Hi everyone,
I'm working on the final draft of a feature film called LEFT BEHIND which will be produced later this year and released sometime late in 2012. A little more than half of the movie takes place on a 747 - on a transatlantic flight from JFK to Heathrow. About three and a half hours into the flight, around 1/3 of the passengers suddenly vanish. The captain turns the plane around and heads for JFK, having lost all radio contact and his first officer.
There. That's the premise.
So as I work through this, I was hoping to get a little bit of help in trying to make the experience in the flight deck as authentic as possible. I stumbled upon this site and after reading a long thread about what the crew talks about on long flights I knew I was in the right place.

Here's my first "technical" question:
Our plane is involved in a near-miss collision where there is some damage but they remain airborne. The result of the damage is that they have to dump a significant quantity of fuel to avoid a fire in an engine that is sparking. I have been having a hard time finding out if you can in fact dump fuel from one wing without draining both sides equally. There is something called a cross-feed valve, that controls the flow, but does it have to be open during flight to keep the plane "balanced".

Thanks
Paul

Quoting waterdog (Thread starter): Our plane is involved in a near-miss collision where there is some damage but they remain airborne. The result of the damage is that they have to dump a significant quantity of fuel to avoid a fire in an engine that is sparking.

You're obviously going to have to take artistic license to make the story work, but I can't think of any scenario where you would dump fuel to avoid an engine fire. There are two valves (one on the engine, one at the top of the strut where it joins the wing) to shut off fuel for exactly this reason. The only normal reason to dump fuel is to get your weight down in preparation for landing.

A more realistic option might be to have the damage from the collision rupture a fuel tank, either directly from the collision or due to debris thrown lose by the collision. That would drain the one tank (this is actually a designed-for condition).

Quoting waterdog (Thread starter): I have been having a hard time finding out if you can in fact dump fuel from one wing without draining both sides equally.

It depends on the aircraft. On a 747, manipulating the right combination of fuel pumps would allow you to dump fuel from one tank (or one wing...the 747 has three tanks in each wing + the one in the center + the tail tank on some models). However, there's no normal procedure that would have you dump from just one tank.

Quoting waterdog (Thread starter): There is something called a cross-feed valve, that controls the flow, but does it have to be open during flight to keep the plane "balanced".

The cross-feed isn't really involved in fuel dump...it's there to allow the fuel in one wing to feed the engines on the other wing if necessary. If you were forced to dump the fuel from one wing for some reason, you'd need the cross-feed to keep the engines on that wing going (using fuel from the other side).

Tom.

If they're 3½ hours out from JFK, it is unlikely the Captain would try to return JFK in order to land. There are several suitable airports much closer, for example Gander in Newfoundland or Keflavik in Iceland.


Regarding the fuel dump, it is important to remember that engines are already "on fire". That's how they work! If there is any fire that is "uncontrolled" in or around an engine, the feed valves mentioned by tdscanuck would be closed. You don't want to dump fuel you might need later.


Of course there's artistic license, but as Tom says collision damage rupturing a tank would be more plausible.

The plot sounds a bit like Stephen King's 'The Langoliers', except for the midair collision part...
If I were writing this, I would imagine that maybe the 'near collision' or glancing blow could have ruptured a fuel tank, causing the weight and balance problem, then maybe some damage to an outboard engine nacelle could cause a seperate engine fire and hydraulic failure, forcing an engine shutdown and fire bottle useage that would make for plenty of cockpit drama in your script. You could probably find some good real-world aircraft incidents as reference material if you're concerned about realism, which most movie script sadly are not.

I'm glad he's asking here, because a lot of aviation themed movies leave a lot to be desired when it comes to plausibility, realism and attention to detail. Ask here and you shall recieve! Lots of smart aviation folks at this place.

Quoting HaveBlue (Reply 4): I'm glad he's asking here, because a lot of aviation themed movies leave a lot to be desired when it comes to plausibility, realism and attention to detail. Ask here and you shall recieve! Lots of smart aviation folks at this place.

Indeed. I would add: Don't be afraid of realism. The pedestrians won't know the difference but those in the know will! Likely it won't cost anything extra either...

Quoting Wingscrubber (Reply 3): The plot sounds a bit like Stephen King's 'The Langoliers', except for the midair collision part...

That was my first thought.

There are also similarities John Varley's excellent short story "Air Raid", which begat the decent novel "Millennium", which begat the awful movie "Millennium".

Quoting waterdog (Thread starter): The result of the damage is that they have to dump a significant quantity of fuel to avoid a fire in an engine that is sparking.

You wouldn't do that to avoid a fire, only drop weight. You'd want to transfer fuel to another tank, which can easily be done, especially 3.5 hrs downroute. BUT, I think with damaged engine bits flying around out there, it's not the biggest priority. In real life, there'd be about 300kt of -60f slipstream not only between the engines and the fuel tanks, but also carrying any vapors away from the sparking or flaming engine. A fire popping up there simply isn't plausible.

Quoting waterdog (Thread starter): I have been having a hard time finding out if you can in fact dump fuel from one wing without draining both sides equally.

Well, you can do what I used to do when I had a (very non-lucrative!) career writing sci-fi and simply move the scene of the crime, so to speak. Why not have your "collision" more directly effect the fuel system itself? This way, yeah you can pretty easily dump only one side (seeing as maybe the other side is now inop.)


As an aside...

Looks like you have a degree in psychology there. Which in your case is good. You'll get your best realism, (in pretty much any type of story) by having your characters very well developed. By using a fuel system damage scenario as opposed to the more easily relatable "exploding engine fire" one, you may actually be able to work an exposition in between two pilot characters, that points out how much worse a fuel system error is than one out of four engines going blink.


I've written about seven stories that have actually seen the light of day (though only three were full length and none had production runs of more than a season...) and here's what I took from that. A story can often be best told almost entirely through inter-character exposition. BUT, you need to be careful with that. Too much and you have a reality show on paper. Not enough and you have a dry fact-dump-stravaganza.

Work out what's going on with your remaining flight crew during this emergency. Everything from how they deal with a sudden tension dump down to the totally trivial shit they forget about during the fact. Or the totally trivial shit they overwork if they're that messed up about it (I'll never forget the time, in real life, that I risked life and limb to rescue from a burning auto wreck... ...a half smoked pack of ciggarrettes!) Work your people end of the story and the rest really will just kind of fill itself in.

Good luck and let us know how it goes.

