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Old 3rd Dec 2017, 00:07   #61 (permalink)
 
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Sometimes pilots don't physically monitor the controls, especially on the ground, and insidious movement, pehaps caused by a sticky trim switch or malfunctioning parallel actuator, might catch the unwary.
Surely one of the most basic requirements covered in one's first flying lesson?
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Old 3rd Dec 2017, 10:02   #62 (permalink)
 
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Dauphne auto piot is a class example and led to fatalities . It inches the disk lower at the front and the disk you walked out of safely takes your head off when you return. ALWAYS approach and leave a dauphne from the side.
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Old 3rd Dec 2017, 13:25   #63 (permalink)
 
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Surely one of the most basic requirements covered in one's first flying lesson?
Agreed, but you'd be surprised how frequently we see pilots of all experience levels making this error - both on the ground and in the air. Perhaps the capability and reliability of modern autopilot systems, which can encourage pilots to operate routinely 'hands off', has a lot to do with this.
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Old 3rd Dec 2017, 21:55   #64 (permalink)
 
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Dauphne auto piot is a class example and led to fatalities . It inches the disk lower at the front and the disk you walked out of safely takes your head off when you return. ALWAYS approach and leave a dauphne from the side.
is that when you forget to blip the trim release after landing? The only reason it will beep the disc down at the front is because you didn't recenter the series actuators and re-datum the AP computer by pressing the trim release in after landing.
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Old 4th Dec 2017, 17:49   #65 (permalink)
 
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Im an engineer that had the misfortune to spanner Dauphanes The disk motoring forward was demonstrated to me after I walked into the disk from the front. The fatality was the Dubai Incident.
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Old 4th Dec 2017, 18:27   #66 (permalink)
 
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It doesn't just do it by itself - it has to be assisted by a pilot who doesn't know his AP system.

2 options - disengage the AP after you land or depress the trim release to recentre the actuators - then the disc won't move.
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Old 4th Dec 2017, 22:16   #67 (permalink)
 
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Well the incident in Dubai killed the operating Pilot. He got out rotors running to assist the passengers and walked into the blades on his return. I believe it was some time before he was found. Helicopter still running as if nothing was wrong.
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Old 4th Dec 2017, 22:51   #68 (permalink)
 
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Norways first AW101 on its side
How can this be the first? At least not yet anyway!
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Old 4th Dec 2017, 23:23   #69 (permalink)
 
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Well the incident in Dubai killed the operating Pilot. He got out rotors running to assist the passengers and walked into the blades on his return. I believe it was some time before he was found. Helicopter still running as if nothing was wrong.
Can you give more information on this? Which year and which company?
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Old 5th Dec 2017, 06:35   #70 (permalink)
 
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Well the incident in Dubai killed the operating Pilot. He got out rotors running to assist the passengers and walked into the blades on his return. I believe it was some time before he was found. Helicopter still running as if nothing was wrong.
And you want to blame the aircraft for that???????
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Old 5th Dec 2017, 12:25   #71 (permalink)
 
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The fatality was the Dubai Incident.
Wasn't there one on the Viking B in 1992 to a Bond 365N where the rotor struck and killed a member of the helideck crew?
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Old 5th Dec 2017, 17:06   #72 (permalink)
 
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And you want to blame the aircraft for that???????
I'm not familiar with the Dauphin but if you design a disc that motors forward to head chopping height after you land unless the pilot does something... guess what - at some point the oul Swiss cheese holes are going to line up.
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Old 5th Dec 2017, 19:55   #73 (permalink)
 
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Any AP with attitude hold functions can do this, its not unique to the Dauphin - if you don't redatum the AP by using the trim release or by beeping to a new datum or just disengaging the AP, the computer will go into an open loop condition and motor the disc to try and give you the attitude you last demanded of it.

Normally you would expect that it would try to regain the hover attitude if you haven't redatumed it and that would usually make the cyclic and the disc beep back/up at the front so if the AP was at fault in the Dubai incident then the pilot must have done something very odd with the AP.
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Old 5th Dec 2017, 21:23   #74 (permalink)
 
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Any AP with attitude hold functions can do this, its not unique to the Dauphin - if you don't redatum the AP by using the trim release or by beeping to a new datum or just disengaging the AP, the computer will go into an open loop condition and motor the disc to try and give you the attitude you last demanded of it.

Normally you would expect that it would try to regain the hover attitude if you haven't redatumed it and that would usually make the cyclic and the disc beep back/up at the front so if the AP was at fault in the Dubai incident then the pilot must have done something very odd with the AP.
The S-92 automatically disables attitude hold on the ground via WOW which seems to me to be a sensible design feature, although all the usual caveats regarding covering the controls and being aware of disc position obviously still apply.

Anyway, getting kind of off topic here... or maybe not, depending on what the Norgie report says
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Old 6th Dec 2017, 00:51   #75 (permalink)
 
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Normal practice used to be to disconnect the AP after landing. Controls should always be covered by one crew member while anyone is near or under the disc. Is this still procedure or has it changed?
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Old 6th Dec 2017, 18:25   #76 (permalink)
 
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Normal practice used to be to disconnect the AP after landing. Controls should always be covered by one crew member while anyone is near or under the disc. Is this still procedure or has it changed?
Not sure if that was directed at myself or not.

There is no need (and no SOP) to disconnect AP lower modes after landing on the 92. ATT mode deselects automatically.

The 225 I believe even has a disc centring button on the cyclic for ground use, which would imply to me that the parallel actuators of the AP are still in play.

Not aware of SOP for the AW101.
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Old 7th Dec 2017, 11:14   #77 (permalink)
 
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Not aware of SOP for the AW101.
No details on SOPs, but the AFCS disengages AP modes on ground. SAS and ATT remain engaged in a reduced capacity with the ATT datum reset automatically.
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Old 8th Dec 2017, 11:28   #78 (permalink)
 
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EH101s in the headlines?

Very unfortunate accident in Norway, but I had heard there was an incident or an accident involving a large heli in KSA a couple of week's ago? Anyone know if it was an EH101 too? Are they linked?
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Old 8th Dec 2017, 17:04   #79 (permalink)
 
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I had heard there was an incident or an accident involving a large heli in KSA a couple of week's ago? Anyone know if it was an EH101 too? Are they linked?
Reported - based on photographic evidence - to be an S-70A-1 Desert Hawk. See Saudi heli crash.

I/C
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Old 8th Dec 2017, 18:24   #80 (permalink)
 
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Normal practice used to be to disconnect the AP after landing. Controls should always be covered by one crew member while anyone is near or under the disc. Is this still procedure or has it changed?
Not with the later designs like the 225 and presumably the S92. The AP is engaged after start, remains engaged the entire time - ground taxiing, flight, landing on a moving deck etc - and only disengaged just before shutdown. It is automatically in a different mode on the ground which prevents any “disc motoring”. The advantage is that it’s one less thing to be able to forget (had a few 332s lift off offshore with AP disengaged, nearly crashed) and/or if you have to lift off in a hurry eg when taxying you have the AP straight away. It doesn’t use the WOW switches on the undercarriage (fortunately, as they are not the most reliable) but rather an algorithm that looks at several parameters and has various fallback modes should those parameters be unavailable. I imagine the 175 will be much the same.

Although the 101 is somewhat older tech, there’s a fair chance it’s similar.
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