KC-135 accident report

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Yeah, I taught it that way because that's what the check airmen wanted to see. More screwed up training that didn't apply in the real world. Then I told them just slow down. Or you could roll into a bank.

Before we drift too far, tailwinds to the crew out of FRU who didn't have a chance to figure this out.
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A lot of times in the EMB-145, we get a rolling back and forth motion w/the airplane. I just kick the yaw trim to one way or another. Seems to work everytime to stop the rolling motion.
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I find it hard to believe that a 11 minute flight had this crew high and fast enough to experience dutch roll to the degree that the tail was ripped off. Can a 135 guy give us some climb performance data? Sounds to me this crew was fighting a major flight control malfunction that caused major stress on the tail. My #1 fear. RIP brothers/sisters
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Quote: A lot of times in the EMB-145, we get a rolling back and forth motion w/the airplane. I just kick the yaw trim to one way or another. Seems to work everytime to stop the rolling motion.
The CV-880 would do that on rotation. You kicked it out with rudder and aileron, if not, you just screwed your way through the sky.
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I was surprised how many pilots got into and couldn't recover from a Dutch Roll condition when teaching high altitude stall recovery in the Simulator...and that was with everything working.

And surprised how many never received training on recognition and recovery...

After that I made time to teach Dutch Roll recovery procedures at high, mid, and low altitudes....Then a student complained to the director of training that this training was unnecessary, and I was told to stop teaching it.... That student lost control on all three upsets until taught the proper techniques....He's AA's problem now thank God.

This Air Force Crew paid the ultimate price because someone cut training costs...God Bless To them and their families.
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The large rudder on the KC-135 could have a great impact on the flight path. It has a large range of movement and, when in the high range of hydraulic assist, it can reach full deflection very quickly. My first Instructor at Castle AFB in 1970 always taught us to "paint" the rudder as required. I was always amazed on preflight when guys would slam it full left and right during the check. 20 years and 6,000 hours in the airplane and I was still a "painter".
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Quote: I find it hard to believe that a 11 minute flight had this crew high and fast enough to experience dutch roll to the degree that the tail was ripped off. Can a 135 guy give us some climb performance data? Sounds to me this crew was fighting a major flight control malfunction that caused major stress on the tail. My #1 fear. RIP brothers/sisters
Your instincts are correct, the rest of the report is out there in Google land. From what I remember reading it, and I'm not a KC-135 guy, there was a circuit breaker or two that were reset and caused a rudder hard over.

Found it.

http://www.abovetopsecret.com/forum/thread968038/pg1
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This was much more than garden variety " Dutch Roll". The yaw damper had a broken part that made it out of sync with its inputs, making the rudder actually accentuate the yaw instead of combatting it. At the end they say the rudder was basically moving rapidly back and forth, uncommanded, and broke the tail off the aircraft. The top of the vert stab was moving something like +/- 8 feet from aircraft centerline when it finally broke.

You can turn off the powered rudder in the Tanker, which would have instantly fixed the problem. But this scenario has never been trained in the sim, and the scenario used in the sim to trigger the Rudder Power Off scenario is a rudder Hardover, not occilating back and forth. The sim didn't even have this type of scenario as a selectable malfunction.


They also found something like 15 checklists that referred to unwanted rudder inputs. Some of the names of these checklist are very similar, such as Rudder Hunting, Rudder Snaking, uncommanded Rudder ( this one contains the boldface Rudder Power Off), yaw damper failure, as well as procedures for combatting Dutch roll, which they were actually doing when the aircraft became divergent.

Personally, in addition to the crew's lack of exposure to the scenario, I think the way the Tankers manuals are written played a part. Every "checklist" and I put that in air quotes, is paragraphs of text, first describing what you have, then it talks about consequences, then maybe it gives you a remedy. They are by far the worst manuals I've seen in my 4 military planes and 3 civilian ones. I've heard that there has been multiple offers to come up with a civilian style QRH, but big blue says it cost too much.
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The CBs on the tanker could get you a little confused also. As I recall the "OFF" position of the powered rudder required power to stay in that position. In a complete loss of electrical power situation it would fail to the high range. There was another CB that allowed it to switch from high to low range depending on flap position. The standard fix (at least when I flew the airplane) for any rudder problem was turn the thing off and then we will sort it out. The OFF switch is on the center console just aft of the throttles. Very easy to reach.
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There were no circuit breakers pulled or pushed on the flight. The plane started yawing back and forth, got into a kind of harmonic where the yaw damper was actually increasing the occilations and broke the vertical stab along with a one of the horizontal stabs off the airplane.

Yes rudder power off or even yaw damper off would have fixed the problem.
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