0005304: AFM CH-47F explodes on the ground at moderate pitch angles

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Summary	0005304: AFM CH-47F explodes on the ground at moderate pitch angles

Revision	2019-10-03 05:33 by Shuffl3
Description	The Huron rotorlib port works good and is good fun for me aside from the settings of the ground contact points which have caused some troublish issues, namely... 1.Spontaneous and catastrophic explosions while in/near contact with the ground at over 0000004:0000012 pitch: This seems due to the "tail tip" contact point invisibly extending outside the bounds of the airframe by a meter or two from the cargo ramp. At moderate pitch angles this "virtual tail" strikes the ground and triggers a sudden unplanned disassembly. Moving this contact point inward to the hinge of the ramp should prevent this from occuring and change the overpitching failuremode to a bladestrike. 2. Wierdish taxi behavior: CH-47Fs steer with their rear wheel(s) like a forklift. Swapping the <Features...> and <SteeringController...> between the front and rear wheels and setting inverserotation to true should fix that. I also noticed that the left and right front wheels are offset from each other? Kinda wierd.

Revision	2019-10-03 05:34 by Shuffl3
Description	The Huron rotorlib port works good and is good fun for me aside from the settings of the ground contact points which have caused some troublish issues, namely... 1.Spontaneous and catastrophic explosions while in/near contact with the ground at over ~ 12 pitch: This seems due to the "tail tip" contact point invisibly extending outside the bounds of the airframe by a meter or two from the cargo ramp. At moderate pitch angles this "virtual tail" strikes the ground and triggers a sudden unplanned disassembly. Moving this contact point inward to the hinge of the ramp should prevent this from occuring and change the overpitching failuremode to a bladestrike. 2. Wierdish taxi behavior: CH-47Fs steer with their rear wheel(s) like a forklift. Swapping the <Features...> and <SteeringController...> between the front and rear wheels and setting inverserotation to true should fix that. I also noticed that the left and right front wheels are offset from each other? Kinda wierd.

Revision	2019-10-03 05:33 by Shuffl3
Additional Information	I see that the current config was sourced through one of these reports, it works well enough and that tweaking rotorlib.xmls can be annoying and time consuming. I'm kinda diggin it though. If there was some reference/low poly model I could use to align the points I wouldn't mind spending the time.

Revision	2019-10-03 06:25 by Shuffl3
Additional Information

Revision	2019-10-03 10:11 by Shuffl3
Description	The Huron rotorlib swap works and is good fun for me aside from the settings of the ground contact points which have caused some troublish issues, namely... 1.Spontaneous and catastrophic explosions while in/near contact with the ground at over ~ 12 pitch: This seems due to the "tail tip" contact point invisibly extending outside the bounds of the airframe by a meter or two from the cargo ramp. At moderate pitch angles this "virtual tail" strikes the ground and triggers a sudden unplanned disassembly. Moving this contact point inward to the hinge of the ramp should prevent this from occuring and change the overpitching failuremode to a bladestrike. 2. Wierdish taxi behavior: CH-47Fs steer with their rear wheel(s) like a forklift. Swapping the <Features...> and <SteeringController...> between the front and rear wheels and setting inverserotation to true should fix that. I also noticed that the left and right front wheels are offset from each other? Kinda wierd.

Revision	2019-10-03 05:33 by Shuffl3
Steps To Reproduce	Pilot CH-47 on the ground 1. Wheelbrake on 2. Engine on 3. Raise Collective to ~1/4 4. Gently pull back on the cyclic until the front wheels rise from the ground 5. goto 3rd person and observe from the side 6. Increase pitch by pulling farther back on the cyclic and applying additional collective as needed 7. Observe the rear suspension unload as it levers on an invisible point behind the model 8. Continue to Increase pitch 9. Spontaneously Explode.

Revision	2019-10-03 10:11 by Shuffl3
Steps To Reproduce	Pilot CH-47f on the ground 1. Wheelbrake on 2. Engine on 3. Raise Collective to ~1/4 4. Gently pull back on the cyclic until the front wheels rise from the ground 5. Go into 3rd person and observe from the side 6. Increase pitch by pulling farther back on the cyclic and applying additional collective as needed 7. Observe the rear suspension unload as it begins to lever on an invisible point behind the model 8. Continue to increase pitch 9. Spontaneously Explode.

Revision	2019-10-03 10:17 by Shuffl3
Description	Maneuvering on/near the ground can cause a catastrophic failure if the pitch angle exceeds ~ 12 degrees.

Revision	2019-10-03 10:17 by Shuffl3
Steps To Reproduce	Pilot CH-47f on the ground 1. Wheelbrake on 2. Engine on 3. Raise Collective to ~1/4 4. Gently pull back on the cyclic until the front wheels rise from the ground 5. Increase pitch by pulling farther back on the cyclic and applying additional collective as needed 6. Spontaneously Explode.

Revision	2019-10-03 10:17 by Shuffl3
Additional Information	I think one of the defined rotorlib contact points is sticking out the back of the model. If it hits the ground the system decides its time to go boom.