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Boeing again 47

Circling back to the thrust links (an no, I'm not trying to kick Boeing when they are down):

waross said:
And these motor mounts were different from all of the motor mounts that Boeing successfully designed in the past how?

The 777X thrust links are made from Titanium, although I'm not sure which alloy.

Most thrust links I have knowledge of, including those of the 777-200 and 777-300 are made from 15-5PH, so they switched materials.

I'm very curious why they did this, if anyone has insight, other than "minimal weight savings".

Alistair_Heaton said:
It's quite a common occurrence. The q400 had it's engines derated 3-4 times due to cracking of multiple structural bits.

I never did a Max TakeOff Power in one in 2700 hours, even with the final derated certified version.

OK, but I don't really see this as a quasi-static or limit loads issue. They found a completely severed link which caused them to inspect the rest of the test fleet, and they found several more examples of cracking. This seems like a potential fatigue issue to me.

Reminds me of the issues Airbus had with dwell fatigue on some of the GE engines it was using. Alpha titanium and even alloys like Ti-6Al-4V are not immune to dwell fatigue especially in environments with long periods of mean stress hold in the VA spectrum (kinda like a thrust link...). Those GE components were seeing lives orders or magnitude below predicted.

Again, makes me curious why they would choose to switch from steel to titanium.

If I could hazard a guess based purely on speculation, it seems like they either had a fundamental misunderstanding of their fatigue environment, or there is a major issue with the materials / processing / manufacturing, or both. I have to assume the thrust links would have been extensively fatigue tested before this phase of development.

Something is definitely not passing the smell test here. I don't think we can chalk it up to "damage like this happens all the time, they'll just end up derating the engine".





Keep em' Flying
//Fight Corrosion!
 
There is counterfeit Titanium sloshing around the industry. Might be in these parts. You can guess the source.
 
Follow the link and scroll down a little. After the third paragraph is an audio clip of the conversation and the sound.
Thanks, Opps409.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!
 
At first I thought it was aliens but turns out it was a misconfigured audio setting. Press "Settings" scroll down to "Audio" ...
 
I wonder how many MBA Management Layers this task had to flow down thru, to reach the Junior Engineer, who provided the Lego Style Tutorial for manegement to run back up the chain of command?
 
There's reports that Boeing is pissed at NASA since they were NOT in the meeting where it was decided that the two stranded astronauts would be returning to earth as passengers on a SpaceX mission.

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:

The secret of life is not finding someone to live with
It's finding someone you can't live without
 
Doubling down and putting corporate pride ahead of safety. Brilliant strategy.
 
I wonder if that sound is a junior engineer who went AWOL just before the launch when he was accidentally closed into a void space.
His ghost is still trying to get out.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!
 
Rolls Royce XWB-97 engine seems to have a fuel nozzle.issue according to Cathay Pacific.

There has been nothing issued by RR or the certification authority for it EASA.
 
My understanding, at least this is what I was told when I worked for McDonnell Douglas, was the commercial jetliners are sold without engines. That's a separate contract between the airlines and the engine manufacturer. When the planes are ordered they just specify what engine is going to be used and when they're ready to install the engines, they show-up with a team from the engine manufacturer who are ultimately responsible for installing and testing the engines.

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:

The secret of life is not finding someone to live with
It's finding someone you can't live without
 
They are sold without engines, but they are certified to use only certain engines. Airbus would have certified those engines for their aircraft. They do this, at the least, because the mount and the enclosure are designed by the aircraft maker and all the other systems on the aircraft that interface with the engine, including pilot training.
 
Yes the A380 had different engines for different customers. Some had Rolls Royce (including flight QF32 where an engine exploded), and some had Engine Alliance
 
Starliner landed OK. Seemed like everything worked properly.

Edit: Apparently 1 capsule thruster didn't work correctly, but it's on the capsule so it can be diagnosed.
 
Good news

And I am quite glad they didn't risk the crew.
 
It’s a question of whether it is one of the 30 companies that make up one of America’s most closely watched stock indexes, one taken as a proxy for the health of the overall economy by many people.

That disingenuous CNN pr*ck. The decline in price is compared against an artificial bump up in stock price and weathering a pandemic.

As to being a proxy for the health of the overall economy? It's a very good example of how corporate America operates. That's the problem for those at the stock market working to gouge out as much cash from stupid investors as possible. If investors can see how corporate America is actually working at Boeing they will understand that all of them are doing the same crooked crap.

boeing_wxfano.png
 

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