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The Mickey Thompson 'Sears Allstate Special' cars of 1964


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#1551 R.W. Mackenzie

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Posted 05 September 2011 - 01:43

Don't know if this has ever been discussed before. On Historic Mustang's site he has an article that goes into great detail about the crash:

http://www.historicm...chsIndianapolis

"In the midst of the confusion and the few microseconds allowed for correction another car vaulted over the top and stopped Thompson's car in its tracks. Meanwhile Sachs was exiting the turn when the flaming car appeared in front of his path at an estimated 160 mph! Race driver logic to put a wreck behind you came into play - he steered towards the ball of fire, estimating he would clear it by the time he reached the spot. But when the roadster clambered over the fireball, it stopped in its track. Eddie's plan was all wrong. He struck the flaming car square in the burning fuel tank spraying flaming high octane gasoline all over the Shrike. The impact welded the two cars together and they slid to a stop about 40 yards from the point of impact."

Hurtubise, Hansgen, Branson, Sutton, Rathmann and Veith were the last cars to clear the scene before Sachs, Rutherford, Duman and Unser arrived. Rathmann was driving the only roadster that could have hit or gone over MacDonald before Sachs hit him. But I have viewed the various videos over and over and don't see any evidence that any car hit MacDonald before Sachs did.

Am I missing something?

Bob Mackenzie



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#1552 Lemnpiper

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Posted 05 September 2011 - 02:39



Hello Bob


One thing that has never gotten much print is if the thompson left a trail of marks in the dirt and asphalt as it slid away from the wall back onto the track.

My theory is something on the bottom of the car was dragging so severely that it acted like an anchor thereby slowing the thompson til it caused it being stopped in the path of Sachs when Sachs thought it would continue to keep sliding.( just a theory at this point though if i missed a discussion i am more than will to accept their findings)

Paul

#1553 HistoricMustang

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Posted 05 September 2011 - 07:57

Hello Bob


One thing that has never gotten much print is if the thompson left a trail of marks in the dirt and asphalt as it slid away from the wall back onto the track.

My theory is something on the bottom of the car was dragging so severely that it acted like an anchor thereby slowing the thompson til it caused it being stopped in the path of Sachs when Sachs thought it would continue to keep sliding.( just a theory at this point though if i missed a discussion i am more than will to accept their findings)

Paul


Hi Paul,
From the Alternate (permission granted) an account of the scene from an individual who was actually there and with a somewhat unbiased view.

Ironic that the author, as so many do, misspelled Dave's name.

Posted Image

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Most TNF members have spent time studying this accident, some for hours and some of us for days. In my case it has been years.

The conclusions reached in the thread seem to be extremely accurate. However, there are some disagreements on what triggered the horrible chain of events leading up to the actual spin of the MacDonald car.





#1554 Henri Greuter

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Posted 05 September 2011 - 14:25

You dont give me credit that maybe I did read this entire thread..That is beside the point..If you break the video of the impact with the wall down frame by frame you will see that imediately upon impact a white substance shoots straight into the air..Now at first I considered it may have been concrete dust from the hard impact with the wall..But concrete dust does not ignite into a fireball..Also yes the left side tank did break at 2 points..Out the left rear of the car and the fuel nozzle..It did ignite first at the rear of the vehicle probably due to the hot exhaust...But imediately engulfed the entire vehicle, probably due to the tank nozzle breach..However the intial cloud which by now is several feet in the air also ignited..So in my opinion there COULD have been some fuel on the right side..after all, we all are entitled to are opinions..




Tom,

Have a look on this interenet site, it is an article printed in Sports Illustrated as early as Summer 1964.

http://sportsillustr...76051/index.htm


The one paramount line of importance is:


First of all, Mickey Thompson, builder of MacDonald's Ford-engined car, scotched an Associated Press story estimating the gasoline load at a fantastic 100 gallons (some 600 pounds in a car weighing about 1,200 dry). "We carried 45 gallons," said Thompson, a fact verified by Ray McMahan, the chief Mobil fuel specialist at Indy. Thompson said the gas was in a single rubber tank extending most of the distance between the front and rear wheels on the driver's left



Personally, I don't think that the 1 or 2 gallons differences between what Thompson said and this official confirms and/or what Bryant told is a significicant difference that must be the missing gallon or two that must have been stored in a right side tank that you believe there must have been after all.

One of the things with this accident is indeed that the sea of fire that burst out is credited to have been the result of two cars carrying 100 gallons of fuel. But it is downright impossible that the Shrike could have contained 100 gallons and still accomodate Sachs too. I've seen the replica of the car and I've seen the volume of 100 gallon.
The article I quoted from and gave the link for is one of the best examples of how much facts and date were ignored in the aftermath of the accident. Simply because just about everyone unloaded on MacDonald, based on the things he had said about the car being unstable and the othere approvals of the car bing difficult to drive. Then, it did appear in print that Thompson wanted to fit the car with extra fuel tanks to go non-stop because of the good tire wear he got. (I think he failed to realize that his car had so less grip that it had virtually no tire wear to begin with...) Nobody of the press ever cared to verify if Micke did indeed do what he said he wanted to do and had it printed as a follow up on the first story.

But after the accident, there was simply few, if any journalist willing to take an unbiased look on Mickey T and Dave anymore after the horror scenes they saw. The common approach was: get over it, put the blame on Dave, he's dead anyway so he doen't have to carry the burden either. But this Sports Illustrated article, published already in 1964 (!!!) simply approves that evidence and statements that lead to something else then two 100 gallon cars bursting open were ignored because that sea of Fire simply had to be fed by so much fuel.

Well, thank God it took much less then that. because also ignored all those years was that the Shrike still contained at least 2/3 of its fuel capacity.
if it really had been two 100 gallon cars that had lost their entire fuel contents, then I fear that there had been fatalities in the crowd as well and I wonder if Tony Hulman would have continued with the 500 had paying spectators being killed on his property. Drivers being killed was one thing, spectators, now that was something else.


I must look on the videos to see about that original cloud as you describe that went ablaze too. I agree, Paint or concrete won't burn. But the evidence and reports simply exlude a right side fuel tank for 99.9 %. So what it is? Perhaps a fuel line on the inlets on that right side of the car came lose ans spewed fuel in the air? That's about all I can think of that maybe could cause it.


Henri

Edited by Henri Greuter, 05 September 2011 - 14:34.


