old man emu Posted April 30, 2018 Posted April 30, 2018 There's clearly nothing wrong with the driver! My automotive and aircraft maintenance expertise leads me to deduce that the steering functionality of the car was adversely affected by the failure of the schveigle valve in the pressurized side of the power steering sub-assembly.
facthunter Posted May 1, 2018 Posted May 1, 2018 The NUT holding the steering wheel was excessively lubricated. Nev
Phil Perry Posted May 22, 2018 Author Posted May 22, 2018 The NUT holding the steering wheel was excessively lubricated. Nev According to the Police, she was five times over the DD Blood/Alcohol limit. Life saved by effective airbag deployment,. . .serious lower leg injuries though.
Marty_d Posted June 30, 2019 Posted June 30, 2019 Even if she hadn't hit the parked car, the paintwork would've needed work - she'd scraped a few hedges on the way. You can imagine a pedestrian or, judging by the time stamp, even school kids on their way home. She's damn lucky she didn't kill someone.
spacesailor Posted July 1, 2019 Posted July 1, 2019 Old habits !. In and before the 60's we (in the UK ) could drive to the pub have a couple of pints, and still go (by car) for an evening dinner later, have wine or beer with your meal then drive home without hitting anything in our way home again. The Good Old Days. LoL spacesailor
old man emu Posted July 1, 2019 Posted July 1, 2019 In the G.O.D.s if you hit something solid in your car, chances are that you would be severely injured as a result of your body colliding with the interior or the car. Now we travel securely attached to the inside of the vehicle with parts of the interior designed to pop out at you to restrict how far you move. The interior of the car is covered with energy-absorbing material. The cabin of the car is designed to remain undeformed while the rest of the car progressively crumples to dissipate energy and to reduce the momentum pulse. The introduction of random testing for alcohol has dramatically reduced the usual blood alcohol levels of affected drivers from pre-random testing levels. In 1982 the number was 1253 (23.6 deaths per 100,000 people). RBT was introduced on 17 December 1982, and from then on the fatality rate has steadily declined. In 2018, 353 lives were lost in traffic collisions in NSW. Unfortunately, the explosion in the use of drugs by that section of the population which has the least experience in driving has not reduced the crash rate. There will always be a base line of road fatalities due to unforeseeable circumstances (medical causes; true accidents, and vehicle or roadway failures). It is the foreseeable causes - intoxication, fatigue, stupidity that we must try to eliminate firstly by education, and secondly by penalty.
ClintonB Posted July 1, 2019 Posted July 1, 2019 On YouTube there is a Chevy Malibu being crash tested with an old model Chevy. It is very scary vision. I like old solid cars, but it is ridiculous how much caves in on the dummy. The new car crumples but pax compartment stays intact. Worth a look.
facthunter Posted July 1, 2019 Posted July 1, 2019 The crumple zones work but of limited help if the velocity gets higher. Side impact is less effective also as the distance for it to "work" is restricted.. Generally this is a good move but visibility has been sacrificed with thicker forward and centre pillars. Nev
old man emu Posted July 2, 2019 Posted July 2, 2019 Of course the value of crumple zones is limited by the Force of the impact, which is mainly dictated by the velocity of the bodies at impact. The reason for having crush zones is that they extend the time over which the impact force is applied, thereby reducing the rate of acceleration (or deceleration in an collision) of the struck object. In occupant safety, this reduction in the rate of deceleration helps the human body to survive the collision forces. In classical mechanics, impulse (symbolized by J ) is the integral of a force, F, over the time interval, t, for which it acts. It is the rate of change of Momentum [ATTACH]50146._xfImport[/ATTACH] [ATTACH]50148._xfImport[/ATTACH] Momentum = mass x velocity M = mv [ATTACH]50149._xfImport[/ATTACH] where F is the resultant force applied, t1 and t2 are times when the impulse begins and ends, respectively, m is the mass of the object, v2 is the final velocity of the object at the end of the time interval, and v1 is the initial velocity of the object when the time interval begins. The longer the time over which a force is applied reduces the magnitude of the impulse. Imagine you are playing golf. The idea is to move a ball of known mass over a distance. The usual way is to apply a large force to the ball for a short time: [ATTACH]50147._xfImport[/ATTACH] The impulse, J, is high because the force is applied for a very short time. And because the golf ball is very resistant to deformation, the majority of the force is used to acceleration the ball, i.e. to increase its velocity. Try getting the same distance when you hit a squash ball, which will deform at when the golf stick hits it. Another function of crumple zones is to dissipate the impact force by using it to deform the structure of the body and create noise, which is the result of directing impact force to the surrounding air to dissipate it as energy waves in air.
