Scavenging a crashed 777: for a book
 

Hi, I'm writing a book of fiction that involves a slightly damaged 777 that landed on a primitive island. I've been lucky to be in contact with a 777 pilot to get his input, but there are a lot of technical questions he doesn't know. Hopefully, some of you experts will answer my questions.

Appropriate title for an aircraft engineer?
One of the PAX is on the 777 in order to fix a 757 that is broken elsewhere. What is this person's correct title? Is it "Aircraft Engineer"? Or, Maintenance Engineer or something else? I'm assuming the person is about 35 years old and would be fairly knowledgeable regarding all the plane's systems.

Emergency radios on the raft - can you talk with them?
I know each raft has a radio set to 121.5Mhz, the question is if they just emit a homing signal or if you can talk to anyone else using one of these?

Galley hot water boiler
I'd like to use the hot water boiler as a pressure vessel to generate steam. My question is how large are these boilers (gallons) and how many a 777 is likely to have.

Cabin printer, cockpit printers
Are these regular 8.5 x 11 inkjet printers? Or dot-matrix? Or what? They would be valuable, at least until their ink ran out. Are supplies typically carried on board?

thanks!

LAME, Licensed Aircraft Maintenance Engineer, AMT Aircraft Maintenance Technician in the USA.

No they beep only. This is called an ELT, there is generally one on the aircraft and others in emergency rafts.

Maybe a few liters, not sure about quantity in craft.

Probably 8 1/2 wide but it is on a roll with perforated seams. They are thermal printers.

Thanks for the feedback.

Do you know if there is a hand-held VHF radio typically on the aircraft? I see the ground-crew with them, but does a unit remain on the aircraft?

Typically not, yet on battery power a static inverter converts dc to ac and one ships radio may be operational.

There are variants of emergency radio which do have built in microphones and allow voice on 121.5. The use of the option is not encouraged, as it eats battery life. Some variants of 777 may have them fitted. Most modern units transmit location (GPS co-ordinates) on 406 MHz also, although some still don't - the odds are that anything fitted to a 777 will.

Typical units:-

http://www.transair.co.uk/sp+Kannad-...egra-ELTs+4010

http://www.sportys.com/pilotShop/product/16431

G

I like where your imagination is taking you :cool: Except 1 thing: B777's don't crash unless you make it crash :)

But to continue with your story, you'll have to decide how damaged it is (and what caused it), do you still have battery power (for a short time anyway)?
If so, you'll have radio.
BTW they say the battery lasts about 30mins on a flying/systems powered plane.

Coffee makers have a boiler of about 1ltr, depending on aircraft configuration there are about 10-14 on board. They run on electricity (unless you want to boil the water on a campfire :8)

Good luck

Some more background:
- The plane doesn't crash, they try to land it with wheels up on the water and "slide" it up onto the beach. It mostly works, except for the tail section which fractures, but remains attached. Minimum loss of life.

- Some fuel remains, they didn't ditch it all. Possibly 1,000 gallons.

- Engines are DOA, but the RAT and APU should be functional, the engines remained attached and were shut down on impact, but they did take in quantities of seawater and beach sand. I don't expect them to be operational and I can't imagine the value of getting them to work.

- They have used the alternator and a bike from cargo to build a windmill. Doesn't produce much, but enough.

- They will have to figure out how to build a steam-powered electrical generation eventually. I'm figuring the boilers might work for that. I was hoping that the tanks used for water/waste could be turned into boilers, but it seems they are made of carbon-fiber? They don't seem to be aluminum or SS.

- Are the reservoirs used for oil and the fuel tanks made of carbon-fiber too? Any large containers that might be made out of SS?

- Thanks for the details on the 121.5Mhz. My pilot friend that flies 777 mentioned he thought they had voice, I didn't know if he was mistaken or not. I guess my 777 will have those types of 121.5Mhz radios/beacons.

Again, I like your thinking, mate :ok:
You're not stupid and doing the research, I hope we can help (don't count on me too much;) )

Watertanks (3 of on 777-300) are fibreglass
Wastetanks (2 of) are carbon fibre, so both are good for storage (although wastetanks???) or as floating devices.

The RAT might survive the impact/landing but only if it remains retracted (it deploys from the bottom of the plane).The RAT deploys automatically when both engines stop....so be aware.
Bare in mind the APU needs fuel to work (they use about 200+ kilograms per hour) the fuel pipe runs under the floor so you might want too leave that intact.

The oiltanks, sit on the engines, are made of casted aluminium, probably melts.....

O, and about the fuel; they dump it (jettison) and ditch the plane

I probably go too much into details and I keep thinking about a movie i.s.o. a book (hope for you one day they'll make a movie of it), forgive me for that.

And again, my beloved Triple doesn't fail :}

Thanks for the clarifications. Too bad the APU uses so much fuel to run, that would be an easy win.

I wonder if the APU could eventually be converted to run off steam power? It's a turbine after all. Maybe with some modifications? Of course, the modifications would have to be made with a limited set of tools.

Kenpimental - Hmmmm ... you do know this plot has been done before, in both book and film form, don't you?? :rolleyes:

http://media.apunkachoice.com/image/...mage-37157.jpg

Yes, familiar with that. Of course, my plot is very different. I haven't revealed it completely. There is certainly not going to be any effort to make another airplane to fly people off the island. They are stuck where they are and must make the most of it.

