Jump to content


Photo

The Mickey Thompson 'Sears Allstate Special' cars of 1964


  • Please log in to reply
1764 replies to this topic

#351 TrackDog

TrackDog
  • Member

  • 335 posts
  • Joined: August 07

Posted 14 September 2007 - 06:17

Originally posted by Ray Bell
This fuel tank thing also bugs me...

I can't believe there was no tank on the right hand side. I'm prepared to accept that the filler was on the left as the pits and refuelling is on the left, and that the filler neck fuelled both tanks at once.

The first impact damaged the right hand tank, in my estimation, and it erupted in flames. Couldn't it also have been destroyed by that fire? All trace gone?


It would seem that if there was a right-hand tank, there would have to be a rather large crossover pipe, and this would undoubtedly allow the fuel to slosh between tanks during a fuel run...also, wouldn't a crossover play havoc with a pressurized refueling system?

I'm wondering if the rubber bladder wasn't designed so that it would expand somehow; maybe attached to the left side of the car, but capable of occupying a lot of empty space on the right side of the car when full. If so, maybe fuel was indeed present on the right side of the car when the tank was full, and that mght explain why there were 2 explosions.

A balloon, more or less...


Dan

Advertisement

#352 TrackDog

TrackDog
  • Member

  • 335 posts
  • Joined: August 07

Posted 14 September 2007 - 10:11

I also note from the photo that Henry posted that the front wheels of the car are canted to the right and the right rear wheel seems to be pointed straight ahead. The rear-wheel steering must have had just enough travel to offset the loading of the right rear tire in a corner, or some kind of interruptor mechanism that the driver could actuate.

I've also reviewed some youtube films I have of the crash...the second explosion was nearly as violent as the first. I don't see how just a few gallons from Sach's car could cause such a conflagration. I realize camera angles might have something to do with just how huge the explosion was, but both were massive.

Also, the bodywork wasn't ripped away by the initial impact of MacDonald's car and the inside wall...it might have been loosened, but it was intact at least until the moment Sachs hit it. I always figured that the bodywork was consumed in the blaze.

Dan

#353 Tom Glowacki

Tom Glowacki
  • Member

  • 244 posts
  • Joined: December 03

Posted 14 September 2007 - 10:32

Peter Bryant's book, "CanAm Challenger" explains his view, as chief mechanic on the car: A.) he accepts Len Sutton's explanation that McDonald "simply lost it" p.169, B.) "We only had room in our fuel tank for 44 gallons, p. 167, and C.) "The big impact with the wall had broken the right side suspension and pushed it all against the bodywork. The body had been ripped away and had taken a big part of the fuel cell with it. I guess that when that happened, the frame metal hit the wall and caused sparks tht ignited the gasoline." p.170.

Andrew Ferguson's book "Team Lotus" gives the Type 29 and 34 a 42 gallon fuel capacity, with the later Type 38 having 58 gallons, so there is nothing unusual about the 44 gallon capacity in the Thompson car. The really big tanks came along in the next few years.





#354 Henri Greuter

Henri Greuter
  • Member

  • 4,908 posts
  • Joined: June 02

Posted 14 September 2007 - 10:43

Originally posted by TrackDog
I also note from the photo that Henry posted that the front wheels of the car are canted to the right and the right rear wheel seems to be pointed straight ahead. The rear-wheel steering must have had just enough travel to offset the loading of the right rear tire in a corner, or some kind of interruptor mechanism that the driver could actuate.

I've also reviewed some youtube films I have of the crash...the second explosion was nearly as violent as the first. I don't see how just a few gallons from Sach's car could cause such a conflagration. I realize camera angles might have something to do with just how huge the explosion was, but both were massive.

Also, the bodywork wasn't ripped away by the initial impact of MacDonald's car and the inside wall...it might have been loosened, but it was intact at least until the moment Sachs hit it. I always figured that the bodywork was consumed in the blaze.

