Fire warning light

[denver]

So there you are doing engine runs for the un-metered fuel flow adjustment in a Cessna 421 and the right fire warning light comes on. You shut down and go to inspect and find that the temp sensor probe ground wire came disconnected. The problem gets fixed and 2 months later on a flight with the CEO and board of directors of Rothbard Steel on board you launch into low IMC. 200 feet up the fire warning light comes on on the right engine but there is no smoke or any evidence of fire from visual inspection. Do you:

1. Immediately shut it down, blow the bottle and approach back into the airport at 200 and 1/2.

2. Keep the engine running due to the previous incident and no secondary indication, no smoke or anything. After all, it's at minimums and the weather where you are going 100 miles away is clear.

3. Shut it down, blow the bottle and continue on to your destination even though the wing spar could have been weakened if there were a fire.

 

[MikeD]

So there you are doing engine runs for the un-metered fuel flow adjustment in a Cessna 421 and the right fire warning light comes on. You shut down and go to inspect and find that the temp sensor probe ground wire came disconnected. The problem gets fixed and 2 months later on a flight with the CEO and board of directors of Rothbard Steel on board you launch into low IMC. 200 feet up the fire warning light comes on on the right engine but there is no smoke or any evidence of fire from visual inspection. Do you:

1. Immediately shut it down, blow the bottle and approach back into the airport at 200 and 1/2.

2. Keep the engine running due to the previous incident and no secondary indication, no smoke or anything. After all, it's at minimums and the weather where you are going 100 miles away is clear.

3. Shut it down, blow the bottle and continue on to your destination even though the wing spar could have been weakened if there were a fire.

The bold tells you all. If there's no evidence of a fire with a visual check and check of the instruments, I wouldn't be so quick to honor just the light itself, esp in the WX conditions you describe. So why would you do #1 or #3?

 

[denver]

You could have a fire so hot that there is no visible smoke. Or maybe it is hard to tell because you are in the clouds.

Or instructors at Flight Safety say to do it.:laff:

 

[///AMG]

Boldface may tell you to shut the thing down and blow the bottle, but I think the whole "no fast hands in the cockpit" has a different and important connotation here. I wouldn't personally be too quick to shut down what appears to be a good motor in low IMC or other high tasking environments unless I was damned sure that it was legit. Get above the weather, monitor the engine instruments, and I personally think that a prudent pilot would then honor the light and shut it down anyway once the situation was a little bit more under control (ie you are safely away from the ground, and in VMC). Now if you started seeing secondaries, then that is a no-brainer. Terrain avoidance and getting your nose pointed in the right direction first in that case would be the big ticket items prior to making any hasty decisions, but even an engine fire doesn't have to be an instantaneous action item. Airplanes don't just blow up from burning engines right away, even if it is startling and potentially catastrophic.

I know a guy who had what turned out to be a false alarm fire light a while back, and in a knee-jerk reaction, quickly shut it down and blew the bottle. Didn't really evaluate whether the engine indications were consistent with a fire, nor did he get a visual confirmation from other members of the flight. Not really a big deal in the end, aside from the maintenance headache that it caused, but it did add needless risk to an otherwise normal day. The single engine short field trap without normal braking or nosewheel steering he took (per procedures) could very easily (and has before) ended badly. Not the kind of risk I would want to take unless it was definitely warranted.

I also know of a guy who was abeam the runway, dropped the gear out of the break, and one of his motors started spewing 20+ ft flames out the back with no fire light. Loss of thrust/etc, but at that point, he was pretty much committed......no gas to take it around and troubleshoot, and was basically 30 seconds from being on deck anyway. He did the smart thing, and completed the high tasking portion of flight he was in prior to executing any sort of shutdown or fire light/bottle pressing. Just a couple anecdotes as food for thought.

 

[MikeD]

You could have a fire so hot that there is no visible smoke. Or maybe it is hard to tell because you are in the clouds.

Or instructors at Flight Safety say to do it.:laff:

Ive seen enough false fire lights to not be so quick to react. Like the old FEVER check:

F: Fluctuating fuel flow
E: Erratic engine operation
V: Visual indications of fire
E: Excessive ITT/EGT
R: Rough running engine.

