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Senna mystery


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#101 CSquared

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Posted 26 February 2014 - 02:38

Start watching Indycars on an oval, particularly Indianapolis or other lower-banked tracks.

Do you know of any examples I could start with before I spend 4 hours on youtube?  :wave:



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#102 gold333

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Posted 26 February 2014 - 05:36

The whole Senna incidend reminds me of the case of the moon landing or the assasination of JFK.

As usual in these cases there are plenty of "facts" which will undoubtly prove the truth of either version.

 

My subjective view regarding the onboard coverage is that the car tends to snap-oversteer for a fraction of a second while driving over a bump in the Tamburello curve. Maybe as a reaction to correct/prevent the car from spinning you can see a steering reflex to the right. Maybe its a combination of a reflection of light and poor TV quality but I there is a significant movement of the steering arm/steering rack visible according to a clockwise movement of the steering wheel. Well at least that is what I see.

Wouldn´t there be a anti clockwise movement of the steering wheel when it had been broken at that very moment?

This would indicate that the steering wasn´t broken before the impact.

In the following you can see Sennas helmet appear in the picture, while it was outside the picture going into Tamburello which indicates the G-Forces turning from right to left according to the steering direction.

It´s impossible to judge the cause of the Senna accident only by viewing the TV onboard coverage without having access to all the other relevant data but I share the opinion to let these data´s and true facts for the real experts and all the persons involved by the sad loss of Ayrton Senna.

Anyway thanks to f1steveuk for sharing a little more insight information.

 

The sustained and repetitive head movement to the left after loss of control has nothing to do with external forces acting on the drivers head,



#103 DRSdisabled

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Posted 26 February 2014 - 08:54

I used to work with the stress analyst who was at Williams at the time of the accident, he isn't the most reliable of characters but this is what he said;

100% the column failed before the impact and the telemetry confirmed this.
The data recorder was doctored to remove the evidence of failure.
Back at the factory there was a rear guard action to remove other similarly modified columns and prepare reports showing that it should have been acceptable.
Stress analysis of the steering column was typically done at this time as a pure couple applied at the steering wheel rim - they had little comprehension that the driver was applying axial and bending loads due to braking and cornering G loads on his body.

 

Well, if what your ex-Williams source says is true then we can pretty much close this discussion thread…

 

Did he specify it was the engine telemetry data recorder which was ‘doctored’ (which exists), or the main Williams data recorder (which was found unusable)?



#104 Nemo1965

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Posted 26 February 2014 - 16:55

rachael, on 25 Feb 2014 - 13:50, said:snapback.png

I used to work with the stress analyst who was at Williams at the time of the accident, he isn't the most reliable of characters but this is what he said;

100% the column failed before the impact and the telemetry confirmed this.
The data recorder was doctored to remove the evidence of failure.
Back at the factory there was a rear guard action to remove other similarly modified columns and prepare reports showing that it should have been acceptable.
Stress analysis of the steering column was typically done at this time as a pure couple applied at the steering wheel rim - they had little comprehension that the driver was applying axial and bending loads due to braking and cornering G loads on his body.

 

I don't believe it. Furthermore, that would mean that Frank Williams, Adrian Newey, Patrick Head, David Coulthard, Damon Hill and all committed perjury. Think about it. And that would also mean that they all would still be liable for persecution in Italy. AFAIK, there is no statue of limitation on perjury (not in Holland, that is...)



#105 Ross Stonefeld

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Posted 26 February 2014 - 17:06

I haven't read the court transcripts, but if that happened not everyone would be automatically guilty. Unless Coulthard and Hill said "no, the databox wasn't tampered with" what perjury have they committed? And even then, it'd only be perjury if they knew they were lying rather than repeating what they were told.

 

I think it's far fetched personally, but it's almost not the most far-fetched scenario. Given the legal issues with a racing death in Italy it might be better to say "sorry, there's no data"



#106 Nemo1965

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Posted 26 February 2014 - 18:46

Ross,

 

Ofcourse, Coulthard and Hill could have been totally kept out of the decision and actions to wipe the data-recorder. But then there remains the changed steering column. 

 

First of all, Hill and Coulthard have testified that the moving of the steering column seen in the onboard footage of Senna at Imola was normal. Secondly, Coulthard even participated in a demonstration to show that fact. Thirdly, there is no way that Coulthard and Hill would not have been witness to the fact that the steering columns were afterwards altered to give Senna's steering column the feign of normalcy.

 

If the story of Rachaels friend is true, which I don't believe, we are talking about a conspiracy that dwarfs Singapore 08 to an absurd play for little boys... And Hill and Coulthard and Newey and Head and Williams were in it. 

 

No. Way.



#107 rachael

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Posted 26 February 2014 - 21:02

Not so much friend as colleague, it's possible I misunderstood what he was saying but I think the intention was to create doubt that the column was made to the correct design - so they removed similar modified columns from stores and changed the drawings to make it look like a manufacturing error.  Even now plenty of things go on that the drivers are not aware of - 'What the eye doesn't see the heart doesn't grieve over'



#108 mzustak

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Posted 26 February 2014 - 21:14

Just wanted to say 'thank you' for some of the nice comments posted.

It doesn't make a difference to the arguments being discussed, but is really appreciated. 