Dan



Dan,

I think I am one of the many who, based on the size of the fire, always believed that there had been two fuel tanks in The thompson car.
But the evidence I have seen till so far in this thread seems to contradict this generally accepted wisdom.
There's the pic of the car after the accident and nothing like a fuel tank visible on the right.
So it was never there or must have been torn off.

Then, Pete Bryant states within his book that there was only a single tank in the car. There is more written within this book that I have been told about (have yet to see the pages in real) but I believe my informants.
I dare to say that for more than 99% sure, there wasn't a second fuel tank. God forbid what would have happened if there had been a second fuel tank after all.

That the second explosion was so violent, I think there is only one theory for an explanation I can come up with.
According the investigations, the rubber bladder burst open. But I think that it didn't threw out all the fuel in one single moment and that some of the fuel was still within the tank when the car slid back on the track. This explains why the car `drew` that wall of flames within its track.
When Sachs collided with the car, he flattened the blatter and then the fuel that was still left within the tank was released at that moment. And one of his own tanks in the nose of the car also broke. And that may well have caused the second explosion be so big.

That's the best I can come up with right now.


Henri

#355 Henri Greuter

Henri Greuter
  • Member

  • 4,908 posts
  • Joined: June 02

Posted 14 September 2007 - 11:30

Originally posted by Tom Glowacki
Peter Bryant's book, "CanAm Challenger" explains his view, as chief mechanic on the car: A.) he accepts Len Sutton's explanation that McDonald "simply lost it" p.169, B.) "We only had room in our fuel tank for 44 gallons, p. 167, and C.) "The big impact with the wall had broken the right side suspension and pushed it all against the bodywork. The body had been ripped away and had taken a big part of the fuel cell with it. I guess that when that happened, the frame metal hit the wall and caused sparks tht ignited the gasoline." p.170.

Andrew Ferguson's book "Team Lotus" gives the Type 29 and 34 a 42 gallon fuel capacity, with the later Type 38 having 58 gallons, so there is nothing unusual about the 44 gallon capacity in the Thompson car. The really big tanks came along in the next few years.





I think it's fair to say that there were larger fuel tanks in use already. Some of the roadsters did have tanks of larger than 55 gallons. Don't think those long pointed tails were only there because of making the Roadsters look soooooo neat.......
Given the fact that the Offies ran on methanol, they needed bigger tanks. Lotus on the other hand planned to use gasoline from the very beginning which allowed them to built their first cars with such tiny tanks (compared with the roadsters) to begin with.
Buford questioned the reasons of why some of the American built RE cars also had reduced fuel tanks and I think that is indeed a good point. Did all of the builders anticipate that they or their owners would to obtain Ford V8's.

I don't have the literature at hand but somehow I believe I have read somewhere that fuel tank capacity was maxikmised to 75 gaollons as from 1965 on. Then, after the fiery 1974 race the capacity was reduced even further to 40 gallons.

Henri

#356 TrackDog

TrackDog
  • Member

  • 335 posts
  • Joined: August 07

Posted 14 September 2007 - 20:30

Originally posted by Henri Greuter



Dan,

I think I am one of the many who, based on the size of the fire, always believed that there had been two fuel tanks in The thompson car.
But the evidence I have seen till so far in this thread seems to contradict this generally accepted wisdom.
There's the pic of the car after the accident and nothing like a fuel tank visible on the right.
So it was never there or must have been torn off.

Then, Pete Bryant states within his book that there was only a single tank in the car. There is more written within this book that I have been told about (have yet to see the pages in real) but I believe my informants.
I dare to say that for more than 99% sure, there wasn't a second fuel tank. God forbid what would have happened if there had been a second fuel tank after all.

That the second explosion was so violent, I think there is only one theory for an explanation I can come up with.
According the investigations, the rubber bladder burst open. But I think that it didn't threw out all the fuel in one single moment and that some of the fuel was still within the tank when the car slid back on the track. This explains why the car `drew` that wall of flames within its track.
When Sachs collided with the car, he flattened the blatter and then the fuel that was still left within the tank was released at that moment. And one of his own tanks in the nose of the car also broke. And that may well have caused the second explosion be so big.