Quoting waterdog (Thread starter): LEFT BEHIND

Maybe I'm missing something, but wasn't this movie already released in 2000? http://en.wikipedia.org/wiki/Left_Behind:_The_Movie

Quoting waterdog (Thread starter): Our plane is involved in a near-miss collision where there is some damage

Ah, going with the George Carlin definition of "near-miss" here, I see....  

Quoting waterdog (Thread starter): I have been having a hard time finding out if you can in fact dump fuel from one wing without draining both sides equally.

It's possible if you move the valves around properly, as has been said, but I can't think of any reason why you'd want to - if you fill one wing tank and drain the other, you're going to have balance problems.

Quoting waterdog (Thread starter): There is something called a cross-feed valve, that controls the flow, but does it have to be open during flight to keep the plane "balanced".

Normally not - it's there for when you have an asymmetrical fuel burn (one side burning down faster than the other, or more commonly one engine that's failed and isn't drawing fuel anymore) and you want to keep things balanced.

Quoting Starlionblue (Reply 2): Regarding the fuel dump, it is important to remember that engines are already "on fire". That's how they work! If there is any fire that is "uncontrolled" in or around an engine, the feed valves mentioned by tdscanuck would be closed. You don't want to dump fuel you might need later.

   The procedure for an engine fire is to shut it down, cut off the fuel, electrics, hydraulics, pneumatics - anything going into or out of the engine. No need to dump fuel in that scenario unless there's going to be a landing weight issue (which on a JFK-LHR flight there shouldn't be, especially if you're going to Newfoundland and then turning back all the way to JFK).

Quoting Starlionblue (Reply 5): I would add: Don't be afraid of realism. The pedestrians won't know the difference but those in the know will! Likely it won't cost anything extra either...

   I can't count the number of times where movies or tv shows get the little things wrong - one post here and it would have gotten sorted out, and it would have sounded just as jargon-y for the general public.   

-Mir

Quoting waterdog (Thread starter): Here's my first "technical" question:

Cool, as an aviation enthusiast and having moviemaking as a hobby, I really appreciate you asking and sharing here, wether it is for realism or just for getting good ideas.
How about you tell us, what your requirements are? Is fuel dumping a "must" ? Or are you just searching for a plot for some dangerous, critical, high-bloodpressure action? What kind of setting/story is already "fixed" and what is still open for change and new ideas?
I agree with the others, that I would stay away from "exploding engine due to fire", as it is been used countless times (standard, nothing special) and isnt even close to reality.
By the way, here is a good list of real mid-air collisions in the past to get some ideas:
http://en.wikipedia.org/wiki/Mid-air_collision

Most interesting propably being the 2006 Gol/Excelair collision, and the 2002 Bashkirian/DHL collision.

Quoting hal9213 (Reply 9): Is fuel dumping a "must" ?

The thing with dumping fuel is that the public has heard of this, a lot, on the news. The public in general has no idea what it really signifies, but it is at least known. So you don't have to explain it. Then again you do have to explain it if you want realistic fuel dumping for realistic reasons.

With regards to something that gets the blood pumping, I think a fire in the cargo hold would make the pilots WAY more tense than an engine fire.

Quoting wn700driver (Reply 6): A story can often be best told almost entirely through inter-character exposition. BUT, you need to be careful with that. Too much and you have a reality show on paper.

Or Heinlein.   

Quoting Starlionblue (Reply 10): With regards to something that gets the blood pumping, I think a fire in the cargo hold would make the pilots WAY more tense than an engine fire.

Most definitely, especially if you are way out in the Atlantic! A fire where there is little or no suppression equipment is certainly a worst case scenario, and for a movie engine fires are now an overdone cliche. There are far more severe emergencies that you can choose from.

If you really want to have an emergency surrounding the engine but resulting in fuel loss, maybe the collision could cause an un-contained blade failure in the engine? Normally this wouldn't (or at least shouldn't) happen due to the armoured engine casing, but a collision could conceivably damage it and give you license to get shrapnel damage in any number of wing mounted critical systems (and if it is an inboard engine, maybe in the fuselage also).

Quoting travelavnut (Reply 7): Maybe I'm missing something, but wasn't this movie already released in 2000? http://en.wikipedia.org/wiki/Left_Be...Movie

LOL, I was thinking the same thing   Quite familiar with that Left Behind, and the whole book series by Tim LaHaye...

Quoting travelavnut (Reply 7): Maybe I'm missing something, but wasn't this movie already released in 2000? http://en.wikipedia.org/wiki/Left_Behind:_The_Movie

Actually, yet it was, by me. We made that movie on a very low budget and without any real Hollywood names. It was the bestselling independent film of the year and we sold almost 10 million videos/dvd's. We have decided though that the movie didn't really do what it could have done if we'd have given it a proper budget. So, we're remaking it for a full scale Hollywood release.

THANK YOU to everyone for taking part in this thread. I want very much to make this all realistic and true to life, so every word in here is valuable and taken very seriously.

Paul

Quoting Starlionblue (Reply 10): How about you tell us, what your requirements are? Is fuel dumping a "must" ? Or are you just searching for a plot for some dangerous, critical, high-bloodpressure action? What kind of setting/story is already "fixed" and what is still open for change and new ideas?

Wow, this place is great!
The bottom line is that there is now a serious risk of not reaching land before running out of fuel - so when they finally get back in radio contact, and find out the airports are all shut down, they don't have the option of flying around looking for somewhere else to go. How they run out of fuel doesn't really matter. As you said, it's all about keeping the blood pressure up in the flight deck while the passengers are busy freaking out and trying to figure out what happened.

Re the airports shut down, the vanishings are worldwide, tens of millions of people. There are planes crashing, ATC staff missing, and airports clogged with tens of thousands of passengers that were able to land but have no way of getting out of the airport with the streets all clogged with accidents and driverless vehicles.
Our pilot, thinking the vanishings were only on his plane, is not prepared for any of this. JFK, thank God I finally got through. I am out of fuel, gliding in, i need you to clear a runway. Sorry, there are twenty planes parked on every runway. Bummer.

If I can throw in the million dollar question - if you were flying this plane and half your passengers vanished into thin air, what explanation might jump into your mind? What would you do? I have watched every episode of MAYDAY and all the YOUTUBE videos I can find and I'm always shocked at how professional the crews seem to remain in the face of unbelievable stress. I can't cope with someone driving 50 in a 60 zone, imagine running out of gas at 35,000 feet!! If I'm driving home from work and my fuel light is on, I can't take my eyes off it until I find a gas station. Worst case scenario in that situation - I have to pull over and wait for CAA. I guess I wouldn't make a very good pilot - no one ever seems to get air-rage.

