The thing is the snow isn't a feature because its snow, but because the warm tunnel was at 100% humidity because of the snow. Cold and dry is more usual, but when you have massive snow, and deep cold, and a warm place, that's means steaminess. I guess the snow could have evaporated off the train and then condensed elsewhere, but the way I read it the final problem was condensation.
Juts like everybody who says 'if they can keep points unfrozen in Moscow at -20 why cant they do it here at -5?' and of course, its because its only -5..and the ruddy ice melts, runs into the cracks and then freezes again after its washed out all the antifreeze.
Very similar problem attains in aircraft. How come they can fly at -50C at 50000 feet, but they have to be de-iced on the runway?
I asked the pilot because we were both in the departure lounge whilst they rushed around with antifreeze 'because its wet slush on that wing, and this plane can, and has, crashed when it drips into the aileron hinge and freezes. Up high, there is no water to speak of.'
yeah, well that's all about micro management and elfin safety innit?
Management today is only about ticking all the boxes, and making sure others tick the boxes. one assumes the technology is perfect.
In the winter of 1963, someone decided that having blazing oil barrels alongside the diesel locomotives in Old Oak Common Depot was not a good idea and extinguished them all overnight. Next morning, they had to scrape together any steam locomotives they could, as the diesels were all out of action with waxy fuel.
We were somewhere around Barstow, on the edge of the desert, when the drugs began to take hold. I remember Pete Verdon saying something like:
They do, I saw a clip of a tug engine pulling out the dud trains, but I don't know if it would be rated for mainline use, or exactly what would be needed to couple up and run the systems on the carriages for longer journeys. What I was getting at, in such circumstances it would be a useful fall-back position to be able to use mainline locos as haulers and the tunnel services might only suffer minor disruption in the event of mass failure. Too late now though - it should have been thought about before.
We were somewhere around Barstow, on the edge of the desert, when the drugs began to take hold. I remember Andy Burns saying something like:
Well, that's handy. I suppose there simply weren't enough of them - afaik, the car/lorry shuttle service remained in operation and presumably employed all or most of the locos.
Well yes, they obviously needed to do that - and now seem to have done so. But only after they'd got several days' worth of disgruntled passengers clogging up all the stations. Surely they had ought to have adopted some more imaginative short-term solutions to prevent the problem from becoming a catastrophy?
Talking of catastrophy ... hypothetically .. ... So here we are with over 1400 passengers sat on defunct trains in semi darkness ... and the electrics finally short and a furious fire starts. Sitting there for 15 hrs would not be good would it ? You could have walked out in 15 hrs.
well he was right, cos I checked the accident reports.
"A major blow to ATR came when FAA issued an Airworthiness Directive (AD), restricting operations in icy conditions. This directive came as a result of investigations into the crash of American Eagle ATR 72 N401AM on October 31 and information provided by ATR. One explanation to the crash was an "ice-induced aerodynamic aileron lock"
and
"I´m a former ATR driver, so maybe I can give you some insight. There can be no doubt about it, in the early days of the ATR, they had some icing problems. Some of it can surely be blamed on the profile of the wing, I´m not going to pretend otherwise. But there is another aspect rarely discussed, namely the human factor in these accidents/incidents. It is not all the aircrafts fault, the biggest part of the blame must fall on the operation of the aircraft in these situations.
Before I go into specific accidents, I would like to explain what is happening to the wing of the ATR in Severe Icing Conditions. All of the ATR accidents/incidents related to Icing have happened in Freezing rain. What happens, supercooled waterdropplets strike the front of the wing and flow backwards over the de-icing boots before they freeze. Some of them make it to the area beyond the boots before they freeze. For the droplets to make it this far back they have to be of a certain size, IIRC they have to be bigger than 150 microns. In the certification criteria for Air Transport Aeroplanes dealing with flight into known Icing Conditions, states that the De-icing equipment of such an airplane must be able to deal with supercooled droplets of 40 microns. So it is evident that the aircraft getting into difficaulties because of Severe Icing are being operated outside their certification envelope. But we as pilots don´t have any equipment to measure the dropplet size, I get to that problem a little later.
When an ATR is flying in Severe Icing Conditions (freezing rain) with a dropplet size of at least 150 microns (flight tested at Edwards AFB) a ridge of Ice froms aft of the de-icing boots when they are operated. This ridge of ice starts to behave like a vortex generator, creating a very strong vortex behind it. Unfortunately the lowest pressure in this vortex is above the ailerons. Now, if the ice accumulation is completely equal on both wings AND the ailerons are both dead center, nothing happens as long as those conditions are met. Both ailerons have equal low pressure above them trying to suck them up. But this is not the perfect world. Ice accumulation is seldom absolutly equal and the autopilot is constantly making small roll corrections. As soon as the autopilot starts to make one aileron move up, the vortex grabs it and wants to slamm it to the stop. Initially the autopilot can handle the force, but a point is reached when it is overpowered by the vortex. The first indication the crew of the aircraft would have of that problem is a messeage on the ADU (Advisory Display Unit, the autopilot status sceen) saying.......AILERON MISTRIM. Moments later the autopilot disconnects and the bewildered crew is treated to a very fast aileron roll. From which they try to recover by pulling back on the yoke as the aircraft goes past inverted. Game over.