That's the best I can come up with right now.


Henri


I guess that makes sense.

Dan

#357 TrackDog

TrackDog
  • Member

  • 335 posts
  • Joined: August 07

Posted 14 September 2007 - 20:44

Originally posted by Henri Greuter



I think it's fair to say that there were larger fuel tanks in use already. Some of the roadsters did have tanks of larger than 55 gallons. Don't think those long pointed tails were only there because of making the Roadsters look soooooo neat.......
Given the fact that the Offies ran on methanol, they needed bigger tanks. Lotus on the other hand planned to use gasoline from the very beginning which allowed them to built their first cars with such tiny tanks (compared with the roadsters) to begin with.
Buford questioned the reasons of why some of the American built RE cars also had reduced fuel tanks and I think that is indeed a good point. Did all of the builders anticipate that they or their owners would to obtain Ford V8's.

I don't have the literature at hand but somehow I believe I have read somewhere that fuel tank capacity was maxikmised to 75 gaollons as from 1965 on. Then, after the fiery 1974 race the capacity was reduced even further to 40 gallons.

Henri


I remember reading in Parnelli: A Story Of Auto Racing, that Jones was running a strategy of a half tank load per stop, believing that the car would be lighter that way, and easier on tires. Also, nobody in the Offy camp thought that the Fords would be as fast as they were on gasoline. I think that Jones said he started on 55 gallons of methanol, about half a tank, and when he stopped, he got another 55 gallons...the buildup of fumes from the volume of fuel and air created an ideal environment for the static electricity that sparked when the fuel hose nozzle was disconnected, and the tank blew. Jones said they would have fun on gasoline if the team had known that the Fords would have been so fast on it. If his car would have exploded in the pits on gasoline, THAT would have been a disaster that would have dwarfed the 2nd lap crash.


Dan

#358 McGuire

McGuire
  • Member

  • 9,218 posts
  • Joined: October 03

Posted 15 September 2007 - 10:53

Originally posted by Henri Greuter


Then, Pete Bryant states within his book that there was only a single tank in the car. There is more written within this book that I have been told about (have yet to see the pages in real) but I believe my informants.
I dare to say that for more than 99% sure, there wasn't a second fuel tank. God forbid what would have happened if there had been a second fuel tank after all.

That the second explosion was so violent, I think there is only one theory for an explanation I can come up with.
According the investigations, the rubber bladder burst open. But I think that it didn't threw out all the fuel in one single moment and that some of the fuel was still within the tank when the car slid back on the track. This explains why the car `drew` that wall of flames within its track.


That is by far the most plausible explanation. There is no particular reason to assume that the initial fire against the inside wall consumed all the fuel aboard MacDonald's car. Meanwhile, it is entirely reasonable that the impact from Sachs' car would splash and redistribute the remaining fuel in the MacDonald car, causing the flames to flare up a second time.

#359 Henri Greuter

Henri Greuter
  • Member

  • 4,908 posts
  • Joined: June 02

Posted 17 September 2007 - 10:40

Originally posted by TrackDog


I remember reading in Parnelli: A Story Of Auto Racing, that Jones was running a strategy of a half tank load per stop, believing that the car would be lighter that way, and easier on tires. Also, nobody in the Offy camp thought that the Fords would be as fast as they were on gasoline. I think that Jones said he started on 55 gallons of methanol, about half a tank, and when he stopped, he got another 55 gallons...the buildup of fumes from the volume of fuel and air created an ideal environment for the static electricity that sparked when the fuel hose nozzle was disconnected, and the tank blew. Jones said they would have fun on gasoline if the team had known that the Fords would have been so fast on it. If his car would have exploded in the pits on gasoline, THAT would have been a disaster that would have dwarfed the 2nd lap crash.


