UA flight 328 OMG....

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pucho812

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third stone from the sun
well that was an interesting thing to roll across the t.v. while working in the shop today.  As usual planes are designed to fly on one engine and pilots train for emergencies as best as possible but even still there is an X factor.
Luckily everyone survived and no known injuries except damaged property...

(the engine)
https://www.youtube.com/watch?v=YFSbSHake-w


https://www.youtube.com/watch?v=o1CFMAJUMEI


Listening to the ATC(air traffic control) live
https://forums.liveatc.net/index.php?action=dlattach;topic=16129.0;attach=10823
 
Holy shit!  Can't imagine looking out the passenger window and seeing that!  Nor having part of the engine come down in your back garden.

Well done the pilot and co etc. for averting tragedy
 
Winston O'Boogie said:
Totally.  Not only would I have shat my underwear, I'd've shat the dude's next to me too!

I concur. I also would have as well. I don’t like to fly, but I do out of necessity when required. I have been on some bad flights. But I still go knowing how safe it is. Even in such an emergency they made it back safely.  Job well done by all involved.
 
That was a pratt and whitney engine and suffered cracked compressor/turbine blades. (My older brother worked at P&W back in the 60s-70s).

Yes the aircraft can fly on one engine, but the safe landing weight is well less than typical take off weight if fully loaded with fuel for a long flight. They may have dumped some fuel before landing, or just chanced landing heavy to avoid spending more time in the air with a compromised airframe.

===

A similar accident a couple years ago sucked some unlucky woman out through a window when a turbine blade let loose and broke a cabin window in flight.

JR 
 
JohnRoberts said:
That was a pratt and whitney engine and suffered cracked compressor/turbine blades. (My older brother worked at P&W back in the 60s-70s).

Yes the aircraft can fly on one engine, but the safe landing weight is well less than typical take off weight if fully loaded with fuel for a long flight. They may have dumped some fuel before landing, or just chanced landing heavy to avoid spending more time in the air with a compromised airframe.

===

A similar accident a couple years ago sucked some unlucky woman out through a window when a turbine blade let loose and broke a cabin window in flight.

JR

Interesting information. When I first posted they didn't share any info as to why the engine went tits up.

I remember the incident of a women getting sucked through the window. I am not sure if we are thinking of the same one, but I am thinking of a southwest airlines flight and she was only partially sucked through the window. She was brought back into the plane and iirc her death was from sustained injuries.  You may remember a flight to Hawaii in the 1980's or 1990's where part of the  fuselage came off, basically creating a convertible for a section of the plane.  Another  air disaster that could have easily ended way worse than it did.

 
pucho812 said:
Interesting information. When I first posted they didn't share any info as to why the engine went tits up.

I remember the incident of a women getting sucked through the window. I am not sure if we are thinking of the same one, but I am thinking of a southwest airlines flight and she was only partially sucked through the window. She was brought back into the plane and iirc her death was from sustained injuries.  You may remember a flight to Hawaii in the 1980's or 1990's where part of the  fuselage came off, basically creating a convertible for a section of the plane.  Another  air disaster that could have easily ended way worse than it did.
Yup, today on the news I saw a picture of the broken turbine blade (stub). Yes the unfortunate window incident was Southwest.

IIRC, the airplane fuselage that failed in flight was due to corrosion and fatigue, not damage from an engine grenadeing. Aircraft design is always a tradeoff between weight and strength.
===
I asked my brother about how they test the engines for cracks, and they spray them with a fluorescent dye that soaks into the small cracks, then becomes visible under black light.

JR
 
I had to search for the manufacturer of the plane. None of the news reports mentioned it. It was a Boeing.

The same day, another Boeing lost parts of it's engine when taking off from Maastricht airport. No casualties, only damage to cars and houses in the flight path.
 
cyrano said:
I had to search for the manufacturer of the plane. None of the news reports mentioned it. It was a Boeing.

The same day, another Boeing lost parts of it's engine when taking off from Maastricht airport. No casualties, only damage to cars and houses in the flight path.
That second Boeing incident was a  different airframe (747 cargo transport) but similar (smaller) Pratt and Whitney PW4000 engine.

JR
 
JohnRoberts said:
Yup, today on the news I saw a picture of the broken turbine blade (stub). Yes the unfortunate window incident was Southwest.

IIRC, the airplane fuselage that failed in flight was due to corrosion and fatigue, not damage from an engine grenadeing. Aircraft design is always a tradeoff between weight and strength.
===
I asked my brother about how they test the engines for cracks, and they spray them with a fluorescent dye that soaks into the small cracks, then becomes visible under black light.

JR

So basically they are testing them like tires, the soap and water method but a dye instead.
 
pucho812 said:
So basically they are testing them like tires, the soap and water method but a dye instead.
My brother says they do xray or ultrasonic testing outside of the plane but still mounted in the air frame the dye and UV light method is more practical.

===

Newspaper articles are now second-guessing the robustness of the cowling to capture all the flying parts, but some of the broken blades can actually fly out the front opening so impossible to completely contain all possible exit vectors. Not to mention additional weight of a heavier cowling.