If you don't have one of the above, chances are there's a false fire warning.

 

[MikeD]

Airplanes don't just blow up from burning engines right away, even if it is startling and potentially catastrophic.

Not right away, but it does depend where the engine is located. An engine fire for you is much worse than an engine fire in my old Hog.

 

[denver]

1000 feet agl would be the minimum for that for sure depending on the area maybe higher - Jacksons Hole, man that would be a bad day. Especially at MTOW in this aircraft.

I do not believe there is a way to test the system if the fire light trips due to an other than overheat condition. It would be nice to be able to hit the test button and confirm that it was a false alarm.

 

[///AMG]

Good thing to think about along with the rest of your departure prep. "Where do I need to be before I can really go head's down and fix a problem, and how can I get there quickly?"

 

[denver]

F: Fluctuating fuel flow
E: Erratic engine operation
V: Visual indications of fire
E: Excessive ITT/EGT
R: Rough running engine.

That's good info! Common sense really but nice of you to group it into an acronym. Is that air force?

Thanks

 

[///AMG]

Not right away, but it does depend where the engine is located. An engine fire for you is much worse than an engine fire in my old Hog.

Good point, but even for me, history has shown that very few Hornets have just exploded from engine fires. I'd probably be a little more concerned in the OP's aircraft than mine honestly, as I don't really know how quickly burn through would affect structural integrity, and of course both you and I come from ejection seat backgrounds so that might give someone a few more minutes to really evaluate something like this.

 

[MikeD]

That's good info! Common sense really but nice of you to group it into an acronym. Is that air force?

Thanks

Yeah. And for engine restarts airborne, do not do them if you encounter any of the "3 F's": Fire, FODed or Frozen.

 

[MikeD]

Good point, but even for me, history has shown that very few Hornets have just exploded from engine fires. I'd probably be a little more concerned in the OP's aircraft than mine honestly, as I don't really know how quickly burn through would affect structural integrity, and of course both you and I come from ejection seat backgrounds so that might give someone a few more minutes to really evaluate something like this.

Its not about blowing up necessarily. It's about the fire itself. In your Hornet (as well as an F-15/16, A-7, A-4 etc) when you have an engine fire, your actual airplane is on fire, simply due to the engine location. If persistant, you'll be making a nylon letdown in short order. In my old Hog, an engine fire was more an annoyance.......an emergency, yes.....but the engine is out on a pylon and I don't really have a fuselage fire. If it gets bad enough, chances are the engine will just burn itself off the airframe and drop away, and I'll have to trim a bit more aft following that.

 

[///AMG]

Its not about blowing up necessarily. It's about the fire itself. In your Hornet (as well as an F-15/16, A-7, A-4 etc) when you have an engine fire, your actual airplane is on fire, simply due to the engine location. If persistant, you'll be making a nylon letdown in short order. In my old Hog, an engine fire was more an annoyance.......an emergency, yes.....but the engine is out on a pylon and I don't really have a fuselage fire. If it gets bad enough, chances are the engine will just burn itself off the airframe and drop away, and I'll have to trim a bit more aft following that.

Fair enough.....and a keel fire in the Hornet is certainly nothing to disregard.....I'd be on deck faster than ASAP if that were the case

 

[MikeD]

Fair enough.....and a keel fire in the Hornet is certainly nothing to disregard.....I'd be on deck faster than ASAP if that were the case

Yeah, its just a matter of design. Where fighter type aircraft have internal engines; the vast majority of jets have pod mounted engines of some type. So for a fighter, things have the potential to go from bad to worse faster; but I fully agree that the hollywood "instant explosion" isn't something thats a reality to happen.

 

[Bandit_Driver]

It's a tough call but is almost always better to error on the side of caution. On the 727 is a no brainer. Cancel the bell, check essential, Get to accelertion altitude, speed up, cleanup, pull the QRH out and follow it all the way through the engine shutdown. Blowing the bottle may not be necessary if the fire light goes out after you pull the handle.

Tail Pipe hot and engine fires in the Saab are pretty much the same...You are shutting down and returning... an engine out approach should be a non-event. I don't have a lot of time in a 421 but S.E. work wasn't that bad even at moderate weights.


