How big are the hydraulic accumulators? How many gallons will they hold?

The problem with the container is that you've got to put feed water into it or you'll have a short run. It takes at least a gallon/minute to get any useful work out of steam power. If the boiler is pressurized to say 50psi (keeping it relatively safe) then I also need a 50+psi pump to inject the feedwater into the boiler. Can I assume the freshwater lines in the plane are pressurized to at least 40? Perhaps that could be how I get to at least 40psi.

It all suggests the minimum size for a boiler to produce 500W-1KW is going to be around 60G or so. Again, I haven't worked it out, but I've played with some steam calculators.
Steam Calculators: Steam System Modeler

You would not shut the engines down prior to ditching, they would be running until the sea water caused them to stop. The RAT would not have deployed in a controlled ditching.

Wouldn't the RAT still try to deploy if the engines stop because of seawater? I assume it would still open the hatch and drop down - though I don't know how fast the RAT deploys.

Hydraulic accumulators withstand pressures up to 3000psi, however their volume is only 50 cubic inches. They are located in the aft stab bay.

I would recommend the hydraulic reservoirs. They could easily withstand pressures over 50 psi as they are normally pressurised with bleed air. They are also fitted with an over pressure relief valve that goes off at 90psi. You could mount them directly above an open flame.

The left and right system reservoirs have volumes of 12.6 gallons and the centre system reservoir has a volume of 26 gallons. The left and right reservoirs are located in each respective engine pylon and the center one is in the right hand wheel well.

Ideal boilers for your steam engine.

Are there any hills or cliffs on your island? You could build a header tank to feed the boiler. Static pressure calculations determines each foot provides 0.43psi, therefore to supply 50psi you would require a header height of 116 feet.

re: steam boilers
OK, that's what we'll do. It's pretty flat on this island, they will just use two freshwater pumps in series. That should get them to 80psi. I hope that after this is all done, I'm producing net power!

Can someone confirm there are indeed freshwater pumps? Or, do they just pressurize the freshwater container with air or something? I just need two pumps that could push at least 1GPM and will pressurize to 40psi.

That is usually referred to as a PMG permanent magnet generator, not sure off the top of my head about wattage, frequency, voltage. The main purpose is to supply power to the FADEC, Full Authority Digital Engine Control in the event of a power failure. This supplies power to that fly by wire engine to allow a minimal level of control. Think I replaced one once on another FADEC engine, it is a small unit. They are very reliable, if they were not I could probably tell you more about them. Suppose I will go back into the books tomorrow on the GE90
.

re: PMG
I understand. According to what I read, there are two PMGs per engine? Here is my source: "Each backup generator contains two permanent magnet generators (PMGs) that supply power to the flight control DC electrical system (refer to DC Electrical System)."

I can't find any specs on the web, so if you have any, that'd be great.

re: PSA batteries
Do you know what they are referring to? Are these the same as the main batteries? "Each PSA also uses a dedicated battery to prevent power interruptions to the related flight control DC bus. The batteries have limited capacity and are incorporated to supply power for brief periods during PSA power source transfers."

There is 777 info in the public domain. Have a look here;

SmartCockpit - Airline training guides, Aviation, Operations, Safety

Thanks, that doesn't have the details I'm searching for, but it is very useful.

Ken, I'm afraid this whole thing is so riddled with unwarranted assumptions, mechanical and practical impossibilities it is turning into a bit of a joke.

Leaving aside the miraculously intact arrival you're going to remove some electrical components that have been buried in seawater and sand and attach them to a home made steam turbine.

Might I suggest a little research on a) steam turbines and b) boilers?

