A350 前货舱和后/散货舱共用两个灭火瓶，1号灭火瓶在1分钟内快速释放灭火，2号灭火瓶在后续长时间内缓慢释放以保持灭火剂浓度。
对此设计，有几点疑问：
- 假设前货舱出现烟雾警告，机组按压 AGENT TO FWD，释放了1号灭火瓶，之后后货舱又出现烟雾警告，再去按压 AGENT TO AFT，2号灭火瓶会释放到后货舱么？
- 如果能释放到两个货舱，是否意味着抑制时间会会缩短？
- 如果两个货舱的货物类型相同，遭遇同样的环境，是否可能同时起火？有没有必要设计两个快速释放的灭火瓶？
空客解答如下：
- 不管是1号还是2号灭火瓶，在释放期间，如果按压另一个释放按钮，就会同时释放到两个货舱。
- 是的，会减半。
- 这种情况太极端，空客也没有遇到这种案例，所以只设计了一个满足一个货舱着火的灭火剂量。
另外空客建议如果两个货舱同时着火，为了确保剂量足够，建议只灭一个货舱的火……这一点我觉得值得再商榷。
具体请参考 Tech Request 原文：
Q:
As we known of cargo compartment fire distinguishing system of A330 and A350, bottle 1 discharges within 1 min, and bottle 2 discharges within a long time.
If fwd cargo compartment gets fire first, and later the aft cargo compartment. Bottle 1 can only discharge once, how can we deal with the second fire case. If we push the AGENT TO AFT (AFT AGENT for A330), what will happen? Will the bottle 2 discharge to both cargo compartment? And if it is, the duration of bottle will reduce and cannot cover the enough time. If it isn't, we just let the 2nd fire going on?
If there're same cargo in both compartment, which is just like medical equipment we carrying nowadays, and encounter the same situation causing fire, will them get fire one by one or even simultaneously? I don't know the probability of this extreme case. But I think there should be some way to handle it. For example, why not designing 2 fast-discharging bottle for both compartment respectively?
A:
Airbus reviewed your query, and we would like to provide CSC with the following information:
We confirm that it is possible to discharge the Agent 1 to both cargo compartments. However, the probability of the fire situation in both compartments is extremely low and Airbus has never received any report about this scenario. Therefore, the system for both Agents is designed to extinguish fire in only one compartment, either in FWD or AFT cargo compartment. If both agents are activated in the FWD and AFT cargo compartments, the bottles will be emptied within half of the designed fire suppression time.
In the case of fire in both compartments at the same time, the flight crew should consider extinguishing fire in only one compartment (either in FWD or AFT cargo compartment) in order to ensure sufficiency of the agents.
As Agent 1 is discharged with a high flow rate to the affected compartment, and Agent 2 is discharged with regulated Halon flow. The Agent 1 is discharged in order to initially suppress the fire while the Agent 2 is discharged after the Agent 1 in order to compensate the cargo compartment leakage. The purpose of this design is to maintain the extinguishing Agent concentration over a period of time until aircraft landing.
Therefore, in the case that fire occurs in another cargo compartment with the Agent 1 already discharged, the Agent 2 can be discharged. However, the amount of the Agent 2 is not sufficient to suppress fire in another compartment.
As mentioned, the probability of the fire situation in both compartments is extremely low and Airbus has never received any report. Therefore, only one compartment is considered to ensure sufficiency of agents in case of fire.
We hope this satisfactorily responds to your request, and we remain available for any additional information and assistance.