Quoting waterdog (Reply 14): What would you do?

Hmm, I'm not seeing a real thriller of a concept here, though I think the key issues behind a "left behind/anti-christ/divine intervention/belief" scheme is both good and somewhat plausible.

The plane would be able to land almost anywhere there is a paved surface (roads, highways, small airports, large airports, fairly smoothly with a risk of running off the end of the runway) and in a pinch, also land on water, with obviously catastrophic results - but at least they are down on the ground, to the best of their ability. Therefore an airborne crisis is not something that will excite audiences, it's been done in many ways before.

Recently, I was reading a few old Dr. Who episodes (that I barely remember as a kid growing up in Oxford, UK) and there was an episode involving not one, but TWO concordes that had somehow entered a time vortex and went back to the prehistoric era etc. etc. complicated, fantasy story, but aviation related nonetheless.

What about Millenium (the 1989 film), where the passengers are replaced with body doubles to be saved for a time travel rescue so that they can be badly needed in a bleak future of mankind. That, and the obvious Cheryl Ladd eye-candy, and the key line "Did you ask for clearance from the tower..." made it ok or so, plot suffered though.

If faith is so important, why not place the protagonists in a impossible situation where they have to, absolutely, positively have to put their ultimate confidence in God/Creator/the big guy and hope and pray it works?

If I were writing this, I would move the scenario into the near future, in space, on a deep space mission, with astounding graphics and realism in spaceflight (think Kubrik's production of 2001: A Space Odyssey) and the ultimate realization that our place in the Cosmos is nothing but a gift from ... and we need to be humble about our accomplishments and less greedy about what we can get now, from our world. After all, from Space, we can see no borders, no distinction between Earth/Water/Sky and most of all no boundaries in our respective beliefs.

(I've been modeling some space missions recently..)

'Nuff said.

Moderators, please move this to non-Aviation. And if the OP wants to communicate, he/she can use the messaging feature for contact.

[Edited 2011-08-18 11:24:46]

Quoting waterdog (Reply 14): I can't cope with someone driving 50 in a 60 zone, imagine running out of gas at 35,000 feet!!

If you run out of fuel at that height, you can glide for a long time and for a great distance, so the stress levels could be greater in other scenarios. The plane needs airspeed to fly, and altitude can be converted into speed in lieu of thrust from the engines. To really get the blood pumping (but for a shorter time so it may not work for your purposes), the engines should stop turning much nearer the ground where there are greatly reduced options and less time for evaluating them. Think of the British Airways 777 that lost thrust in both engines on final approach to Heathrow a couple of years back, they barely made it to the airport even from the final approach path.

"Airspeed is life, altitude is life insurance".

Quoting boacvc10 (Reply 15): If I were writing this, I would move the scenario into the near future, in space, on a deep space mission, with astounding graphics and realism in spaceflight

Thanks for your comments BOAC, let me just address a few things quickly;
1. this is an adaptation of a best-selling novel so while there is some wiggle room for an adaptation, turning the hero from man airline pilot into an astronaut is probably pushing it too far.

2. re moving to a non-aviation forum, I'm not sure I would find the answers I need, and the ones that have been provided so far. I really came here to answer some technical questions and to get a sense of how real world pilots would deal with the emergencies faced by the pilot in the movie. If I wandered beyond the scope of this forum, I apologize, I will try to keep my queries more technical in nature.

3. re the "could land anywhere" issue, that's why we have them coming into JFK with no fuel. With the highways clogged and no fuel and the airports closed, there aren't a lot of options to choose from. Heading out for open space outside of town is not an option. Any parking lots etc are likely to have planes on them already (our guys were three hours from home when all this came down).

4. re the protagonist putting his faith in God, he doesn't even believe in God and for the majority of the story he thinks the vanishings were only on his plane.

Any thoughts on ways to increase the jeopardy in this situation would really help. They have lost a lot of passengers, they have external damage (sounds like a ruptured fuel tank is the way to go), and they are now low on fuel to try to get home.

Paul

Quoting GST (Reply 16): If you run out of fuel at that height, you can glide for a long time and for a great distance, so the stress levels could be greater in other scenarios.

Great point, and you're right, the "we probably won't reach land" is ugly but hours out it's not exactly "thrilling". So what damage to the outside of the plane would present the "worst case scenario" that would keep the Captain sweating bullets for three hours? I like the idea of losing the engines altogether before landing (they will have a very short landing space and no reverse thrust) for sure.

Thanks!

Paul

Quoting waterdog (Reply 13): and without any real Hollywood names

Correct me if I'm wrong, but isn't Kirk Cameron fairly well known?   

Quoting waterdog (Reply 18): So what damage to the outside of the plane would present the "worst case scenario" that would keep the Captain sweating bullets for three hours?

You could have part of the fuselage ripped open, with some people sucked out and debris from the hole shutting down a couple of the engines.. that happened for real on flight 811, a 747 out of Honolulu. Debris from the damaged leading edge also blew back and damaged the horizontal and vertical tail. You had people vanishing, engine fire, airframe damage, fuel dumping, etc.

Quoting boacvc10 (Reply 15): Moderators, please move this to non-Aviation.

Um, this thread is just fine here, I'm glad it's here. It is definitely 'aviation related' so I can't even imagine your concern.

Quoting waterdog (Reply 18): So what damage to the outside of the plane would present the "worst case scenario" that would keep the Captain sweating bullets for three hours? I like the idea of losing the engines altogether before landing (they will have a very short landing space and no reverse thrust) for sure.

Speaking of "losing engines", perhaps if a single inboard engine was removed in the collision you could have the pilot fighting an out of balance (but probably not impossibly so) aircraft all the way home, combined with managing any other resultant emergencies. Engines are usually designed to separate from the aircraft on their peons before exerting any forces into the wing that might break it, so a collision could conceivably remove one. Even if you kill all other engines before landing the aircraft may have to be making its approach faster than normal to give the pilot enough roll authority to compensate for the lateral center of gravity shift due to losing an engine.

Other things you could play with to make stopping on the runway more difficult is the flaps/slats not deploying or doing so asymmetrically, this would increase the landing speed significantly. Also wheel fires after the emergency braking could give you cause for speedy evacuation and ensuing chaos.