#1555 Michael Ferner

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Posted 05 September 2011 - 14:38

Don't know if this has ever been discussed before. On Historic Mustang's site he has an article that goes into great detail about the crash:

http://www.historicm...chsIndianapolis

"In the midst of the confusion and the few microseconds allowed for correction another car vaulted over the top and stopped Thompson's car in its tracks. Meanwhile Sachs was exiting the turn when the flaming car appeared in front of his path at an estimated 160 mph! Race driver logic to put a wreck behind you came into play - he steered towards the ball of fire, estimating he would clear it by the time he reached the spot. But when the roadster clambered over the fireball, it stopped in its track. Eddie's plan was all wrong. He struck the flaming car square in the burning fuel tank spraying flaming high octane gasoline all over the Shrike. The impact welded the two cars together and they slid to a stop about 40 yards from the point of impact."

Hurtubise, Hansgen, Branson, Sutton, Rathmann and Veith were the last cars to clear the scene before Sachs, Rutherford, Duman and Unser arrived. Rathmann was driving the only roadster that could have hit or gone over MacDonald before Sachs hit him. But I have viewed the various videos over and over and don't see any evidence that any car hit MacDonald before Sachs did.

Am I missing something?

Bob Mackenzie


No, you didn't miss anything - but the author of those lines got it wrong, and twice at that.

1) The car that ran "over the top" of the Thompson was Rutherford's Watson, and it happened after Sachs hit MacDonald.

2) Sachs did not steer towards the "ball of fire", as in "race driver logic" - if he had, he'd probably have escaped the wreck.

There seems to be a fundamental misunderstanding of the "race driver logic" that says: "If you see a wreck happening in front of you, steer towards it and you will clear it". Sachs spotted the wreck when coming out of Turn 4, and steering towards it would have meant going to the INSIDE (LEFT) of the track - because THAT'S where the wreck was happening when Sachs first spotted it, and THAT'S what's meant by the "race driver logic"!!! It's important for a racing driver to drill your instincts to react the right way when confronted with such a situation, and I'm sure that with twenty years of experience, Sachs was well prepared - unfortunately, other instincts come into play here, like "Avoid a situation where you can't see where you're going!", and "Avoid FIRE!!", which adds up to: "BY ALL MEANS, AVOID RUNNING INTO A HUGE WALL OF FIRE AND SMOKE!!!!" Evidently, the second instinct is much, much stronger than the "steer towards the wreck" instinct, as apart from Sachs, every other driver in that train of cars reacted exactly the same, namely the wrong way. [speculation] If all drivers had gone to the left/inside of the track ("steering towards the wreck"), the Thompson would've likely hit the outer wall at a shallow angle, and slid along it for a few more feet, keeping well clear of the path of the oncoming cars, which would've all made it safely through the wall of fire, a burnt whisker or some blistered paint notwithstanding. [/speculation]

#1556 TomSlick57

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Posted 05 September 2011 - 16:07

Tom,

Have a look on this interenet site, it is an article printed in Sports Illustrated as early as Summer 1964.

http://sportsillustr...76051/index.htm


The one paramount line of importance is:


First of all, Mickey Thompson, builder of MacDonald's Ford-engined car, scotched an Associated Press story estimating the gasoline load at a fantastic 100 gallons (some 600 pounds in a car weighing about 1,200 dry). "We carried 45 gallons," said Thompson, a fact verified by Ray McMahan, the chief Mobil fuel specialist at Indy. Thompson said the gas was in a single rubber tank extending most of the distance between the front and rear wheels on the driver's left



Personally, I don't think that the 1 or 2 gallons differences between what Thompson said and this official confirms and/or what Bryant told is a significicant difference that must be the missing gallon or two that must have been stored in a right side tank that you believe there must have been after all.

One of the things with this accident is indeed that the sea of fire that burst out is credited to have been the result of two cars carrying 100 gallons of fuel. But it is downright impossible that the Shrike could have contained 100 gallons and still accomodate Sachs too. I've seen the replica of the car and I've seen the volume of 100 gallon.
The article I quoted from and gave the link for is one of the best examples of how much facts and date were ignored in the aftermath of the accident. Simply because just about everyone unloaded on MacDonald, based on the things he had said about the car being unstable and the othere approvals of the car bing difficult to drive. Then, it did appear in print that Thompson wanted to fit the car with extra fuel tanks to go non-stop because of the good tire wear he got. (I think he failed to realize that his car had so less grip that it had virtually no tire wear to begin with...) Nobody of the press ever cared to verify if Micke did indeed do what he said he wanted to do and had it printed as a follow up on the first story.

But after the accident, there was simply few, if any journalist willing to take an unbiased look on Mickey T and Dave anymore after the horror scenes they saw. The common approach was: get over it, put the blame on Dave, he's dead anyway so he doen't have to carry the burden either. But this Sports Illustrated article, published already in 1964 (!!!) simply approves that evidence and statements that lead to something else then two 100 gallon cars bursting open were ignored because that sea of Fire simply had to be fed by so much fuel.

Well, thank God it took much less then that. because also ignored all those years was that the Shrike still contained at least 2/3 of its fuel capacity.
if it really had been two 100 gallon cars that had lost their entire fuel contents, then I fear that there had been fatalities in the crowd as well and I wonder if Tony Hulman would have continued with the 500 had paying spectators being killed on his property. Drivers being killed was one thing, spectators, now that was something else.


I must look on the videos to see about that original cloud as you describe that went ablaze too. I agree, Paint or concrete won't burn. But the evidence and reports simply exlude a right side fuel tank for 99.9 %. So what it is? Perhaps a fuel line on the inlets on that right side of the car came lose ans spewed fuel in the air? That's about all I can think of that maybe could cause it.


Henri

Great information and insight a usual Henri, In over 50 years of involmant in motorsports in the United States (Short tracks, Modifieds and Late Models), The one constant I have seen is that a Car owner ,Driver, or Crew chief will do anything and say anything to get and edge on the competition..Now I have been a bit chastised on here for not having any facts, Well my previous statemant is a fact..And example of this I experienced last night at labor day modified 100 lap high paying event in Central NY state..Juicing of tires to obtain better grip (making the compound softer) is major problem the last few years in this sport..A car can be over a second or more faster on a half mile track by doing this..Obviously its a huge advantage..So tracks (like this one) decided to stop the winning car on the back straight and check tires before he even made it back to victory lane..Good idea...What they didnt anticapate was the driver purposely spinning his car thru turn #2, thru the wet grass to cool his tires..My point is simply anything is possible..Now to your points which i totally agree with..No I do not believe there was some 100 gallons of fuel..45 Gallons is more then enough to obtain that amount of flame.I am not suggesting there was a right side fuel tank either..But I wont dismiss the fact that a team will do anyhing to have and edge to win a big race..Having a gallon or possibly two in reserve that could be tapped into for maybe that extra lap at the end of the race..or for extra right side weight for balance..All I'm saying Herni is the truth is very often never known..These car owners drivers and crew chiefs would literally take it to there graves.