JR
 
unfortunately in a capitalistic society aeronautical engineering is driven by economics rather than safety.

more more more.  we want more people on board. we want more miles per gallon, the people living near the airport want less noise.

so you have bigger aircraft to squeeze more people on board, which means more fuel, which means more weight, which means gigantic engines, which means more noise, which means increased bypass ratio for less noise and better fuel economy, which means bigger blades, which means more stress, all this compounded by the trend toward fewer motors (2), even for overseas flights,

there is a bell shaped curve in my opinion of the optimal aircraft size, and that would be, oh, say, a 727 or somewhere around there.

maybe bigger. i notice that southwest has very few aircraft failure than other carriers, and that they load those planes quick, and that they are in and out of the airport easier, what model do they use? 737 right?  not the max, well they just bought a bunch, so yes the max, so i think that is probably the best plane, they do short hauls mostly, which is what aircraft should be limited to in order to be more safe by limiting fuel, passengers and thus weight which means less stress. why does everybody need to fly allover the earth? can they not do a skype meeting or send an email? save the planet. save lives. have you ever seen a world map of all the airplanes in the air? it is crazy!

Every day, FAA's Air Traffic Organization (ATO) provides service to more than 45,000 flights and 2.9 million airline passengers across more than 29 million square miles of airspace. 16 million flights a year! if you tempt fate by asking that many people to defy gravity, then of course you will have incidents.

losing one motor? no big. they test those things on the bench for the exact failure that happened in coloroado. they place small charges under the blade and watch the action when the fuse is lit,
there is some randomness to the path of the projectiles which contain tremendous amounts of kinetic energy  due to the speed at which they rotate, MV^2, so speed gets squared,

that P and W  4000 was designed for about 64 K thrust, using a 100 inch an. but accountants wanted more people on board each plane so it shot up to 98 K thrust with a 112" fan, seems like when they modify an engine for more thrust, there is a safe limit as to what you can squeeze out of the original compressor structure.in this case, the colorado plane was in it's climb, which is the hardest part of the flight for a motor. in fact, the heat build up is so bad that by the time that plane reaches cruising altitude, the motor is just below melting point. this drove the JT9D engineers nuts, they could not seem to gat a 747 up to 30 grand without something snapping. in fact, the chief engineer wanted to have a JT9D put on his front lawn so he could go out there every night and shoot it with a shot gun!  the 4000 is patterned after the JT9D.

those fan blades are about 6 feet long, that means the tip of the blade is traveling a 38 foot circle, 2000 times a minute, which is 836 miles per hour, lets say that carbon fiber blade weighs 40 pounds, that means the blade has about 1 million foot pounds of Kinetic Energy, but divide that by 2 or more to get the average since not all parts of the blade move that fast, so that Nacelle has to contain about 500,000 foot pounds if just one blade snaps. otherwise the blade will cut through the fuselage like a knife thru soft butter. luckily the wing is located out away from the flight path of the blade and this is no accident.

since this plane was at about 10,000 feet, and things were starting to get warm due to a healthy passenger load, and since the tower told the guy to alter his course a bit, which meant revving up those stressed out motors a bit more, and since KE has velocity squared, you can see that the KE of the fan blade increased exponentially as it left it's moorings, much to the chagrin of the passengers sitting on the let side of the plane.

but losing an engine is no big deal, hell, some pilots land those aerodynamic bricks with zero engines. well, not all the time, but sometimes, with varied results.
 
so  Pratt and Whitney is the new whipping boy.

despite the teething problems early on, (anyone remember the new 747's with concrete blocks hanging on the engine-less wings), the JT9 proved to be very reliable.
shall we recall National Airlines flight 27 with the exploding GE CF6, sucking a passenger out the broken window?
how about United flight 232 that cartwheeled in Souix City, after losing all hydraulics due to the GE CF6 grenading?
who can forget, just a few years ago, our darling Southwest and the disintegrating CFM56 and the unlucky female passenger.

the lawsuits that followed UA 232 resulted in United not ordering any GE engines for years.
their 747-400's and 777-200's including the one involved at Denver were fitted with Pratts.

the new geared Pratts on Airbus A220's are now proven and with the latest tech.
 
My older brother worked for both P&W (hartford) and GE (schenectady) decades ago.

Until recently he was consulting to the power generation industry dealing with land based turbines. 

JR

[edit- for today's TMI my avatar picture was taken with me standing in front of a bank of manometer (pressure/vacuum) tubes. The polaroid was the easy way to log all the measurements. I was an out of work college dropout with nothing better to do in the middle of the night, and my brother was working on his PHD doctoral thesis research. He was researching droplet formation inside a supersonic nozzle with super saturated steam... a real mouthful. He sprayed steam through the nozzle and then shot a red laser through the spray to capture shadows/images. This was high tech for 50+ years ago. The apparatus was so loud he had to run his experiments when the building was empty. I was just free labor. [/edit] 
 

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