If I were in your position I would steer clear of all the engines stopping turning prior to landing as this is overdone elsewhere, any of the other options to make landing/stopping more difficult are more original and do not need too much explaining to the layperson viewer, perhaps just the pilot making radio calls warning of his intentions. He need not be talking to anyone on the radio to do so, if you cannot get through to someone it is perfectly acceptable to make "blind" calls on the radio just in case someone who needs to know can hear but is for some reason unable/unwilling to respond. This is standard for light aircraft pilots flying into airstrips without air traffic control for example.

Quoting KELPkid (Reply 19): Correct me if I'm wrong, but isn't Kirk Cameron fairly well known?

Absolutely, but on TV and direct to DVD low budget films. Not in Hollywood, and certainly not in theatres. Kirk is a good friend, and a fine actor, but not what investors, studios and theatrical distributors consider a "Hollywood name".

Paul

Quoting HaveBlue (Reply 20): You could have part of the fuselage ripped open, with some people sucked out and debris from the hole shutting down a couple of the engines.. that happened for real on flight 811, a 747 out of Honolulu. Debris from the damaged leading edge also blew back and damaged the horizontal and vertical tail. You had people vanishing, engine fire, airframe damage, fuel dumping, etc.

I watched that episode of MAYDAY again yesterday - now that is scary stuff! Certainly something that could happen when they're approaching New York. Might be expensive to do well, but I'll check with our effects people.

Thanks for the input!

Paul

Quoting waterdog (Reply 18): So what damage to the outside of the plane would present the "worst case scenario" that would keep the Captain sweating bullets for three hours?

Reading your post reminded me of a story I recently read about a Northwest crew who were faced with a rudder malfunction in cruise and had to literally fight the plane (also a 747) all the way to the ground.

http://jalopnik.com/5629528/how-i-saved-a-747-from-crashing

I'd definitely recommend reading through that link; perhaps you could do something similar and have the collision cause damage to a flight control surface or hydraulic system in addition to the fuel tank rupture.

Quoting waterdog (Reply 18): I like the idea of losing the engines altogether before landing (they will have a very short landing space and no reverse thrust) for sure.

As others have said, I feel like this the biggest cliché that could be put into a movie.. just personal opinion, though  

Quoting waterdog (Reply 14): if you were flying this plane and half your passengers vanished into thin air, what explanation might jump into your mind?

That the airline probably won't issue refunds, even under these circumstances.

Quoting waterdog (Reply 17): re the "could land anywhere" issue, that's why we have them coming into JFK with no fuel. With the highways clogged and no fuel and the airports closed, there aren't a lot of options to choose from.

I think you are trying to make the set up too complicated here. Why don't you just make it a west bound flight, so the fuel will already be low when they get to JFK, and have some other circumstance arise where they are unable to divert to use other airports such as disabled aircraft on the runways, national security directive, or something similar. Make the weather lousy and the delays long (perhaps due to missing controllers or other aircraft with greater difficulty) and you will have a pretty realistic situation without having to go through all the hassle of maintaining credibility during a mid air collision, dumping fuel, and hanging a 180 over the North Atlantic.

And please do not make the landing and roll out some 15 minute long drama filled sequence featuring terse, jargon filled remarks from our hero as he wipes his sweat beaded forehead. Its over done.

Quoting GST (Reply 21): perhaps if a single inboard engine was removed in the collision you could have the pilot fighting an out of balance (but probably not impossibly so) aircraft all the way home, combined with managing any other resultant emergencies.

Kalitta already demonstrated this maneuver years ago.

Quoting waterdog (Reply 14): I have watched every episode of MAYDAY and all the YOUTUBE videos I can find and I'm always shocked at how professional the crews seem to remain in the face of unbelievable stress. I

As slamclick (pilot member of these boards) once said: "If I die in an airplane, I expect to die very busy". In an emergency, pilots have stuff to do. They have been trained at length for just such situations. There is little time to worry about dying. You'll often see that pilots really shine when faced with a crisis. Every pilot I know seems to calm down when any situation "heats up". Any average pilot can fly the plane in clear skies. But they aren't selected and trained for that. They are trained to keep cool when the fecal matter impacts the rotary air impeller.

The self-loading cargo, on the other hand, has plenty of time to worry, nothing to do but sit there, and no control or information.

If you want some great info, get the "Air Disaster" books by Macarthur Job. Dozens of major air crashes from the last few decades are described in great detail and in layman's language. Factual (Job used to be an accident investigate) and very very interesting. I bet you'll get plenty of ideas there.

Quoting waterdog (Reply 14): The bottom line is that there is now a serious risk of not reaching land before running out of fuel - so when they finally get back in radio contact, and find out the airports are all shut down, they don't have the option of flying around looking for somewhere else to go. How they run out of fuel doesn't really matter.

What would make me the most nervous in this type of situation is a slow fuel leak...since it would take a while to quantify the leak rate it would be extremely difficult to determine how low your landing fuel would be. The FMC is constantly doing a "Fuel Over Destination" calculation...in the event of a slow leak (or a drag increase, like from damage) that number will slowly drop *for hours* all the way to your destination. If it drops below zero, the FMC is telling you you can't get there from here, but it could take a really long time to get to zero.

If this happened mid-Atlantic with marginal fuel to start with, it might take you 1-2 hours to be sure you couldn't make it. And your radius would be slowly shrinking...for a while you'd make your destination but just be eating your reserves. As more fuel leaks away you'd lose your destination and have to pick a closer alternate...but the fuel to get there would slowly be draining away too. And so on.

If it's a damage-induced leak, it's entirely reasonable that it might change leak rates too. Without knowing where the leak is (very difficult to see usually) you don't know when it will stop either.

Quoting boacvc10 (Reply 15): The plane would be able to land almost anywhere there is a paved surface (roads, highways, small airports, large airports, fairly smoothly with a risk of running off the end of the runway) and in a pinch, also land on water, with obviously catastrophic results - but at least they are down on the ground, to the best of their ability.

Just have them land at night...that makes finding non-runway landing surfaces much more difficult.

Quoting waterdog (Reply 18): So what damage to the outside of the plane would present the "worst case scenario" that would keep the Captain sweating bullets for three hours?

Fuel leak + a fuselage hole. The fuselage hole causes you to lose pressurization, so you have to complete the flight at 10,000'. That means you're at the mercy of all the weather between you and your destination.

The simplest option might be to have the collision be relatively minor (the wingtip of the other aircraft smacks the forward fuselage) but it sheds enough FOD to cause one of the engines to suffer a rotor burst. The shrapnel pierces a fuel tank and fuselage. That leads to a slow leak (indeterminate range) and loss of pressurization (forces them down into the weather). That's a situation that would be nerve-wracking and suck for hours. You can even have the chunk that went through the fuselage injure a passenger just so you can pile a medical emergency on top of it all.

