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...all they ever do is bend and break stuff and they should only be computer operated.
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Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut. -
Why do I suspect there's more to this story than just "Captain fu*kup misused the rudder pedals"?
The generic C130 has been around for a heck of a long time and I'd expect any "quirks" in this area to be pretty well known. Maybe the changes to this aircraft put the CG in a bad spot or something?Be alert! America needs more lerts.
Eric Law -
Bear in mind that this was not a normal flight. It was a test flight where they were putting the plane at the limits of its envelope. They lost control of the plane, which at a point became inverted, and the recovery was less smooth that it should. That's where they damaged it.Originally posted by elaw View Post
As I understand it the incorrect use of the rudder is what triggered the loss of control, not what caused the damage itself.
--- Judge what is said by the merits of what is said, not by the credentials of who said it. ---
--- Defend what you say with arguments, not by imposing your credentials ---Comment
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Fair enough... but considering the plane's been flying for 60+ years and has more variants than Beanie Babies, it must have seen quite a bit of test flying before!
On the other hand, I guess sometimes "stuff" just happens...Be alert! America needs more lerts.
Eric LawComment
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Absolutely not!! This is what test-pilot training is for. It's nice to know the military is lumping all the cash into R&D and not enough into S&R (Stick & Rudder). Oh well, scratch one of only sixteen AC130J and taxpayer money that could have been used to build a school of fix a bridge or train an air wing on the use of rudder and unusual attitudes recovery, especially for test pilots pushing the envelope. I'm also wondering where the AoA was when they did this...Originally posted by Foxtrot AlphaComment
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Probably varying.Originally posted by Evan View PostLes règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.Comment
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there you go again! do you really believe the military yanks any old jerk of the flight line and designates them a test pilot???? do you really believe that even after 6,000,000 hours of teaching, practice, and testing even the BEST DAMN PILOT IN THE UNIVERSE wont make a mistake?Originally posted by Evan View Post
Although losing a brand new, low density-high demand asset like an AC-130J is bad news, this is what testing is for. Better have a permanently grounded plane than one laying on the ground burning in the enemy’s backyard.Comment
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Why bother TeeVee, I am sure this was a problem with the center wing fuel tank!Originally posted by TeeVee View Post
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Really?Originally posted by TeeVee View PostInvestigators have attributed the incident to the pilot’s “excessive rudder input during the test point, followed by inadequate rudder input to initiate a timely recovery from high angle of sideslip due to over-controlled/under-controlled aircraft,” along with the “wrong choice of action during an operation.”
No, TeeVee, I don't think the military "yanks any old jerk of the flight line and designates them a test pilot". An envelope-pushing test pilot must be very practiced at recovery and very prepared to lose control. That's what makes this so much less excusable than the average Renslow affair.
So, was it the pilots fault? Actually not entirely, because they were given...
...poor procedural guidance and publications for the test team to follow.
Brilliant. If that doesn't get you a bit angry as a taxpayer, just remember that you're going to pay for this, not them.
Test flights are to determine design issues, flight control issues and pilot-interface issues. There may have been a pilot-interface issue here as a contributing factor but that's what test pilots are for.
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Um... since the pilots presumably reside and clearly work in the USA, they're going to pay for this as much as you and I am.Originally posted by Evan View PostBe alert! America needs more lerts.
Eric LawComment
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Please excuse the stupid question, but I don't understand what "that" stands for, both where the article says "that is what testing is for" and when Evan says "that is what test pilots are for".
Is it bending planes, loosing control, screwing the recovery, or losing a brand new, low density-high demand asset like an AC-130J what the testing and/or test pilots are for?
The line in the article is particularly convincing that it is the latest option:
Although losing a brand new, low density-high demand asset like an AC-130J is bad news, this is what testing is for
--- Judge what is said by the merits of what is said, not by the credentials of who said it. ---
--- Defend what you say with arguments, not by imposing your credentials ---Comment
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I wish I knew more what this means. Airplanes usually take care of themselves and generally do what they are supposed to do in response to control inputs.Originally posted by Gabriel View Post
Indeed, when stalling and spinning, the controls may not work "normally", but conversely, planes generally do the same thing, and short of that aerobatic maneuver called a Lomcevak or a flat spin, the big tail thingie keeps the pointed end going forward and the wings and dihedral and ailerons work to keep the greasy side down.
I guess I'm saying did they really "lose" control, or did they outright "over" control, get it upside down...I'm thinking the second may be more correct.
I'm also thinking some C-130- (and/or pilot-) bashing is in order given the nice barrel roll that was once done in a 707 and it lived to fly another day (as did it's pilot).Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.Comment
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In my post, ""that is what test pilots are for", 'that' specifically refers to the identification of pilot interface issues that could degrade SA and lead to loss of control by non-vigilant, non-test pilots. That is, assuming the test pilots were properly familiarized with the aircraft before the test flight, which in this case, doesn't appear to be the case.Originally posted by Gabriel View Post
On other words, test flights are not for bending planes. They are for finding limits, identifying incipient issues and taking action before the bad stuff happens or recovering before the worst stuff happens.
They are not for discovering how well a crew can control an aircraft without the proper guidance and manuals.Comment
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They usually do in normal attitudes. When you get into a slip in a power-on scenario (I think we can assume a commanded slip in level flight is a power-on scenario) you will get some degree of rudder float, increasing from the neutral position with the increase in slip angle. Therefore, as the slip angle increases, the pilot has to apply less pedal force to maintain the angle and the angle also begins to swing out at a faster rate. Eventually it reaches a point where the rudder angle needed to maintain the slip and the rudder float meet. At that point you can maintain the slip with no pedal pressure at all. Beyond that however, you get into rudder force reversal... this is where you must maintain opposite pedal force against the slip to maintain it. If you fail to do this, you will get into extreme slip angles, a nose-up pitching tendency, AoA issues and a wing stall / spiral / public-funded military asset writeoff... all rather quickly.Originally posted by 3WE View Post
Ahh, but wait. As a test pilot on a transport like the C-130, you are going to feel the rudder float issue very well in advance, then you are going to get obvious fin buffet well before reaching rudder force reversal. The threshold of rudder force reversal is also beyond the sideslip angle allowed in the flight manual. So in order to reach this scenario, you have to ignore some warning signs that should be very obvious to a well-trained test pilot. If the pilot is not well-trained on the phenomena (and no line pilot will ever experience rudder-force reversal in the normal envelope, unless possible in severe wake turbulence—and in wake turbulence you should NOT be trained to use rudder as described above as the rudder will return to neutral on its own after passing through the momentary turbulence), the counter-intuitive need to add opposing pedal force in a slip/skid manuever might cause a loss of SA, prevent proper recovery and quickly lead to stall/loss of control.
That's all based on what I know of the C-130 in general and perhaps the AC-130J has some modifications that effect the onset parameters (such as twice the power?) and I'm not saying this is what happened here, I'm merely illustrating the difference in skill and knowledge that a test pilot who is pushing to boundaries must possess. In other words, that's what test pilots are for.Comment
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Is it written somewhere that maneuvers performed by test pilots should always progress as predicted in advance and have a happy outcome? My understanding of tests like these are that they're often performed to find out where "the edge of the envelope" is, and if you never go past that edge, how exactly do you know where it is?
Or in other words, there can be a pretty fine line between "the pilot effed up and damaged the airplane" and "the design of the airplane was effed up such that the plane did not react the way the pilot expected it to".Be alert! America needs more lerts.
Eric LawComment
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