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water landing

water landing
 
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Ok iv got some ideas mostly to do with aviation I havent read to much on this site so apollogies if i repeat any ideas.

Retro fitting existing airliners with water landing capabilitys... in an emergancy the captain dumps the fuel then pulls the big red lever. this causes a series of explotions to detonate, on the 4 engine pylons, thus jetisoning the jets, we now have the ability to glide further and skid on the surface of calm water

couple this with some slow down parachutes in the tail section (like on the space shuttle) to take the plane from 160 mph down to 30/40 mph and you've got a pretty survivable gear up crash landing even in quite choppy water

EkranoMan, Sep 04 2014

US Airways Flight 1549 http://en.wikipedia...Airways_Flight_1549
A pilot with skills beyond outstanding ... [8th of 7, Sep 04 2014]

Problems with Pins http://community.se...921227&slug=1532256
Breakaways already installed; not completely problem free [lurch, Sep 04 2014]

737 engine http://en.wikipedia...ral_characteristics
weight [EkranoMan, Sep 05 2014]

ditching of flight 961 http://en.wikipedia...Airlines_Flight_961
Ethiopian_Airlines_Flight_961 ditching hard [EkranoMan, Sep 05 2014]

[link]






       // Retro fitting existing airliners //   

       It's extremely difficult to retrofit any substantial modification to an existing civil airframe.   

       // jetisoning the jets, //   

       If you detach the powerplants, you'll completely throw the weight and balance of the airframe. Civil arcraft are designed to have a centre of gravity pretty much co-located with the wing mainspar. Change that, and you put huge - possibly unmanageable - loads on the control surfaces.   

       // we now have the ability to glide further //   

       The drag would be reduced, as would the weight; for a given altitude, the glideslope could be extended somewhat.   

       // and skid on the surface of calm water //   

       With a "smooth" underside - without dependant engine nacelles, or landing gear - the chances of a smoother belly landing are improved. However, see <link>.   

       // couple this with some slow down parachutes in the tail section (like on the space shuttle) to take the plane from 160 mph down to 30/40 mph //   

       It is easy to shed airspeed with judicious use of flaps, speed brakes, and attitude. Civil transport aircraft wings will stall at 120 knots. The aircraft would then nosedive into the water.   

       Ditching calls for maintaining flying speed just above stalling, in a nose-up attitude, until contact is made, then relying on fluid drag to decelerate to a stop.   

       // and you've got a pretty survivable gear up crash landing even in quite choppy water //   

       Debatable.   

       Welcome to the HalfBakery ! Aviation ideas are always welcome, and a popular topic of highly informed debate.
8th of 7, Sep 04 2014
  

       Welcome, [EkranoMan]! Not sure this would be such a great idea, though. I suspect that a good pilot in control of a normal passenger aircraft could make a water landing without losing the engines. As [8th] pointed out, you can't slow the plane down much below 100mph, or the thing will stall.   

       A safer option, as used by MH370 when faced with a disaster over the ocean, is simply to vanish completely.
MaxwellBuchanan, Sep 04 2014
  

       Civil airliners will likely go to over-the-wing engine designs for reasons of noise abatement. The absence of under wing scoops should make for more ditch-able aircraft.
bs0u0155, Sep 04 2014
  

       Wings, schmings, lose the things. Leave say a 10 foot section on each side. With any luck you're right-side up with your ass dragging in the water when this happens, then only having to worry about skipping over the pond at 100mph.   

       I think the parachutes should go on top of the aircraft, given its nose-up orientation when landing. Put them on the hind end and they'll either break when they catch the water, or pull the tail off.   

       Welcome to the HB. When you finish a post, it's a good idea to check it over for spelling mistakes and grammar and other shit either before you hit <OK> or even afterwards when you see it on the page for the world to read.
FlyingToaster, Sep 04 2014
  

       Every once in a while you hear of the emergency slides inflating inadvertently on a passenger aircraft. That's kind of expensive - a few tens of thousands of dollars to replace.   

       The same kind of scenario with the engine jettison pyrotechnics would be much more expensive.   

       Plus - I'll bet you'd kiss ETOPS good-bye.
lurch, Sep 04 2014
  

       Engines are attached to the pylons, and the pylons to the wings, with fracture bolts - intended to fail under overload before any other component does.   

       Incorporating pyrotechnic cutters would not in fact be that difficult or expensive, it's a mature technology.   

       If a plane is ditching, the engines will be BER anway, especially in seawater. Dropping them just at touchdown makes sense. Dropping them at altitude does not.   

       ETOPS certification would be … challenging.
8th of 7, Sep 04 2014
  

       >you can't slow the plane down much below 100mph, or the thing will stall.   

       Ground effect?   