Dan


One of the things that has always annoyed me was how everyone seemed to blame the use of gasoline for the disaster while in fact Parnelli Jones had a fire himself as well, despite running on methanol. And that this accident took some time before everyone realized that Jones was on fire.
Or have a look on what happened with Ronnie Duman's carafter he vacated the car. It looks pretty well once he got out but in pix taken later on the damage is quite severe. And all of that thanks to the much more innocent methanol....

But that was before I found out thanks to this thread that McDonald's car contained only 44 gallons of fuel and that the scen from hell we saw in Turn 2 was caused by some 55 gallons of gasoline at the very maximum.
I really don't want to think about what would have happened had it been indeed twice as much fuel that had been involved, let olen when it would have been three times as much if all of the tanks in Sachs' car had burst as well.
I do understand and respect the outcries because of the gasoline a lot better by now and must say that it does make more sense.
Nevertheless, things could have been so different if McDonald had driven in a car with a more secure fuel tank installation. If the Thompson had a monocoque construction like the Lotus and/or the Shrike...

But that's one of the many `If only` thoughts yet again.


By the way. I must correct myself too:
I wrote:

[B]Then, after the fiery 1974 race the capacity was reduced even further to 40 gallons.[B]

that must be:
Then, after the fiery 1973 race the capacity was reduced even further to 40 gallons.

The starting incident with Salt Walther spraying some 70 gallons of methanol on the front stretch, including within the crowd was likely the main reason.
Imagine that because of the collisions the burning MacDonald wreck had become airbone and gyrating like a gyroscope like happened with Walther 9 years later....

As horrible as it was, IMS was still very, very lucky in 1964.


Henri

Advertisement

#360 TrackDog

TrackDog
  • Member

  • 335 posts
  • Joined: August 07

Posted 17 September 2007 - 11:40

I remember reading somewhere that by 1973, the sponges that had been used in the fuel tanks just after the 1964 crash were no longer being used because those 1000hp+ engines were sucking so much methanol that every bit of tankspace had to be utilized to carry fuel. Things weren't quite as bad as they were in '64, but they were alarmingly close. The tanks had bladders and they would self-seal, but they would obviously split open in severe crash conditions, as the Walther and Savage crashes would prove.

I believe it was Mario Andretti that was quoted regarding this, and he added that with over 1000hp, it was easy to get wheelspin in the turns. I always wondered if something like that might have happenned to Swede.


Dan

#361 Gerr

Gerr
  • Member

  • 687 posts
  • Joined: April 00

Posted 17 September 2007 - 13:08

Originally posted by Henri Greuter



One of the things that has always annoyed me was how everyone seemed to blame the use of gasoline for the disaster while in fact Parnelli Jones had a fire himself as well, despite running on methanol. And that this accident took some time before everyone realized that Jones was on fire.
Or have a look on what happened with Ronnie Duman's carafter he vacated the car. It looks pretty well once he got out but in pix taken later on the damage is quite severe. And all of that thanks to the much more innocent methanol....

But that was before I found out thanks to this thread that McDonald's car contained only 44 gallons of fuel and that the scen from hell we saw in Turn 2 was caused by some 55 gallons of gasoline at the very maximum.
I really don't want to think about what would have happened had it been indeed twice as much fuel that had been involved, let olen when it would have been three times as much if all of the tanks in Sachs' car had burst as well.
I do understand and respect the outcries because of the gasoline a lot better by now and must say that it does make more sense.
Nevertheless, things could have been so different if McDonald had driven in a car with a more secure fuel tank installation. If the Thompson had a monocoque construction like the Lotus and/or the Shrike...


Henri


I don't think the quantity of gasoline had much to do with the explosion of MacDonald's car. The car hit the wall on the right rear corner. The wheel and axle appear to have smashed into the fuel injection on the RH side of the engine, possibly jamming the throttle and probably severing a high pressure hose. Have a look at the photo of the wreck in post 142 and you can see some of the damage to the FI.
I don't know the capacity of the pump used on the Ford 255, but some Hilborn pumps of the era are rated as high as... 13.72 gpm @ 1800 rpm with 50 lbs. pressure. The high pressure and high volume spray with ignition would result in a very large explosion and a massive fire. The amount of fuel would only dictate the length of time the fire would last.

