As many modern saloons are quite aerodynamic
and
can travel at over 120 MPH easily
and
air flows faster over them compared to air flow under their body
and
Bernouli's principle states that in this case the object will get lift from below
does it mean cars can actually fly?
If not, then why some cars have downforce spoiler?
If yes, then why not all cars have similar spoilers?
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A neighbour had a rear spoiler fitted to his Mondeo many years ago. I reckon he would've achieved the same downforce by keeping it in his boot to the benefit of reduced drag.
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I don`t know what a car fly can do, but a door-mirror Spider can hang-on at 100+!
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Years ago,I drove down the same piece of road in two different Capris,same engine and gearbox-the only difference a few weeks in build date-one had no spoilers,the other had a chin and a boot spoiler-the second was notably more stable at speed.
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>> As many modern saloons are quite aerodynamic
>> and
>> can travel at over 120 MPH easily
>> and
>> air flows faster over them compared to air flow under their body
Fundamental mistake - it does not. If it did they would become undriveable at motorway speeds. They develop high pressure on the top to force the car on the road at higher speeds, just like a F1 car. Thats why all cars have much lower frontal aspects and lower sides to prevent flow under the car, and to make sure Bernouli is left out of the equation.
If the front does lift up, then you have trouble, as seen by flying racing saloon cars, sports cars and F1 cars.
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Isn't movilogo essentially correct in that a 3 box saloon car in section front to back is more or less wing shaped and will generate lift unless something is incorporated into the design to spoil the lift and/or generate downforce?
I'm pretty sure car manufacturers ignored this more or less, until about 1980 in some cases.
I'm sure you remember cars that went very light at motorway speeds. By about 90mph, my Mk3 Cortina was definitely rising at the front and scarily light on the steering, I thought then that it was trying to take off...
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Who else can remember the little 'ears' Mondeos sprouted behind the rear quarter lights after the first generation?
Described in one motoring magazine as being there 'to keep the back wheels behind the front'.
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>> Who else can remember the little 'ears' Mondeos sprouted behind the rear quarter lights after
>> the first generation?
>>
>> Described in one motoring magazine as being there 'to keep the back wheels behind the
>> front'.
It was too slippery, and the little ears broke up the windflow over the back. The effect of driving one without ears was really noticeable in side winds. The back really did try to steer the front.
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>> The effect of driving one without ears was really noticeable in side winds. The back really did try to steer the front.
'Weaving' they call it. Early teardrop-shaped Porsche 917s did it, at some sort of 200-plus warp speed at the latter end of the Mulsanne straight.
The successful (relatively non-lethal) version was the Kamm-tailed body developed by Ferry Porsche's sister's Porsche dealership. It campaigned as the Gulf Porsche 917. The rear end of the body swept up in a huge tail spoiler that made the car look like a blue and orange scorpion in profile. Below the spoiler there was nothing but immensely wide wheels, gearbox and howling flat-12 swathed in oil mist and so on.
One of the most magnificent projectiles of all time, but only for the brave and killed a few of them too. Including the great Mexican privateer Pedro Rodriguez whom I once saw at Brands driving a Ferrari (some number which I forget, 512 or something) LM, another very hairy rear-engined endurance racing monster.
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>> Who else can remember the little 'ears' Mondeos sprouted behind the rear quarter lights after
>> the first generation?
>>
>> Described in one motoring magazine as being there 'to keep the back wheels behind the
>> front'.
>>
Have you a good pic I'm trying to think of them but can't!
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'Have you a good pic I'm trying to think of them but can't!'
www.autotrader.co.uk/classified/advert/201241488258919/postcode/cm79hb
Picture number 2. They weren't very big but ran around the top / rear edge of the rear side window.
EDIT" Soz you said Mondeo. The Sierra had similar stability problems in side winds.
Last edited by: Fullchat on Wed 17 Oct 12 at 23:53
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>>
>> EDIT" Soz you said Mondeo. The Sierra had similar stability problems in side winds.
>>
AFAIK Mondies never had them.
Sierra's did, and the stories went that the prototypes didn't have instability problems, because the 1/4 windows didn't fit as well as the production version, and caused drag - something the add-on mouldings did.....
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Think he meant Sierras, I assumed he did anyway.
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>> Think he meant Sierras, I assumed he did anyway.
Correctly assumed. What'll your memory be like when you get your bus pass? ;>)
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Well I hope its better than yours!
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>> Who else can remember the little 'ears' Mondeos sprouted behind the rear quarter lights after
>> the first generation?
>>
>> Described in one motoring magazine as being there 'to keep the back wheels behind the
>> front'.
>>
Wasn't this the Sierra, we had a 1993 version without them and it felt terrible at speed in crosswinds.
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>> Isn't movilogo essentially correct in that a 3 box saloon car in section front to
>> back is more or less wing shaped and will generate lift unless something is incorporated
>> into the design to spoil the lift and/or generate downforce?
>>
>> I'm pretty sure car manufacturers ignored this more or less, until about 1980 in some
>> cases.
>>
>> I'm sure you remember cars that went very light at motorway speeds. By about 90mph,
>> my Mk3 Cortina was definitely rising at the front and scarily light on the steering,
>> I thought then that it was trying to take off...
Indeed yes my post explains how that effect has been eliminated by removing flow under the car. The car in airflow does not look wing shape.
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A friend after many Porsche 911s got a Renault GTS, one of those rear-engined V6 projectiles. One day the wind got under its nose at high speed and gave him a very serious brown trouser moment which he and the car survived. He went to see a fettler who attached a splitter thingy to its nose, and never had another problem with it.
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can a car fly?
Of course..
Mercedes built a flying car for the 1999 Le Mans..
www.youtube.com/watch?v=Ow3rxq7U1mA
A Mercedes CLR..
Car Levitates. Right?
Quote "The car flew right up in the air"
Last edited by: madf on Thu 18 Oct 12 at 13:38
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It is quite easy to make a car fly by going over a hump-back bridge too fast. At the moment of lift off I would imagine all the benefit of the diffuser spaces would be lost, and that it is only lack of traction that causes it to lose momentum and fall again.
Last edited by: Cliff Pope on Thu 18 Oct 12 at 21:32
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A friend in the late seventies ran a VW campervan. He swore it got light at the front at 70 and fitted a spoiler to combat the effect.
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Don't let us forget Hillman Imps.
IIRC they found the front lights were a little low for construction and use regulations and solved it it by raising the front suspension (perhaps L'es can enlighten us, as I believe he was around at that time?)
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there was no way an Imp would fly, it was safe to jack it up.
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>>there was no way an Imp would fly
Fly? Mine would barely make the speed limit. Any speed limit. Used to trawl up and down the A12 to Essex Uni in Colchester - that was a torment for someone living in rural Oxfordshire.
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>> Don't let us forget Hillman Imps.
>>
>> IIRC they found the front lights were a little low for construction and use regulations
>> and solved it it by raising the front suspension (perhaps L'es can enlighten us, as
>> I believe he was around at that time?)
That was certainly the story which circulated at the company. The centre of the headlights had to be a minimum of 24 inches from the ground. Imp-owning employees (including me) in the Experimental Department used to reduce the front wheel negative camber of their car to nominally zero by lowering the front by the means of fitting modified (lengthened) spring supports. The parts taken off the car would then be modified ready to be passed on to the next employee who needed them. Later production cars had the camber removed by a change to the design.
I remember the "Tear around the dotted line" Imp advert. tinyurl.com/8hxnlfy
Last edited by: L'escargot on Fri 19 Oct 12 at 08:40
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Can a car fly? - bathtub tom
