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Old 01-28-2020, 08:18 AM   #11  
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Nevermind. Had footage but don’t think it was the kobe crash
While the terrain does resemble SOCAL, that crash video does not match eyewitness reports or the weather conditions known to exist at the time of the crash.

Also different paint job.
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Old 01-28-2020, 10:46 AM   #12  
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While the terrain does resemble SOCAL, that crash video does not match eyewitness reports or the weather conditions known to exist at the time of the crash.

Also different paint job.
Blue and white, right? If you saw the other gray-black picture, I think that was promotional plastic wrap.
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Old 01-28-2020, 12:07 PM   #13  
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Blue and white, right? If you saw the other gray-black picture, I think that was promotional plastic wrap.
The wreckage is blue and white. There are two pictures of the airframe floating around, one is a "carbon" style paint job, the other is the obviously more recent blue and white.
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Old 01-28-2020, 07:25 PM   #14  
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Yes we can decipher every detail, though the cause is nothing new.

The work ‘Uncle’ comes to mind.
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Old 01-28-2020, 08:55 PM   #15  
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So what happens now? The aircraft didn’t have a black box? Does this mean this will be a mystery?


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Old 01-28-2020, 08:56 PM   #16  
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I wouldn't consider instantaneous mode C data to be accurate, absent other info. It's not a designed to be an FDR.


Oh. Nvm then!


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Old 01-29-2020, 07:12 AM   #17  
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I wouldn't consider instantaneous mode C data to be accurate, absent other info. It's not a designed to be an FDR.
If it's derived from ADS-B Out, it's usually highly accurate w/1 second update.
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Old 01-29-2020, 07:54 AM   #18  
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My helo knowledge is very limited, but I do know that a ‘retreating blade stall’ can occur after an abrupt pull up, especially when operating at high gross weight and high speed. The result of such, is loss of lift and a rolling motion to the left.

Could the pilot have suddenly realized his terrain situation, and initiated an abrupt pull up, and inadvertently stalled? This could account for the left turn and sudden altitude loss.

Another thought. Has this model of helicopter ever had an instance of the rotor disc contacting the tail boom, after an abrupt pull up?
1. Retreating Blade Stall: Not likely the culprit here. If anything the abrupt cyclic input would result in a transient droop in rotor RPM, which could be exacerbated in high/hot/heavy conditions (not the case here). Rotor blade stall is typically something you'd expect to encounter in a high speed, power-on dive, not while performing an aggressive climb to clear a cloud layer. Thinking about this phenomena as you would a typical fixed wing airplane stalling isn't going to do you any good. Simply increasing AOA in helicopter (read: nose attitude in relation to the horizon), no matter how abruptly, is not going to result in a stalled condition. If the climb is continued and conditions are right (i.e. high/hot/heavy situation) power required will eventually exceed power available and the aircraft will begin to settle.

2. Rotor disc contacting the tail boom: The fully articulated rotor head found on the S-76 is more efficient and survivable than something you might find on aircraft with an underslung rotor system (see AH-1W, UH-1N, Bell 206, etc). In negative G situations, the possibility exists for underslung systems to "flap" resulting in something called mast-bumping or even the main rotor blades impacting the airframe. With the fully-articulated head, this is not something that would really ever be a concern. If you wanted to, you could unload the head significantly with little to no impact on aircraft performance.

Many things could have happened here, but looking at the weather, the flight path, and hearing the ATC communications in the minutes before the crash, it's easy to look towards spatial disorientation as a likely culprit. Reference the crash of the Army H-60 carrying the MARSOC team off Panama City a couple years back, and you'll see similar things (even with 2 pilots). A strong cyclic pop into the clouds resulting in what would have to be an immediate transition to an aggressive IFR scan is a recipe for disaster, especially in a single piloted aircraft. Having felt the effects of severe spatial-d many times in many types of helicopters, I can attest to the fact that it is not something easily recognizable. Couple that with close proximity to mountainous terrain and the results can, and have been, disastrous.

Last edited by TheRotorTrash; 01-29-2020 at 08:10 AM.
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Old 01-29-2020, 10:41 AM   #19  
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..... A strong cyclic pop into the clouds resulting in what would have to be an immediate transition to an aggressive IFR scan is a recipe for disaster, especially in a single piloted aircraft....
This is just a horrible tragedy, and aside from a catastrophic mechanical failure, I was trying to find a sequence of events that an experienced pilot could allow to happen that would have resulted in this accident. Completely conjecture of course, but after reading the insight from RotorTrash and viewing this recreation of the flight path in VFR conditions (skip to the last 2 minutes),

Accident path flown VFR

I'm left wondering if the answer isn't just as simple as that.

I know fixed wing commercial aviation life, and that you are trained to get out of inadvertent IMC; but how hard is it for an experienced single pilot helo to do a 180' turn in IMC? If this guy flew in the LA basin he must of had plenty of actual time, how could this do him in?
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Old 01-29-2020, 11:15 AM   #20  
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I know fixed wing commercial aviation life, and that you are trained to get out of inadvertent IMC; but how hard is it for an experienced single pilot helo to do a 180' turn in IMC? If this guy flew in the LA basin he must of had plenty of actual time, how could this do him in?[/QUOTE]

I'm by no means insinuating that any of this or what I wrote previously happened here, just to get that out there, but the transition from IMC to VMC low to the ground can get you pretty quick in a helicopter. Even an experienced IFR pilot can find himself/herself in a situation where they think they're wings level when, in fact, they're 60 degrees left wing down. Most here are well-versed in the various illusions that you can experience without adequate visual cueing, but from my experience it is even more pronounced in a helicopter (I'm now a 121 guy except for one weekend each month, if that counts for anything). A climbing, decelerating turn in the goo can do some pretty gnarly things to your sensory abilities. I've seen guys (me included) keep on rolling through a turn all the way towards 90 degrees still thinking that they've rolled out on course, as well as those (myself) flying along "straight and level" before the rotor RPM horn is screaming at them as they begin to effectively slide backwards out of the sky. It's amazing what the inner can convince the body of. That video was interesting, but the lack of ceilings and fog present makes it seem like much more of a benign situation than it most-likely was in real life. As you get forced lower and lower, things can start to degrade on all levels to include your instrument scan.

This is without a doubt a horrible and tragic event. Hopefully they can gather some information that sheds some light on the cause. At this point, anything is possible, but those conditions (based on my location in SoCal and weather reports to this point) were not something that I'd be comfortable flying in, especially in a single piloted aircraft with passengers on board.
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