Using the Apu as a turbine is vanishingly unlikely to work due to the vast amount of workshop modifications needed to even get steam into it - ie removing the compressor section off a single shaft design and revealing the casings(!) plumbing the steam feed and controls ( oh yes, aircraft battery and seat springs for welding rod...) and then finding out the hard way that you'd need a boiler the size of a locomotive to produce the required amount of steam (apu probably produces several hundred KW total output, go figure your boiler size at 60gal per KW, not to mention the fuel consumption) were you planning to dig an oil well too?
Anyway, steam turbine design is very complex and extremely sensitive to anything less than ideal, they only run in a very narrow range of design speed, steam pressure and temp. There is not a chance in a million the apu would do this. It might turn but it wouldn't produce any power. Plus the lumpy saturated steam your home brew boiler would produce (50 psi? Come on! Try four to eight times that to run a turbine) would likely smash it up in no time. If by a miracle it did run efficiently it would probably over speed and self destruct without a complex governor. This is pie in the sky!

Go look at boiler design. To get the energy out of fuel requires miles and miles of fine tubing all perfectly welded with welding rods, not seat springs, it isn't just a big kettle, hydraulic tanks simply wouldn't work.

use the air starter as a turbine? Better chance than the Apu for sure but again, where are the cast quantities of steam to come from? Not continuously rated, same problems with expecting a machine designed to work on air at one T & P to work with steam at another energy level.

It's just far too far-fetched and based on boys own enthusiasm and lack of any technical thinking. Sorry, it's like that guy in the Nairobi slum who built an "aeroplane". You can't Just make up high tech engineering without any training as you go along, trying to do that with something as crude and basic as a small aeroplane was self evidently doomed to ignominious failure. Trying the same with bodged gas turbines and a kettle is orders of magnitude more ambitious and with the greatest of respect you've demonstrated a number of times your complete lack of knowledge in both engineering and physics. This is too technical a subject to be tackled in this way without it descending into pure farce.

I think some of the suggestions you've been getting here are akin to bystanders chucking food over the cliff to encourage the Lemings...

I think you have to remember this is a work of fiction, not a document telling people how to build these things. I think the standard should be "plausible" not "definitely doable". I also believe that things will work - but at an inefficient level. I'm not expecting them to jury-rig something with state-of-the-art efficiencies. To say that it is impossible to use a simple boiler to generate power flies in the face of Robert Fulton's efforts. The early steam designs were also inefficient, but as long as there is water and fuel, they can do useful work (and did).

I do thank you for challenging all of this. I'm trying to keep things in the plausible category. It's clear you think I've stepped over the line. If there is any way to help me get back to plausible in your mind, I'd appreciate it.

I have jury rigged B-17 superchargers for use as steam turbines by blocking off a 270 deg arc of blade/vanes and plumbing steam into whats left. Got the things to 20,000 RPM and about 100 hp.

Less steam and it would still work with the right nozzle area.

Let me loose in a wreckage field and I can propbably get something working.

Necessity is the mother of invention.

Thanks, that's the spirit the book is intended for. Many books just make s*it up; I'm trying to avoid that with at least some research that keeps it grounded and credible.

I appreciate all the help and the criticism too. It forces me to be even more careful in my research.

I have always loved tinkering with various bits and pieces and I love this site:

The Museum of RetroTechnology

I have little doubt that one or two resourceful people on an airliner could make good use of its resources to cobble together quite a few things mentioned on this site. Have a look, and I hope you might find something useful to your story!

As for the ditching/landing, there is the precedent of the BA 777 which crash landed at Heathrow after engine icing problems shut them down.

That's an incredible site! I'm going to get lost there for awhile. I'm sure it will be useful at some point. Thanks for pointing it out. I guess the book is destined for a "steam-punk" phase. :)

Glad you like it, I thought it might be worth a browse as your story seems to be based on improvised gadgetry and alternate ways of doing things.

My Dad is mentioned in the part about Speaking/Gosport Tubes, but I have no connection with the site apart from loving it!

