Flemke - Is this your McLaren? (Vol 5)
Discussion
dom9 said:
flemke said:
Are you saying that the GT1 wing mirrors increased the Vmax above what it would have been with no mirrors at all?
I can see how those mirrors might have been superior to the standard mirrors of the time on the 993, even though the 993's mirrors were smaller.
I can also see how the GT1 mirrors might have been aerodynamically superior to no mirrors at all, not in terms of Vmax but in terms of managing the airflow and helping to generate more overall downforce.
However, relative to no mirrors at all (which in any case was not an option for Porsche as the GT1 racing car required a homologated road car basis), it is hard to see how Vmax would have been higher with the mirrors.
Do you have any documentation or source that you could share to enlighten us?
I feel like you're being a bit obtuse here, Flemke. There is no situation where 'no wing mirrors' is an option (really): Road cars must have them, race cars must have them. Cameras will still need to 'stick out'. Now, they're small enough that they could be on thin wing sections with a camera 'bullet' on the end, which may be optimum.I can see how those mirrors might have been superior to the standard mirrors of the time on the 993, even though the 993's mirrors were smaller.
I can also see how the GT1 mirrors might have been aerodynamically superior to no mirrors at all, not in terms of Vmax but in terms of managing the airflow and helping to generate more overall downforce.
However, relative to no mirrors at all (which in any case was not an option for Porsche as the GT1 racing car required a homologated road car basis), it is hard to see how Vmax would have been higher with the mirrors.
Do you have any documentation or source that you could share to enlighten us?
The point made was that wing mirrors contribute to drag, which is of course true, but can be optimised.
Cameras may replace mirrors but will still be there and still contribute to drag, as any external appendage would. But that's a much better solution for drag, right? However, what country is going to allow a car to be homologated for the road with thin, carbon blades sticking out? I'd guess none. So that won't be the solution. For pedestrian safety; you'll end up with something fairly bluff/ blunt that can be pushed back, fairly flush, with the door, when you hit the postman on his bike.
One solution you get to is something similar to the FXX, posted. Although better than say the wing mirror on my BMW it's not perfect from an aerodynamic point of view, though it's difficult to know what the airflow looks like in that location. My point is that there may well be an aerodynamic solution, benefitting Vmax, where you don't need the extra weight and complexity of cameras, screen, wiring etc over a piece of glass.
It's not the clearest picture but the point of the Porsche GT1 is that they absolutely did not have to look like that (look at its peers) and there were many, many other shapes of wing mirror housing that could have been applied to suit the regs. My understanding is that Porsche chose to create a fairly large 'bullet' where thickest part of the 'bullet' wasn't even the mirror (it's difficult to see). They created something with a higher frontal area because it had lower drag. In order to control the flow and wake behind the glass, it was quite long as well, which is why it looks so odd. Usually a longer object has more drag because it has more surface friction of the air passing over it but the airflow is easier to control, behind it giving a potential net gain in drag reduction.
So, yes, it was a lower drag solution, which is why they didn't just use 993 mirrors. I'll try and find the article as it was 20yrs+ ago and may have been a bit pre-internet (at least for me) and may have appeared in Race Car Engineering or alike. We used it as an example for my post-grad.
In any case, we agree that not all frontal areas are created equal. As your illustration suggests, a brick might have a smaller frontal area than a large artillery shell, but that would not mean that the brick was more aerodynamically efficient.
Regarding whether it would be possible to have a car without external mirrors, I could not say whether the important jurisdictions require the use of mirrors per se. In the practical sense, one would think that it is possible to have mounted on the A-pillars and rear wings lenses that are housed in nodules no larger than marbles, which would be more aerodynamically efficient than any external mirror shell currently on a production car.
flemke said:
Without getting into a debate about whether I was being "a bit obtuse", it appears that you and I use the English language slightly differently, and that may have accounted for the apparent misunderstanding.
In any case, we agree that not all frontal areas are created equal. As your illustration suggests, a brick might have a smaller frontal area than a large artillery shell, but that would not mean that the brick was more aerodynamically efficient.
Regarding whether it would be possible to have a car without external mirrors, I could not say whether the important jurisdictions require the use of mirrors per se. In the practical sense, one would think that it is possible to have mounted on the A-pillars and rear wings lenses that are housed in nodules no larger than marbles, which would be more aerodynamically efficient than any external mirror shell currently on a production car.
I agree in many ways - it'll be interesting to see how the problem is 'solved' because modern technology allows the camera to be so much smaller than the mirror (by bringing the viewing surface inside the car) but it'll be interesting to see how the "important jurisdictions" handle it.In any case, we agree that not all frontal areas are created equal. As your illustration suggests, a brick might have a smaller frontal area than a large artillery shell, but that would not mean that the brick was more aerodynamically efficient.
Regarding whether it would be possible to have a car without external mirrors, I could not say whether the important jurisdictions require the use of mirrors per se. In the practical sense, one would think that it is possible to have mounted on the A-pillars and rear wings lenses that are housed in nodules no larger than marbles, which would be more aerodynamically efficient than any external mirror shell currently on a production car.