       The logical solution is just plate the bottom of the plane with sodium. The steam forms a cushion allowing the plane to well, plane across the water, giving more time to decelerate. Coupled with small submarine clamped to the bottom of club class this should save the lives of the ones with expensive lawyers.
not_morrison_rm, Sep 04 2014
  

       yes retro fitting a parachute system would be a monumental upgrade, i almost wasnt gonna surgest it, but this is halfbakery. got to have radical ideas here.   

       i dont think adjusting the pylons would be that difficult though. if they where to make the changes to the engines before a routine refit. The cost isnt so much the price of the parts, its the cost of the loss of revenue that the aircraft would have made if it wasnt in the hanger.   

       the 737 engines weigh 1.5 to 2.1 metric tonnes (link) dropping that amount in level flight would definitly result in atleast a big bump.... but (if I remember correctly) there is a tactic that glider pilots use... that is to fill the craft with a half ton of water ballast. nose down, build up lots of speed, then drop ballast and then glide up to much higher than there original altitude. if the pilot of the 737 were to nose down while dropping the engines, there would be significantly less up pressure on the wings, meaning much less of a bump.   

       i dissagree that the craft would become unstable because the engines are located on the wings, the wings are at the centre of gravity in most civil aircraft, thats why they store most of the fuel in the wings.   

       dont get me wrong, I dont think it will be anything less than a brutal crash land. but when you see Ethiopian Airlines Flight 961 ditch see link. you would think how did 50 out of 175 people manage to survive. plus many would have survived the impact and drowned soon after   

       // and you've got a pretty survivable gear up crash landing even in quite choppy water //   

       Debatable.//   

       indeed :)   

       // I suspect that a good pilot in control of a normal passenger aircraft could make a water landing without losing the engines. // I think it would be easier without the engines. when you ditch a plane its a complete right off, the engines would become scrap anyway, so why keep em.   

       //A safer option, as used by MH370 when faced with a disaster over the ocean, is simply to vanish completely.// lol mean ;)   

       // Civil airliners will likely go to over-the-wing engine designs for reasons of noise abatement. The absence of under wing scoops should make for more ditch-able aircraft. — bs0u0155//   

       its a big industry, and it dont look like its changing its designs much for a very long time. plus theres trillions of dollars worth of planes in the sky already seee (link) the system for maintaning/swapping engines is set up for under wing. the're not going to care that much about the few ditchings per decade, the designers will just moraly shift the blame to the poor mantainance of the carriers. this idea isn't a game changer, its just a quick patch job.   

         

       //I think the parachutes should go on top of the aircraft, given its nose-up orientation when landing. Put them on the hind end and they'll either break when they catch the water, or pull the tail off. FlyingToaster, Sep 04 2014// yes that is a better place to put them in this situation. keeps the nose up for as long as possable. but i was thinking that rear chutes would be very useful in emergency conventional landings. but the way they do things, any type of chute would never be cost effective.   

         

       // Every once in a while you hear of the emergency slides inflating inadvertently on a passenger aircraft. That's kind of expensive - a few tens of thousands of dollars to replace.   

       The same kind of scenario with the engine jettison pyrotechnics would be much more expensive. — lurch, Sep 04 2014 //   

       emergency slides are connected to the doors which are opened twice per flight. this system would sit quietly in the background with plenty more failsafes.   

       // Breakaways already installed; not completely problem free— lurch, Sep 04 2014 // those are uncontrolled Breakaways. with my system the captain could make the choice of the type of emergency that would require a fast jettison thus you would have the ability to make solid pins that would never have the problems that are in that artical.   

       // Ground effect?   

       The logical solution is just plate the bottom of the plane with sodium. The steam forms a cushion allowing the plane to well, plane across the water, giving more time to decelerate. Coupled with small submarine clamped to the bottom of club class this should save the lives of the ones with expensive lawyers. — not_morrison_rm, Sep 04 2014 //   

       you can tell from my name i love ground effect.   

       also ETOPS? i would of thought that this would give the plane a dramaticaly increased glide slope. when an engine fails it goes from being a thrust device to a great big air brake, if the captain jettisons a failed engine the remaining engine would take you a lot lot further. or am i missing something?   

       ps thanks for the welcome everybody thumbs up.
EkranoMan, Sep 05 2014
  

       //Am I missing something ?//
  

       About //1.5 to 2.1 metric tonnes// halfway out on one wing. My sliderule's in the shop: I suppose ailerons could compensate.
FlyingToaster, Sep 05 2014
  

       large aircrafts often have a 5th pilon port on one side so they can transport an engine that needs repair from one country to the home base. you can easy trim the craft by pumping some of the 20 tons of fuel from one wing tank to the other( or just drop fuel from one side )
EkranoMan, Sep 05 2014
  

       You could mount drag devices on the wingtips. Passenger safety notwithstanding, those engines are like $5-10mil each.
FlyingToaster, Sep 05 2014
  

       the less drag, the higher the etops the higher the etops, the further into nomansland you can travel the further into nomansland, the more of a direct route you can take, which means more fuel savings and quicker journeys   

       lets say we have 200 passengers each paying $500 thats $100000. then lets say that profit is then half of that. so after 200 flights without a failed engine, they can afford a new one. also, a failed engine, is not worth as much as a new engine. $5-10mil may sound like a lot to you and me, but say these guys are running >300 flights a year, per plane. Besides, the most important thing here, is that you would only drop an engine if it failed in ETOPS nomansland, which is probabily <5% of the journey + i think most engines fail soon(ish) after takeoff.
EkranoMan, Sep 05 2014
  