Ken,
Keep it coming,the most interesting thread we've had ! One of the things about aircraft enginers/techs/mechs is that they are fixers with initiative,somtimes to our own detriment!
I did many years as a flying spanner and I used to carry my house on my back, in terms of tools.Carried a hacksaw+ spare blades and ,incidentally a hand drill - didn't always have access to pneumatic or electrical power for a drill (saved my bacon a few time!) and always carried a mulitimeter.
Suspension of disbelief is fine by me,plausability helps of course !
More power to you Ken,good luck,keep the questions coming and let us know when the book comes out !
Another thought,do pax life jackets still use salt water batteries ?
Also relatively easy to make salt water battery,plenty of electrolyte (salt water) and material to use as electrodes,you can get around low output by making a 'battery' of cells.

The point has been made that ditching directly (more or less) towards a beach so as to slide on to, and then come to a stop on, the beach is implausible because of the impossibility of judging the final descent and touchdown point to enable this to happen.

I suspect that the only plausible scenario is a very wide, very long, straight beach, with a very shallow slope seawards, and an approach angle to the beach of, say, 5%-15%. This would give a fair margin for error, with a reasonable chance of ending up out of the water, in between the water's edge and the top of the beach.

But finding that beach just when you need it for a forced landing, and then being able to position accurately for the approach and touchdown, would require huge amounts of luck.

But I don't fly B777s, and that may be a daft idea to anyone who does.

suppose the beach shelved....IE a sandy cove with a very shallow underwater slope,continuing up to the point where it transitions to flat earth..a slow approach may allow the plane to slide all or part way up the beach.....a bit faster and it goes over the hump and slaps down on to the earth, (breaking the back of the fuselage in the process.
A tropical downpour would firm-up the beach and lubricate it and the earth.

STIRLING Please, not Sterling,that's UK currency, engines can be hot air engines.....once constructed, sheet aluminium could be salvaged, shaped and burnished sufficiently to make mirrors to heatthe "hot" end. there are lots of absorbent materials aboard, fibreglass insulation, upholstery,etc to cover the "cold "end...again, panelling,etc could be used to form a sun-shelter over the "cold" end and funnel the prevailing wind, because you'd water-soak the absorbent wadding which would chill by evaporation.

http://www.bloomberg.com/image/ickB1IVzCsOY.jpg

Plenty of cars can fit into lower cargo, and flying spanner tools can manually wind the cargo doors open assuming :uhoh: no structural damage. :}

Hey people. I've been busy in other parts of the book, not related to aircraft disassembly. I'm now 90,000 words done, and I need to extract some weapons from the aircraft.

I've decided that crossbows are the simplest thing to pursue for a bunch of untrained PAX. The stock, bow will be made of wood along with the trigger mechanism. I could use other material from the plane if it made sense and wouldn't require excessive effort to extract rework.

I was wondering if the bolts (the arrows used in a crossbow) could be made out of stainless steel? Someone mentioned to me that the seats of an aircraft contain stainless steel rods? I don't know what diameter these are, or how long. My hope was that they were about 18" long and about 1/4" diameter. You'd sharpen the end of them using a stone and have a bolt. If each seat has a couple of these, then I have plenty of bolts.

If not bolts, then how about making steel tips to go on wood bolts? Are there things that might make great sharp tips with minor modification? There is plenty of hard, dense wood on this island. It would make decent shafts.

Tools available include a hand drill, a couple cordless drills, a single Dremel. Hacksaw with a couple spare blades, other basic tools. No lathe, grinding machines, forge (yet), or anything more sophisticated than hand tools.

Any help appreciated.

Ah, weapons, hobby interest !

A crossbow is a reasonably precise bit of machinery, needing reasonable manufacturing precision as well as storing enough energy to take your fingers off it if fails whilst cocked. That may be a plot device you can use ! You'd really not struggle if pulling any aeroplane apart to find control pushrods of one sort or another than could do a reasonable impression of a crossbow bolt. I doubt you'd find them in the seat.

The simplest weapon I know that is easy to manufacture and use is a spear. A spear, contrary to popular opinion, is in most variations not a throwing weapon. Basically it's a stick with a knife on the end of it, and the techniques of using a spear are very similar to those for a longsword. Historically people who weren't important enough to justify the significant expense of a sword, got a spear, which uses the minimum amount of expensive metal. There's plenty of history of effective hunting with spears - and they ARE NOT thrown. Typical length of a spear is 4-6 feet.

