Southwest engine failure

[BusyLittleShop]

Originally Posted By: FowVay
The fan blade may have been ingested into the engine but upon initial liberation it most likely pulled forward and did the damage to the inlet cowling. The inlet (referred to as the nose cowl) cowling then came apart and caused the fuselage damage and ultimately broke the window.


I don't agree the light weight titanium blade upon liberation from its
power source possessed sufficient energy to inch its way forward
against the on rush of incoming air and hack repeatedly at inlet
cowl... I think the blade separated and collided with its neighbors
before ultimately ingested back into the engine just the way engineers
designed it and test video proves it...

Originally Posted By: FowVay

I feel that this is what damaged/weakened the nose cowl and vibrational forces and high speed air did the rest.


I agree... the real culprit was the non stop vibrational forces and
the resulting slip stream... true the engine shook its self to
destruction and debris damaged the aircraft fuselage, wing and
empennage, and the passenger interior compartment was penetrated but
its deceptive for the media to say the engine exploded...

 

[Shannow]

Originally Posted By: BusyLittleShop

I don't agree the light weight titanium blade upon liberation from its
power source possessed sufficient energy to inch its way forward
against the on rush of incoming air and hack repeatedly at inlet
cowl...


Unfortunately the laws of physics require not your agreement.

The fan is dragging massive amounts of air into the engine, the loads on it to the front are massive.

As soon as released from it's centripetal force, they immediately fly radially outward, and in the direction of their aerodynamic load (forward)...it's not "inching".

Your videos are different from the event...they have explosive charges to server the blade. High cycle fatigue means that the blade suffers none of the generalised effects of the explosion...it was attached one revolution, and unattached the next.

Look at the video I linked with Rolls Royce's explaination of their blade failure...that's what happens

(BTW, I've had multiple steam turbine blade failures to investigate...I've got some runs on the board in the area).

 

[FowVay]

Busy, don't underestimate the amount of energy that is taking place in a running jet. The fan blades are not as light as you might believe and when they're spinning around they hold massive amounts of force. I always questioned why the manufacturers would label a disk as being a critical rotating part but they place very little concern on the blades.

The investigation from the Southwest engine failure stated that: "two pieces of a broken fan blade were found inside the engine of the Southwest Airlines jet, but other pieces dislodged the cowling that damaged the wing and fuselage of the Boeing 737-700."

 

[cjcride]

Very interesting thread.
My first conclusion was the freed turbine blade did the cowl and window damage. I now feel it did get overcome by the tremendous inrush of air that was providing enough thrust to lift half the weight of the aircraft, plus overcome the resultant drag.

Appreciate all posts. Very good read.

 

[BusyLittleShop]

Originally Posted By: FowVay
Busy, don't underestimate the amount of energy that is taking place in a running jet.


I'll hold your thought Fow but after 20 years in the USAF one learns to never underestimate the degree of energy in high bypass turbo fans and turbo jets...

 

[BusyLittleShop]

Originally Posted By: cjcride
Very interesting thread.
My first conclusion was the freed turbine blade did the cowl and window damage. I now feel it did get overcome by the tremendous inrush of air that was providing enough thrust to lift half the weight of the aircraft, plus overcome the resultant drag.

Appreciate all posts. Very good read.


You're welcome... Inflight emergencies are interesting... I enjoyed each and everyone I investigated while serving as Quality Control Inspector USAF...