Adlerdriver

..........$

JohnBurke

Can't be, or aren't? Economics.

I entered the main deck once to find that it was container after container of lithium batteries. I looked into the containers and found they were stacked two pallets high with cases of lithium batteries. Each pallet had a large sticker that stated "do not stack." I refused the shipment and required that half the pallets were removed. The company and shipper were upset, to say the least. I took pictures and forwarded them. Next time a shipment came up, the labels were removed.

galaxy flyer

The C-5A models had 1300# of FE1301 in 26 bottles (IIRC) to flood the cargo with basically halon. Whether it was ever used, I can't say, but it was removed from the B-models. I would guess firing that much halon would kill any fires; occupants would probably need O2 until the cabin was ventilated.

GF

JamesNoBrakes

Well, they might catch on fire for one!

decrabbitz

We (Fx 777) were having this conversation mid-Pacific last month. Main deck fire checklist has you stay at fl250 unpressurized until near airport, could be hours. Recent tri-annual cbt training said that with cargo fire, history shows you have at max, 20 minutes to live. Kinda doesn't jibe. You make a distinction in your post between cargo fire and lithium battery fire--how do you know what you have? Book says don't go look.
Based on onboard fire history (20 minutes max till game over), would the prudent thing be to descend to 1000'agl - no matter where you are, and prepare for ditching/highway/dry lake bed landing? I don't think I want to be at fl250, hoping the fire is going to starve (not possible with lithium) when the 20 minute timer runs out..
Thoughts?

Hetman

Surface transport is the solution. Once the supply pipeline is established, the "need" for air transport is obviated.

Adlerdriver

I claim no expertise in fire fighting game plans. Only what I've thought of (after the occasional post nightmare shakes) or crew discussions as you mentioned.

I do make a note of LI battery locations during pre flight. So, I would at least know if they were on board or not. Depending on which system was alerting me, I may be able to identify a specific position(s) involved with the fire and have some idea of whether LI batteries were involved or not. Not much can be done about the possibility of undeclared DG, but we have to start somewhere.

In the absence of known LI batteries, I think I would be more inclined to roll the dice and let the low O2 suppression option on the main deck and/or lower cargo class-E compartments suppression agent get me to a suitable field. I'd caveat that with the fact that I'm damn sure gonna go back and do my best to assess he situation regardless of what the book says. I think the "book" might be saying going back to fight the fire isn't the best options. Going back to look? That seems kind of critical to me. Especially if I need to determine if what I've done so far (main deck suppression/FSS) appears to be working. I've got the rest of my life to figure out the nature of the fire and if it warrants a water or off-field landing. That's a pretty big decision to make blindly when additional info might be fairly easy to obtain.

JohnBurke

One went below in UPS 6 to have a look. He never came back.

decrabbitz

All good points. But if you are going to roll the dice/bet your life on the low O2 suppression route, wouldn't it be better to climb as high as you can go (MAX ALT) rather than FL250? Sure, there are possible physio problems unpressurized at the higher altitude, but versus burning up....

My question is what is the harm in an immediate descent to 1000 agl, and investigate/fight fire there? Fuel shouldn't be an issue because you are going to probably know your fate in less than 30 minutes. If it's not good, you're ready to ditch; if it is good, then you can climb again and you've only spent 30 minutes down low. The only harm I see is the O2 levels at 1000' vs fl250- not a fire expert, so I don't know the effect. But the RFO with a halon bottle is probably better (again, against the book) than thinner O2.

I can't remember what kind of vvi you get in a 777 during high speed descent but would guess around 5000'/min. So a ditching decision made at Fl250 is at least 5 mins away, or 25% of your remaining lifetime. If the decision to ditch starts later in the 20 minute lifetime, then its 100% of your remaining lifetime

I don't have the answer, I just noticed the discrepancy from the cbt training and have been asking others what they think...

Adlerdriver

I'm not certain if you're making reference to a LI battery fire specifically or any in-flight fire warning.
I'm not sure about this. I would suggest getting more information on the system and logic behind it's design. The 777 still maintains some measure of positive differential with a main deck smoke warning and depressurization scenario (25K altitude w/ 23K cabin altitude). I'm not sure if those altitudes were selected ONLY to deal with potential physiological issues with the crew in a depressurized situation or if there are other factors at play. There may be some unintended consequences by attempting to deviate from the QRC procedure. The pack configurations during a main deck smoke event attempt to keep positive pressure to the flight deck and hopefully minimize smoke aft of the flight deck flowing forward. With one pack off and the other in low flow to accomplish this, climbing above what is recommended by the checklist may defeat what the system and checklist have been designed to accomplish. Though, as I said, I'm not certain of that.

To your other points:
Not sure if you're advocating the descent plan with any fire warning or something specifically tied to LI batteries known to be involved. If I am hours away from a suitable field, an off airport landing or ditch decision isn't going to be my starting plan. I would advocate an attempt to gather as much information as possible about the situation before considering those options. The lower cargo compartments are designed to buy some time and have the best chance (IMO) of successfully suppressing a fire while we get to a suitable field. Perhaps the main deck FSS in combination with the "factory" system using depressurizing/airflow control is working as advertised. Maybe the position involved has the fire retardant bags (make a point of asking if you don't - they're used regularly).

Because of the nature of the LI battery threat specifically, I will probably be less likely to rely on our current suppression methods if I'm certain they're involved. Either way, if we can determine the situation is deteriorating or already out of control, I think your plan to head for the deck and prepare for more bad stuff makes some sense.

One other tidbit I recently learned. UPS is fielding ceramic cans that can contain a LI battery fire for 4 hours. As an added bonus, they are significantly lighter than the metal ones we currently use. Next time I come out of SIN with the typical load of 6K+ lbs of LI batteries, I'd sure feel better if they were in those UPS cans.