Stratolaunch’s air-launch system is designed to carry multiple rockets up to an altitude of about 40,000 feet, and then drop them into the air to fire up their rocket engines. The advantage of such a system is that it can take off from any runway that’s long enough to accommodate the plane, fly around bad weather if need be, and launch a satellite into any orbital inclination.
That bugger is almost surreal. The stresses that that middle wing section must be able to handle still boggles my mind.
I wonder which cockpit the crew sits in?
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If the designers are worth their salt, both cockpits will be fully functional and fully manned. (I am a redundancy freak!)
A good boat would always have at least to drive engines, three generators, multiple radios, dual navigation systems, dual radar systems and dual spotlights.
Historically twin boom and twin fuselage aircraft are incredibly strong.
The wing load would be more of a concern to me.
Historically, twin boom and twin fuselage aircraft were several orders of magnitude smaller (think dynamic inertial forces) and were connected at the tail with a single elevator, which minimized differential torque between the two hulls. And they didn’t carry 275 tons suspended on the wing between the two fuselages.
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Perhaps, but a fully equipped flight deck is not cheap, and a failure so complete that that level of redundancy was required to save the aircraft is rather unimaginable.
My guess is that the second flight deck area is used for the launch engineers.
This is true but some of them certainly carried extremely heavy bomb loads for their size.
The central wing surfaces have a whole lot of bracing and are anchored on both ends. The outer wings have only one contact point carrying half the load of the entire aircraft each.
The wing structure is continuous from wing tip to wing tip with the fuselages hung from it. They are not attached to the outside of the plane (like a super cub.)
My guess is that the wing from one set of engines to the other is essentially a structural beam, designed not only to carry the immense weight, but also to resist the tendency of the two fuselages to move independently of each other. This is not a long range aircraft, so they don’t need the wing space to store fuel. Besides, they have a considerable volume in those two hulls to store more fuel … probably enough to fly nonstop around the world a couple of times.
Satellites with rockets attached are not cheap either. Neither is the cost of placing them in orbit via ground launched rockets. …and the benefit of choosing the plane of the orbit relative to the polar axis is quite beneficial.
The plane should at least be capable of being flown and landed from either cockpit.
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Yes, I get that. The “wing load” however is highest on the points closest to the fuselage which is why when wings fail that’s usually where they fail because that’s the point of the greatest stress.
A wing span that’s probably longer than the distance the Wright Brothers first flew. Actually not. It’s wing span is just under 400 feet, about half the Wrright Brothers first flight distance. Still.
Like a gun: Better to have it and not need it, than to need it and not have it.
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I have designed electrical systems for several Mississippi River tow boats ranging in size from small local barge movers to large long haulers. None of my designs had fewer than two matched generators. Many had two matched generators and a third smaller generator switched to handle only the essential system functions. Some had three matched generators.
My emergency lighting systems utilized a separate 115 volt system with lamps rated for 130 volt operation. This gave them a greater lifespan despite the inherent vibration of the fixtures.
You need a way to tell which nav system is correct if the two are giving different readings.
I love redundancy too.
I once knew a towboat Captain that carried his own personal GPS unit…even though his boat had two Lowrance systems.
However, on the river, it is relatively simple to verify your exact location using navigational maps that show coordinates of landmarks. River boats depend on radar and depth sounders more than GPS systems…that and channel marker buoys. In the air, it’s not possible unless you can see the ground features. On the ocean, you’re out of luck.
I deal with helicopters that fly off of ships. So they are in the air, over the ocean. There are two EGIs ( GPS combined with inertial) and one backup based on something… probably magnetic. They are constantly monitored to determine if one of them is not telling the truth. Sometimes you can tell which one is lying. But sometimes you can’t. Those crews have my respect.
They also have two engines and (I think) three generators. Several other systems have redundant backup as well.
I guess you mean LORAN. Interesting article here.
GPS jamming is a big deal. The military is prepared… kinda. Not sure about the rest of us though. I can find the north star. That’s about it.
I actually, I meant Lowrance (brand name) systems. Likely they were LORAN…acquisition of location based upon ground source radio signals rather than satellites. I had one in my truck for a long while.
I’m not following what that has to do with my post. I know all about designing a beam to accommodate the stresses that it is expected to be subjected to. That in no way changes what I said about the dynamic stresses that the center section will be subjected to in flight due to the independent motion of the fuselages. Those forces in this aircraft will be unlike those experienced by any previously flown twin fuselage aircraft.
Wing load, by the way, is defined as the pounds per square area of the wing under load. It has nothing to do with the torsional and shear stresses I am talking about.
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Perhaps you could research it and find out if indeed that is the case.
My question remains in either case … which case cockpit is the plane flown from? Traditionally, the left seat is occupied by the pilot in command. I am simply wondering if that tradition carries over to the left flight deck.