Now lets have a look at some accidents. The first accident caused by icing on the ATR was when an Alitalia (if I remember correctly) ATR crashed near Milan. The cause? The crew was climbing the aircraft in V/S mode on the autopilot through icing. The speed fell off, the aircraft stalled, autopilot disengaged and a quick aileron roll followed. They never pulled out of the resaulting dive.
The most famous ATR accident is the one near Roselawn Il. in the US where an ATR 72 crashed due to icing. They were trying to get into Chicago but the airport was closed due to weather. They were stacked in the holding over Roselawn at 5000 feet, on autopilot in freezing rain. They were holding in freezing rain for approx. 35 min. before it happened. Autopilot disconnected and a sharp aileron roll followed with a dive to the ground.
After this accident, ATR came under a lot of pressure from all and sundry. Boeing wanted to get a commercial exposure from the accident by trying to get the idea into peoples head that everything European was inherently dangerous. It was part of their early battle with Airbus. Various commercial pilot associations in the US jumped on the Boeing wagon and an intense lobbism was started to get the NTSB to be EXTRA careful in this case. As a resault the NTSB grounded all ATR?s flying in the US while the investigation was under way. The fact that the ATR that crashed had been flying in holding for over 30 min. In severe icing was completely lost on them. The ensuing investigation resaulted in the ATR becoming THE most studied aircraft in the world at the time with regards to icing. Nothing definate was found which indicated the ATR as a particulary dangerous in icing conditions. I´ve seen the uncut version of the tape shot on these experiments, and it is hard to understand how the aircraft could fly with all this ice on it. In the end the NTSB was forced to lift the grounding of ATR?s in the US.
Even though the test were inconclusive, ATR tried to fix the problem by extending the de-icing boots further aft with mixed resaults. Further more they issued a very compehencsive guidelines in the FCOM and the AFM on how to recognize and deal with severe icing. To recognize severe icing, it is recommanded that the pilots pay particular attention to water splashing or flowing on the front window when OAT is at or below
0° also pilots are advised to pay attention to unheated portions of the side windows for any sign of ice buildup. If one or both of these symptoms are present pilots are advised disconnect the autopilot asap and fly the aircraft manually. This is to prevent the autopilot from masking the effects the icing is having on the aircraft. Next step, according to the FCOM and the AFM is to leave and avoid conditions of severe icing, declaring an emergency if neccesary. Another point is never to let the speed go below 160kts.
Even after these guidelines were issued by ATR, we continued to receive one or two reports a year where ATR?s had departed controlled flight after flight into severe icing conditions on autopilot. Fortunately none of them resaulted in an accident. But it says a lot about the training and/or the attitude the people flying the aircraft. To have all these tips and recommidations and not following them is pure folly. I´ve flown the ATR in severe icing and by stricktly following the ATR procedures we didn´t have any difficaulties at all."
Not in this case. There was no build up of ice on the wings at all. Just snow, and the slipstream blew that off..but it was slushy. I'll let the ATR pilot above, speak for himself.
I was under the impression that the evacuation procedure was for a train to go down the serice tunnel and passengers to disembark go through the connneting corridors to the service tunnel and then be taken out. Failing that a train in the other tunnel that they cross to.
Didn't these trains fail fairly close to the french end maybe a few hours assuming everyone is capable of walking at all or even that far.
We were somewhere around Barstow, on the edge of the desert, when the drugs began to take hold. I remember Usenet Nutter saying something like:
Because while the train is standing at the tunnel for a while, it might be possible to knock up a quick set of shelves and/or a a mitred cupboard door.
We were somewhere around Barstow, on the edge of the desert, when the drugs began to take hold. I remember "Dave Plowman (News)" saying something like:
Jhc, talk about missing the point. IN THIS INSTANCE, it would have paid dividends, gettit?
That might work, a giant dyson on the air intake. Sand isn't sticky though, snow is. I guess you could recirculate or pass around the ouside of the "dyson" of the hot air after it's done it's cooling job to melt any build up of snow. Have to make sure you didn't overheat the incoming air though.
Not missing the point at all. Just pointing out it's stupid. There are lots of ways to cross the channel and time/cost decides which one you use. Putting up the cost and increasing the time is a no-no. Besides, if they had the foresight to allow for this they could have provided better snow shields at a fraction of the price.
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