Knifes / daggers/ are easily cut and ground from bits of scrap metal - fighting with knives is a messy game, but they're an essential survival tool of course. A knife tied to the end of a stick is a spear! Between two people, attacking somebody with a knife takes little skill or fitness, defending against a knife effectively takes very considerable skill.


For a weapon, the next most straightforward improvised weapon would be a bola. Three weights, three bits of string / wire / rope, tied together.

After that would be a slingshot - easily made from any reasonable strong fabric, ammunition is stones.


I could teach you the basics of fighting with a spear in a few hours. Attacking somebody with a knife in 10 minutes, and defending yourself effectively against a knife in a few weeks.

Using a bola is very easy, and takes little skill, just a bit of thought and practice.

Using a slingshot is a matter of a few hours or days of practice, but is fairly intuitive.

It would take a lot of skill and time to make an effective crossbow.


Incidentally, making a bodgers lathe is pretty straightforward: http://www.greenwoodworker.co.uk/Archive.htm Where I live, up until maybe 60 years ago, people used to just go out into the woods with an axe, saw and some rope, and come back a at the end of the day loaded up with chairlegs.

G

Thanks for the info. My problem is that the PAX will have to deal with people that wear plate armor, carry spears, swords, knives and crossbows and know how to use them. Somehow, the PAX have to survive at least one engagement without being totally slaughtered.

The PAX, at this point, have spent a few months learning to hunt with spears, knives and are familiar with them - if not fully experienced.

Luckily for the PAX, there is one grizzled Iraq veteran who can train them in the basics. But, they are realistic about what they can achieve with limited training (weeks, not months before they are attacked).

They have to use their advantages (the plane, technology, defending) to deal with an attack they know is coming.

They will be able to make gunpowder where they are, but they won't do that before they are attacked. They also won't be able to set up a distillery before being attacked. Of course, they do have some Jet A fuel left...

There are fairly simple wooden designs for a crossbow on the Internet. I'm not sure what else would be effective against plate armor. I think they could build 5-6 crossbows and using them, with other defensive means, could repel the attack. I like the idea of the bola, I hadn't thought of that.

BTW, I just thought of using the snubber that holds the overhead bins. Is that a dampened piston with a SS shaft going into a aluminum body or something? If I separate those parts, and use the SS shaft, do I have my bolt? There must be a lot of those on the plane.

Having been certificating airliner galleys until recently (not Boeing though), I can hopefully shed a bit more light on the plumbing. It is designed to operate at 40psi, but is designed to take 125psi when being refilled and is static tested to 188psi. Ultimate burst pressure is supposedly 250psi, but they will take more... ;). All potable water hoses were PTFE lined and reinforced with stainless braiding, whilst waste hoses were reinforced silicone. Rigid pipes and unions were stainless steel.

The water heaters I used were four litres capacity, with a stainless steel reservoir. They have pressure relief valves and generally don't heat water above 88°C on electrical power due to the drop in water boiling temperature at 8000ft cabin altitude.

A B777 size aircraft could have easily have six or more galleys with plumbing for hot water boilers, beverage makers, coffee makers, espresso/cappuccino makers and steam ovens (Google 'airliner galley inserts').

If you need to get a higher pressure, wrap the boiler with steel wire. Look up 'flash steam' for high power steam systems with small boilers.

If you can get them out, the engines and airframe will contain thousands of bolts and studs from which tools and weapons could be made. Also, on the subject of weapons, if you have a hydraulic cylinder, some jet fuel and oxygen (bottled or generated) plus a means of making a spark, you can make one hell of a cannon!