 

KR

Martin



#109 Nemo1965

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Posted 26 February 2014 - 21:53

Not so much friend as colleague, it's possible I misunderstood what he was saying but I think the intention was to create doubt that the column was made to the correct design - so they removed similar modified columns from stores and changed the drawings to make it look like a manufacturing error.  Even now plenty of things go on that the drivers are not aware of - 'What the eye doesn't see the heart doesn't grieve over'

 

Ok. Because if he really was telling you that Williams have put in place a full blown cover-up, he should either go to the authorities - Italian, English, FIA- whatever or forever hold his tongue... I am rather annoyed by the idea that either a. he is telling the truth and there is a huge scandal involved with people still working in F1 or b. he is trying to impress people by telling lies. Annoying in a whole other way.

 

Regarding the drivers: this is something that I am sure Hill would not shut his eyes against. 



#110 ensign14

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Posted 26 February 2014 - 22:28

It would be a piece of cake to uncover a cover-up by Williams.  There's always an audit trail.  Plus you'd have Hill and Coulthard at least worried about their safety behind the wheel.  I don't believe there was a Williams cover-up for one nanosecond.

 

Occam's razor applies.  Senna made mistakes from time to time.  He was driving a car right on the edge without the advantages of the car behind.  One slight error had the consequences we know.  Far more logical and believable than the alternatives.



#111 kayemod

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Posted 26 February 2014 - 23:17

It would be a piece of cake to uncover a cover-up by Williams.  There's always an audit trail.  Plus you'd have Hill and Coulthard at least worried about their safety behind the wheel.  I don't believe there was a Williams cover-up for one nanosecond.

 

Occam's razor applies.  Senna made mistakes from time to time.  He was driving a car right on the edge without the advantages of the car behind.  One slight error had the consequences we know.  Far more logical and believable than the alternatives.

 

All perfectly true, Senna made a mistake, as he'd done quite a few times before. I think some of us are losing sight of the fact that the only reason we're discussing this at all is because of the tragic outcome. In 999 cases out of 1000 he would probably have walked away pretty much uninjured, this would be a more or less forgotten racing incident, but for the outcome of the suspension breakage. I can't really see the cause of Senna's crash as being in itself terribly important, though obviously some will disagree.



#112 Hank the Deuce

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Posted 26 February 2014 - 23:29

not only that, but it seems a typical human-nature quest to define Senna's accident and subsequent death on One Big Thing... I'd think that this accident - like most, whether on track or out in the world at large - are a function of a number of small occurances whose consequences might possible be less-than-significant if they happened in isolation - converging on a single event, creating something far more catastrophic.

 

For mine, the "official" scenario - cold tyres, low ground clearance, an uneven surface, a high-speed corner with little in the way of run-off, an unpredictable and recalcitrant race car, and a driver working very hard to leave his opposition in his wake - is more than enough to explain how it all went wrong, regardless of Senna's undisputed skill.



#113 DRSdisabled

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Posted 27 February 2014 - 00:04

All perfectly true, Senna made a mistake, as he'd done quite a few times before. I think some of us are losing sight of the fact that the only reason we're discussing this at all is because of the tragic outcome. In 999 cases out of 1000 he would probably have walked away pretty much uninjured, this would be a more or less forgotten racing incident, but for the outcome of the suspension breakage. I can't really see the cause of Senna's crash as being in itself terribly important, though obviously some will disagree.

I agree, it would be a more or less forgotten racing incident because Senna would tell us what exactly happened :-)

I also agree the cause is not terribly important - it won't bring him back - but it's like asking why people climb the Everest. "Because it's there...."   



#114 CSquared

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Posted 27 February 2014 - 06:54

Occam's razor applies.  Senna made mistakes from time to time.  He was driving a car right on the edge without the advantages of the car behind.  One slight error had the consequences we know.  Far more logical and believable than the alternatives.

 

That theory does not explain all the known facts, such as:

1. What the car did (straightening out and going perfectly straight all the way to the wall).

2. The steering wheel movement before the accident.

3. The steering column being broken. 

4. The telemetry that shows the steering being broken (this is new information for me that I learned from the book that started this thread). 

5. It was a flat out corner for any car, not a place where a driver could even really make a mistake.

 

You have to make a large number of assumptions to explain those things. The theory that the steering column broke explains all the known facts and requires no extraneous assumptions, therefore it's the one favored by Occam's razor.



#115 Spinnekop

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Posted 27 February 2014 - 11:51

From what I observed at the time and viewing the available telemetry and footage to be found on the net It and reading posts from someone who had direct access to the evidence during the investigation (thanks for sticking you're neck out Steve :up: ) pretty much giving a proper technical run down explaining what caused the accident completely consistent with the behaviour of the vehicle prior to the accident that I saw I just never fully understood why it behaved in that maner.

 

 It was a very high speed section so the rear bottoming out makes complete sense for the car understeering (actually not even understeering as AS didn't apply steering lock perhaps expecting the car to regain traction again very soon and didn't want steering lock applied when the car regained traction) straight off the corner. Rear bottoming out would have taken all the steering away and unstuck the back end.

 

Occums razor is applied when you don't know the reason so you choose the most likely cause. The car bottoming out causing loss of steering is by far the most plausible explanation.

 

Hopefully the Ancient Aliens watching conspiracy theorists can just rationally look at the evidence.

 

People coming with evidence like steering movement traces (that is called steering feedback and if I was in a car and all of a sudden the steering wheel became very still in my hands THEN I'd be worried) or matelurgy reports showing 80% fatigue fractures and 20% shearing on impact at the very least means there was a fifth of the steering column fully intact and more than enough to maintain control of the steering (In my line of work I do a fair amount of non destructive testing of metal structures and 80% prevelance of fatigue fractures does not mean the column was sheared almost all the way off at all- it means there were indications of stress fractures through 80% of the metal- you may well gett a similiar result if you tested a drive shaft of a powerful car thats done 100k miles).