Tom.

[Edited 2011-08-18 21:59:28]

Quoting tdscanuck (Reply 27): The simplest option might be to have the collision be relatively minor (the wingtip of the other aircraft smacks the forward fuselage) but it sheds enough FOD to cause one of the engines to suffer a rotor burst. The shrapnel pierces a fuel tank and fuselage. That leads to a slow leak (indeterminate range) and loss of pressurization (forces them down into the weather). That's a situation that would be nerve-wracking and suck for hours. You can even have the chunk that went through the fuselage injure a passenger just so you can pile a medical emergency on top of it all.

Whilst I agree that this is an excellently dramatic scenario, you're just not going to get it on a JFK-LHR route where runways are reasonably near and the Captain would certainly go to the nearest, especially if out of radio contact and knows no better. If it is essential that the divert takes 2-3 hours, would it critically damage the story if the route changed such that they are over an ocean still but much farther away from a runway? Either that or the pilot needs to somehow be told that all nearer airports are unusable for whatever reason, tricky if the story requires a radio black-out.

Quoting GST (Reply 28): you're just not going to get it on a JFK-LHR route where runways are reasonably near and the Captain would certainly go to the nearest, especially if out of radio contact and knows no better

Agreed. We have ETP alternates just for this reason. 3 1/2 hours out we are probably pretty close to the ETP, depending on the winds. The depressurization scenerio can be very demanding on fuel, often arriving at the ETP alternates with little fuel. Gander and Shannon are common ones to use, as are St. John and Prestwick. But if you have an engine out, loss of pressurization, and have a medically critical passenger, no one is going to slog the extra hours back to JFK, past Gander, Halifax, and other suitable airports, even if they have the fuel.

Quoting lowrider (Reply 29): But if you have an engine out, loss of pressurization, and have a medically critical passenger, no one is going to slog the extra hours back to JFK, past Gander, Halifax, and other suitable airports, even if they have the fuel.

I struggled with this too...does it have to be JFK? If you're running LAX-SYD and have this kind of event happen, the ETP between LAX and HNL is probably at least 2 hours out and then all you need is bad weather over Hawaii to be forced into a 2-3 hour divert.

HOU-AKL is even worse from an ETP standpoint...

Tom.

Quoting tdscanuck (Reply 30): does it have to be JFK?

Thats why, if you make it a west bound flight, you can have any number of things happen past the ETP where the crew will decide to press on, and you can easily run into a fuel situation as a result. It could be a few relatively simple issue, such as an IDG that goes bad and won't disconnect, resulting in an engine shutdown. Adverse winds and a lower cruise altitude cause them to get a little behind on fuel. Add some external pressure to continue to JFK, a combination of the disappearances and some VIP pax, for example, and you have a more believable situation. It also won't be so dependent on special effects and gimmicks drive the story.

If it doesn't have to be JFK, the LAX-NRT would be sufficiently long and at about 3 1/2 hours out, should be sufficiently distant from any alternates to make the return to LAX plausible.

Thanks again for all the input! This is indeed very helpful.
The most important thing in this whole part of the movie is to keep the protagonist (pilot) ACTIVE and not just REACTIVE. He has to make tough decisions and implement them, not just struggle to keep things on track. That's why the FUEL DUMP was there in the first place. He had to choose between risking a fire and not having enough fuel to get back to JFK.

Any quick ideas for:

THIS happened so I could either do THIS or THAT. If I pick the wrong one it could have catastrophic consequences.

Looking through the notes on destination, MAKING THE DECISION to go to JFK instead of Gander is one such decision. He'll need a good reason, but at least he's taking matters into his own hands.

Quoting Starlionblue (Reply 26): And please do not make the landing and roll out some 15 minute long drama filled sequence featuring terse, jargon filled remarks from our hero as he wipes his sweat beaded forehead. Its over done.

Aw man, now I have to delete 15 pages! Regarding the jargon, that's another situation I face mid-flight. He has not radio contact and no co-pilot, so the technical jargon will mean nothing to anyone. We had toyed with having him talking to cockpit voice recorder so there would be a record of what's going on, but that felt really awkward. So he has to explain to the guy who comes in to help him, exactly what's going on as he instructs him to do things. No, there's no other pilots on board. Remember, almost all pilots go to heaven!

Speaking as a pilot, and a former commercial airline pilot, the scariest thing that can happen is an onboard fire, especially if the fire is in an area that is inaccessible.

So with that in mind, how about a fire in the forward cargo hold? The extinguishers (Halon, in case you want to know) are initially able to cope with the fire, settling things down, skipper takes a breather. But then the fire flares up again (you'll have to figure out a reason why that happened yourself), and having depleted the extinguishers the captain has to decide what to do about it. I'm thinking dispatching a cabin crew member downstairs, through the access hatch (that you may have to invent - not that familiar with the B747) on the main-deck, to fight the fire. That should keep the blood pressure up for a a good 30 minutes or so.

Your inflight collision that led to the loss of fuel could also have damaged other systems, in this case the hydraulics would be the more "interesting" choice. Failed hydraulics can lead to all sorts of nastiness, ranging from inability to lower the gear (having to resort to hand-cranking it down) and flaps (resulting in a high landing speed) to total loss of all moveable surfaces (aileron, rudder, elevator etc.). Should the latter happen, you'll have to make your Captain fly the aeroplane using throttles only, which can either go very wrong (loss of all lives onboard following a crash), partially wrong (UA232) or end in a roaring success (OO-DLL in SDA).

Quoting waterdog (Reply 32): THIS happened so I could either do THIS or THAT. If I pick the wrong one it could have catastrophic consequences.

That could be a lot of situations. For example, if the flight heads to JFK there will be a point where they are committed to JFK or something similar, as they will no longer have enough fuel to turn around and head to Gander, or Halifax. In order to give up a known, good option, in such an abnormal situation, you are going to have to create some imperative to do so. A large, dramatic situation like a fire that can't be extinguished is going to drive the crew to land at the nearest suitable, regardless of other considerations. You need something that is ambiguous, and only mildly serious, I think your loss of comm creates that. Do I land at a relatively quiet out of the way airport that is nearby, and is less likely to be saturated with traffic, but may create problems with immigration, security and we may be delayed there for an indefinite amount of time, or do I continue on blindly into some of the most congested airspace in the world, with no definite idea of what I will find for weather or available facilities, knowing that I may not have enough fuel to reach a better option. If this takes place in the winter, having the runway plowed and providing shelter for the pax after landing is also a problem for the Canadian options.

