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Alaska Airlines flight forced to make an emergency landing... 82

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One of these times, something serious could happen. [bomb]

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik
 
...cockpit voice recorders. There should be the requirement that they cannot be 'turned off'.

"It is an anomaly in the era of inexpensive and expansive digital storage, when the phone of each passenger onboard a flight could easily have more capacity than the plane’s voice recorder.

Now, Homendy wants the recording standard to change.

She is calling on the Federal Aviation Administration to require a 25-hour recording window for the cockpit voice recorder in all aircraft – a duration that is already a standard requirement under European airline regulations."



-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik
 
Dik said:
One of these times, something serious could happen.
I love your understated sarcasm, dik.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!
 
79826835-12949925-image-a-9_1704945048584_ypn9oj.jpg


Daily Mail.

It is plausible that the locking bolts were over-tightened and fractured the retaining track?
 
If that happened as long as the "vertical movement arrestor bolt(s)" would prevent the door from moving off the stops.

It would tend to bend the guide wall to decrease the width of the groove, rather noticeable, and the NTSB would have mentioned it. I expect the portion that was damaged bent the guide to increase the width of the groove.
 
The thing that gets me is that whilst weight is very important, for a door plug which is not used, why they don't have secondary or better locks between the two parts, plane and door.

So e.g a set of C shaped clips to go over say 4 of the stop pads which could then be fixed to the door using cables so they don't get lost if the door is removed at any point.

Those bolts look quite small and difficult to fit.

It's rare for me to praise the Dailly Mail, but that is a very good illustration and explanation of the issue

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
 
LittleInch said:
a set of C shaped clips to go over say 4 of the stop pads which could then be fixed to the door using cables so they don't get lost if the door is removed at any point.

The failure happened because the parts that are already defined as necessary didn't get installed correctly.

Adding more parts to install is not how to solve such failures.
 
If everyone does their job correctly when fitting and maintaining the plug, it has double or quadruple redundancy in the locking. I suspect that just a single bolt in any of the 4 holes would be sufficient to prevent opening in all but the most extreme circumstances, and two or more should make it impossible without hull damage to distort the frame. There shouldn't be that much force on the bolts in normal service.

I agree that it looks like it's difficult to fit the bolts. Every picture I have seen of them fitted has the nut and cotter pin on the cabin side, so the bolt has to be inserted by reaching around behind the fittings into the narrow gap between fitting and skin. It makes sense to have the nuts on the cabin side, as it would be an even bigger problem to insert and secure the cotter pin on the skin side, but the overall procedure looks a little difficult.
 
It's about making it much easier to see that they are not fixed in place or get lost. Plus those bolts seem rather small.

This door is not removed other than a major strip down so should be positively held jn place IMHO.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
 
I'm of the understanding that other models use the same door plug. If so, then failure to fit the bolts must be related to the work instructions related to the MAX 9.
Also, the way the bolts are fitted, it seems that neither the top nor the lower bolts can require to be torqued, as this would damage the fitting it passes through. The bolt is really just a pin, with castellated nut and cotter pin to keep it in place. Media reports of 'loose' bolts don't seem relevant.

Brad Waybright

The more you know, the more you know you don't know.
 
The loose bolts are on neighboring fittings and were discovered during the inspection of these doors on other aircraft. Loose bolts have previously been reported in the rudder control system. Loose fasteners are very much a concern, though not directly related to the departure of the door. None of the bolts found loose or missing should ever be loose or missing.
 
waross said:
No, The springs are compressed when the door is closed.
In normal closed position the springs are compressed and pushing upwards.

That's my take too, the plug door is being pushed upwards so it can be easily lifted by the operating staff. It makes me think that the plug door without and bolts could move upwards easily when the aircraft hits any bumps while on the ground and not pressurized but would it not easily move back down without being pushed.
 
The larger magnitude bumps are in the upward direction, tending to seat the door. In the downward direction is mainly free-fall which exerts no force. Vibration and elasticity of the airframe can allow shaking but there isn't much deflection in a typical fuselage, but that will be symmetric.
 
3DDave said:
The loose bolts are on neighboring fittings...
Thanks. That's a whole 'nother story. I thought it was in reference to the stop bolts that held the door in position to keep it from moving up. Now I've seen pictures of the closure hardware bolts hanging out. A much bigger issue, to be sure. Now I see why the FAA has kept the planes on the ground. Nobody is even sure what to check for yet.

Brad Waybright

The more you know, the more you know you don't know.
 
10000 loose bolts flying in close formation ;)
 
Weird, my post with a link to Boeing's job application page got removed.
 
On alot of commercial BB's links to jobs are removed due to free advertising which is worth quite a bit to the recruiting pimps.

 
Murph the A220 is 272 486 computers flying in formation apparently.

Even the toilet has one.
 
I can just see... cruising along at 37,000 and hit a slight 'bump'... that dislodges a door that is not properly secured... Why would terrorists strike an Alaskan airline?

It begs the bigger question... how much other stuff has Boeing put out that has been improperly assembled.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik
 
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