Engine Damage

Disclaimer: 

▪︎This content is Not an official document and does not represent the views of Airbus or any other aviation authority.

▪︎The information provided may be incorrect or misinterpreted and should not be relied upon for decision-making. 

▪︎Always refer to official documents and consult with a qualified aviation professional before making any decisions based on the information provided in this blog post.

▪︎The information provided in this blog post is based on personal study and review.

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Engine Fail Ecam

In the event of engine failure, the crew must determine whether the engine is damaged or not. Depending on this determination, the course of action for the engine varies, such as discharging the fire bottle or not.

 

In airline experiences, I've heard some instances where the crew discharged the fire bottle assuming the engine was damaged when they actually had an enfine failure situation.  

However, after inspection, they have found out  that the engine was actually undamaged.

While neither the airline company nor the manufacturer did not blame the crew's action,

 

 

Typically, companies express gratitude and recognize the crew for successfully handling the engine failure procedure and managing the abnormal situation.
However, even as the company acknowledges the crew's actions,

they also highlighted the fact that the engine was not damaged, perhaps to encourage crews to be more cautious when determining engine status.

It feels like there seemed to be some regret regarding the unnecessary cost incurred for engine repair. though they can not acutally say it. 

It's challenging for the company or even the manufacturer to provide a clear method for distinguishing engine damage due to the multitude of possible situations. There's no definitive formula or procedure, and even computers may struggle to accurately determine engine condition in the event of failure. 

This is why the ECAM (Electronic Centralized Aircraft Monitor) prompts the crew to assess whether the engine is damaged or not.

 

 

What the Manual says.. 

 

In airbus fcom and FCTM. it says crew can SUSPECT the engine damage if the flight crew observes TWO or MORE of the following symptoms. 

 

1. rapid increase of EGT above red line

2. important mismatch of the rotor speeds or absence of rotation

3. Significant increase of aircraft vibrations and/or Buffeting.

4. Hydraulic system loss

5. Repeated or uncontrollable engine stalls. 

 

So the manual says they need two or more of the these symptoms. in FCOM, it even says on layer 2. which is "nice to know" information. 

FCOM engine fail "nice to know" information

 

I recall there used to be a mention of "loud noise" as one of the symptoms to identify engine damage in the past, but it seems they have since removed it. I attempted to find further explanations or descriptions about engine damage, but those were all I could locate.

During simulator exercises, instructors can insert engine failure or engine failure with damage. 

However, even when instructors inserts an engine damage scenario to trainees in the simulators,

 

I think it's challenging to determine whether the engine is damaged or not in the simulator for the trainee.

If we were to apply the "two or more of the following symptoms" rule, I believe it should be considered that the engine is not damaged unless the instructor introduces severe vibrations or other such symptoms separately and adds them together.

 

 

 

 

 

In the Simulator. 

In my personal experiences in the simulator, engine failure scenarios were categorized by either a decrease in N1 or N2 with or without a loud bang sound, followed by whether N1 or N2 remained operational afterward.

I used to determine whether the engine was damaged or not simply by observing the rotation of N1 or N2, considering the presence of a loud bang. 

The simulator instructor could have chosen to include two of the following symptoms if they wished to do so.
However, it was hardly the case that two of the following symptoms accompanied together. 

 

 

Following this rule of two or more symptoms, I believe that in most cases in the simulator where the instructor simply selected engine failure or engine failure with damage in the simulator's computer system, the outcome would likely be engine failure without damage, unless the instructor separately added other symptoms.

(I do not have the experiences of running the simulator. but only as in my experiences, i guess so..) 

 

 

of course in real life. things will be more complicated, 

but these were that symptoms that we can tell about the engine damage according to the manaul.