With all the aerofoils or curved surfaces that are available (slats, flaps, control surfaces & bits of interior trim) why not build a wind turbine? You could make a peristaltic pump or motor out of a wheel and an inner tube (there must be a bicycle in most airliner holds) as some Scottish crofters did on a TV programme (The Great Egg Race).

BBC - Archive - The Great Egg Race - Cracking feats of engineering

A visit to an aircraft breakers would be a good idea to get an idea of what is available. Googling B777 suppliers will yield photos giving an idea of what is in its sub-assemblies.

I still find the crossbow an odd choice of weapon. A longbow is much easier to make if there's access to appropriate woods. and with some good training, more effective on every level (greater range, greater penetration, greater fire rate). The *only* advantage of a crossbow is that it can be operated by an untrained halfwit (or Frenchman, as they called them at Agincourt).

Swords, daggers, spears are effective against armour, because armour has gaps, and any such conflict occurs at close range. Whilst the tradition is much stronger in the east today, there are global traditions of martial arts designed for use against armed and armoured opponents. Classical Jiu Jitsu certainly does that, and here in Europe the texts that survive by Fiore, Ringeck, Silver - all describe such systems here. To a lesser extent, Philipino escrima does the same also - lesser because it's much more about dealing with bladed weapons than it is about dealing with armour.

Have you got a local western martial arts school, or traditional Jiu Jitsu dojo you can go and do a bit of learning from? In terms of your pax - in my experience at-least 1 in 20 of most populations have done significant martial arts training so a few JiuJitsuka of teaching standard, or an expert Escrimador isn't an unreasonable proposition. Neither needs any advanced engineering skill to manufacture weapons. Judo, if you were unaware, is just a sport derivative of Jiu Jitsu, and contains techniques perfectly valid against armour, although probably not against most weapons.



Incidentally, are you aware that the book you're writing already got published in 1874 under the title "The mysterious island". Not, in my opinion, Jules Verne's best book by a long way, but he was basically writing the same plot as you are by the sound of it.

G

With regard to pressure vessels, the B777 has 14 tyres each pressurized to 200+psi. There's a fair bit of stored energy for you already.

If you filled the tyre with water, and were to rig up some means of passing hot air from a fire through the wheel hub, water in the tyre would eventually boil. Don't try this at home!

Any sealable metal, ceramic or hard plastic container filled with fuel and oxygen has the potential of making a land or claymore mine if you use a battery and a pressure switch to create a spark inside. Alternatively, you could trigger them remotely, as there is no shortage of wire in an airliner. Your Iraq veteran will have seen IEDs or been briefed on them to know what is needed.

If you can find where uni-directional carbon or glass fibre is used in the structure, you have potential longbow material, There are 10 tons of Carbon fibre in a B777, so some of it should be useful if you can cut and shape it.

This may be a useful resource for who supplies what for the B777:Boeing 777 - program supplier guide

I don't know the 777 well enough, but it also wouldn't take much ingenuity to create a decent bang out of any magnesium alloy castings?

G

In response to Mechta
re: tyres
That's a novel way to build a steam engine! Not sure how it could be modified to continuously supply steam. That is my ultimate goal. Maybe it is used to store steam energy from another source. But if it doesn't have a relief valve, then it will go kaboom if you're not careful.

re: IED
Thanks for reminding me to use the oxygen as an oxidizer for a more powerful explosion.

re: carbon fiber
Yes, I'm hoping some of the panels in the plane can lend themselves to things like bows or maybe a small catapult.

re: plumbing
Thanks for all the details! I've been wondering about that for a long time. I can see the elements exist for making some form of steam boiler and/or cannons/bombs.

In response to Genghis:
re: crossbow vs longbow:
Based on my research, the longbow, while much easier to make and more lethal at longer ranges, requires way to much training. The English were such good longbowmen because they had years and years of practice. The crossbow is the fastest, most lethal weapon at a distance of 10-20 yards that requires limited experience to shoot. Especially against armor. Sure, you can get lucky with a spear from that distance. BTW, as I mentioned spears are being used, I just want something more sophisticated.

re: martial arts
Yes, I fully expect that someone will be training the PAX in these skills. However, it takes time to learn them well enough to defend yourself successfully, but thanks for reminding me to mention it as part of the "plan" for the defense force.

re: plot
I haven't revealed much, so I can understand why you might think it related. But the island is not "mysterious" in any way shape or form. This isn't an episode of "Lost".

