Flexjet Phenom down KSGR.

Having removed and installed the wing on numerous Lears it doesn't suprise me that an airplane with a similar method of attaching the wing would separate like that. I suppose it might even help to dissipate energy leaving the fuselage fairly intact and the occpuants relatively unharmed.
 
The wing is built as one solid piece then attached to the fuselage. Even the Citation X only has four attachment bolts!!!
 
The engines on the F-18 Hornet are attacked with 3 bolts. Not super relevant but it puts it in perspective. My guess is that the Phenom has the typical 4 attach points on the wing that bolt to the fuse.
 
I think what surprised me is in older planes you see one wing come off... I fly older designs that historically don't come apart like that. I wonder if it makes it safer or less so?


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MUCH safer! The separation of parts dissipates or absorbs energy that would otherwise be transferred to the cabin (occupants).

I was starting to wonder about this. Kind of like how seats would stroke down--letting the airframe absorb as many G's before hitting a human body with them. After I saw this was off the end (not the side of the runway) and it went through the water, I was thinking that was a hard deceleration. I wonder if, had the fuselage not separated, this could have looked like the Gulfstream after hitting that berm during the high speed abort up in the NE.

I'm amazed that nobody has commented on GPS or sat comms being a factor. :sarcasm: A bit of a drift, can somebody explain why the 300 has GPS inputs to the ADC? I watched a video of a test following a sat-based wifi installation. When they powered up the sat unit, the 300's GPS signal dropped like a rock to almost nothing. Not a good thing for a plane with that ADC link.
 
A bit of a drift, can somebody explain why the 300 has GPS inputs to the ADC?
No ADC link, an AHRS link. The AHRS uses the GPS as a correction signal. In very specific situations, a loss of GPS combined with certain attitudes can cause an AHRS miscompared, which kicks off the autopilot and causes a dual failure of the yaw damp and ventral rudder (just another YD), leading to severe Dutch roll at altitude.

I've flown through non-GPS areas (thanks government!) many times in the 300 and 100 without issues. It's a very specific situation but because of the results, it's understandably warned against.

See the slides below referencing the system logic, original incident, etc.:


PhJW7WE.jpg



spyKL8a.jpg



Hvq5s5c.jpg
 
No ADC link, an AHRS link. The AHRS uses the GPS as a correction signal. In very specific situations, a loss of GPS combined with certain attitudes can cause an AHRS miscompared, which kicks off the autopilot and causes a dual failure of the yaw damp and ventral rudder (just another YD), leading to severe Dutch roll at altitude.

I've flown through non-GPS areas (thanks government!) many times in the 300 and 100 without issues. It's a very specific situation but because of the results, it's understandably warned against.

See the slides below referencing the system logic, original incident, etc.:


PhJW7WE.jpg



spyKL8a.jpg



Hvq5s5c.jpg


ADC...AHRS...PFM Boxes...I knew it was one of those thingies. Thanks for clearing this up. Question #2: are there other aircraft that have GPS input to the AHRS that could result in similar consequences?
 
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