#1557 Lemnpiper

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Posted 06 September 2011 - 00:11

I am not suggesting there was a right side fuel tank either..But I wont dismiss the fact that a team will do anyhing to have and edge to win a big race..Having a gallon or possibly two in reserve that could be tapped into for maybe that extra lap at the end of the race..or for extra right side weight for balance..All I'm saying Herni is the truth is very often never known..These car owners drivers and crew chiefs would literally take it to there graves.



Tom ,

Was Mickey Thompson as a car constructor as "creative" as Smokey Yunick in circumventing the rules?

Because if Dave's car had been built by Smokey i could see it having hidden gas in places the officials wouldnt know to look for.


Another reason some in charge may have wanted to place so much of the blame on Dave & Mickey as fast a possible , was to keep blame from being placed on the folks that had made Mickey modify the car so much during month prior to the race , which in fact may have added to the handling issues .


Paul

#1558 Henri Greuter

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Posted 06 September 2011 - 07:20

[quote name='TomSlick57' post='5263352' date='Sep 5 2011, 16:07']But I wont dismiss the fact that a team will do anyhing to have and edge to win a big race..Having a gallon or possibly two in reserve that could be tapped into for maybe that extra lap at the end of the race..or for extra right side weight for balance..All I'm saying Herni is the truth is very often never known..These car owners drivers and crew chiefs would literally take it to there graves.[/quote]


Thanks for your comments Tom, I see your points and indeed, I'm sure there are secrets still to be discovered.
A little tank with some gallons on the right for just in case, yes, that could be possible. But I don't think that the handling of the car was a reason to add a few gallons to the right side pod. Certainly in the 60's left side weight bias was common on the speedway so why offset it? With only a 15 or so pounds? But a little for just in case....
But I don't know if this is in the line of thinking you would expect from Mickey Thompson.
Also because from what I found out about him, I think that Pete Bryant would be more that open and honest enough to have mentioned such in his book, should he have known about it,


[quote] Tom ,

Was Mickey Thompson as a car constructor as "creative" as Smokey Yunick in circumventing the rules?

Because if Dave's car had been built by Smokey i could see it having hidden gas in places the officials wouldnt know to look for.


Another reason some in charge may have wanted to place so much of the blame on Dave & Mickey as fast a possible , was to keep blame from being placed on the folks that had made Mickey modify the car so much during month prior to the race , which in fact may have added to the handling issues .


Paul

[\quote]


Also an interesting point to consider. That ban on the little wheels...
On the other hand, it came in time and as far as I can recall (must look that up) , there was some testing being done with the car on the 15 inch wheels already so the team was aware of having problems before may but not done much about it yet. If indeed true that they did test with the 15 inchers before May.
But I think the handling of the car was compromised by other things too. I mentioned that already before but I wonder what effects the cnage of pushrod Chevy V8 to Ford Quadcam had. The Ford was much more top heavy, had a higher GC then the Chevy. While I don't know what the weight difference betwseen the two engines was, i would not be at all surprised if the Ford was also more heavy then the Chevy, thus changing the overall GC of the entire car massively.

Henri

Henri


#1559 ZOOOM

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Posted 06 September 2011 - 14:22

Think back to those days... The roadsters were regularly toting 100 gallons of methanol around. There was no upper limit on fuel. There would have been no reason for Thompson to "hide" a second on the right side. It would have been perfectly legal.
He would have had a choice of designs for the tank of course, bladder or solid aluminum... Either one would have required a LOT of fabrication to get it to fit on the right side of the car. IIRC, they spent a LOT of time in practise just getting the car to handle on it's own without the additional problem of installing a perfectly legal tank on the right sidepod.
It didn't happen...

ZOOOM

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#1560 TomSlick57

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Posted 06 September 2011 - 14:37

Tom ,

Was Mickey Thompson as a car constructor as "creative" as Smokey Yunick in circumventing the rules?

Because if Dave's car had been built by Smokey i could see it having hidden gas in places the officials wouldnt know to look for.


Another reason some in charge may have wanted to place so much of the blame on Dave & Mickey as fast a possible , was to keep blame from being placed on the folks that had made Mickey modify the car so much during month prior to the race , which in fact may have added to the handling issues .


Paul

Paul, Being that Mickey pursued and I believe held the land speed record at one point..Yes I do think he was and equal to Smokey..Also in 1964 he did get 2 of his cars in the field where as Yunicks offset failed to make it..But you also have to consider that Thompson did have a huge advantage with the new Ford Engines..You do bring up a good point about all the changes he was forced to make to his cars..I'm sure it definately added to the cars handling woes

#1561 TomSlick57

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Posted 06 September 2011 - 14:45

Think back to those days... The roadsters were regularly toting 100 gallons of methanol around. There was no upper limit on fuel. There would have been no reason for Thompson to "hide" a second on the right side. It would have been perfectly legal.
He would have had a choice of designs for the tank of course, bladder or solid aluminum... Either one would have required a LOT of fabrication to get it to fit on the right side of the car. IIRC, they spent a LOT of time in practise just getting the car to handle on it's own without the additional problem of installing a perfectly legal tank on the right sidepod.
It didn't happen...

ZOOOM

Well Zooom If that is true (which i wasnt aware of) and you could run and unlimited amount of fuel..Then no there would be no need to hide any which basically was my thinking..I still am concerned in the video of the impact with the wall where it appears that liquid sprays straight up at the moment of impact, just seems to quick to have come from the left side..That is what got me on this thinking in the first place

Edited by TomSlick57, 06 September 2011 - 15:04.


#1562 TomSlick57

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Posted 06 September 2011 - 15:03

But I don't know if this is in the line of thinking you would expect from Mickey Thompson.
Also because from what I found out about him, I think that Pete Bryant would be more that open and honest enough to have mentioned such in his book, should he have known about it,


Henri,
I was under the impression that Mickey could be the type of person to consider the unexpected..Though I didnt know the man I had the honor of meeting him in California in the early 80's..Had I known then of his pending untimely murder, I would have asked him at the risk of pissing him off about a couple items of interest..But then again it wasnt the right time nor my place to bring up anything to do with this topic.