IMO the time you ignore a fire light is the one time you will get burnt

 

[ryan1234]

So there you are doing engine runs for the un-metered fuel flow adjustment in a Cessna 421 and the right fire warning light comes on. You shut down and go to inspect and find that the temp sensor probe ground wire came disconnected. The problem gets fixed and 2 months later on a flight with the CEO and board of directors of Rothbard Steel on board you launch into low IMC. 200 feet up the fire warning light comes on on the right engine but there is no smoke or any evidence of fire from visual inspection. Do you:

1. Immediately shut it down, blow the bottle and approach back into the airport at 200 and 1/2.

2. Keep the engine running due to the previous incident and no secondary indication, no smoke or anything. After all, it's at minimums and the weather where you are going 100 miles away is clear.

3. Shut it down, blow the bottle and continue on to your destination even though the wing spar could have been weakened if there were a fire.

Option #4: Just run to the back, pop the door, and bail out... on your way out, tell the CEO that if he knows anything about airplanes... he may want to take a peek in the cockpit or find a 'chute.

 

[ryan1234]

In my old Hog, an engine fire was more an annoyance.......an emergency, yes.....but the engine is out on a pylon and I don't really have a fuselage fire. If it gets bad enough, chances are the engine will just burn itself off the airframe and drop away, and I'll have to trim a bit more aft following that.

"Yeah...hey tower... how are ya? Gonna be a little late... just melted off an engine.... no big deal really... just put a little more trim in, that should do the trick. Save me some fajitas... extra hot sauce on the side." - 'nother day in the life of Mike "Ice water through my veins" D

 

[Pilotforhire587]

If the engine is still producing power I am gonna get to a safe altitude, clean up, and then probably shut it down... Being 121 not I would run the checklists but I am assuming a 421 is 91. Once I shut the engine down I am gona return to field... Now ask me what I am gonna do when I come back around and shoot the ILS back in, the weather was reporting 200 and 1/2 but when I get to 200 on the glide I don't see anything.

 

[drunkenbeagle]

If the engine is still producing power I am gonna get to a safe altitude, clean up, and then probably shut it down... Being 121 not I would run the checklists but I am assuming a 421 is 91. Once I shut the engine down I am gona return to field... Now ask me what I am gonna do when I come back around and shoot the ILS back in, the weather was reporting 200 and 1/2 but when I get to 200 on the glide I don't see anything.

Engine fire (confirmed)? I am cutting the fuel and taking my chances... Seen enough burn units to know that ain't the way I want to go.

 

[MikeD]

IMO the time you ignore a fire light is the one time you will get burnt

I don't say ignore, just that if the FEVER produces nothing and the situation is one where you need the engine such as was described, then shutting down an engine that might not have a problem, may create a different problem for no reason.

Two stories:

1. UH-60 flying a flight. Gets an APU fire warning light both on panel and on T-handle. There's a boldface and the PNF immediately executes it without first confirming anything. Thing is, the APU wasn't on. And the fire warning sensor was hit by sunlight at just the right angle. T-handle pulled did nothing but arm the bottle, and discharged bottle was a waste. It's like "c'mon man......if the APU was never running, what would make you think there'd be an APU fire back there?"

2. Am in USAF UPT oh so long ago. In T-37s, there's this student we have from the Mexico Air Force. He gets the stand-up Emergency situation for the day. Situation is that he notices low oil pressure on the #1 while in the practice area. He says he'll follow the checklist, shut it down, and recover to the field. As the EP progresses and he's single engine, he gets a steady light in the #2 engine T-handle while on 8 mile initial for the overhead with associated high EGT and fluctuating fuel flows. In the Tweet, the fire handle light is twofold: if it flashes, it's an overheat; if it's steady, it's a fire. Now, one thing with an engine shut down for low oil pressure is that you can restart it if you like and use it if absolutely necessary. So he decides to shut down the #2 engine and eject. When asked why he didn't decide to restart the #1 first before shutting down the #2? His answer: ".....if I restart the #1, I might damage it because it's low on oil. So Im going to eject instead..."