 

To the tinfoil hat wearers citing how you can see the column broke 3 seconds before he left the the track with their interpretations of inboard footage- what :eek: have you ever driven a car before? Senna would've noticed straight away and slammed on the brakes immediately! He didn't even turn the wheel back and forth to confirm it had broken-because he knew it wasn't.

 

It was a very unfortunate ACCIDENT so could the conspiracy theorists please rather go back to looking for Nessie and proving how we received extraterrestrial assistance building the pyramids :evil:



#116 Ross Stonefeld

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Posted 27 February 2014 - 13:01

 

That theory does not explain all the known facts, such as:

1. What the car did (straightening out and going perfectly straight all the way to the wall).

 

 

 

Well, it continued to turn a little bit. It exhibited the behaviour of a car with high speed understeer. Whether that's a steering/suspension malfunction, going around the corner too fast, momenatry loss of grip, tire failure, etc, et al.


#117 CSquared

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Posted 27 February 2014 - 22:21

 

Well, it continued to turn a little bit. It exhibited the behaviour of a car with high speed understeer. Whether that's a steering/suspension malfunction, going around the corner too fast, momenatry loss of grip, tire failure, etc, et al.

 

I disagree, of course:

1. In the video from Schumacher's car, Senna's car looks to me to straighten out and go straight.

2. In the video taken from the camera that's past Tamburello, it looks to me like the car is at the same angle in the first frame as in the last. I.e., it is not rotating.

3. The data in the book this thread is about shows the car going straight all the way to the wall.

4. Senna had enough time and traction to brake from 190 to 135 mph, but still did not steer away from a relatively shallow impact angle with the wall.

 

I have to say, though, Ross, I appreciate you even trying to address this issue. Everyone else just apparently tries to ignore it.



#118 ensign14

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Posted 27 February 2014 - 23:03

 

That theory does not explain all the known facts, such as:

1. What the car did (straightening out and going perfectly straight all the way to the wall).

2. The steering wheel movement before the accident.

3. The steering column being broken. 

4. The telemetry that shows the steering being broken (this is new information for me that I learned from the book that started this thread). 

5. It was a flat out corner for any car, not a place where a driver could even really make a mistake.

 

You have to make a large number of assumptions to explain those things. The theory that the steering column broke explains all the known facts and requires no extraneous assumptions, therefore it's the one favored by Occam's razor.

 

 

Except they are not known facts; they are inferred from available evidence.  Indeed an informed eyewitness asserts 3 was caused by the impact and it's obvious 5 can't be true as a driver can make a mistake anywhere.  The theory that the steering column broke is not supported by any independent testimony.



#119 Ross Stonefeld

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Posted 28 February 2014 - 00:23

I'm not really familiar with the details of the telemetry. When did he get on the brakes? Because only losing 60mph at those speeds in an F1 car isn't much. Did he try to fight it before he gave up and braked? Because if he really did have a steering problem or other failure, I think he'd have been on the brakes immediately and would have shed more speed. 

 

But, you have to remember he's off line and on a really rough bit of pavement. The car's not going to do much braking or turning on that surface, even if everything is fine. 



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#120 George Costanza

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Posted 28 February 2014 - 02:25

Power Steering Failure; Patrick Head asked that question to himself when it happened....



#121 PayasYouRace

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Posted 28 February 2014 - 08:14

 

- If the diffuser stalled, causing sudden reduction in traction at the rear, wouldn't the car spin? 

 

 

I can have a crack at that one. The diffuser works by matching the air pressure at the exit to ambient, forcing faster and therefore lower pressure air under the floor of the car. What that means is that the downforce produced by the diffuser is much further forward along the car. The centre of pressue is closer to neutral. The car would experience a significant loss of downforce, but not a significant change in balance. Remember this is before the teams were really linking the flows of the diffuser and rear wing in the way we're familiar with today. It would not be like the RW breaking, leading to a sudden loss of rear downforce and a spin.

 

Tangent: See Schumacher's RW failure in Hungary 1992 for an interesting comparison. It that was on a straight, but the slightest turn and he was spinning.

 

Stalling a diffuser is a situation that may not be easily recovered without slowing the car considerably. Back then the cars were very aerodynamically unstable. Less was understood about designing their aero for the less than ideal case. In the active suspension era they didn't even have to worry about that, because the car kept the same attitute at all times. You can see that by the number of airborne cars that era saw. Patrese at Estoril being a particularly good example because it was in an active Williams with an earlier version of the FW16s aero philosophy.

 

Taking a step back, unstalling a diffuser isn't simply a matter of returning the speed at which it first stalled. As an example of this, go to your bathroom or kitchen, and slowly open the a tap. You'll soon have a steady, laminar (clear looking) stream from the tap. You'll then reach a point where the flow becomes turbulent (cloudy looking). If you start turning off the tap, you have to close it much more than you opened it to return to laminar flow. (This depends on what kind of tap you have, particularly what's on the end of the spout.)

 

If the diffuser stalled on Senna's car, it likely had an extreme recovery point like I've just described. The accident happened far to fast. The time before a point of no return is far less than the time between whatever failure and hitting the wall. I haven't read the book yet, so I don't know of the exact details are there, but for the sake of argument, if the diffuser had recovered when he crossed the white line, then he was past the point of no return. The car would have been travelling too fast and with not enough space before the wall for him to do anything about it.

