FSS System Flashcards
Fire detection is provided by what type of sensors are in the N2 protected areas?
Thermal
What type of sensors are in the FE 1301 protected areas?
Optical for A models (also in B models, but detection only no protection)
The automatic nitrogen discharge function is activated when any one of the four Engine Start switches is in _____ or _____ and the CPU receives signals from the engine nitrogen FSS automatic discharge relays.
Run; start
Where does N2 discharge? What is the N2 capacity & storage arrangements?
Discharges in unmanned areas only; capacity of 750 lbs per dewar; 2 dewars per airplane
How many nitrogen dewars are on the C-5M?
2 (located in the wing roots aft of the rear wing beam)
Each dewar has a capacity of?
750 lbs
What is the minimum nitrogen allowed for use for firefighting capability?
250 lbs
Is nitrogen required to be onboard for flight?
No
How many total FSS zones are there?
Twelve
Which zones have automatic nitrogen discharge capability?
Left Outboard Wing (Zone 1)
Left Inboard Wing (Zone 2)
Right Inboard Wing (Zone 3)
Right Outboard Wing (Zone 4)
When are the automatic zones armed for capable discharge?
The automatic discharge function is armed through the engine nitrogen FSS automatic discharge relays when an Engine Start switch is placed in the RUN or START position.
Can you manually discharge nitrogen into zone 5 while it is being automatically discharged into zone 4?
Yes
If more than one zone detects a fire, what is the priority system of zones 5-12?
There is a priority system for zone 5-12 alarm pushbuttons. Depressing any of these pushbuttons to the right or below a pushbutton that was previously depressed will cancel out the previous signal
What indications do you have when a fire has been detected?
FSS FIRE Warning displayed on the MFDU, a MASTER CAUTION annunciation, and an audible alert
In zones 1-4, what will happen if a second auto discharge starts while the first one is still discharging?
The second automatic zone will discharge N2 for the remaining time of the first zones 45 second time period. At the conclusion of that cycle, the second zone will then start up it’s own auto 45 second cycle.
Can you simultaneously discharge in zones 1 through 4? What about zones 1 through 4 AND one zone within 5 through 12?
Yes; Yes
Describe the priority system of the zone alarm pushbuttons?
Zones 1 – 4 are not part of the priority system when a fire is sensed in any of these zones an auto-discharge occurs
Zones 5 – 12 right and down has higher priority, but 5-12 have no priority effect on zones 1 – 4
Simultaneous discharge can occur in zones 1 thru 4 as well as 1 thru 4 and one zone in the 5 – 12 range
In zones 5 thru 12, N2 must be manually discharged and will only occur in a single zone in the 5 – 12 range
Does the battery need to be on to discharge N2 from the nosewheel well FSS panel? Why?
No; It is hot-wired to the hot battery bus when the FSS arming switch in the nosewheel well is in the POWER/ARM position
What is the elapsed discharge time from the Engineer’s FSS panel? Nosewheel FSS panel?
45 seconds; continuous
If a zone discharge in zones 5 - 12 has been started manually and subsequently a zone alarm light goes on in one of the zones 1 through 4, how long will it discharge?
Zones 1 - 4 will auto-discharge and continue for remainder of initial timer started by zones 5-12; it must subsequently be discharged manually for further operation
What if you accidentally hit a wrong, higher priority FSS button?
Place arming switch to PANEL SAFE then to ARM, then press correct button
Which zone button located on the nosewheel well FSS panel in not operable?
Cargo/Center Wing Avionics
What areas are protected by the pushbuttons on the nosewheel well FSS panel?
Left wing, right wing, underfloor forward, underfloor aft
How much can the N2 leak and the system still be considered “good”?
50 pounds per DEWAR in 12 hours; allow 1 hour after servicing for stabilization
You are departing on a mission from Dover AFB, how much N2 should you have?
650 lbs / DEWAR minimum