facthunter Posted July 2, 2019 Posted July 2, 2019 Bending the metal ends up as heat . Everything ends up as heat (entropy) at a low temperature level ,so not very useful. by then. Infra red and micro wave would be more effective than sound waves at moving heat energy. .You can make a lot of noise and not get anywhere.. Nev
spacesailor Posted July 2, 2019 Posted July 2, 2019 I still like the old idea of mass hitting lesser mass resulting in greater damage to the smaller vehicle, like the Arab state outlawing small cars, as they are less likely to protect the occupants, when hit by a 3 1/2 ton high speed car. spacesailor
facthunter Posted November 25, 2019 Posted November 25, 2019 Might is right??? Heavy Limmo's are for OIL sheiks and other posers. The issue is that due to mass difference the rate and extent of velocity CHANGE is more with the smaller vehicle. Kinetic energy KE is proportional to M (VSquared) so double the velocity and get 4 times the energy needs to be taken into account.. Nev
Marty_d Posted December 2, 2019 Posted December 2, 2019 I still like the old idea of mass hitting lesser mass resulting in greater damage to the smaller vehicle, like the Arab state outlawing small cars, as they are less likely to protect the occupants, when hit by a 3 1/2 ton high speed car. spacesailor So it's better to have two high speed 3.5 ton cars hitting each other? It'd be sheik, rattle & roll then.
facthunter Posted December 2, 2019 Posted December 2, 2019 The change of velocity with the lighter vehicle as more as the lighter thing actually will go backwards with a head on. If they are equal, it's like hitting an immoveable object. Brick wall/ big tree. Nev
onetrack Posted December 28, 2019 Posted December 28, 2019 5th Gear has a crash test video on YouToob. They centre the video around the crash of a Smart car at 70mph (112kmh) into a concrete crash barrier. The cabin strength of the Smart car is quite incredible, it still stays relatively intact, even after the 70mph impact. But the bottom line is, the occupant still would have died from internal injuries, caused by the massive deceleration. It's interesting to see how the small cars really bounce around after an impact, as compared to the big cars, that just stop in their tracks. I'll take a big car any day, over a small one.