 

That's why I find a lot of strength to this argument which I had never considered before. It also accounts for the behaviour of the car during the accident, and I shared your concerns. That's why I usually leant towards the steering column failure, but now I'm drifting away.



#122 Nemo1965

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Posted 28 February 2014 - 11:11

Ross said elsewhere in this thread that Senna's accident looked like an oval-accident, and that made me think about Gordon Smiley's accident at Indy. AFAIK, other Indy-drivers have always said that Smiley made the wrong correction: the car oversteered, and Smiley reacted like you would do on a roadcourse: he applied opposite-lock. Then, just by virtue of the speed, the grip restored, the car just steered straight into the wall...

 

Adrian Newey has said that Senna's car OVERSTEERED in Tamburello (for whatever reason, Senna reacted very quickly (with less steering imput as Smiley, obviously), the cars grip was 'restored' but in a fatal direction: that of heading at the wall. I have always assumed that if you have a car with a diffuser and the speed is very high, you have massive downforce, the car basically wants to travel straight on. It is not untill you have slowed down the car considerably untill the mechanical side of the grip takes over. If you look at Senna's accident that way, it is not strange to see how little 'change' there was in the direction of the car after it left the track.



#123 PayasYouRace

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Posted 28 February 2014 - 12:18

Ross said elsewhere in this thread that Senna's accident looked like an oval-accident, and that made me think about Gordon Smiley's accident at Indy. AFAIK, other Indy-drivers have always said that Smiley made the wrong correction: the car oversteered, and Smiley reacted like you would do on a roadcourse: he applied opposite-lock. Then, just by virtue of the speed, the grip restored, the car just steered straight into the wall...

 

Adrian Newey has said that Senna's car OVERSTEERED in Tamburello (for whatever reason, Senna reacted very quickly (with less steering imput as Smiley, obviously), the cars grip was 'restored' but in a fatal direction: that of heading at the wall. I have always assumed that if you have a car with a diffuser and the speed is very high, you have massive downforce, the car basically wants to travel straight on. It is not untill you have slowed down the car considerably untill the mechanical side of the grip takes over. If you look at Senna's accident that way, it is not strange to see how little 'change' there was in the direction of the car after it left the track.

 

Not really. Remember that when we talk about aero grip vs. mechanical grip we're talking about how hard the tyres are being pushed into the ground vs. the vehicle dynamics from suspension geometry. Adding the former doesn't detract from the latter (without getting into balance issues). Having more downforce will make the car turn easier. It's the massive loss of downforce that made the car want to travel straight on, and that's why diffuser stall makes a lot of sense to me.



#124 Nemo1965

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Posted 28 February 2014 - 12:35

Not really. Remember that when we talk about aero grip vs. mechanical grip we're talking about how hard the tyres are being pushed into the ground vs. the vehicle dynamics from suspension geometry. Adding the former doesn't detract from the latter (without getting into balance issues). Having more downforce will make the car turn easier. It's the massive loss of downforce that made the car want to travel straight on, and that's why diffuser stall makes a lot of sense to me.

 

Well, I am not an engineer, but I think you are mistaken. If you, for instance, have a setup with a lot of downforce on the front of the car, (by virtue of a large wing or a large venturi-effect on the front of the car) the car can move in a constant radius very fast... but changing the radius with a lot of downforce is much harder than changing the radius with low downforce. And basically, that is going through a medium speed or slow corner: you are making a circle and while you are making the circle you change the radius. You approach the apex from the side (wide radius, brake, turn in (narrow radius) and then at the apex apply throttle (increasing the radius). 

 

That means that if you have a large front wing on your car, it will give you better constant high speed in fast corners, but understeer in medium and slow corners.

 

Right?

 

EDIT: I am not discarding your opinion on what happens when the diffuser stalls and the subsequent role it could have played in Senna's accident. I am merely commenting on the idea that more downforce means easier turning of the car, which I don't believe (but I am open for learning!)


Edited by Nemo1965, 28 February 2014 - 12:53.


#125 Ross Stonefeld

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Posted 28 February 2014 - 12:59

Why would lots of front downforce give you understeer? Unless you mean that in the slow corners it's less effective?



#126 stuartbrs

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Posted 28 February 2014 - 13:11

Until we hear from a driver of these (unique) 94 era cars on this forum, with experience of these circumstances, then speculation on what the driver was doing/trying to do/reacting to, is really just speculation...



#127 Nemo1965

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Posted 28 February 2014 - 13:36

Why would lots of front downforce give you understeer? Unless you mean that in the slow corners it's less effective?

 

Newtons law of gravity. Let me quote Brian Beckman from his excellent series of articles: The physics of racing. 

 

The first law: a car in straight-line motion at a constant speed will keep such motion until acted on by an external force. The only reason a car in neutral will not coast forever is that friction, an external force, gradually slows the car down. Friction comes from the tyres on the ground and the air flowing over the car. The tendency of a car to keep moving the way it is moving is the inertia of the car, and this tendency is concentrated at the CG point.

 

Coming back on what I said: if a car has little downforce (especially on the front of the car) the force that you need to change the straight line as above stated, should be considerably LESS than if you have a car with a lot of downforce (especially on the front). Which stands to reason, because why else would F1 engineers want to put a front wing on a F1 car? That is to be able to maintain a certain line through a corner at a higher speed, right? 