If you really want an aircraft malfunction make whatever knocks out communications, also wipe out GPS coverage, or create some other navigational trouble. This will force them to use shorter range navaids, and take less direct routes and would generally create stress in a cockpit where all the workload is already being piled on 1 person.

The set up you gave us leaves several other issues:
1. The loss of communications: Typically if this happens, a flight will continue on with its last clearance. Also, do you lose all comms, HF only (long range), Satcom, or simply contact with ATC? Crossing the North Atlantic, pilots will talk with each other, passing info on weather, turbulence, and may even relay info for each other if one flight temporarily loses contact with the controlling agency. If I was still in contact with other aircraft, I would try to coordinate my actions with other aircraft, and also try to get information from those ahead of me.
2. The loss of so many people would create considerable stress and uproar. How does that get dealt with, particularly if some of the flight attendants are gone, too?

Quoting waterdog (Reply 32): Aw man, now I have to delete 15 pages!

Sorry, but I was thinking more Hitchcock, less Bay.

Quoting waterdog (Reply 32): He has not radio contact and no co-pilot, so the technical jargon will mean nothing to anyone. We had toyed with having him talking to cockpit voice recorder so there would be a record of what's going on, but that felt really awkward.

Might come across as filler. If you retain air to air comms, you could have him talking to other pilots about what happened on the various aircraft, and theories as to why. Also, he will have to talk to the flight attendants, and may elect to have one help with cockpit workload. In the heat of an emergency, few if any pilots are going to take the time to give extensive technical instruction. It will be more along the lines of, "watch this and let me know if X happens", or "listen to this frequency with these headsets and let me know if you hear Y".

Quoting waterdog (Reply 32): Remember, almost all pilots go to heaven!

There is the old joke about the difference between God and pilots. God doesn't think He is a pilot.

Quoting B777LRF (Reply 33): ranging from inability to lower the gear (having to resort to hand-cranking it down

No hand cranking on the 747. If it won't free fall, you land without it. If you get partial gear, then you land with what you get.

Quoting B777LRF (Reply 33): and flaps (resulting in a high landing speed) to total loss of all moveable surfaces (aileron, rudder, elevator etc.).

You would have to lose at least 3 hydraulic systems on the 747 to significantly impact your flight controls. There are also electrical back ups for the flaps. To lose all the primary flight controls via hydraulic failure, you have to lose all the hydraulics, which means either 4 leaks, and/or 8 pumps lost. If that is the case, then it is just your day to meet your maker. Not impossible, just so unlikely that as to be nearly so.

[Edited 2011-08-19 10:59:04]

Here's a suggestion - maybe scrap the 747, make it a 777, then a single engine failure is more exciting. If you have the airplane completely running out of fuel, then you can have things going on like deploying the RAT, emergency gear extension etc. Read about the 'gimli glider', and watch 'Falling from the Sky: Flight 174'.

Another fun scenario would be perhaps if both engines fail inexplicably, and the RAT fails, then you could have the crew using the in-flight APU capability for backup power. Just using my imagination  

Quoting Wingscrubber (Reply 36): Here's a suggestion - maybe scrap the 747, make it a 777, then a single engine failure is more exciting.

If it happens hours from touchdown, how do you get the captain to justify bypassing St. John, Gander, Halifax, Bangor, Manchester, Boston, Steward, and countless other airports to keep driving on to JFK? For something like that to work it would have to be something like LAX-HNL, where there are no diversions between.

Quoting waterdog (Reply 32): So he has to explain to the guy who comes in to help him, exactly what's going on as he instructs him to do things.

Do you already have in mind a character to join the captain? I know one ex cabin crew member for a major airline who as a recreational glider pilot and holder of a radio license was on occasion called on to monitor the radios unattended when one pilot was on rest break and the other needed to relieve themselves. By having some conveniently semi-qualified crew member or passenger you can still have a semi-jargony cockpit dialogue, leaving room for explanation where required for the story also.

Quoting Wingscrubber (Reply 36): you can have things going on like deploying the RAT

In case you are unaware, the RAT (Ram Air Turbine) is a small windmill that folds out into the airflow to generate electricity to work the essential electrical and hydraulic systems in the event of all engines failing. Normally there are electricity generators in the engines to supply the power.

Quoting lowrider (Reply 37): If it happens hours from touchdown, how do you get the captain to justify bypassing St. John, Gander, Halifax, Bangor, Manchester, Boston, Steward, and countless other airports to keep driving on to JFK? For something like that to work it would have to be something like LAX-HNL, where there are no diversions between.

   I second that.
Does it really have to be JFK? Or could you just shift the story to Los Angeles or San Francisco? If the flight would be a transpacific, alternate airports are much rarer than on a transatlantic flight. Over the pacific, you can easily find places 2 or even 3 hours away from a suitable airport. Possible routes could be LAX/SFO - SYD/MEL or even HNL as already mentioned. That way you would avoid to construct a (possibly) unrealistic reason to avoid all the alternates...
You could also make the plane be an Airbus A380, as it is the latest widebody (twin aisle) commercial plane in service (soon to be replaced by the Boeing 787, the 747s are getting old and start to be withdrawn from passenger service) and the the largest passenger plane ever built - if that is of any importance for the story.

Quoting waterdog (Reply 14): d I'm always shocked at how professional the crews seem to remain in the face of unbelievable stress.

I have recently read 'War' by Sebastian Junger and 'Riding Rockets' by Astronaut Mike Mullane. Both say something along the line that if there's a *serious* threat to your life, you act mechanically like a robot and without any fear. It is when the threat is gone and you have time to contemplate that your knees start trembling.
Perhaps your pilot should not be too busy but have a little time to come to grips with the situation.

If I were a pilot, I'd start panicking if there's something I cannot explain. Something that the 3,000-page(?) handbook doesn't mention - such as the sudden disapperance of my co-pilot ... "Three more hours to go, eh, Steve .... Steve? Steeeve?" "There's 3,000 pages of instructions for all kind of procedures, accidents and what not, but nowhere it is said what I am supposed to do if my co-pilot disappears."

By the way: On long haul flights there's always more than one crew aboard.

Quoting tdscanuck (Reply 27): Fuel leak + a fuselage hole. The fuselage hole causes you to lose pressurization, so you have to complete the flight at 10,000'. That means you're at the mercy of all the weather between you and your destination.

Plus you'd have a higher fuel burn of course.

Quoting waterdog (Reply 32): THIS happened so I could either do THIS or THAT. If I pick the wrong one it could have catastrophic consequences.

