1st AC-130J is a write off

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This hurts, glad the crew recovered the plane. Even so, losing your first test bird is not good (especially after retiring a bunch of other aircraft). Losing it after encountering the same condition twice isn't awe inspiring.
Maintenance now has a training airframe.

Here is the story via the AF Association:
Investigators declared the first prototype AC-130J Ghostrider gunship a total loss after the airframe was severely overstressed after departing controlled flight during a test sortie from Eglin AFB, Fla., officials announced. As a result of the incident, "the mishap aircraft exceeded its design limit load to an extent that rendered it unsafe for flight and is considered a total loss to the Air Force," according to Air Force Materiel Command's Accident Investigation Board report, released on Nov. 6. The crew was performing a high-angle, side-slip at Eglin AFB, Fla., during handling tests of the developmental gunship when the aircraft departed controlled flight at 15,000 feet over the Gulf of Mexico, according to the AIB. The AC-130J "tumbled inverted" before test pilots were able to recover controlled flight, entering a vertical dive, on April 21. The aircraft lost 5,000 feet altitude, pulled 3.19 Gs, and oversped the flaps' maximum allowed airspeed by 100 knots before returning to level flight. The AIB determined the pilot's excessive rudder input and failure to quickly recover from uncontrolled flight were the primary cause of the mishap. Problems with the aircraft's warning system, pilot disorientation, confusion from being hit with unsecured equipment, and inadequate technical guidance also contributed to the mishap. The aircraft, serial number 09-5710, also suffered a similar incident in February, and has been grounded since the April mishap. A second AC-130J prototype was delivered to commence operational testing at nearby Hurlburt Field, Fla., in July. Loss of the aircraft is estimated at $115.6 million. (See also Ghost Rider Gains and Pains from the September issue of Air Force Magazine.)
 
Glad everyone who was on board is ok.

My question would be did the high-angle, side-slip maneuver create the problem or did the crew exceed the parameters of the maneuver?
 
Inverted in a C-130 would have had me shitting in my flightsuit:-o!! The G loading will overstress the wings, and the crew did well to bring her home and land without further problems. It sounds like they went 90 degrees to the ground fell out of lift. It's a shame they could not have gotten the nose down, or wing up, just a bit earlier. It needs to be pointed out, I feel, that these were test pilots, and they do push envelopes from time to time. I am also wondering if the pilot input the attitude, or if the aircraft auto controlls did it to keep "guns on target"? Scary event, and I am glad all got home safely.
 
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Just found this illustration:

AC-130J.jpg
 
Ok... it's the pilot's fault, but the plane has been grounded for 7 months because of the last time this happened. UM, WTF? So, did it actually occur in Feb or Apr? Or...BOTH?

...The aircraft, serial number 09-5710, also suffered a similar incident in February, and has been grounded since the April mishap....
 
Ok... it's the pilot's fault, but the plane has been grounded for 7 months because of the last time this happened. UM, WTF? So, did it actually occur in Feb or Apr? Or...BOTH?

...The aircraft, serial number 09-5710, also suffered a similar incident in February, and has been grounded since the April mishap....
Two incidents, my guess is the second incident happened trying to find out why the first incident happened. Hopefully they now know.
 
I looked up a side-slip. It sounds like the crew stalled the plane and it rolled onto its back before going vertical....and in a C-130 that must have caused some soiled flight suits.

The Dangers of the Sideslip in Light Aircraft

Simply put, a sideslip is an uncoordinated (yet stable) condition of flight where crossed controls (opposite aileron and rudder input) increases drag and allows the pilot to fly a higher rate of descent with a constant airspeed.

Because of the increase in total drag, your airspeed while flying a sideslip will rapidly reduce. Appropriate pressure on your control column is then necessary to maintain airspeed, thus increasing your rate-of-descent.