#1563 Henri Greuter

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Posted 06 September 2011 - 15:22

But I don't know if this is in the line of thinking you would expect from Mickey Thompson.
Also because from what I found out about him, I think that Pete Bryant would be more that open and honest enough to have mentioned such in his book, should he have known about it,


Henri,
I was under the impression that Mickey could be the type of person to consider the unexpected..Though I didnt know the man I had the honor of meeting him in California in the early 80's..Had I known then of his pending untimely murder, I would have asked him at the risk of pissing him off about a couple items of interest..But then again it wasnt the right time nor my place to bring up anything to do with this topic.





Tom,

I'll be the first one to admit that I have been outspoken negative about Mickey too. But also because of this thread I found out more about him and nowadays I feel that he gets too less credit for his achievements at Indy before 1964. Much loathed Mickey was the first Anmerican car builder who saw the light that the rear engine car was the way to go, even before Chapman and Lotus arrived.
Perhaps he didn't do it the right way, but he was ahead of the man credited with starting the RE revolution seriously (Chapman) with bringing RE cars.
Fortunately that 1962 car of him is on display at IMS but it deserves more credit for Mickey in addition to being Gurney's rookie ride.


By the way, keep posting and suggesting, you bring up interesting points and I enjoy exchanging thoughts and facts with you.

henri



#1564 HistoricMustang

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Posted 06 September 2011 - 17:41

In my opinion this photograph shows an actual delay of the fuel "explosion" which did not happen upon wall impact.

To me it indicates ample time after the impact for at least a partial fuel load flash.

The fuel cap, they were not locked in those days, popped open permitting enough fuel and vapor to escape to begin the chain reaction.

The initial small flames were behind the wall and not seen by most. Therefore, most people identify the large explosion with initial wall impact. It was not.

Of course a second "explosion" occured with an impact by the Sachs vehicle.

Henry

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#1565 thatguy0101

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Posted 08 September 2011 - 17:48

Another reason some in charge may have wanted to place so much of the blame on Dave & Mickey as fast a possible , was to keep blame from being placed on the folks that had made Mickey modify the car so much during month prior to the race , which in fact may have added to the handling issues .


Based on Peter Bryant's book, USAC didn't demand any mods during the month. The significant change from 1963 that USAC imposed was well before the race, when they mandated a minimum 15" wheel diameter. Mickey had the wheels and tires made before May, and they fitted inside the full bodywork that was on the car when it arrived in Indianapolis. The bodywork was cut away to reduce lift, not to fit bigger tires that were suddenly forced on Thompson at IMS. The suspension geometry was significantly modified by the Thompson team before pole qualifying, because the handling was scary and uncompetitive. Bryant claims that the modified car was then generally competitive and stable.

Edited by thatguy0101, 08 September 2011 - 17:58.


#1566 Doug Nye

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Posted 08 September 2011 - 18:28

In my opinion this photograph shows an actual delay of the fuel "explosion" which did not happen upon wall impact.

To me it indicates ample time after the impact for at least a partial fuel load flash.

The fuel cap, they were not locked in those days, popped open permitting enough fuel and vapor to escape to begin the chain reaction.

The initial small flames were behind the wall and not seen by most. Therefore, most people identify the large explosion with initial wall impact. It was not.

Of course a second "explosion" occured with an impact by the Sachs vehicle.

Henry

Posted Image


Just one note of caution here - it would have taken some time for the fireball to collapse and combustion to have produced such a volume of dense smoke as captured in that photo. This freezes a moment some appreciable moments after the initial impact, as you say, but it does not - surely - show the 'fuel explosion' to which you refer. Does it?

DCN

#1567 HistoricMustang

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Posted 08 September 2011 - 19:37

Just one note of caution here - it would have taken some time for the fireball to collapse and combustion to have produced such a volume of dense smoke as captured in that photo. This freezes a moment some appreciable moments after the initial impact, as you say, but it does not - surely - show the 'fuel explosion' to which you refer. Does it?

DCN


Hi Doug,
I was only trying to say that the large fireball did not occur at the initial wall impact. My apology if misunderstood.

Of course this is only my opinion but there does appear to be fire along wall and in grass before the large "explosion" actually took place.

Henry :wave:

#1568 TomSlick57

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Posted 08 September 2011 - 22:50

Based on Peter Bryant's book, USAC didn't demand any mods during the month. The significant change from 1963 that USAC imposed was well before the race, when they mandated a minimum 15" wheel diameter. Mickey had the wheels and tires made before May, and they fitted inside the full bodywork that was on the car when it arrived in Indianapolis. The bodywork was cut away to reduce lift, not to fit bigger tires that were suddenly forced on Thompson at IMS. The suspension geometry was significantly modified by the Thompson team before pole qualifying, because the handling was scary and uncompetitive. Bryant claims that the modified car was then generally competitive and stable.

I always thought they cut away the front fenders because this was and is and open wheel divison...And as far as the fireball the car hit slid maybe 2 or 3 feet..when the left side tank blew out at the rear of the car..Then it ignited into that fireball..from what ive seen in a frame by frame search is the fuel cap also popped and forced fuel over the entire car..but it appears the rear of the vehicle was the source of the ignition..But the intial hit with the wall also caused a spray which also ignited..that is what i saw

Edited by TomSlick57, 08 September 2011 - 22:58.


#1569 R.W. Mackenzie

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Posted 09 September 2011 - 02:00

I have always found the 1964 Indy 500 to be a fascinating topic. Of all the threads on this forum this is the one I watch most closely. I only dive in when I feel I have something to contribute.

While I was reviewing today's posts it occurred to me that while we have heard from most of the participants we haven't heard from all of them and I thought I would check to see how many of the participants in this race were still alive. Unfortunately the answer is that not many of them are still with us. Of the 33 starters only 9 are still alive. Rows two and nine are particularly blessed as the occupants of these two rows are still with us. (As are single occupants of rows 5, 8 and 10.)

The following is a row by row summary listing either their date of passing or the fact that they are still with us:

Jim Clark - April 7, 1968
Bobby Marshman - December 4, 1964
Roger Ward - July 5, 2004

Parnelli Jones - Alive and kicking!
A.J. Foyt - Alive and kicking!
Dan Gurney - Alive and kicking!