And no, it isn't a version of, "Lost" either, though both happened on an island. The island is of no major significance. I plan on making the 777 more of a focus in this story. More McGyver than the impossibilities of Lost. Of course, there is an interesting twist, but that can't be revealed. ;)

Steam engine and bike alternator.... Not alot of current there. I'd go for the generators in the engine or APU. Then you might have enough juice to annoy everyone nearby with a spark gap transmitter. This is assuming the radios are inop.

Well since the airframe is pretty much in one piece, the 406 ELT would have gone off and rescue will be within a day or two at most.

When I traveled a lot, I took a portable printer with me, maybe one of the pax did the same? Check the cargo, maybe someone was shipping a small diesel generator (they will run on jet A) if you want a more "McGyver" kind of thing, and a tight power budget to boot, have a box of thermocouples in the cargo. Strung together with any kind of a heat source and you can get some power.

Check out how the RTG's work in spacecraft like Voyager or even some Russian lighthouses worked for the idea.

There is no hope of rescue. They are on their own. It's not exactly the world as it exists today. Sorry if that's confusing.

There are thermal printers on the plane. I believe there are two of them. I'm not sure about the stability of thermal paper, so it's probably a good idea for someone to bring a portable ink-jet printer.

I'm hoping to convert a gas-powered engine over to steam. I know it can be done. I have to figure out what kind of simple gas-powered engine would make sense in the cargo hold. It seems to be "cheating" to have a small diesel generator sitting on the plane ready to go. I want more McGyver than that.

Thermocouples seem a little forced. It would be pretty random for them to be on the plane.

Right now, I don't think I'll need more thank 1KW per day generation. A windmill will do that. They'll want a steadier power source than wind, which is why steam is the next logical step. Best case would be that steam could drive the APU, but that might require super high pressures and volumes that are difficult to generate McGyver style.

But thanks for the ideas! Please keep them coming.

Don't overlook the possibility of 'scavenge finds', perhaps things from discovered crashed planes from a war in the past, or things that get washed ashore (can be tied in with a storm). Such things could fill in for items not available from the plane to make your story plans work. I'm a sucker for a good realistic story, kudos on doing the research!

Thermal paper actually keeps for quite a long time if kept tightly wrapped, and stored in a cool dark place. I have some that is over 20 years old, and it's still usable.

There will be plenty of intact pressure vessels all around the plane that can be used to store steam (engine oil tanks, potable and waste water tanks even made of fiberglas, and last but not least fire fighting tanks with a squib still under pressure).

The problem is the boiler itself not blowing up. I would use a hydaulic piston as the boiler enclosure.

Course there are also all kinds of stuff in the shipping containers in the hold including tyres under pressure which could power the many micro-turbines like engine starter motors etc.

I bet if you managed to buy a scrapped B777 (Asiana) you could ship it to an island and populate it with volunteers to sort these questions out pretty damn quick.

Q1: Are there fire-fighting equipment on the plane? If so, of what form?

Q2: How big is the hydraulic piston you're talking about? If there are hydraulic pistons, then I think a primitive steam engine might be possible using them?

Q3: Are there any tools that you'd expect to find on a plane in the normal course of events? I'm assuming there aren't any - except for what the AMT is bringing with her to fix a 757. A hacksaw is going to be vitally important to their future...

I'm here at the Smithsonian and there is a museum which shows all sorts of old steam generators, electrical generators and early inventions. Good material!

You'd need a locomotive boiler to produce enough steam to run the apu, even if it runs at all as white hot dry gas requires somewhat different fluid dynamics than warm wet steam. You don't get anywhere near the volume or pressure of steam from a "primitive boiler". Anyway, why do all that when you have 1000gal fuel?

Diesel generators are seldom carried on passenger flights I fear. They are far too heavy- you buy them where you need them.

You deployed the RAT. It will have been destroyed in the ditching.

Aircraft generators are far, far too big, heavy specialised and and complex to run off a heath robinson windmill I think, the RAT gen might just work (if it miraculously survived) but you're going to need a machine shop to modify the gearing/drives and build the windmill which would have to be pretty big to produce the power to drive even the rat gen. Did you have a machine shop in the hold too? Also on a modern aircraft like a 777 gennys are controlled by black boxes elsewhere. They produce 400v ac. Did the inverters miraculously survive the salt-soaking too?

No tools on a 777 unless in baggage. Few aircraft mechanics would carry a hacksaw in the sort of "light" toolkit they'd use on a short fix-it trip. Its just not a tool used in aircraft maintenance.

On a busy 777 someone is going to have a satfone in their pocket

I fear you'll have stretched credibility far enough (and then some) just by ditching at sea and managing to slide it up the beach. All the rest is making it become comedic.

If you have to do the Flight of the Phoenix stuff leave out the seawater at the start is my advice, and even then tread very very gently, a digitally controlled 777 isn't a tin and rivets Boxcar!

I used to operate as a flight mechanic, this could be a charter aircraft, you would have a Maintenance REP (flight mech) on board with a portable personal tool box in a main deck closet and a FAK, fly away kit in one of the belly holds. This has contained in the past several sections of flexible hose, a 60 tonne jack, pipe swaging kits and sections of pipe. And a few belly cans full of every part (mostly electronic boxes) that if failed could ground an aircraft. This is done to allow a charter service to be anywhere at anytime w/o ground support. they are commonly used by sports teams, oil companies, cruise lines, casinos the big business right now is the military.