Squawking 7600?
 

If I have the pilot squawk 7600, what do they reach for? The CDU? Do they just tap some buttons on it and press "send" or something?

Basically yes. I don't know the specific cockpit, but 7600 and enter on something on the central console.

G

Cool. Thanks for the fast reply.

http://images.flightstore.co.uk/imag...9-08429600.jpg

Looks to me that the transponder control is the small box just above the blank panel near the bottom on the right hand side. In which case, it's a case of dial each number in - marginally more time consuming. The range of numbers available for each digit is 0-7 (it's an octal numbering system). Something like this:-

http://files.abovetopsecret.com/file...eu4f1b14bc.png

Best guess on that unit - turn the bottom left knob to STBY, use the big middle knob to dial in the four digits, then back to XPDR, or more likely to the TA/RA (Traffic Advisory Resolution Advisory) setting which integrates it with TCAS (Terminal Collision Avoidance System).

Control units vary a little - here's a picture of the Garmin box in the aeroplane I was flying yesterday..

http://planefinder.net/about/wp-cont...ner-300x97.png

That one, you just press the four numbers. But that's a GA unit, airliners tend to be more integrated and we don't fly with TCAS in most baby aeroplanes, whilst it's mandatory in airliners.

G

I think I found it on the pedestal. You use a rotary knob to select the appropriate code:

Boeing 777: Air Traffic Control Transponder (ATC) & Traffic Collision Avoidance System (TCAS)

Thanks for the replies.

Yep the transponder.

So your 1000 kgs of fuel isnt going to last long.

It rotates at something like 4510 rpm and the blades are 105CM long.

So the RAT would be your best choice of power.

As for ditching close to a beach, i don't think that anyone would try this with the gear down!

Genghis/kenpimental

That's certainly where the controller sits but I'd point out that the exact choice of panel is a customer option - I certainly don't recognise the one in the flight deck overview image, and I don't recognise the one that kenpimental has provided a link to. All our 777s (200s and 300s) have a different panel design, they have a small keyboard for number entry, so you punch the code in rather than dial and FWIW on ours there's no need to select STBY before changing code.

https://c1.staticflickr.com/1/421/18...71a4af95_z.jpg

This model transponder is in our 1997 era -200's

Now that I have more time, I've gone back to my book and I'm doing a major rewrite for various reasons. I wonder if some of those that helped me in the past are still able to do so. As a reminder, I'm writing a book on an American Airlines 777-200ER that survives a ditching and winds up on a beach. Most of the crew survive and the plane is in two pieces (so never flying again), but there were no major fires. There is a "flying spanner" on board, who knows what parts of the 777 can be used for different solutions to survival problems. This is a work of alternate history and does involve a trip to the past - so the island is basically uninhabited and there are no modern support systems (no rescue teams, no satellites, no comms - other than what they can create). The people are on their own - with a 777 to dismember and whatever is in cargo/luggage.

Questions:
1) Are there more than one Auxiliary Survival Kit? Reference on a 777?
2) I need to create a water distiller, I’m wondering if the AC units on the plane could function as such. I would remove the evaporation coils (or grid?) and pipe steam through it while immersed in colder water.

thanks!
ken

That might well be a customer option..FWIW we carry 8 "survival packs", basically one for each slideraft..and ours are not made by EAM, last time I looked they were an RFD Beaufort product

OK. So you just have the ones for each slide/raft. I think I can pretend that American has a couple auxiliary survival kits on this flight.

Thanks for the response!

Some pilots watches also contain an ELT BTW

https://www.whartongoldsmith.com/wat...SABEgKBw_D_BwE