Lloyd Ruby - March 23, 2009
Len Sutton - December 4, 2006
Don Branson - November 12, 1966

Walt Hansgen - April 7, 1966
Jim Hurtubise - January 6, 1989
Dick Rathmann - February 1, 2000

Johnny Boyd - October 27, 2003
Eddie Sachs - May 30, 1964
Johnny Rutherford - Alive and kicking!

Ronnie Duman - June 9, 1968
Dave MacDonald - May 30, 1964
Troy Ruttman - May 19, 1997

Bud Tingelstad - July 30, 1981
Bobby Grim - June 14, 1995
Johnny White - December 24, 1977

Bobby Unser - Alive and kicking!
Bob Veith - March 29, 2006
Eddie Johnson - June 30, 1974

Jack Brabham - Alive and kicking!
Jim McElreath - Alive and kicking!
Bob Harkey - Alive and kicking!

Bob Mathouser - November 15, 1980
Chuck Stevenson - August 21, 1995
Art Malone - Alive and kicking!

Norm Hall - March 11, 1992
Bob Wente - August 13, 2000
Bill Cheesbourg - November 6, 1995

Regards,

Bob Mackenzie

#1570 HistoricMustang

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Posted 09 September 2011 - 12:57

I have always found the 1964 Indy 500 to be a fascinating topic. Of all the threads on this forum this is the one I watch most closely. I only dive in when I feel I have something to contribute.

While I was reviewing today's posts it occurred to me that while we have heard from most of the participants we haven't heard from all of them and I thought I would check to see how many of the participants in this race were still alive. Unfortunately the answer is that not many of them are still with us. Of the 33 starters only 9 are still alive. Rows two and nine are particularly blessed as the occupants of these two rows are still with us. (As are single occupants of rows 5, 8 and 10.)

The following is a row by row summary listing either their date of passing or the fact that they are still with us:

Jim Clark - April 7, 1968
Bobby Marshman - December 4, 1964
Roger Ward - July 5, 2004

Parnelli Jones - Alive and kicking!
A.J. Foyt - Alive and kicking!
Dan Gurney - Alive and kicking!

Lloyd Ruby - March 23, 2009
Len Sutton - December 4, 2006
Don Branson - November 12, 1966

Walt Hansgen - April 7, 1966
Jim Hurtubise - January 6, 1989
Dick Rathmann - February 1, 2000

Johnny Boyd - October 27, 2003
Eddie Sachs - May 30, 1964
Johnny Rutherford - Alive and kicking!

Ronnie Duman - June 9, 1968
Dave MacDonald - May 30, 1964
Troy Ruttman - May 19, 1997

Bud Tingelstad - July 30, 1981
Bobby Grim - June 14, 1995
Johnny White - December 24, 1977

Bobby Unser - Alive and kicking!
Bob Veith - March 29, 2006
Eddie Johnson - June 30, 1974

Jack Brabham - Alive and kicking!
Jim McElreath - Alive and kicking!
Bob Harkey - Alive and kicking!

Bob Mathouser - November 15, 1980
Chuck Stevenson - August 21, 1995
Art Malone - Alive and kicking!

Norm Hall - March 11, 1992
Bob Wente - August 13, 2000
Bill Cheesbourg - November 6, 1995

Regards,

Bob Mackenzie



Bob, great information.

Dan and Dave were good friends. Does anyone recall Dan Gurney making any statements about that day at Indy?

My apologies if I have forgotten his views are buried in this thread.

#1571 Michael Ferner

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Posted 09 September 2011 - 16:00

In my opinion this photograph shows an actual delay of the fuel "explosion" which did not happen upon wall impact.

Posted Image


... and the picture also illustrates very well what is meant by "steering towards the wreck", and WHY nobody did it!

Thanks for posting! :)

#1572 R.W. Mackenzie

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Posted 10 September 2011 - 16:15

Apparently there was an event back on May 26, 2011 inducting a number of drivers into the Indy Hall of Fame.

The picture below shows a group of former drivers in attendance:

Posted Image

The drivers included 7 of the 9 living 1964 qualifiers I listed above:

Art Malone (second from left)
Johnny Rutherford (fourth from left)
Bob Harkey (fourth from right)
Bobby Unser (third from right)
Parnelli Jones (second from)
Jim McElreath (far right)
Dan Gurney (not in picture)

It appears A.J. Foyt and Jack Brabham were the only survivors missing from the event.

This is the link to the article about the event:

http://www.racingnat...ry.asp?aid=1985

I came upon this while I was looking for info on Art Malone. I'm not sure if his account of the accident has ever been published. Also I'm curious as to why he dropped back to dead last at the start.

Any of our Novi experts know?

Bob Mackenzie

Edited by R.W. Mackenzie, 10 September 2011 - 16:16.


#1573 Jim Thurman

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Posted 10 September 2011 - 16:31

And since some here, and even more so on another forum, like to make a huge deal of the mortality rate, 7 of the 33 drivers died in racing accidents, and all but 1 of the rest has been natural causes.

#1574 ensign14

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Posted 10 September 2011 - 19:21

Positively benign, compared to the 1955 event...

#1575 Lemnpiper

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Posted 10 September 2011 - 20:17

[quote name='R.W. Mackenzie' date='Sep 10 2011, 12:15' post='5272786']
Apparently there was an event back on May 26, 2011 inducting a number of drivers into the Indy Hall of Fame.

The picture below shows a group of former drivers in attendance:

Posted Image

The drivers included 7 of the 9 living 1964 qualifiers I listed above:

Art Malone (second from left)
Johnny Rutherford (fourth from left)
Bob Harkey (fourth from right)
Bobby Unser (third from right)
Parnelli Jones (second from)
Jim McElreath (far right)
Dan Gurney (not in picture)

It appears A.J. Foyt and Jack Brabham were the only survivors missing from the event.

For the record thats Don Edmunds (far left) and Paul Goldsmith (3rd from left) with Chuck Hulse between Rutherford & Harkey

Goldsmith looks great for someone nearly 86 btw


Paul

Edited by Lemnpiper, 29 September 2011 - 01:21.


#1576 TomSlick57

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Posted 28 September 2011 - 01:46

Posted Image

#1577 ZOOOM

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Posted 28 September 2011 - 16:01

I came upon this while I was looking for info on Art Malone. I'm not sure if his account of the accident has ever been published. Also I'm curious as to why he dropped back to dead last at the start.

Any of our Novi experts know?


In Granatelli's book he says that the pace of the start was so slow that Malone had to slip the clutch in low gear to keep up and keep the engine clean. This eventually froze the clutch and kept the car in low gear and was the end of his day. They couldn't get the gearbox to go into high gear...
So says Andy...