 

If you drive through a corner, the momentum wants you go straight, that means: through the imaginary center of the circle you are making with your car, in a left hand corner that would be, oh, about 15 degrees to "the right". If the force applied to the steering wheel and the friction of the tyres that are pointing at the right angle to the desire of the driver, are greater than the force that wants the car and its driver to travel straight, you will make the desired radius. Meaning: you get your car through the corner.

 

Again, I am not an engineer, I've not driven single-seater cars, I am just trying to follow logic. For me it stands to reason that if you design a car that has more and more downforce, you will need more force to change to change any 'straight line' that car is making at any certain moment, and this force is greater at higher speeds. Otherwise every engineer could say to a driver that complains over understeer in fast corners: 'Hey, why don't you turn the wheel more?' 

 

Which, ofcourse, the driver can't do, because he will know that in a fast corner, too much lock will change the understeer in oversteer... which brings me back to Senna and his accident: I think Newey was right, in a sense. Senna took another line into Tamburello (compared to the lap before), because he 'felt' understeer, the car oversteered, he reacted, the front gripped again and then veered towards the wall in a straight line.

 

Again, I am open for any correction from more learned posters...


Edited by Nemo1965, 28 February 2014 - 13:40.


#128 Ross Stonefeld

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Posted 28 February 2014 - 13:51

I still don't understand how more grip in the front tires, especially in balance terms vs the rear, is understeer.

 

The 'more force' you need to turn the car at high speed is in the wheel. Without power steering it gets very 'heavy'. 



#129 PayasYouRace

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Posted 28 February 2014 - 14:12

Well, I am not an engineer, but I think you are mistaken. If you, for instance, have a setup with a lot of downforce on the front of the car, (by virtue of a large wing or a large venturi-effect on the front of the car) the car can move in a constant radius very fast... but changing the radius with a lot of downforce is much harder than changing the radius with low downforce. And basically, that is going through a medium speed or slow corner: you are making a circle and while you are making the circle you change the radius. You approach the apex from the side (wide radius, brake, turn in (narrow radius) and then at the apex apply throttle (increasing the radius). 

 

That means that if you have a large front wing on your car, it will give you better constant high speed in fast corners, but understeer in medium and slow corners.

 

Right?

 

EDIT: I am not discarding your opinion on what happens when the diffuser stalls and the subsequent role it could have played in Senna's accident. I am merely commenting on the idea that more downforce means easier turning of the car, which I don't believe (but I am open for learning!)

 

 

Newtons law of gravity. Let me quote Brian Beckman from his excellent series of articles: The physics of racing. 

 

The first law: a car in straight-line motion at a constant speed will keep such motion until acted on by an external force. The only reason a car in neutral will not coast forever is that friction, an external force, gradually slows the car down. Friction comes from the tyres on the ground and the air flowing over the car. The tendency of a car to keep moving the way it is moving is the inertia of the car, and this tendency is concentrated at the CG point.

 

Coming back on what I said: if a car has little downforce (especially on the front of the car) the force that you need to change the straight line as above stated, should be considerably LESS than if you have a car with a lot of downforce (especially on the front). Which stands to reason, because why else would F1 engineers want to put a front wing on a F1 car? That is to be able to maintain a certain line through a corner at a higher speed, right? 

 

If you drive through a corner, the momentum wants you go straight, that means: through the imaginary center of the circle you are making with your car, in a left hand corner that would be, oh, about 15 degrees to "the right". If the force applied to the steering wheel and the friction of the tyres that are pointing at the right angle to the desire of the driver, are greater than the force that wants the car and its driver to travel straight, you will make the desired radius. Meaning: you get your car through the corner.

 

Again, I am not an engineer, I've not driven single-seater cars, I am just trying to follow logic. For me it stands to reason that if you design a car that has more and more downforce, you will need more force to change to change any 'straight line' that car is making at any certain moment, and this force is greater at higher speeds. Otherwise every engineer could say to a driver that complains over understeer in fast corners: 'Hey, why don't you turn the wheel more?' 

 

Which, ofcourse, the driver can't do, because he will know that in a fast corner, too much lock will change the understeer in oversteer... which brings me back to Senna and his accident: I think Newey was right, in a sense. Senna took another line into Tamburello (compared to the lap before), because he 'felt' understeer, the car oversteered, he reacted, the front gripped again and then veered towards the wall in a straight line.

 

Again, I am open for any correction from more learned posters...

 

Firstly it's Newton's Laws of Motion. His law of gravity doesn't really apply here.

 

I think I can see where you're coming from but I don't think it's right. By adding downforce you're adding to the force that you can apply to change your direction via the tyres, and thus how easy it is to change direction. The inertia is the same (the car has the same mass) but the force you can apply to it is greater.

 

The reason for having front and rear wings is to balance the downforce, providing front and rear tyres with an equal ability to grip the road. You need to have the fronts and rears providing the same force. Add too much front wing and you can apply more force at the front than at the rear and you spin. Take it out and the front tyres can't apply the force required to turn the car.

 

Now downforce can make the steering heavy for the driver. It makes the wheel harder to turn, but the car will turn. If you didn't have the downforce, you'd turn the wheel easier, but the front wouldn't grip and you'd go straight on anyway (so you'd have to slow down more to take your corner).

 

In fact I think I can see where your misunderstanding stems from. Adding downforce doesn't add inertia to the car, but it adds the ability to overcome that inertia. I have bolded the relevant misunderstandings.


Edited by PayasYouRace, 28 February 2014 - 14:12.


#130 rallen

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Posted 28 February 2014 - 15:44

Very interesting topic. I have always found it - indeed any mystery deeply interesting. I must admit though that I don't have a view either way on this though so I am not in one camp or the other.

