty-degree accelerating climb before release of the two HyperSabres at altitude.

Each XF-15 was armed with two Genie-X nuclear-tipped missile, sheathed in ablative material, carried at the wingtips of the craft. The Genie-X was equipped with both proximity and radio-controlled remote detonation triggers, and could be detonated on command by the XF-15 pilot.

During their lifespan of deployment, the XF-15 shot down or otherwise disabled three of the Zork scout saucers. Much was learned from the Zork debris, including important clues towards the advancement of gravity generation and fusion technology. Seven XF-15s were lost during this same period, including two that were brought down (along with their XB-52C mothership) by a suicidal Zork scout saucer.

During the 1974 Zork Incursion, there was some discussion about returning the XF-15 to service for the duration of the emergency. Instead, the XF-302 was brought on-line early, before final tests were complete."

[sandiego89]

Well, that is an interesting back story!  I like the proposed modifications to the B-52 mothership.  For a closer to earth backstory, the Genie equipped XF-15's could also be set to intercept inbound Soviet bombers over the arctic circle. 

[KJ_Lesnick]

MMM

You would just need to add the extra pylon (a mirror image).  The rest would be fine for the following reasons

1.) The bomb-load for the plane was 43,000 pounds originally; it however was physically capable of carrying more 17,000 pounds more it would seem -- It had to do with the bomb-shackles, the bay didn't change in size
2.) When external pylons were added the maximum load went up as high as 75,000 pounds (2 x 34,000 pound vehicles would be 68,000 pounds)
3.) Maximum takeoff load isn't the same as the maximum structural load the wings can take

The last one sounds counter-intuitive but think of this way: If you're pulling 2.5g you're producing 2.5 times the lift of the plane.  Even an early B-52 which had a MTOW of 420,000 would therefore have a maximum structural load limit of 1,050,000 pounds.

The takeoff limits usually are based around a bunch of other facts which are very important

- The weight the gears can hold routinely without buckling
- The weight the gears can hold and not buckle period
- Takeoff run
- Controllability with an outboard engine failure
- Ability to climb reasonably well
- Ability to climb with an engine dead
- Ability to maneuver in a remotely purposeful way

With 68,000 pounds of extra weight you might be fine and if not you just remove a tiny bit of fuel, refuel right after takeoff and then keep on going: The B-52 has the various means of staying aloft a long time (multiple crew, a toilet, etc) so basically you can refuel over and over again and stay airborne for probably a few days or weeks provided the crew have enough food and blue water to crap into and you don't get engine failures.

You keep 'em in the air in the event some kind of threat comes on it's way and pop those two babies off, they race up in altitude and speed pop off the genies and glide in.  One thing I can think about would be pulling off a successful immelman which is used for nuke release (pull up until you're upside down, then half roll the plane): You don't want to be going in the same direction the weapon is when it goes off.  

If you're in space you can use the plane's RCS motors to point you up but without air-resistance you'll keep shooting forward -- with thrust from the engines you'll go up but still shoot forward as well.  On the bright side the enormous speed from the X-15 would be imparted to the missile so you'd just have to slow yourself down enough that the weapon would get far enough from you and blow up.  I suppose you could basically use the RCS to pitch you so your tail end is pointing towards the missile, fire your main engines if you got any fuel in them and burn until you're practically out of gas as it races ahead and blows up, then use the RCS to flip you forward and then re-enter.  

The problem is you need to enter the atmosphere without burning up.  You'll accelerate on the way down and that's fine as gravity does it's thing but as you pick up enough speed you could run the risk of burning up so you'd have to then adjust the pitch nose up to produce the correct re-entry angle.

Spaceflight isn't as easy as Star Trek and Star Wars makes it out...

[Captain Canada]

Put a great big honkin' Orenda 14 on the rear fuselage like the B-47 that was leased to the RCAF for the Arrow engine trials......then she'll lift anything !