ZOOOM

#1578 R.W. Mackenzie

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Posted 28 September 2011 - 21:27

Thanks Zooom

Bob Mackenzie

Edited by R.W. Mackenzie, 28 September 2011 - 21:28.


#1579 HistoricMustang

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Posted 29 September 2011 - 16:34

Yes, thanks Zooom! :wave:

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#1580 Henri Greuter

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Posted 30 September 2011 - 06:21

I came upon this while I was looking for info on Art Malone. I'm not sure if his account of the accident has ever been published. Also I'm curious as to why he dropped back to dead last at the start.

Any of our Novi experts know?


In Granatelli's book he says that the pace of the start was so slow that Malone had to slip the clutch in low gear to keep up and keep the engine clean. This eventually froze the clutch and kept the car in low gear and was the end of his day. They couldn't get the gearbox to go into high gear...
So says Andy...

ZOOOM




Zoom, this was about 1963, when Art drove the high finned job #75.

Personally, I don't know if Art ever spoke about the Sachs-MacDonald accident. The only thing I can recall out of the top of my head what George Peters and I mentioned in our Novi Vol 2 about Art and the accident is that the brakes on his car were very weak and that he narrowly avoided coming to a standstill without ending up in a fire too.
George did the interview with Art that we used for the book. I only met Art for the first ever time last May, the day before the race and way too brielfy to my liking. I could have talked for hours with him had I got the chance.
It is beyond the topic but Art's drive in the Novi that year, how he made the field and all is stuff of legends and very underrated. The bare fact that he qualified that car was a miracle in itself.
Pity that he is mostly rememberd for driving that outrageous looking high finnned #75 and had a rotten race in it too. His 1964 performance is much more impressive and, as said, terribly underrated.


Henri

Edited by Henri Greuter, 30 September 2011 - 06:24.


#1581 R.W. Mackenzie

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Posted 12 October 2011 - 20:46

I continue to research the topic of the 1964 Indy 500 and I've come across with a couple of issues.

First of all, several cars qualified in a form different from how they raced. Four examples are:

1. Roger Ward qualified with his right side fuel tank removed.

2. Parnelli Jones qualified with aerodynamic hub caps.

3. Johnny Rutherford practiced and qualified with a purple and black paint scheme and raced painted yellow.

4. A.J. Foyt had an external oil tank during practice and qualifying yet removed it for the race.

The first three are understandable. Ward and Jones were looking for a speed advantage and Rutherford presumably had a sponsorship change. However, it makes no sense that Foyt would have dragged an external oil tank around for qualifying and removed it for the race.

So I have two questions:

1. Who else took such measures during qualifying?

2. Why did Foyt take his external oil tank off for the race?

Secondly, both Foyt and Jones had rear engined cars available to them in practice and qualifying. Foyt's was one of the Huffaker cars that was driven by Bob Veith in the race. Parnelli had a car numbered 97 but I don't know who built it. It looked somewhat like the car that Dempsey Wilson drove but didn't qualify.

My question is, who built the rear engined car #97 that Parnelli Jones had at his disposal?

Bob Mackenzie

#1582 ovfi

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Posted 12 October 2011 - 20:55

I continue to research the topic of the 1964 Indy 500 and I've come across with a couple of issues.

First of all, several cars qualified in a form different from how they raced. Four examples are:

1. Roger Ward qualified with his right side fuel tank removed.

2. Parnelli Jones qualified with aerodynamic hub caps.

3. Johnny Rutherford practiced and qualified with a purple and black paint scheme and raced painted yellow.

4. A.J. Foyt had an external oil tank during practice and qualifying yet removed it for the race.

The first three are understandable. Ward and Jones were looking for a speed advantage and Rutherford presumably had a sponsorship change. However, it makes no sense that Foyt would have dragged an external oil tank around for qualifying and removed it for the race.

So I have two questions:

1. Who else took such measures during qualifying?

2. Why did Foyt take his external oil tank off for the race?

Secondly, both Foyt and Jones had rear engined cars available to them in practice and qualifying. Foyt's was one of the Huffaker cars that was driven by Bob Veith in the race. Parnelli had a car numbered 97 but I don't know who built it. It looked somewhat like the car that Dempsey Wilson drove but didn't qualify.

My question is, who built the rear engined car #97 that Parnelli Jones had at his disposal?

Bob Mackenzie

Bob, the rear engined car 97 was built by Troutman & Barnes.

#1583 HistoricMustang

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Posted 12 October 2011 - 21:42

This thread contains a tremendous amount of information on the Mickey Thompson effort at Indy in 1964 and the unfortunate accident as well as additional information about that particular race.

I have no objection to modifying the thread to include the entire 1964 event.

Perhaps "The Mickey Thompson 'Sears Allstate Special' and Indy 1964"

The information about pre-race and race modifications intrigues me.

Should we keep the thread pure with most information concerning the accident or expand?

Opinions please!

Henry :wave:

#1584 D-Type

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Posted 12 October 2011 - 22:05

It's a classic case of asking a moderator to split the thread post by post to create two thread and name them appropriately. If
(a) the software allows it, and
(b) either David or Twinny is prepared to take the time to plough through nearly 1600 posts

On the other hand, I don't like the idea of a thread devoted solely to picking over the bones of a single fatal accident.

#1585 bill p

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Posted 13 October 2011 - 07:35

This thread contains a tremendous amount of information on the Mickey Thompson effort at Indy in 1964 and the unfortunate accident as well as additional information about that particular race.

I have no objection to modifying the thread to include the entire 1964 event.

Perhaps "The Mickey Thompson 'Sears Allstate Special' and Indy 1964"

The information about pre-race and race modifications intrigues me.

Should we keep the thread pure with most information concerning the accident or expand?

Opinions please!

Henry :wave:


Please split the thread now as the more general discussions merit their own thread


#1586 Manfred Cubenoggin

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Posted 13 October 2011 - 10:34

Let the thread run as is. Deviations from the topic are the norm here at TNF.



#1587 R.W. Mackenzie

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Posted 13 October 2011 - 11:14

I didn't intend to create a schism! :drunk:

My post was slightly off topic but intended to add to the understanding of the 1964 race.

I agree with Manfred, leave well enough alone.

(I promise to get back on topic in future posts!) :)

Bob Mackenzie

#1588 Catalina Park

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Posted 13 October 2011 - 11:29

I think the 64 Indy was probably the most interesting Indy. The amount of technical change that went on, the new cars, the old cars, the cars that didn't work and the cars that did work. The story of the accident was part of the story of the whole event.
I think that the thread should expand to cover the whole race. I also think that more answers will come from this.

