Santa Barbara Skycrane crash
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SkyCrane rear flight controls
"the rear seat is seldom, if ever used"
Does anyone have a picture or video of a SkyCrane rear flight controls installed or better yet, actually being used.
Thanks. Mike, fly911.
.
Does anyone have a picture or video of a SkyCrane rear flight controls installed or better yet, actually being used.
Thanks. Mike, fly911.
.
Join Date: Aug 2004
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S64 rear seat
The rear seat is used predominently for precision placement of loads and does a remarkable job (driven by very experienced pilots) considered the cyclic is very early fly by wire, the collective is mechanical
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At the risk of it appearing that I know somethihg about Skycranes, which I really do not.... It does appear to me that the photos of the poor machine lying upside down, show a tail rotor with very little damage. It certainly does not apear that it was turning when it hit the ground. Would stopping the main rotor as happened, also stop that tail rotor that quickly? Or could some other failure have caused it's stopping before the rollover was finished? Either way, it happened quickly!
S-64 Rear Seat Controls
Shawn has the control orthogonality correct. As to the question about "full authority": the rear cyclic acts thru the AFCS for pitch, roll and yaw. It has +/- 10 % authority, and that authority is shown on a cross pointer indicator. The 10 % control range can be shifted by utilizing the rear cyclic beeper trim, and the pilot can see where he is on the cross pointer indicator. "Back in the day" they'd make you fly around the pattern backwards from the rear seat before they'd sign you off.
Thanks,
John Dixson
Thanks,
John Dixson
Join Date: Sep 2005
Location: clinging to the wreckage
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another silly question
Glad no one was hurt
Does the rear facing seat have yaw pedals? cant really see in the clip above. if they are there it appears the pilot is sitting over them rather than having them in front
Does the rear facing seat have yaw pedals? cant really see in the clip above. if they are there it appears the pilot is sitting over them rather than having them in front
Join Date: Mar 2008
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The C150 in the circuit being overtaken by a 64 reversing around the pattern...
Rear Seat Directional Control
Tony 1969, as I wrote, the rear cyclic has yaw control integrated. One twists the control and voila-the big ship turns. Before someone raises the obvious: yes, the major challenge is to make clean, single axis inputs.
Thanks,
John Dixson
Thanks,
John Dixson
Join Date: Jul 2004
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John,
If I remember correctly the S64E did not have the yaw function on the back seat controls but the S64F did. I remember riding left seat while setting a radio antenna and the back seat pilot had to ask for yaw adjustments from the pilot flying the right seat. I could be remembering it incorrectly or it may have been something operator specific. I would swear there was some differences though between the E and F model cranes in regards to the back seat controls.
Max
If I remember correctly the S64E did not have the yaw function on the back seat controls but the S64F did. I remember riding left seat while setting a radio antenna and the back seat pilot had to ask for yaw adjustments from the pilot flying the right seat. I could be remembering it incorrectly or it may have been something operator specific. I would swear there was some differences though between the E and F model cranes in regards to the back seat controls.
Max
S-64 Rear Seat
Maxtorq,
CH-54A/S-64E had a modified S-61 type AFCS, Rear seat accomplished yaw control thru the twisting of the cyclic, but required manual beeping to extend the pitch/roll axis authority range. CH-54B/S-64F had the RH-53D type AFCS. Yaw control was still done thru twisting the cyclic, but the pitch/roll authority range extension was different. My memory is hazy on this part, but I think the range was extended thru a trim reshift if you either got to some threshold of the existing authority or touched the electronic cyclic stops. Think it was the former. Maybe some old Crane pilot can help here. In any case, yaw was available on both, and thru twisting the cyclic. People will notice that on the newer SA fly-by-wire controls now in flight test, the yaw controls utilize electric pedals, making pure single axis yaw inputs a lot easier.
Thanks,
John Dixson
CH-54A/S-64E had a modified S-61 type AFCS, Rear seat accomplished yaw control thru the twisting of the cyclic, but required manual beeping to extend the pitch/roll axis authority range. CH-54B/S-64F had the RH-53D type AFCS. Yaw control was still done thru twisting the cyclic, but the pitch/roll authority range extension was different. My memory is hazy on this part, but I think the range was extended thru a trim reshift if you either got to some threshold of the existing authority or touched the electronic cyclic stops. Think it was the former. Maybe some old Crane pilot can help here. In any case, yaw was available on both, and thru twisting the cyclic. People will notice that on the newer SA fly-by-wire controls now in flight test, the yaw controls utilize electric pedals, making pure single axis yaw inputs a lot easier.
Thanks,
John Dixson
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Erickson S64 machines do not have the yaw capability on the cyclic. Yaw control is accomplished by communication with the front seat pilot on the pedals.