Penstar helo down. South Philadelphia suburb.

Great job of performing a successful autorotation. One skid was torn off, the other flattened to the bottom of the fuselage, indicating the helicopter hit the ground in an upright and level position.

Just minor injuries for three crew and infant medical.passenger.
 
luvflyin said:
What could account for one to go into a roll like that?
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There are various aerodynamic conditions (retreating blade stall) or control issues (loss of stability systems) that can initiate uncommanded pitch/rolls. This particular model is inherently unstable so if it loses part of its SAS input it can make for an interesting flight. And this model has a past on this issue especially when set up for SPIFR.
 
luvflyin said:
SAS, SPIFR ???
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My bad. SAS: stability augmentation system. Some helicopters need a system to smooth out flight control inputs. SPIFR: aircraft is certified for single pilot IFR ops. It all boils down to there are electrical servos between the cyclic stick and the blades which if they go awry can make the most experienced helicopter pilot look like its their first flight in a helicopter.
 
Bell206 said:
My bad. SAS: stability augmentation system. Some helicopters need a system to smooth out flight control inputs. SPIFR: aircraft is certified for single pilot IFR ops. It all boils down to there are electrical servos between the cyclic stick and the blades which if they go awry can make the most experienced helicopter pilot look like its their first flight in a helicopter.
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Thx
 
Bell206 said:
There are various aerodynamic conditions (retreating blade stall) or control issues (loss of stability systems) that can initiate uncommanded pitch/rolls. This particular model is inherently unstable so if it loses part of its SAS input it can make for an interesting flight. And this model has a past on this issue especially when set up for SPIFR.
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Yep, friend flys them and he said they only fail that stuff in the sim and it’s extremely difficult to get it under control. SAS / AP failure in the 407 you’d be inverted in about a second or two if you don’t have your hand on the cyclic.

Since there was a noise just prior I was thinking cyclic hard over maybe. Had that one in my last 407 sim event. We had never done that one before in the old sim so I didn’t know what was happening. I had gone through 180 degrees off roll before I reached up and turned off the hyd switch. IP was behind me laughing that I did a complete roll and never got a “red screen.” ;)
 
Barrel rolling a helicopter seems...bad
 
Velocity173 said:
Since there was a noise just prior I was thinking cyclic hard over maybe.
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There were 2 similar events a number of years ago that had the same clunk noise from above then got unstable. They believed the SAS decouple system was activated either by accidental hit on cyclic or an internal fault. When you decouple the SAS the electric side of the electro-hydraulic actuators goes immediately to nominal which can induce a sudden change to the blade pitch. This sudden pitch change could possibly have been the clunk noise. And if this happens when your AP coupled and "busy" with other tasks you're a little behind the events as in the other cases they thought it was a dual engine failure at first.
 
Hengelo said:
Barrel rolling a helicopter seems...bad
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Not unless you're having fun at the time. There are some better quality Red Bull vids out there using the BO-105 but the one below is by the master. A little factoid, the model in this accident was originally called the BO-108 and was to replace the 105 and has a few of those original features.
 
Great Googly Moogly! I almost code-browned myself just watching that.
 
Velocity173 said:
Yep, friend flys them and he said they only fail that stuff in the sim and it’s extremely difficult to get it under control. SAS / AP failure in the 407 you’d be inverted in about a second or two if you don’t have your hand on the cyclic.

Since there was a noise just prior I was thinking cyclic hard over maybe. Had that one in my last 407 sim event. We had never done that one before in the old sim so I didn’t know what was happening. I had gone through 180 degrees off roll before I reached up and turned off the hyd switch. IP was behind me laughing that I did a complete roll and never got a “red screen.” ;)
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In the EC135 sim they do in fact fail the SAS but I have also had an IP fail the SAS on me in the aircraft while under the hood. It makes for a wild ride but it certainly gets you to know the muscle memory for the recovery.

The 407 I fly on the side doesn't have SAS so I have nothing to compare it to.
 
Bell206 said:
There were 2 similar events a number of years ago that had the same clunk noise from above then got unstable. They believed the SAS decouple system was activated either by accidental hit on cyclic or an internal fault. When you decouple the SAS the electric side of the electro-hydraulic actuators goes immediately to nominal which can induce a sudden change to the blade pitch. This sudden pitch change could possibly have been the clunk noise. And if this happens when your AP coupled and "busy" with other tasks you're a little behind the events as in the other cases they thought it was a dual engine failure at first.
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It looks like my characterization of the event that brought the helicopter down as a powertrain failure and autorotation to landing was incorrect, just as you asserted in PMs between us.

Those PMs, along with the information you posted above, give a rational explanation for the chain of events that occurred. Thanks for providing the clues and details that I missed.
 
Bell206 said:
Not unless you're having fun at the time. There are some better quality Red Bull vids out there using the BO-105 but the one below is by the master. A little factoid, the model in this accident was originally called the BO-108 and was to replace the 105 and has a few of those original features.
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The same/similar routine as this? (I'm guessing the same pilot, too)
 
asicer said:
The same/similar routine as this? (I'm guessing the same pilot, too)
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That was one of the Red Bull helicopters with Chuck Aaron flying it. I believe they scripted the movie routine around Aaron's Red Bull routine. The pilot in the video I posted is Charly Zimmerman who is in his 80s and no longer flies.
 
k9medic said:
In the EC135 sim they do in fact fail the SAS but I have also had an IP fail the SAS on me in the aircraft while under the hood. It makes for a wild ride but it certainly gets you to know the muscle memory for the recovery.

The 407 I fly on the side doesn't have SAS so I have nothing to compare it to.
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You think it’s possible a SAS / AP fail could cause an accident like this?
 
Just gotta keep positive G on it…done it many times. :D

 
A random comment.

Every time I notice the thread title, I read "Pornstar helo down". Then I re-read the title and am disappointed.
 
Velocity173 said:
You think it’s possible a SAS / AP fail could cause an accident like this?
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Unlikely to produce a roll. Think oh58 with no cyclic friction or force trim.

Not crazy but certainly a wet noodle.

I personally know a pilot who lost an autopilot and has a sas failure in IMC and was able to fly it safely to the ground.


Sent from my iPhone using Tapatalk
 
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