 

Can I just ask though that people stop referring to other people as the foil hat brigade or labelling them disparagingly as conspiracy theorists just because they have a different opinion. It is disrespectful emotive and used to humiliate or close down other people. That somehow it's fine for them to have that view but they are idiots or fools. All the views expressed on hear from both sides have been well expressed and not ridiculous.

 

As I said I don't have an opinion on what happend as i don't know - I remember it well as I watched it live & my initail reaction was one of disappointment as i was looking forward to a great battle and I thought the race would be boring now. It never occurred to me that it would prove fatal.

 

The cause of the accident has been debated well (and I hope will continue to be debated) however I want to focus on a few other points not related to why.

 

1. Can anyone explain why there wasn't even a basic tire wall there? I remember safety well back there and even then it seems odd that there wasn't one there (especially after poor Roland the day before) 

 

2. Can someone actually explain how the tires could have set the 3rd fasted lap on the race on lap 6 and then be cold enough to be mentioned as a possible cause happend on lap 7? I am not disputing this as a valid theory - I just don't understand it, I know it has been mentioned about but if someone could kindly help me understand this I would appreciate it. 

 

3. I have read conflicting reports about the black boxes and data recorders being damaged after the accident or disappearing - or just being damaged in the initial accident. Can anyone give me more details on this. Was it purely accident damage or does it 'appear' there was more to it than that.

 

Also f1steve - thanks for your comments - you said you didn't really feel you could say more which I respect - but can you explain why this information is sat on and not available to the public - esp if it does not blame the Williams team or would result in any prosecutions. Why is it being hidden? and isn't it immoral and wrong to sit on this stuff?



#131 Michael Ferner

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Posted 28 February 2014 - 16:11

Very interesting topic. I have always found it - indeed any mystery deeply interesting. I must admit though that I don't have a view either way on this though so I am not in one camp or the other.

 

Can I just ask though that people stop referring to other people as the foil hat brigade or labelling them disparagingly as conspiracy theorists just because they have a different opinion. It is disrespectful emotive and used to humiliate or close down other people. That somehow it's fine for them to have that view but they are idiots or fools. All the views expressed on hear from both sides have been well expressed and not ridiculous.

 

I couldn't agree less - just the last few posts have shown that some people here talk a lot, and a lot about things they don't have the slightest clue about.

 

2. Can someone actually explain how the tires could have set the 3rd fasted lap on the race on lap 6 and then be cold enough to be mentioned as a possible cause happend on lap 7? I am not disputing this as a valid theory - I just don't understand it, I know it has been mentioned about but if someone could kindly help me understand this I would appreciate it. 

 

 

That one is very easy: according to two independent sources (Autocourse and Motorsport aktuell), Senna didn't record the 3rd fastest time of the race, but 22nd. Like so much that is reported as "fact", it is in fact twaddle.



#132 PayasYouRace

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Posted 28 February 2014 - 16:16

 

1. Can anyone explain why there wasn't even a basic tire wall there? I remember safety well back there and even then it seems odd that there wasn't one there (especially after poor Roland the day before) 

 

 

 

Possibly the most infuriating issue of the lot. Just about knew there was a problem, but because of the river and the lack of space to increase the run-off space they decided that was that and nothing would be changed. Nobody seemed to think of moving the corner inwards (or building a chicane), which were both evidently possible as it was done in time for 1995. There didn't seem to be any motivating factor in fixing it until the worst happened.

 

 

That one is very easy: according to two independent sources (Autocourse and Motorsport aktuell), Senna didn't record the 3rd fastest time of the race, but 22nd. Like so much that is reported as "fact", it is in fact twaddle.

 

Senna's lap 1, a 1:44.068, was the 22nd fastest lap of the race. I would be amazed if his lap 5 (hope I got that right) was slower than that. Something doesn't add up there. Is it because of the red flag that the last lap didn't count?

 

What was that about talking about things which one doesn't have a clue about?



#133 Ross Stonefeld

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Posted 28 February 2014 - 16:25

Forix is confusing on that. Because he did one full racing lap after the restart no? So he would have come out of the final turn at pretty close to normal speeds, done one timed lap, and then crashed in Tamburello at the start of the next lap.

 

Even going lap by lap and looking at the total race time up until that point, I can't figure out Senna's laptime. 

 

1 Lap 1'44.068
2 Laps 4'15.274 (2:30 laptime)
3 Laps 6'49.890 (2:34 lap)
4 Laps 9'26.520 (2:36 lap)
5 Laps 12'01.301 (2:35 lap with Senna first across the line)
6 Laps 13'32.681 (1:32 lap and Schumacher is listed as the leader, with Senna in 22nd on 12'01.301)
 
There was at least one full green flag lap before Senna's accident wasn't there? 


#134 PCC

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Posted 28 February 2014 - 16:26

I couldn't agree less - just the last few posts have shown that some people here talk a lot, and a lot about things they don't have the slightest clue about.

I think rallen's point was that it's both possible and more productive to correct people's mistakes without insulting and belittling them.



#135 Michael Ferner

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Posted 28 February 2014 - 16:35

How do you explain to someone that you can't cure understeer by applying more steering lock??? When it's obvious that the person who's talking doesn't know a thing about the subject he's talking about, every effort to "correct mistakes" is not possible and productive, but futile and a waste of time.


Edited by Michael Ferner, 28 February 2014 - 16:37.


#136 Ross Stonefeld

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Posted 28 February 2014 - 16:37

Because that's a misunderstanding, not a refusal to accept information.