#1589 Michael Ferner

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Posted 13 October 2011 - 14:36

(b) either David or Twinny is prepared to take the time to plough through nearly 1600 posts


Fat chance... :lol:

#1590 HistoricMustang

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Posted 13 October 2011 - 18:32

I didn't intend to create a schism! :drunk:

My post was slightly off topic but intended to add to the understanding of the 1964 race.

I agree with Manfred, leave well enough alone.

(I promise to get back on topic in future posts!) :)

Bob Mackenzie


Hi Bob and certainly was not being critical of the information you provided. In fact, just the opposite as it is most interesting to me and perhaps others.

Since I originated the thread just wanted to suggest that it be expanded using a simple topic modification for those that use the "search" feature. They could find both information on the accident and the entire 1964 event. I also believe that years event is certainly historical and perhaps one of the top two or three Indy 500's.

Certainly would not want the moderators to take on the monumental task of going through all the post.

Henry :wave:

Edited by HistoricMustang, 13 October 2011 - 18:33.


#1591 R.W. Mackenzie

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Posted 14 October 2011 - 17:06

Hi Henry,

No offense taken. Actually it takes a Hell of a lot to offend me!

I've been studying the various films made of the 1964 race and trying to piece the first two laps together to better understand what transpired up to the point of the accident. I don't know if everyone will agree with what I've observed but I will post my interpretation over the course of the coming weekend.

In the meantime, over on another forum, a film clip has been posted that provides a view of the accident not previously seen by me.

Here is the link:

http://www.the-fastl...t...=27&t=12370

You may have to be a registered member of this site, I'm not sure.

This clip is from a DVD titled "Open Wheel Thriller" available here:

http://www.nostalgia.../owthriller.htm

Most of the videos show the accident from further up the track looking back at turn 4. This one shows the accident after MacDonald's initial impact from behind turn 4 looking towards the front straight.

Bob Mackenzie

#1592 Lemnpiper

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Posted 15 October 2011 - 04:45



Hi Folks ,


As someone who has watched for a bit before joining in posting on this thread , this to me has been one of the more interesting threads to read since many of the questions at the beginning of the thread have been resolved.

The downside is that this thread is now 40 pages long(at this point) it may discourage a newbie from reading from the start , but should one choose to do so and have the time you will be rewarded with a discussion that will inform and entertain you as folks with varying viewpoints chime in.

Plus you will see posts from some of the best informed posters here.Including some that havent posted in ages.



So for those reasons i suggest the thread remains as it is , and let it continue to evolve.




Paul

#1593 HistoricMustang

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Posted 15 October 2011 - 18:07

Hi Henry,

No offense taken. Actually it takes a Hell of a lot to offend me!

I've been studying the various films made of the 1964 race and trying to piece the first two laps together to better understand what transpired up to the point of the accident. I don't know if everyone will agree with what I've observed but I will post my interpretation over the course of the coming weekend.

In the meantime, over on another forum, a film clip has been posted that provides a view of the accident not previously seen by me.

Here is the link:

http://www.the-fastl...t...=27&t=12370

You may have to be a registered member of this site, I'm not sure.


Bob Mackenzie


Hi Bob and could you advise under which "topic" the video can be seen. The link provided takes you to the main page (after registration).

Thanks,
Henry

#1594 West3

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Posted 15 October 2011 - 19:24

Hi Bob and could you advise under which "topic" the video can be seen. The link provided takes you to the main page (after registration).

Thanks,
Henry


To view the video, try the following link:

http://www.mediafire...779405kn9qs75qk

You will see a box below the video description which, when clicked, should allow the video to be downloaded or viewed.

Hope this helps.

#1595 R.W. Mackenzie

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Posted 15 October 2011 - 19:53

Or alternatively, click on "Forum", then "Crash Videos" and lastly "1964 MacDonalds/Sachs Indy 500".

#1596 R.W. Mackenzie

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Posted 15 October 2011 - 21:20

For whatever reason this accident has always had a grip on me and from the input of everyone in this forum topic I can see I'm not alone.

It is a passion of mine to try and understand exactly how this catastrophe unfolded from the drop of the flag until the last flames were extinguished. This has led me to read and reread the posts here in an effort to gain an understanding of the facts where they exist and the theories where the facts are lacking.

A number of commercially available videos of the 1964 race have been referenced here and I decided to obtain the ones I didn't already own and, along with the many incredible photographs that have appeared here in this forum, conduct my own thorough analysis to see what conclusions I can come to.

The videos I am referring to are the following:

1. The British Invasion
2. 1964 Race Recap

(Both of these are on the 1960s DVD "Decade of Change" from the IMS box set which I already owned.)

3. Strategy for Speed
4. The 1964 Indianapolis 500 (Dynamic Films)
5. Driver's Decision

(These three are on the Rare Sports Films DVD "1964 at Indy".)

6. The Roadsters Last Triumph (First Turn Productions)

I decided to first focus on events from the drop of the flag until Dave MacDonald begins to spin. This is not as easy to organize in your mind as it may seem. The video segments of the first two laps flash by in such a hurry from so many different vantage points (not always readily identifiable) and sometimes inadvertently in the wrong order. Then they quickly reshow the sequences from entirely different perspectives.

So I went video by video and everywhere a majority of the field passed a specific point on the track I watched in stop motion, advancing frame by frame, and recording the race order at that point. Once I recorded all such instances I created an Excel spreadsheet with these "snapshot" race orders in chronological order from left to right. I left a blank column between each so that I could insert arrows to indicate any changes in position. (I don't know how to attach an Excel file but if anyone wants to see my worksheet you can send me a PM.)

What became clear from the outset was that MacDonald did not, by a considerable margin, make the most aggressive start. In fact he lost two positions at the start and by the point where he lost control in turn four on lap 2 he had only advanced four positions from where he started. That may sound aggressive but that is the same number that Bobby Unser advanced and consider that in the same period Bill Cheesbourg moved up 13 positions and Bob Veith moved up 9 spots.

I've never read any account of the 1964 race that accuses Cheesbourg, Veith or Unser of being overly aggressive at the start of the race. Also, in none of the video clips does MacDonald appear to be driving over his head nor does his car seem on the ragged edge of control. Now for sure I wasn't out there racing wheel to wheel with him so I didn't see what Johnny Rutherford saw that made him think that Dave was going to crash or win.