How will OEMs show that cameras are as good (or better) in these unobtrusive positions? I suspect it'll be sold as a pedestrian safety benefit and we'll see them soon enough. And hopefully they are tucked out of the way; giving a benefit to drag (which will be sold on a fuel efficiency basis but we really know it's for Vmax
).But yes; perhaps I was rather clumsy with my million word explanation of "not all frontal areas are created equal". I should have known there would be a more elegant solution on this thread
dom9 said:
............., but we still have wing mirrors - genuine question (relating to my first point) - Why?
It *may* be because the rules & regs say they 'have to'?Edited by dom9 on Thursday 5th October 16:15
Ever wondered why the sun visors on the 12C hinge the wrong way and are completely utterly and totally useless?
It's because if they hinged the correct way they wouldn't pass the US safety regs' w.r.t an un-belted occupant impacting the hinge. McLaren wanted to do away with them altogether but another US reg states there must be an airbag warning label affixed to the sun visor.
Solution was hinging a 'sun visor' the wrong way (hinge is then no longer within area deemed to be an impact hazard for an un-belted occupant) merely so they could stick the required airbag warning label onto it.
Having just had a whole new CCTV system fitted to my site it is impressive how technology has advanced in the last 10 years.
I can see a time when there will be a number of cameras mounted down each side of a car and viewed on a panoramic screen with software that stitches all the cameras together. The camera could be low down/high up and tiny.
It will soon become a legal option if manufacturers decide it is the way forward.
But will it happen before we are all sitting in self driving cars????
I can see a time when there will be a number of cameras mounted down each side of a car and viewed on a panoramic screen with software that stitches all the cameras together. The camera could be low down/high up and tiny.
It will soon become a legal option if manufacturers decide it is the way forward.
But will it happen before we are all sitting in self driving cars????
Storer said:
I can see a time when there will be a number of cameras mounted down each side of a car and viewed on a panoramic screen with software that stitches all the cameras together. The camera could be low down/high up and tiny.
Mercedes already do that - I had the 360 Camera option in my e-class. They use a central front cam in the grill, one by the rear number plate, and one under each door mirror to give you separate views, and a stitched together from above 360 view. Works really well considering they have only 4 cameras. They not only stitch together, but change the aspect ratio etc. from each camera to make it look as real as possible.For those with the inclination to read up on the subject of rear view mirrors, or more formally 'Uniform provisions concerning the approval of devices for indirect vision and of motor vehicles with regard to the installation of these devices', the relevant UN-ECE Regulation is 46
http://www.unece.org/fileadmin/DAM/trans/main/wp29...
It includes references to camera based systems, but I lost the will to live fairly early on in the 90 pages of text! It refers to Reg 26 (external projections) too. I'm sure there'll be something in there about the position requirements inside a vehicle for the displays.
http://www.unece.org/fileadmin/DAM/trans/main/wp29...
It includes references to camera based systems, but I lost the will to live fairly early on in the 90 pages of text! It refers to Reg 26 (external projections) too. I'm sure there'll be something in there about the position requirements inside a vehicle for the displays.
Storer said:
Having just had a whole new CCTV system fitted to my site it is impressive how technology has advanced in the last 10 years.
I can see a time when there will be a number of cameras mounted down each side of a car and viewed on a panoramic screen with software that stitches all the cameras together. The camera could be low down/high up and tiny.
It will soon become a legal option if manufacturers decide it is the way forward.
But will it happen before we are all sitting in self driving cars????
I believe Nissan has a system that provides a full "top down" view.I can see a time when there will be a number of cameras mounted down each side of a car and viewed on a panoramic screen with software that stitches all the cameras together. The camera could be low down/high up and tiny.
It will soon become a legal option if manufacturers decide it is the way forward.
But will it happen before we are all sitting in self driving cars????
anniesdad said:
The Nur said:
I believe Nissan has a system that provides a full "top down" view.
Driven a few with the cameras fitted. Never once used it. Gimmic. I like having park sensors front and rear but 360 cameras. Nah...
national said:
Thoughts on this MSO R, one spider one coupe, matching specs, 688PS
I don’t see how the coupe differs from the HS?
Would love to know others thoughts
Without getting into the question of whether it makes any sense at all for a cabriolet to have a rear wing, the main difference between these cars and the HS is that on these cars the rear wing is dual-plane.I don’t see how the coupe differs from the HS?
Would love to know others thoughts
flemke said:
national said:
Thoughts on this MSO R, one spider one coupe, matching specs, 688PS
I don’t see how the coupe differs from the HS?
Would love to know others thoughts
Without getting into the question of whether it makes any sense at all for a cabriolet to have a rear wing, the main difference between these cars and the HS is that on these cars the rear wing is dual-plane.I don’t see how the coupe differs from the HS?
Would love to know others thoughts
flemke said:
Without getting into the question of whether it makes any sense at all for a cabriolet to have a rear wing, the main difference between these cars and the HS is that on these cars the rear wing is dual-plane.
Ah yes, I hadn’t noticed, thank you!I personally would love for you to explain about cabriolet and rear wing nonsense
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