       Drag has very nearly zilch squat to do with ETOPS. All current airliners are built to handle quite adequately with an engine out - the thing that effects the granting of ETOPS is the probability that you'd lose a second engine while flying with one out. You have to keep your IFSD (in- flight shutdown) rate down to around 0.01 occurrences per 1000 flight hours to maintain a 180/207 minute rating. That's around one in every 100,000 flight hours.   

       So, with a current average of about 40,000 long haul blocks per day, averaged at about a 5 hour stage length, we'd see about 2 IFSDs a day - if everybody was running top-notch maintenance - which they're not. It's kind of hard to get really good numbers, but I'd guess a real figure would be upwards of 4.   

       Rolls Royce, GE, & Pratt&Whitney combined couldn't keep up with you tossing that many engines in the drink. By the middle of the second week you'd be setting up power-by- the-hour contracts with Tumansky.   

       Oh, and nobody makes a 50% profit margin on flying airplanes around. Nobody even makes 10% - unless you're running drugs, or flying charters for the US Government. Or running drug charters for the US Government.
lurch, Sep 06 2014
  

       What [lurch] said.   

       // a failed engine, is not worth as much as a new engine //   

       Quite untrue. An engine may shut down with a very minor fault, to pre- empt further damage occuring. Repair may be accomplished without removal of the unit from the airframe.   

       Consider an oil pressure failure; the system shuts down N1 before any actual damage occurs. A new oil seal/pipe/pump and a refill of oil and all is well again. It's just that you just can't do that in flight.   

       Even a turbofan that's ingested a flock of geese and abruptly stopped may still be repairable, or if not there may be a high proportion of undamaged components that can be recovered, recertified and re- used.   

       And when planning a route, shortest often doesn't equal best. Winds aloft are critical. Tracking round a weather system to turn a ten knot headwind into a ten knot tailwind is well worthwhile, and at FL300 and above 100-knot winds aren't uncommon. That can be 20% of your IAS in some circumstances. And since almost all transcontinental routes are a Great Circle, or a sector of one, effectively you always have two choices.   

       Get yourself a globe*, a couple of pins, and a length of string. Stick the pins in a couple of major cities half the world apart. You'll soon get tge idea.   

       *It is important not to use an inflatable globe in this case, as the results may well exhibit significant time-variant changes.
8th of 7, Sep 06 2014
  

       I had ETOPS all WRONG, sorry, I thought it was about the maximum distance you can travel on one engine. but more sensebly, its almost all about reliablity of the remaining enigine.   

       and i also thing lurch is much closer to me about the profit margins. but i still do think they are making big bucks   

       Iv been schooled, tips hat.   

       in my defence, i did not say to drop an engine the minute it fails, i was just saying to drop it if you're so far out at sea that that you can't make it back with the added weight + friction. which i think would be <1% of IFSDs
EkranoMan, Sep 07 2014
  

       //*It is important not to use an inflatable globe in this case..   

       Especially if it's filled with helium, when you're giving your presentation. . Strangely reminds me of the SF short story, where the Atlantic is yer common and garden ocean, but the Pacific is fractal in nature and so can never be crossed. Damned if I can remember the name of it..
not_morrison_rm, Sep 07 2014
  

       //Iv been schooled, tips hat. //   

       Wait 'til the spelling and punctuation pedants arrive.   

       Oh, wait - we're here.
MaxwellBuchanan, Sep 07 2014
  

       Yup. Lined up like vultures on the telegraph wires, waiting to swoop.   

       This is his first posting, so he gets a bit of leeway. Next time, it'll be the rubber truncheons and cattle prods right from the start…
8th of 7, Sep 07 2014
  

       You all talking Chinese to me, you know, but welcome [EkranoMan], to the asylum.
blissmiss, Sep 07 2014
  

       Well, as the Chinese say, you can throw a stick but you can't make soup from it. I think that's something we should all bear in mind.
MaxwellBuchanan, Sep 07 2014
  

       So, we should all think about making Chinese sticky bear soup ?
8th of 7, Sep 07 2014
  

       Is it easier to land an airliner on bear soup than on water? Perhaps yes, if it is sticky.
pocmloc, Sep 08 2014
  

       Much lower friction than water, because it's a properly constituted load-bearing surface ...
8th of 7, Sep 08 2014
  

       The Chinese can make a soup out of ANYTHING. That's a scientific fact.
bs0u0155, Sep 08 2014
  

       Indisputable. Unfortunately, "anything" encompasses melamine, rattus norvegicus, cement, lupins, and unreprocessed nuclear waste.
8th of 7, Sep 08 2014
  
      
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