The following is a summary of MacDonald's progress on the first two laps:

1. Between the drop of the flag and the entrance to Turn 1 Eddie Sachs gets past dropping Dave one spot.

2. Somewhere between the exit of Turn 1 and the South Chute Johnny Rutherford gets past MacDonald (he was trying to stay with Sachs to make a good start.)

3. Between the entry and exit of Turn 2 Dave passes Johnny Boyd.

4. Dave passes Rutherford and then Sachs on the back straight.

5. On the front straight Dave passes Dick Rathmann.

6. Between Turn 1 and Turn 2 Dave passes Len Sutton.

7. Somewhere between the backstraight and Turn 4 Dave passes Don Branson.

Anyway, that is the way I see it. If anyone sees it any differently I'd love to hear it.

Bob Mackenzie

#1597 ZOOOM

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Posted 17 October 2011 - 18:08

The new video is VERY interesting. It shows the very slow pregression of MacDonnalds car accross the track. I always thought the car shot across the track, but the video shows the almost lazy progression. It also appears that Sachs didn't hit Dave when he was on the way to the outside wall, but after he had bounced back off the outside wall back across the track.
I'll have to watch it again and again...
ZOOOM

#1598 R.W. Mackenzie

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Posted 17 October 2011 - 23:40

Hi Zooom,

I don't think the video is shown at full speed. It seems to be slightly slowed down. Another thing that isn't clear from the video is that MacDonald is crossing the track at an angle, not straight across. So he's still moving away from the camera at some speed.

I don't see MacDonald bouncing back off the outer wall before Sachs hits him in this or other clips I've checked. He seems to stop at the outside wall just before impact.

One thing I do wonder from seeing this video is whether anyone else hit Sachs and/or MacDonald after Rutherford, Duman and Unser had cleared the scene. It looks an awful lot like when Boyd, Cheesbourg, White and Ruttman go into the inferno there are additional impacts and flare-ups.

Bob Mackenzie

Edited by R.W. Mackenzie, 17 October 2011 - 23:49.


#1599 R.W. Mackenzie

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Posted 19 October 2011 - 02:13

One of the key topics discussed in this forum is what actually caused Dave MacDonald to lose control in turn 4 at the end of lap 2. The inherent aerodynamic instability of the Thompson cars is suggested as one of the causes and in an earlier post I gave reasons why I thought that might have been the case.

However the more I view the videos, especially those showing the beginning of Dave's spin off turn 4, the more I believe it was something else.

To set the scene, at the drop of the flag Jim Hurtubise gets the jump on Walt Hansgen who had started ahead of him. Whilst throughout the first two laps there are many passes and position changes, Jim and Walt maintain their positions. The gaps changes at different points but it seems to me that Walt is really trying to get his position back.

Behind this Dave MacDonald, having lost two positions at the start is finding enough speed to regain his spot and pick up positions as the first two laps unfold. Down the back straight on the second lap he has passed Sutton and has only Branson between him and Hansgen.

Unfortunately there is no video I have seen that shows what happens from this point until turn 4. There is mention earlier in this topic of aerial views showing the action almost up to the point of the accident but this has not yet surfaced anywhere. However, between the back stretch and the exit of turn 4 MacDonald passes Branson and gets right up on Hansgen's tail. To me this suggests that he had a significant speed advantage over those cars and that he probably came up on Hansgen with a fair bit forward momentum.

Mickey Thompson was quoted as saying that Dave lost it on the straight but I feel this is quite wrong. In the videos showing his spin into the inside wall you can see that this begins somewhere very close to the end of the turn 4 grandstand. In an aerial view of the accident aftermath (I believe it was one of Walter Zoomie's pictures from very early on in this thread and not now accessible) you can see from the racing line that at this point the cars are still in the process of cornering. Stills of Dave first losing control also seem to show the cars immediately behind (Branson and Sutton) are still in cornering mode as they come onto the straight.

The reason I am focusing on these last two points is that if Dave was coming out of turn 4 but still cornering at the limit of adhesion and came up on Hansgen either more suddenly than expected or expecting to take him on the inside and suddenly finding him moved into his path he would have been forced to do one or both of two things. He would have been forced to suddenly turn tighter and/or get out of the gas. Either action performed at or near the limit of adhesion would have likely sent him oversteering into a spin.

You could also suggest that the supposed instability of the Thompson cars would have aggravated the situation but I am not so sure. The basic Thompson car was a fairly conventional space-frame, mid-engined single-seater for the time. It was the unconventional bodywork that seems to have created the stability issues but a number of corrective measures had been taken that probably improved the handling significantly. The venting of the radiator exhaust to the top of the front bodywork in particular seems ahead of its time. And as I mentioned in my earlier post the videos of the first two laps don't show any evidence of instability.

I also do not believe that Walt Hansgen suddenly moved into Dave's path although this is very hard to disprove. The only thing I can say for sure is that Walt had maintained a fairly consistent position relative to Jim Hurtubise through the first two laps. He always seemed to be behind him and slightly inside of him. It is possible however that as they headed onto the front straight he felt he finally had enough steam to make his move.

But in the videos of the beginning of his spin it really seems as though Dave is right up Walt's ass which to me supports the theory that Dave just misjudged how quickly he was catching Walt in turn 4 and his evasive action initiated the spin.

I'm certainly not the first to suggest this and I have no axe to grind or any prejudice as to who or what did or didn't cause the crash. This is just my best take on the what I see from viewing all of the evidence we have seen to date.

I'd love to hear what others think, pro or con, of my analysis.

Bob Mackenzie

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#1600 Manfred Cubenoggin

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Posted 19 October 2011 - 10:54

Very plausible, Bob, but not necessarily the definitive analysis/conclusion. So many variables. The truth is that we shall likely never know.

You are a bonifide engineer...me, just a mere mechancial engineering technician...so I'd like your take on the affect of the upgunning from the 13-inch wheels Mickey designed the car around to the 15-inch rims as stipulated by USAC. Much has been made of this being a huge technical change but was it a crippling element? The ruling concerned the wheel specification. What were the relative dimensions of the actual tires involved? That, to my mind, is the critical factor. If the section heights of the tires were more or less equal, the larger radius wheels would have elevated the car just one inch higher in terms of ride height, not two. Could this not be compensated for in a revised suspension setup with reasonable expectation of retaining performance? Would that extra inch's worth of ground clearance be enough to turn the car from a decent-handling car into a nightmare?