old man emu Posted December 28, 2019 Posted December 28, 2019 The change of velocity with the lighter vehicle as more as the lighter thing actually will go backwards with a head on. If they are equal, it's like hitting an immoveable object. Brick wall/ big tree. Nev The big killer in collisions, and in fact including aircraft collisions with terrain, is the rate of change in momentum of each party to the collision. Momentum is properly defined as the arithmetic product of the magnitudes of the mass of the objects and their pre and post impact speeds: M = m x v . The symbol for Momentum is "p". The law of Conservation of Momentum states that the total Momentum of the objects before the collision is equal to the total Momentum of the objects after the collision, expressed as: (p1a + p2a) = (p1b + p2b) Where the subscripts 1 & 2 identify the two objects; "a" identifies the pre-impact value, an "b" identifies the post-impact value The value "Impulse" is defined as the "rate of change of momentum", or {(p1a - p1b ) + (p2a - p2b)}/ (t1 - t2), where (t1 - t2) is the length of time the objects are in contact.It is the magnitude of Impulse that determines the effects on structures, including the human body. Imagine how a cricket ball can do damage. Firstly, the keeper underhand throws the ball to Short Mid Wicket. Not much velocity involved and the ball can be caught without its causing pain. Then the bowler thunders in and the batsman lets if go through the the 'Keeper, whose gloves have padding which deforms as the ball hits them, increasing the time for the ball's momentum to be transferred to the gloves and 'Keeper. Next ball and the ball rises up and strikes the batsman on the ribs and stops. Ouch! Next ball the batsman nicks it to Second Slip. The ball changed momentum because it changed direction and maybe picked up a tad from the motion of the bat. The ball flies to Second Slip, who places cupped hands in the ball's line of flight, and as the ball collides with the hands, Second Slip starts to rotate away from the line of flight, which increases the time the ball is in contact with the hands until its velocity is zero. Here's a video in which Impulse is explained
facthunter Posted December 28, 2019 Posted December 28, 2019 I thought I knew about momentum until you brought CRICKET into it. It's not your fault I'm NOT a "cricket person" like everyone else was in my family was. F=Ma. Force= Mass x acceleration is another way of looking at it. What it means is if you change velocity rapidly you are a mess because of the large forces acting on you. Crumple zones give more distance (and time) for you to change velocity so less deceleration and less force acting on you to ruin your day. Nev
willedoo Posted December 28, 2019 Posted December 28, 2019 A bit like the Phantom and the concrete wall:
Litespeed Posted December 28, 2019 Posted December 28, 2019 Fellas, You do not want a big heavy car in a accident, especially a separate chassis 4wd. Great at low speed destruction of others but often kill everyone on board in a big one. They are mostly way too heavy and stiff to have adequate impact absorbtion in the impulse of a collision. They also love tipping over and killing all by squashing the roof, happens all the time. Sure bigger cars have bigger distances between the front and cabin but normally a lot more stuff that's heavy and crammed in there. Heavy cars have a great deal more inertia to absorb in such a small amount of time. Any forces it cant easily absorb will go to the cabin and its occupants. Yes in a ideal world, bigger and same safety features but bigger crush zones would be great but normally we drive compromises. The worst are the shortish and heavy for their size cars. Its all about the force being four times for a double weight increase. So it has to be four times as good in every area to save you. I have had a nasty in a big 7 series when hit by a 4wd turning into me at 90 km closing speed. The 4wd was toast and the BMW whilst fixable was written off by idiot insurance. In that case I would not want to be in a average car. No injuries to us but were in the 4wd. But I expect the smart would have done very well. Sure it would be punched sideways at a angle but that reduces a lot of the energy been stopped in a millisecond. Glancing blows are even better, if you can maintain a foward motion even at a large angle from straight- you are giving time for the forces to be absorbable and liveable on the body. Your crash zone can go from centimetres to metres. In the Smart test the angle shown really makes a huge difference to the effect compared to a flat hit. I am really impressed for how well it does compared to much bigger cars of its time or even today. Just watch all the biggest forces been transmitted around the cabin not into it. It might be tiny but its actually very safe. Extremely well engineered I have seen tests of smart vs much larger cars and it was safer- with the physics of crashes not all is what you expect. At uni we called it Lilliputian physics- because its is all a matter of scale and weight.
spacesailor Posted December 29, 2019 Posted December 29, 2019 I still prefer 1.3mtrs in front of myself & the little Corolla,s 0.75mtrs hitting mr at 160 klmsP hour total speed, Their crumple zone may be good thereticle. I witnessed a V8 motor sitting on the back seat of said corolla after a rear ender. Thankfully no rear passengers to mess the carpets. ( 60mph (not ks )). spacesailor
Marty_d Posted December 29, 2019 Posted December 29, 2019 On 28/12/2019 at 7:24 PM, willedoo said: A bit like the Phantom and the concrete wall: I liked how the outer panels of the wings kept going at much the same speed, going right past the concrete block as if the plane were flying through it instead of disintegrating against it.
Bruce Posted January 4, 2020 Posted January 4, 2020 There was an analysis of what sort of people bought urban 4wd's. They are nasty people who want the other party to die while they walk away.
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