C 130 tank drop / cg shift?

SixPapaCharlie

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when A C 130 is flying low and dropping tanks out the back, how do they handle the rapid shift in center of gravity?
 
Dumping 3,000lbs worth of jumpers out of a caravan doesn't really cause much of a issue, I'd imagine the C130 would be similar just scaled up.
 
Dumping 3,000lbs worth of jumpers out of a caravan doesn't really cause much of a issue, I'd imagine the C130 would be similar just scaled up.

In the caravan, they start in the cabin and exit through the side of the cabin, meaning a relatively small CG change. In the -130, the loads shift aft, then go out the back ramp. Big CG change there, all the way up to a 20K lb load going out the back...
 
Maybe some sort off counter weight on rollers that goes the opposite direction when large amounts of weight go back?
 
Maybe some sort off counter weight on rollers that goes the opposite direction when large amounts of weight go back?

Far too inefficient. C-130s go into and out of very small strips and I imagine that would only slow them down, complicate the issue, and cost a lot of fuel.
 
when A C 130 is flying low and dropping tanks out the back, how do they handle the rapid shift in center of gravity?

It's rapid....like you state....but the CG might only be off for a few seconds...they train for it. Not really as complicated as u think it might be.
 
Look where the cargo door is relative to the tail. That's probably by design, yes? These days the C-17 is doing the heavy lifting.
 
when A C 130 is flying low and dropping tanks out the back, how do they handle the rapid shift in center of gravity?

I would imagine through the use of their biofeedback controls pushing then pulling on the yoke.
 
I would imagine through the use of their biofeedback controls pushing then pulling on the yoke.

Are you yoking or being serious?

I imagine Henning....biofeedback contemplating use of jet a...wtf am I doing here....superpowers getting richer while I'm at the controls, society should have taken a different path.......

CFIT INTO THE GROUND......:yikes:

Kidding Henning...;)
 
Are you yoking or being serious?

I imagine Henning....biofeedback contemplating use of jet a...wtf am I doing here....superpowers getting richer while I'm at the controls, society should have taken a different path.......

CFIT INTO THE GROUND......:yikes:

Kidding Henning...;)

It means you use your eyeballs to judge your AOA and use your arms to work the yoke.
 
It means you use your eyeballs to judge your AOA and use your arms to work the yoke.

Yes our military is trained wonderfully......best pilots out there.....I'm sure we can agree with this. Even if we can't agree on the mission.
 
Intersting you should ask because over the weekend, two C-17's over the pacific dropped two ballistic missiles on pallets that decended on parachutes and then launched towards Wake island for testing missile defense. The C-17's are at 25000 feet flying near stall speed. When the ~70k pounds goes out the back the CG shifts allot and as Henning says, the pilots hold on to their seats with their sphinctor and push to prevent a stall. Nothing magical, just good timing and crew communication.
 
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I've jumped out of C130's, and I've ridden in the back of a 141 dropping a huge pallet, and I've never felt a perceptible change in deck angle in either case.
 
C-130s aren't carrying Sheridans anymore so you're looking at APCs and Humvees. Several vids online you can see the tail pitch down and then up as the load goes out the door. I would imagine if the pilot made no compensation the angle would be more noticeable.
 
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The loadmaster runs a before and after drop CG calculation to make sure the CG will stay within limits. Pilots say the extraction is quick and the pitch change isn't that much, it is easily correctable with a bit of forward pressure.

Source: Just asked two C-130 pilots.
 
The remaining passengers all jump at the same time the load is dumped. The loadmaster coordinates this. This is how they did it at moody
 
The remaining passengers all jump at the same time the load is dumped. The loadmaster coordinates this. This is how they did it at moody

Do you stage them at the front to use the reaction of their down force, or in the back for the relief?:confused::lol:
 
Push, push, push as the tank rolls aft then pull when the pressure is released. It's a big airplane and the tank goes out fast.
 
Re: C 130 tank drop / cg shift

Was a loadmaster,
On C130s ,been there done that. No big deal on the weight shift. So long as the load doesn't get hung up.
 
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Do you stage them at the front to use the reaction of their down force, or in the back for the relief?:confused::lol:

I remember the loadmaster making us scuttle butt to the front. Weird way to do things but it worked I guess
 
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