#137 PayasYouRace

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Posted 28 February 2014 - 16:56

 

Forix is confusing on that. Because he did one full racing lap after the restart no? So he would have come out of the final turn at pretty close to normal speeds, done one timed lap, and then crashed in Tamburello at the start of the next lap.

 

Even going lap by lap and looking at the total race time up until that point, I can't figure out Senna's laptime. 

 

1 Lap 1'44.068
2 Laps 4'15.274 (2:30 laptime)
3 Laps 6'49.890 (2:34 lap)
4 Laps 9'26.520 (2:36 lap)
5 Laps 12'01.301 (2:35 lap with Senna first across the line)
6 Laps 13'32.681 (1:32 lap and Schumacher is listed as the leader, with Senna in 22nd on 12'01.301)
 
There was at least one full green flag lap before Senna's accident wasn't there? 

 

 

Yes, there was one lap under green (Senna's last lap). He crashed on his second run through Tamburello after the restart. The lap (Tamburello-Tamburello) is shown in it's entirety on the season review video.



#138 Ross Stonefeld

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Posted 28 February 2014 - 17:03

I just did a self-time on a Youtube clip of the first part of the race, he does at least a sub-1:30, maybe mid 1:20s



#139 rallen

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Posted 28 February 2014 - 17:35

Thank you PCC yes that is what I meant.

 

As we can't know (at least not at the moment) for sure what happend there can be no right or wrong opinion. That is the problem with ambigious situations - it can only be an opinion. Now if you were arguing against fact.... well you can prove anything with facts can't you....

 

Another point that was raised above and stuck in my head - it was suggested Senna made a mistake by entering that corner slightly differently - encountering a bump from the resurface and then going off. How likely do we think this is - no one (in much worse cars and of lesser ability) had this issue in qualify or in the race itself - just (possibly) Senna. Now wasn't one of Senna's strengths that he was like a computer - I am thinking of the a thread I read here a few years ago when he hit a wall in the 80's (Detroit?) and insisted that the wall had moved it wasn't his fault - he dragged his mechanics to it and they found that it had indeed moved by about an inch - another car had perviously hit it displacing the the giant concrete block making up the wall.

 

A lot has focused on mechanical failure - steering break, stall etc - but if we focus on a potential driver error (Damon Hill's theory) how likely is it he would have gone into the corner on a slightly different line? yes Senna made mistakes - all drivers do. I always tend to think of his 'mistakes' as agressive tactics/dirty driving not actually something fundamental as getting a line wrong in a simple corner. So would have have just got the line wrong? would he have been trying to compensate or drive round something on the car? could it have been deliberate (with terrible consequences) such as he thought he might have found a faster or more stable line? or was he distracted by Schumacher behind - but then would he have been concerned to check on Michael at that spot - could Michael have been a threat at that particular spot - wouldn't he have checked before or after the corner?

 

Just thoughts, I appreciate your patience - I have a passion for the sport but I have no technical knowledge or engineering understanding so forgive me if I sound too confused! I just wanted to explore more the possibilities of driver error which tend to get passed over.

 

Personally I think it was a tragic accident with no smoking gun but theres a few things I don't quite understand.


Edited by rallen, 28 February 2014 - 17:36.


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#140 Nemo1965

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Posted 28 February 2014 - 17:57

How do you explain to someone that you can't cure understeer by applying more steering lock??? When it's obvious that the person who's talking doesn't know a thing about the subject he's talking about, every effort to "correct mistakes" is not possible and productive, but futile and a waste of time.

 

Ah, so you are talking about me. Let me see, I wrote: AFAIK, other Indy-drivers have always said that Smiley made the wrong correction: the car oversteered, and Smiley reacted like you would do on a roadcourse: he applied opposite-lock. 

 

That is called 'a strawman', if you deliberately misquote people to undermine what they are saying.

 

Anyways, I am out of this thread. I had an e-mail conversation with a regular poster on the technical forum, an ex-engineer for a F1-team, btw. And he wrote me he did not like to post there because people usually start throwing insults around. I wrote him he was confusing stuff with the racing comments-section.

 

I was wrong.



#141 f1steveuk

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Posted 28 February 2014 - 18:50

I not rude enough not to answer a direct question!

 

Tyre heat. There is always the assumption that tyres warm up by simply going round and round, they don't. They heat up through the various laminate layers acting against each other, so it's all the movements, sideways, slip angle etc that heat a tyre more than simple rotation. The compound (at that time around 95 ingredients) can take two or three laps  to be up to optimum working temperature, which if not all of the various influences acting upon the tyre at a specific time, are also not running at their optimum, there will be a shortfall in performance, i.e grip. If it hits at a time when other aspects of a car are reduced, it might be at that spot between mechanical and aerodynamic grip, e.g, you get neither!!

 

As for the reason the data I was privvy too, it was for internal use within FOM (originally for a camera placement project), so there was, and is, no need for it to available to the public.

 

I don't believe I have been rude to anyone, but frustrated that some people will only see what they want to see, and to dismiss the work of trained engineers, and dismiss studied theories because it doesn't suit, is a bit short sighted (and I don't consider myself in that group), but to be told "oh it can't have been that bumpy" or some such, when I have actually stood there, or spoken to those that designed and built the thing in question, is difficult to understand. I have emailed mzustak directly, which has thrown up something that I had forgotten from my original research, so there is always room to take other facets on board.



#142 David Beard

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Posted 28 February 2014 - 18:57

This thread is going nowhere. Nothing new, except a lot of rudeness.

