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Simulating engine fire

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Simulating engine fire

Postby Necolatis » Thu Jan 28, 2016 3:17 pm

I would like to simulate engine fire in a turbine-jet. So I have some questions on how that could work:

What can cause an engine fire?

Can overspeeding cause fire? For example for an aircraft built to do around mach 1.2 in the lower atmosphere, will going at higher speed after a dive, have a chance to cause fire?

The planes manual warns of using thrust reversing at very low speeds due to the hot exhaust can be sucked into the inlet, could this scenario cause fire?

What other scenarios could cause fire in engine?

How will engine fire affect the engine?

Will it typically decrease/stop the performance? If so, at once, or after a while, and how much?

If the fire can stop the engine, is there a chance to start the engine again?

How will controlling the engine affect the fire?

Can throttling down stop a fire? Or prevent it from getting worse?

Can cutoff help prevent the fire getting worse?

Can the lack of oxygen in higher altitudes help prevent/stop engine fire?

Is there other ways to handle an engine fire? Beside using fire extinguisher.



Thanks for any answers :)
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Re: Simulating engine fire

Postby Alant » Thu Jan 28, 2016 3:44 pm

This is probably not the best place to ask such a question. Better try google "aircraft engine fire causes" where you will be able to get much more informed results.

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Re: Simulating engine fire

Postby Johan G » Sat Feb 06, 2016 6:08 pm

As you most probably know (based on your question), flight/operations and service manuals rarely, if at all, mentions what can happen if for example engine limits are exceeded, only what the limits are.

To find out what really can happen there is few better things to do than a combination of:

  1. Searching for incidents and accidents related to a fault,
  2. trying to id the involved aircraft, date and location,
  3. looking for the final accident/incident reports, and finally
  4. skimming through the reports.

Usually there is a chain of faults leading up to an incident/accident, and the incident/accident report should probably be seen as the final statement about what happened. In addition the reports often have information on aircraft systems that might not be fully described in the flight or operations manuals.
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Re: Simulating engine fire

Postby eadsJose » Sat Feb 06, 2016 7:44 pm

Hello. I'm not really an expert about this topic but:

What can cause an engine fire?

The engine fire may be caused, in general, by only one problem: Abnormal airflow.
1. Bird collision: This can damage the blades of the engine, frequently the low and high pressure compression system.
2. Rollback: Excessive angle of attack can cause low airflow to the engine.
3. Volcanic ash: Ash can melt and adhere to the fan blades causing abnormal flow of air.
The engine works with an amount of air proportional to fuel. When the fuel flow is more than the airflow, the engine can catch fire.

Can overspeeding cause fire?
I don't know but i think that the overspeed may cause engine surge and the blades may break off. (Again abnormal airflow)

The planes manual warns of using thrust reversing at very low speeds due to the hot exhaust can be sucked into the inlet, could this scenario cause fire?
I don't know. The engine efficiency (on reverse) decreases below 70kt around. And low speed may cause engine stall. However in emergency landings some pilots use full reverse below 70kt.

What other scenarios could cause fire in engine?
Ice: Yes, Hail can damage the engine blades...
Fuel leak, engine generator overheat, etc.

How will engine fire affect the engine?
Excessive temperatures can damage other engine components (?).

Will it typically decrease/stop the performance? If so, at once, or after a while, and how much?
In case of fuel efficiency, of course. And time is according to the ETOPS rule.

If the fire can stop the engine, is there a chance to start the engine again?
I don't believe that the fire stops by itself once it has begun. If you have not applied the extinguisher, probably yes lol.

How will controlling the engine affect the fire?
In Airbus planes the steps are:
Thrust lever idle, engine master off, engine fire push button, agents: One and two if you are on ground. Only one if you are in the air... and two if the first doesn't extinguish the fire. And other steps (fuel x-feed, bleed, hydraulics, engine generator)

Can throttling down stop a fire? Or prevent it from getting worse?
I don't believe it. At idle the engine is still getting fuel.

Can cutoff help prevent the fire getting worse?
Yes, this is a step on the checklist.

Can the lack of oxygen in higher altitudes help prevent/stop engine fire?
I don't know.

Is there other ways to handle an engine fire? Beside using fire extinguisher.
Land ASAP.
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Re: Simulating engine fire

Postby Necolatis » Sun Feb 07, 2016 1:19 pm

Thank you :)
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Re: Simulating engine fire

Postby jaxsin » Fri Feb 26, 2016 12:34 pm

too add on to what jose said,
The engine fire may be caused, in general, by only one problem: Abnormal airflow.


This is essentially saying that any time you reduce the amount of oxygen in the air then you run the risk of flooding the engine with fuel that will not explode and instead catch fire and burn off because the combustion ratio is not within range. This again could makes sense to what jose said here
The planes manual warns of using thrust reversing at very low speeds due to the hot exhaust can be sucked into the inlet, could this scenario cause fire?


hot exhaust would contain a very low amount of oxygen and because you are already going slow, the engine is already limited by the amount of airflow it is getting(IE oxygen). If you snuff out the engine ignition and fuel still flows you run the risk of a fire as the fuel catches and consume what oxygen it can from the surrounding area.

Interesting topic, I did read one report where an engine would not start, so the mechanic said to change out some igniter. On next restart the engine caught fire simply because of an excess of fuel in the engine from the failed attempts to start prior to the fix.
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Re: Simulating engine fire

Postby jaxsin » Fri Feb 26, 2016 12:38 pm

Can the lack of oxygen in higher altitudes help prevent/stop engine fire?


A fire needs oxygen to burn, reduce the oxygen the fire will eventually snuff out. We know this because jet engines do not work in the vacuum of space.

The question here, can you climb high enough to see enough reduced oxygen to snuff out the fire and still maintain a climb with the other engine? I doubt it, the other engine still needs oxygen to work
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