Offshore Fire Warning
Joined: Apr 2004
Posts: 55
Likes: 0
From: Canada
Ah Yes Nick,
What we see here is Jean Luc using his "Immediate Actions" for Romulan Battle Cruiser within 10 parsecs....During the commercial break, Number 1 will be told to get the checklist out and go through the "Subsequent Actions". But we never get to see that!!!
What we see here is Jean Luc using his "Immediate Actions" for Romulan Battle Cruiser within 10 parsecs....During the commercial break, Number 1 will be told to get the checklist out and go through the "Subsequent Actions". But we never get to see that!!!
Joined: Jul 2004
Posts: 93
Likes: 0
From: North bound
Great thread, need to get it going again.
In the Flight Manuals I have come across, I have never seen a specified time peroid before you use the second fire extinguisher bottle.
I tried to get an answer from Sikorsky once about getting a recommendation for the system that is in the S76, but they declined.
The emergency checklist in the S76 says "If fire persists - use reserve bottle".
What is that 10 sec? 30 sec? long seconds anyway.
It varies depending on many factors I'll guess, type of detector, size of engine bay, manufacturer????
Anybody have a suggestion, or experience I'd be glad.
In the Flight Manuals I have come across, I have never seen a specified time peroid before you use the second fire extinguisher bottle.
I tried to get an answer from Sikorsky once about getting a recommendation for the system that is in the S76, but they declined.
The emergency checklist in the S76 says "If fire persists - use reserve bottle".
What is that 10 sec? 30 sec? long seconds anyway.
It varies depending on many factors I'll guess, type of detector, size of engine bay, manufacturer????
Anybody have a suggestion, or experience I'd be glad.
Joined: Apr 2003
Posts: 3,012
Likes: 1
From: USA
collective bias,
How to measure persistence? The fire supressant only creates a fire snuffing environment for a few seconds. If the fuel and ignition source are still available at the end when the gas is scavenged out by the normal airflow thru the compartment, the fire will reignite. That is why you shut off the firewall valves and shut down the engine first.
If the first bottle doesn't work almost immediately (several seconds?) then ready the second bottle. Recall that you have minutes even if the fire is raging (great theory, right? Imagine at night, overwater, how long 10 seconds of a screaming fire light seems!)
Exactly how long to wait? It is impossible to script all the possible fire scenarios, thus you can't really expect a procedure. Theoretically, the first fire can't happen. Theoretically, the shutoff of fuel/oil and engine should be enough. Theoretically, the first bottle should be enough. Now ask for precisely how long to wait for the second bottle.
Not too long.
How to measure persistence? The fire supressant only creates a fire snuffing environment for a few seconds. If the fuel and ignition source are still available at the end when the gas is scavenged out by the normal airflow thru the compartment, the fire will reignite. That is why you shut off the firewall valves and shut down the engine first.
If the first bottle doesn't work almost immediately (several seconds?) then ready the second bottle. Recall that you have minutes even if the fire is raging (great theory, right? Imagine at night, overwater, how long 10 seconds of a screaming fire light seems!)
Exactly how long to wait? It is impossible to script all the possible fire scenarios, thus you can't really expect a procedure. Theoretically, the first fire can't happen. Theoretically, the shutoff of fuel/oil and engine should be enough. Theoretically, the first bottle should be enough. Now ask for precisely how long to wait for the second bottle.
Not too long.
Joined: Jul 2004
Posts: 93
Likes: 0
From: North bound
Nick
Good comments.
Not really an answer though, I'll quess that's because there is no absolute answer. If I read you right you should use the second bottle in about ten seconds - thats fair, given the quick reaction of the S76 detectors. The scoop on the side of the engine cowling most also do it's best to blow away all the extinguishing agent rather quickly.
Speaking of the scoops.
Why was the Arriel engine cowling scoops air direction changed from the Allison, to get better function of the extinguisher? or just because of a diffrent heat source?
Good comments.
Not really an answer though, I'll quess that's because there is no absolute answer. If I read you right you should use the second bottle in about ten seconds - thats fair, given the quick reaction of the S76 detectors. The scoop on the side of the engine cowling most also do it's best to blow away all the extinguishing agent rather quickly.
Speaking of the scoops.
Why was the Arriel engine cowling scoops air direction changed from the Allison, to get better function of the extinguisher? or just because of a diffrent heat source?
It's not just an adventure....
it's just a job!
Joined: Nov 2000
Posts: 219
Likes: 0
From: Philippines
WOW!
What a great thread! Everyone is using common sense balanced against the check-list.
I never had any problem with what my course of action would be on the 61 or 212 because it was a No Brainer. If the light came on immediately, it was 99.9% for sure that it was a false indication. If it started to glow dimly then get brighter, it was the full meal deal!
The 76 is a different animal. Because it uses IR instead of heat, it will only come on immediatly not slowly so even if you are having a bad electron day and the system is just giving you a false indication, unless you are VMC where you can possibly visually confirm or rule out a fire, you are committed to the Check List. Which means, OEI and a healthy dose of that Tri-Bromo whatever crap in the bottles going into the atmosphere! Nasty stuff!
Cheers,
OffshoreIgor
What a great thread! Everyone is using common sense balanced against the check-list.
I never had any problem with what my course of action would be on the 61 or 212 because it was a No Brainer. If the light came on immediately, it was 99.9% for sure that it was a false indication. If it started to glow dimly then get brighter, it was the full meal deal!
The 76 is a different animal. Because it uses IR instead of heat, it will only come on immediatly not slowly so even if you are having a bad electron day and the system is just giving you a false indication, unless you are VMC where you can possibly visually confirm or rule out a fire, you are committed to the Check List. Which means, OEI and a healthy dose of that Tri-Bromo whatever crap in the bottles going into the atmosphere! Nasty stuff!
Cheers,
OffshoreIgor
Joined: Jul 2004
Posts: 147
Likes: 2
From: Huntsville AL
Well not that anyone wants the mechanics perspective but...
I say if you can get it home safely and let me fix it ...great, but if you for one second have doubts about it I would rather have to fish the machine out of the drink and bring you home wet and in one chunk then to have you push your luck and get the dreaded phone call about your aircraft going down and no survivors. The pilots and mechanics may pick on each other worse than any brother and sister the world has ever known but we always worry about you guys.
As for common sense that even works on our side of the house. Not all of lifes questions are answered in the almighty maintenance manual. Luckily for us we can make a decision always on the side of saftey and only cost down time and parts.
Fly safe!
I say if you can get it home safely and let me fix it ...great, but if you for one second have doubts about it I would rather have to fish the machine out of the drink and bring you home wet and in one chunk then to have you push your luck and get the dreaded phone call about your aircraft going down and no survivors. The pilots and mechanics may pick on each other worse than any brother and sister the world has ever known but we always worry about you guys.
As for common sense that even works on our side of the house. Not all of lifes questions are answered in the almighty maintenance manual. Luckily for us we can make a decision always on the side of saftey and only cost down time and parts.
Fly safe!