Can it be moved to RC?



#143 PCC

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Posted 28 February 2014 - 18:59

I don't believe I have been rude to anyone...

And I'm sure no one else believes it either - you are one of TNF's true gentleman, and I mean that sincerely.



#144 David Beard

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Posted 28 February 2014 - 19:15

And I'm sure no one else believes it either - you are one of TNF's true gentleman, and I mean that sincerely.

I didn't mean to accuse Steve of any rudeness,


Edited by David Beard, 28 February 2014 - 19:16.


#145 f1steveuk

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Posted 28 February 2014 - 19:15

And I'm sure no one else believes it either - you are one of TNF's true gentleman, and I mean that sincerely.

Where do I send the cheque Peter!!??  ;)

 

I didn't think you did David

 

I'm going back under my rock now


Edited by f1steveuk, 28 February 2014 - 19:17.


#146 David Beard

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Posted 28 February 2014 - 19:19

This thread is going nowhere. Nothing new, except a lot of rudeness.

Can it be moved to RC?

Or closed? It's rubbish.



#147 kayemod

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Posted 28 February 2014 - 19:26

Or closed? It's rubbish.

 

 

Well, most of it anyway.



#148 PCC

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Posted 28 February 2014 - 19:47

Or closed? It's rubbish.

Well, there is a 100% effective way to remove the irritant of threads you dislike - don't read them!


Edited by PCC, 28 February 2014 - 22:23.


#149 PayasYouRace

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Posted 28 February 2014 - 19:48

 

A lot has focused on mechanical failure - steering break, stall etc - but if we focus on a potential driver error (Damon Hill's theory) how likely is it he would have gone into the corner on a slightly different line? yes Senna made mistakes - all drivers do. I always tend to think of his 'mistakes' as agressive tactics/dirty driving not actually something fundamental as getting a line wrong in a simple corner. So would have have just got the line wrong? would he have been trying to compensate or drive round something on the car? could it have been deliberate (with terrible consequences) such as he thought he might have found a faster or more stable line? or was he distracted by Schumacher behind - but then would he have been concerned to check on Michael at that spot - could Michael have been a threat at that particular spot - wouldn't he have checked before or after the corner?

 

 

For me, it's not about trying to claim that Senna didn't make mistakes, but the nature of Tamburello means that word, "mistake", is too harsh a description of what may have happened. That corner was easy flat, so picking your line wouldn't normally have been so critical a choice. So while it could very well be considered a mistake for Ayrton to have taken that particular line on that particular lap, it must be taken into consideration that it was a mistake compounded by the unusual circumstances and car setup.

 

 

I not rude enough not to answer a direct question!

 

Tyre heat. There is always the assumption that tyres warm up by simply going round and round, they don't. They heat up through the various laminate layers acting against each other, so it's all the movements, sideways, slip angle etc that heat a tyre more than simple rotation. The compound (at that time around 95 ingredients) can take two or three laps  to be up to optimum working temperature, which if not all of the various influences acting upon the tyre at a specific time, are also not running at their optimum, there will be a shortfall in performance, i.e grip. If it hits at a time when other aspects of a car are reduced, it might be at that spot between mechanical and aerodynamic grip, e.g, you get neither!!

 

As for the reason the data I was privvy too, it was for internal use within FOM (originally for a camera placement project), so there was, and is, no need for it to available to the public.

 

I don't believe I have been rude to anyone, but frustrated that some people will only see what they want to see, and to dismiss the work of trained engineers, and dismiss studied theories because it doesn't suit, is a bit short sighted (and I don't consider myself in that group), but to be told "oh it can't have been that bumpy" or some such, when I have actually stood there, or spoken to those that designed and built the thing in question, is difficult to understand. I have emailed mzustak directly, which has thrown up something that I had forgotten from my original research, so there is always room to take other facets on board.

 

I don't want you to take this personally, but I think sometimes you just have to take a step back, and take it from the top. Many here will be encountering this topic for the first time ever, or after a long period of not really thinking about it. We don't all have a full awareness of the case for whatever reason. So what I would say is that if you encounter someone who has suggested a "wrong" version of the story, just explain yourself.

 

Present the facts, what data you can, and when you can't present any data for whatever reason, present an analogous example. Do this and simply explain what you understand to have happened and it will take no longer than writing a post threatening to never post again and that nobody should dismiss anyone's findings because they say so. Instead, explain why their findings are correct. It's a difficult case precisely because a lot of data is not out in the public domain.

 

I do take issue with the way you present mechanical and aerodynamic grip and suggesting there is some sort of gap between the two. I believe I've already explained that a better way to think about it is that aero acts as a multiplier on mechanical grip. But other than that your posts have been very informative and I'd rather not lose you because you're getting a bit frustrated, which happens to all of us on all corners of the internet.



#150 rallen

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Posted 28 February 2014 - 20:22

I have been away from this site for a over a year and the first thread I comment on someone asked for it to be closed. This site used to be brilliant. 

 

David Beard, I respectfully ask that you stop reading this thread if you find it not to your taste and stop dictating to others what they can and can't read. I don't read threads about people looking for for someone they used to know in the 60's.

 

Right back on topic, thanks for your replies Stevef1 & Payasyourace. It would be interesting how close Senna came to that particular line in qualifying or the pervious laps. Indeed did he actually take a slightly different line or is this just a theory? - I realised I was making it sound like he was taking a different line. Any evidence to support this? if he took the same line as he always did then that would make the driver error theory be viewed slightly differently?