Well, if he has no radio contact, he could realize that the runway is not cleared and go around very late. And if then a small aircraft, such as a Cessna 172, which pilot has been disapppeared as well, flies right into his jumbo ... that would basically be a double-shocker on short final.
This would be a tricky situation in which he needs to act very quickly: He has little power, one engine is burning, and he has no place to land.
He could try landing on a highway - or actually he could not as those are crowded, if I get you right
He would have the option to try flying into another airport - but what if the runway there isn't cleared as well?
He could try a landing on the Hudson river (as it has happened before with a smaller Airbus A320)
or try landing on an open field.

I have no idea how much I divert from the original book -probably very much. At least this would not be too technical. When you asked us for a problem:

Quoting waterdog (Reply 32): THIS happened so I could either do THIS or THAT.

... changes are that things will get pretty technical, and you'd have your pilot explain to a flight attendant that the "green pressure line that .... blah blah blah" went boink. But I doubt he would actually bother explaining anything to her while fighting for his jet.

[Edited 2011-08-20 15:05:50]

Quoting waterdog (Reply 32): THIS happened so I could either do THIS or THAT. If I pick the wrong one it could have catastrophic consequences.

That reminds me of the fatal accident (I think South African?) were the cabin was faced with too much smoke, and the crew ultimately decided to open doors after decreasing altitude. However apparently, due to increased oxygen flow, the fire actually spreaded much quicker, so THAT was the WRONG decision.

I will throw in some more ideas, maybe some of them will ignite a good idea for yourself:
- About radio loss: How about the radio antenna is damaged after the collision? They could try use the mobile phone once they crossed the atlantic and reduced altitude, or send somebody repairing the antenna, or find some passenger aviation geek travelling with a scanner, so they can at least listen.
Being able to listen, but not be heard can produce scary scenarios too.

- How about multiple events, like fix one thing, another problem pops up, fix it again sacrificing something, and due to that, another problem arises. This is useful for keeping tension over a longer time. Once the viewer is reliefed, a new "ooh ooh!" comes up.

- The collision could produce an immediate problem, and a sleeping one which occurs later on. (Some wires severed, which produce a short circuit only after some turbulences, or the slowly leaking fuel someone already suggested)

- How about a "symptoms but unknown cause" approach: You have fires popping up every now and when, here and there, and manage to put them out, but you dont know, what is actually causing them. So the viewer (and pilots!) are frightened throughout the hole time.
I would be much thrilled in a movie, where I do not know the causes (like the unknown killer in a thriller) until the end, rather than being faced with a known but hard problem.
I am just thinking what the "cause" could be... A rat biting one wire after another is a bit boring  

- The collision ruptured some water/wastewater system, leaking water, which disables system slowly one by one, leaving them out in the end with no electronics. OR: It starts fires, which are put out, and they shut off or cut certain generators (is that possible?) to prevent more short circuits + fires. They glide in with no (or minimal) electric support, but face the big decision, wether to reconnect the various generators to produce electricity for "the last mile", possibly igniting a new big fire.
Now this is a wild guess of mine and requires someone to confirm, if its even remotely possible  

Lastly, I would like to say, it is a very interesting thread. Usually, we all discuss about how we can make aviation more and more safe, and now we are all discussing about how the damn hell we can bring that plane down  

Another possibility for delayed damage could be the collision damaging but not piercing the fuselage pressure barrel, so at some later point in time you can have it finally give way and necessitate an emergency descent with damaged aircraft.

Also consider the cabin air supply as a fun thing to play with, the air is bled out of the engine compressor (before the air gets to the combustion chamber so it is still clean), and piped to the cabin. You could have the collision damage the bleed air lines and be feeding fumes into the cabin.

Quoting hal9213 (Reply 41): Usually, we all discuss about how we can make aviation more and more safe, and now we are all discussing about how the damn hell we can bring that plane down

Well, its more like trying to figure out how we can nearly bring the plane down.

Just a few nightmare scenarios off the top of my head:
G3 1907 - Midair collision
AC 797/SA 295/J7 592/SR 111/5X 6 - Inflight fire
TS 236 - Out of fuel over Atlantic
UA 232/JL 123/DHL OO-DHL - Total loss of hydraulics
AQ 243/UA 811/AA 587 - Structural failure
CI 006 - Loss of control
KE 007/KE 902/IR 655/S7 1812 - Downed due to military action
FX 705 - Attack by disgruntled employee

All of the above offer quite a few elements for your movie.

[Edited 2011-08-25 22:21:31]

[Edited 2011-08-25 22:23:40]

Just want to say thanks again for all of your help here. This is going to be a much better script as a result. However, the big changes (lose the fuel dump and add in some of the other suggestions here) will take a bit of time, and right now I have to get another draft out by the end of the day. Sooooo, I have to make what I've got work better.

In the flight deck, after the flight attendant reports the engine sparking - the captain decides he has no choice but to dump some fuel to avoid a fire. She has to sit in the co-pilot's seat and follow his instructions as the implement the procedure.
Right now, it's too much of a "push that big button" thing. I'm hoping someone can take a look at the little scene below and tell me what the stupid stuff is.

INT. FLIGHT DECK - NIGHT
Hattie stares at the fuel gauge, terror in her eyes.

RAY
We can do this. I’m going to start a climb. We’ll keep the fuel stream below the wing, away from that engine. Those two switches on the side there... you’re going to throw those when I give the word.

Hattie nods. Ray pulls back on the yoke. Or at least he tries. Instead of climbing, the plane just lists to one side.

RAY (CONT’D)
We lost the flaps.

HATTIE
What do you mean?

RAY
We can’t climb. Looks like we’ve started our decent into New York... three hours early. I’ll need to descend at least a thousand feet to keep the fuel stream clear but we can’t waste a second. Every foot we drop is a foot closer to the water.

He engages the intercom.

RAY (CONT’D)
Folks, this is your captain. I need everyone in their seats with seat belts fastened. Immediately. I’m going to have to dump some of the fuel from the wing on the right side of the plane. This is a routine procedure and you may see some spray. Please don’t panic, it won’t last long and it’s something I have to do to ensure the safety of the plane.
He takes a deep breath.

RAY (CONT’D)
You ready?

HATTIE
Ready.

He checks his instruments, starts a steep descent.

RAY
Now.

Hattie throws the switches.

