FIRE HANDLE positions

[Fall_guy]

Hi Guys, 

I was wondering if anybody knows what angle the Fire Handles are turned to (when dispensing the extinguisher).
during an engine fire.  I'm currently building a Fire Panel for the B767/757 but I'm not sure if they turn to a 90degrees, 45degrees or 30degrees.  Any info or guidance would be much appreciated.

Many Thanks
John

[Kennair]

Hi John,

I can only speak for the 777 which I think is 45.  I'll check this evening if you like.  Not sure if it's different for other models though.

Ken.

[dnoize]

i have a set of real firehandles out of a 777  (page aerospace).

Not sure if the 757/767 uses the same.

just made a few pictures to show the angle.

from the center to the left is around 27-28 degrees...give or take a few tenth of a degree

second picture shows while i measure, but not too accurate, because it was a bit of a pain to hold the firehandle + digital level with one hand and take a picture with the other, but it gives an idea ;-)

Stef

[Fall_guy]

Thanks Ken, Stef

I thought I'd seen somewhere 30 degrees, so I guess 27 degrees is in the ball park.  One other thing I forgot to ask is how high does the fire handle extend when its pulled-up (above its stationery height.

Thanks again Stef for going to all that trouble, its much appreciated.

Regards John

p.s. love the B777 Fire Handles.

[Kennair]

OK I checked our 777 last night and they move to the 45 degree position in both directions.  That's how FDS have modelled it anyway.   To activate, push button (located directly under each handle) pull up handle (about 10mm) and rotate in either direction (a bottle for each direction).  Again I'm not sure how that compares to the 57/67.

Ken.

[dnoize]

I wouldnt be surprised if boeing used different suppliers/parts (as so often).

Mine are from Page Aerospace, tagged for the 777 (came from KLM).

Just makes it easier: you're good with both 45 and 30 degrees ;-)

Like Ken i dont know how it compares to the 757/767.

Stef

[Fall_guy]

Hi Stef,

Could you confirm also that your handles pull up about 10mm? (as Ken's do on the FDS model)

Many Thanks
John

[dnoize]

13,8 mm

[Hessel Oosten]

Ken, Stef, all,

About the pushbutton.

I heard two scenario's:

1. The pushbutton needs to be pushed to have the possibility to unlock the fire handle. So straight forward. Basta.

But !

2. The pushbutton is in the manuals called "override" (OVRD)! push button:

So it can be that if there is a fire, the fire handle lights up and the pilots can turn them (as above) but there is the possibility the the fire detection system is on fire too (!) and this could make that the fire handle does not light up AND CANNOT be turned in that (bad) case.

In such a situation the OVERRIDE (!) pushbutton can be pushed, whereafter the firehandle only NOW can be turned.

Opinions ! Real pilots here with comments ?

Hessel

[dnoize]

the override button is solenoid activated.

In normal operation the firealarm unlocks the lever and you dont need to push the override button.

The override button needs to be pushed in case the solenoid has not been triggered due to a malfunction, for testing purposes, etc.

i'll post some pictures of the inside later.

Stef

[dnoize]

the white thing to the right is the solenoid. When powered it unlocks the firehandle so that it can be pulled out.
The override button has the same function as the solenoid and unlocks the firehandle when pushed.

Stef

[Hessel Oosten]

Stef thanks !

So what you are actually saying is that in case of "normal" fire (ha, ha) ONLY the fire handle should be turned (in contrary to what Ken was writing) and what I wrote as scenario 2 is in fact true (using the pushbutton in case of malfunctioning fire detection system (no unlock of fire handles) or malfunctioning firehandle).

Hessel

[dnoize]

thats correct.

In case of a fire alarm the solenoid unlocks the switch.

pulling the fire handle arms the fire bottles, closes fuel, hydraulic shutoff valves and bleed air  valves, disables trust reversers

rotating left and right discharges related fire bottle.

no need to push the override switch (wich is basically a mechanical solution to push the solenoid lock down).

The override switch is there incase the solenoid fails and for testing purposes.

Stef

[Fall_guy]

Thanks to ALL

For all your advice and an excellent detailed explanation.

John

[Kennair]

Thanks Hessel and Stef for great questions and equally informative answers.  Now all we need is the software to accurately recreate this scenario.

Cheers,

Ken.

[Maurice]

  Now all we need is the software to accurately recreate this scenario.

Cheers,

Ken.

A real fire would be nice as well to test whether the angle that the handle is turned is not off by more than half a degree or so  . After all, we are talking about saving lives here 

Maurice

[jackpilot]

Agreed   

[dnoize]

will more than gladly set fire to your setup ;-)

just kidding ofcourse

[dnoize]

on a sidenote: for the 737, Prosim737 and flightdecksoftware pretty much handle the firepanel very well (loop fault detection, testing on the firepanel logics, etc) . both can be used for fire failures and procedure training (including solenoid functionality for the cpflight/engravity firepanel).

dont know how well PM or Sim-Avionics handles the firehandles, but maybe others here can tell us.

Stef

[Maurice]

will more than gladly set fire to your setup ;-)

just kidding ofcourse

Right now, that would be more than welcome. Would be glad to get insurance money for the whole package. When can you fly over? 

Maurice

[dnoize]

lol@maurice !

That would probably make you a rich man ;-)

But i could never do that....would break my heart ;-)

[Kennair]

on a sidenote: for the 737, Prosim737 and flightdecksoftware pretty much handle the firepanel very well (loop fault detection, testing on the firepanel logics, etc) . both can be used for fire failures and procedure training (including solenoid functionality for the cpflight/engravity firepanel).

dont know how well PM or Sim-Avionics handles the firehandles, but maybe others here can tell us.

Stef

Not full functionality yet for Sim-A but it is coming.

Ken.