Stalling speed during a slip will increase for two main reasons. First, you’re increasing the angle of attack on multiple control surfaces. Second, you’re altering the flying characteristics of the aircraft and yielding unknown aerodynamic consequences. You’ll have an increased stall speed, decreased flying speed (due to increased drag) with ‘challenging’ handling characteristics.

Now the AF has to figure out why this happened twice.
 
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Knowing a bit more about the situation, and having talked with both mishap crews, it's deceptive to claim pilot error.

Part of the fault is on the design of high powered propeller aircraft. The rotation of the props cause a gyroscope effect that naturally wants to pitch the plane nose down, and roll it left wing down. I have been taught this and experienced it many times in the simulator. Add in the smarts of the J model, that senses it is stalling and adds power to save itself, and suddenly in a left hand turn, the right wing suddenly has massive amounts of lift, due to the blown wing design of the -130. This causes the right wing to lift even more, taking the bank to extreme, and in this case, nearly unrecoverable angles.

The J model, so far, is less than ideal as a gunship platform.
 
I've only used a side slip to lose altitude without gaining airspeed when playing around in an aerobatic plane. It's quite a ride in a plane built for unusual attitudes when you lose control, so I can't even imagine the people and shit flying around inside a C130. I wonder if they were practicing some sort of tactical approach and stalled the airflow over the rudder and elevators losing most of the controls surfaces used in the slip.
 
Absolutely. With that hunky-chunky airframe, it's like a giant shoebox with wings. $115- million in damage and they walked away.
It certainly looks like a shoebox with wings but it's surprising more agile than it appears:
C-130 Performs Extreme Demo

They were test pilots and searching for the limits of the aircraft (they had a waiver to perform the sideslips) but still...friggin' "tumble inverted" into a near vertical dive from 15,000. No thanks. Losing "only" 5,000 ft in an airplane that size is kind of impressive. And being a test pilot and doing that is one thing but they had a LM onboard as well. Poor bastard. Now, that would suck! LOL.

Here is the full accident report:
http://www.airforcemag.com/AircraftAccidentReports/Documents/2015/042115_AC130J_Eglin.pdf
 
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Knowing a bit more about the situation, and having talked with both mishap crews, it's deceptive to claim pilot error.

Part of the fault is on the design of high powered propeller aircraft. The rotation of the props cause a gyroscope effect that naturally wants to pitch the plane nose down, and roll it left wing down. I have been taught this and experienced it many times in the simulator. Add in the smarts of the J model, that senses it is stalling and adds power to save itself, and suddenly in a left hand turn, the right wing suddenly has massive amounts of lift, due to the blown wing design of the -130. This causes the right wing to lift even more, taking the bank to extreme, and in this case, nearly unrecoverable angles.

The J model, so far, is less than ideal as a gunship platform.
Funny you say that.
My son is a Loadmaster and said essentially what you said.
 
The pilots were test pilots, and when you get right down to it, they did their job, and did it well. They are expected to push the envelope, and in this case did so.Why the side slip? If you look at the mission of the aircraft, and crew, it is to rain lead down on a ground target. The typical flight mode is to point the wing at the target, and let fly with the guns on board, as the aircraft rotates/orbits around the target. Changes in the aircraft angle of attack changes with wind conditions, and a few other factors as well. The question of side slip, to some degree, has to be there every time. It could me a function of cross winds, target movement, and even an aircraft avoidance change in direction. The latter was a factor in Southeast Asia, according to an AC-130 Gunship Aircraft Commander I spoke with @ the Air University in 1975. He had more than one F-4 mess up some of his flightsuits (green bags). This is the first time I have heard of an inverted C-130. In the side slip, rudder inputs turn into altitude inputs, and not left or right in puts. This probably had something to do with the aircraft going inverted, and the strong oder of fecees within the aircraft. Test Pilot error? Prolly so, but we have learned a lot about the J model's limits as a result. In terms of information about the C-130J configuration, and flying characteristics, the test pilots learned a great deal that day. They did a great job in bringing the aircraft and crew back home safely.
 
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