I couldn't comment on the cockpit procedures and dialogue, but here are some points:

First of all, it is elevators (on the small wing at the tail) and thrust from the engines that control the attitude of the aircraft and change its altitude. If you have a dodgy engine scenario and have one (or more) shut down, the aircraft may find it difficult to climb for that reason, especially if you are already quite high, this could be a quick change to make. If you are very high it could force you to descend as you require for the story. Perhaps your pilot may be worrying about having to descend at least a thousand feet until there is thick enough air for the remaining engine(s) to maintain altitude (this depends very much on the plane being extremely high to start with if only one engine is at fault)


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Photo © Alasdair Mulhern


That is a 747-400 dumping fuel, as you can see it happens well clear of most of the aircraft, and vapourises more or less instantaneously when it hits the airstream, so no need to worry about separating it from the aircraft. Even if the plume catches fire it isn't such a problem as the flame front can only travel about 10mph when the aircraft it traveling many orders of magnitudes faster and any flames will be in the wake faster than you can startle a passenger. If you need to worry about the fuel stream catching fire, invent an electrical fault near the dumping vent at the wingtip, for example on the strobe lights or aileron actuators.

[Edited 2011-08-26 15:51:59]

Quoting hal9213 (Reply 41): It starts fires, which are put out, and they shut off or cut certain generators (is that possible?) to prevent more short circuits fires.

It is possible to shut off individual generators but, with the normal way that modern airplane electrical systems work, the buses will reconfigure to remain powered. You can isolate a bus, which shuts down everything on that bus, but that's not normal procedure.

Quoting waterdog (Reply 44): In the flight deck, after the flight attendant reports the engine sparking - the captain decides he has no choice but to dump some fuel to avoid a fire.

Engines don't really "spark", and dumping fuel won't avoid a fire (by itself). What you're talking about is a fuel tank leak where the fuel leak is getting near the engine and may ignite (or feed an already present fire). Aircraft have very stringent flammable fuel leakage requirements to prevent exactly this scenario.

Quoting waterdog (Reply 44): RAY We can do this. I’m going to start a climb. We’ll keep the fuel stream below the wing, away from that engine

Again, you need some other damage (fuel leak, or damage to the dump system) to enable this. A great deal of design work goes into making sure that the fuel dump plume never gets near anything that could ignite it. It doesn't go anywhere near the engine normally.

Quoting waterdog (Reply 44): Hattie nods. Ray pulls back on the yoke. Or at least he tries. Instead of climbing, the plane just lists to one side. RAY (CONT’D) We lost the flaps.

Wrong terminology...flaps aren't used at cruise and have nothing to do with pitching up or down. I would switch this to "We've got flight control damage."

Quoting waterdog (Reply 44): RAY We can’t climb. Looks like we’ve started our decent into New York... three hours early. I’ll need to descend at least a thousand feet to keep the fuel stream clear but we can’t waste a second.

Drop the specific altitude...given the uncertainty in your scenario, the pilot would have no idea how far he'd have to descend. If you scratch off "at least a thousand feet" the line still works.

Quoting waterdog (Reply 44): his is a routine procedure and you may see some spray. Please don’t panic, it won’t last long

Fuel dump is actually relatively slow, especially if you're trying to empty an entire tank like your scenario suggests...perhaps 30 minutes or more.

Tom.

Quoting waterdog (Reply 44): In the flight deck, after the flight attendant reports the engine sparking - the captain decides he has no choice but to dump some fuel to avoid a fire. She has to sit in the co-pilot's seat and follow his instructions as the implement the procedure.

Setting aside for a moment why an engine would spark, the first thing you would do is secure the engine, which would involve shutting down fuel, pneumatic, hydraulic, and electrical systems affiliated with that engine. This would necessitate a descent to a known, 3 engine drift down altitude. The fuel dump on a 747-400 is relatively simple, involving maybe a half dozen or eight switches in the middle of the overhead panel. After selecting the amount to to remain after dumping the process is relatively automatic. Of course with 3 hours flying time left, you want to make sure you leave yourself enough fuel for contingencies. Typically you would wait until you are fairly close to your destination before dumping.

Do with the input what you will.

Quoting waterdog (Reply 44): the plane just lists to one side.

At the risk of being pedantic, and though ocean going vessels and aeronautical vessels share a lot in common, you would never say 'listing' for an aircrafts tilt, it would be 'banking'. Unless the aircraft was in the water. The plane has an uncommanded roll or bank to one side is more appropriate.

I'm having a very hard time with this dumping fuel scenario for several reasons.
- Sparks from an engine are no reason to dump fuel.
- Three hours to an airport, you really don't want to dump fuel. What if you need to go to an alternate? I would think if you are unsure of the status of the outside world (e.g. The Langoliers) you really want to keep all your fuel AND go for the most efficient cruise speed/altitude distance-wise.
- Fuel dumping is done to decrease weight, not to avoid a fire. I don't recall an incident where a burning engine on a jet airliner in flight has set fuel alight, ever. Correct me if I'm wrong.

Quoting waterdog (Reply 44): Hattie stares at the fuel gauge, terror in her eyes.

Is there really just one fuel gauge? A 747 must have half a dozen tanks at least. So you'd have several gauges, right. Also AFAIK it isn't that simple. Even on a modern airliner, calculating remaining fuel and how far it will get you manually is not trivial. Different altitudes, winds and weight give very different consumption. It's not like a car where fuel consumption is within a rather narrow band and you can make a good guess by mentally extrapolating.

Quoting waterdog (Reply 44): Folks, this is your captain. I need everyone in their seats with seat belts fastened. Immediately. I’m going to have to dump some of the fuel from the wing on the right side of the plane. This is a routine procedure and you may see some spray. Please don’t panic, it won’t last long and it’s something I have to do to ensure the safety of the plane. He takes a deep breath.

This doesn't sound like an airliner pilot at all. If you look at the transcripts of many, if not most, emergencies, you will notice how pilots sound calm, speaking very deliberately. If he had to address pax at this stage, the Captain would use much more soothing verbiage than "don't panic". That just sounds as if there is a reason to panic. Heck, I would think he has better things to do than address the pax at this stage! If they really need to get back in their seats, he would turn the seat belt sign on and tersely ask flight attendants to return to their seats. The F/As would then per procedure make an announcement asking pax to strap in.

A classic example is Captain Moody of BA flight 9:
Ladies and gentlemen, this is your captain speaking. We have a small problem. All four engines have stopped. We are doing our damnedest to get them going again. I trust you are not in too much distress.

[Edited 2011-08-26 23:33:54]

[Edited 2011-08-26 23:34:17]

[Edited 2011-08-26 23:35:13]