Gregory's accident and the resulting (far less severe) fire in practice seems to be almost the same thing. The right hand side of car was whacked with the rear wheel smashing the FI. There is a good pic on page 111 of the yearbook of the damage.

#362 HistoricMustang

HistoricMustang
  • Member

  • 4,076 posts
  • Joined: November 03

Posted 17 September 2007 - 21:41

Originally posted by Gerr


I don't think the quantity of gasoline had much to do with the explosion of MacDonald's car. The car hit the wall on the right rear corner. The wheel and axle appear to have smashed into the fuel injection on the RH side of the engine, possibly jamming the throttle and probably severing a high pressure hose. Have a look at the photo of the wreck in post 142 and you can see some of the damage to the FI.
I don't know the capacity of the pump used on the Ford 255, but some Hilborn pumps of the era are rated as high as... 13.72 gpm @ 1800 rpm with 50 lbs. pressure. The high pressure and high volume spray with ignition would result in a very large explosion and a massive fire. The amount of fuel would only dictate the length of time the fire would last.

Gregory's accident and the resulting (far less severe) fire in practice seems to be almost the same thing. The right hand side of car was whacked with the rear wheel smashing the FI. There is a good pic on page 111 of the yearbook of the damage.


Very good observation. Thanks!

During the mid-sixties, at Indy, did the fuel pump continue to energize as long as there was electrical power or was there a "fail safe"?

Henry

#363 TrackDog

TrackDog
  • Member

  • 335 posts
  • Joined: August 07

Posted 17 September 2007 - 22:11

Originally posted by Gerr


I don't think the quantity of gasoline had much to do with the explosion of MacDonald's car. The car hit the wall on the right rear corner. The wheel and axle appear to have smashed into the fuel injection on the RH side of the engine, possibly jamming the throttle and probably severing a high pressure hose. Have a look at the photo of the wreck in post 142 and you can see some of the damage to the FI.
I don't know the capacity of the pump used on the Ford 255, but some Hilborn pumps of the era are rated as high as... 13.72 gpm @ 1800 rpm with 50 lbs. pressure. The high pressure and high volume spray with ignition would result in a very large explosion and a massive fire. The amount of fuel would only dictate the length of time the fire would last.

Gregory's accident and the resulting (far less severe) fire in practice seems to be almost the same thing. The right hand side of car was whacked with the rear wheel smashing the FI. There is a good pic on page 111 of the yearbook of the damage.


A very astute and plausible explanation for the first explosion...but, it should be remembered that Johnny Rutherford's car ran over the back of MacDonald's, and several injector horns were imbedded in the rear of his roadster. That might be a possible cause of damage to the FI, or maybe the damage done by Rutherford's car was on the left side of MacDonald's engine. I was surprised to see that the exhaust system of Dave's car was intact, even with damage to the injectors...the more I think about it, the more sense Gerr's explanation makes.

Is there any mention of this in CAN AM CHALLENGER?


Dan

#364 HistoricMustang

HistoricMustang
  • Member

  • 4,076 posts
  • Joined: November 03

Posted 17 September 2007 - 23:03

Originally posted by Lotus23
A fascinating thread. I really enjoy reading the input, even if I don't concur with it all.

Like Buford, I was there that terrible day. My first Indy -- I was sitting directly across from the pit entrance, close enough to have the whole scene seared into my memory. In the past 61 years, I've seen more on-track fatalities than I care to recount, but the horror of that scene was in a league of its own.

I took a bunch of 35mm snapshots, but they mostly just showed huge columns of smoke. I do recall the great difficulty the firemen had in putting out many of the flames: they'd die down to nothing, apparently extinguished, then 10-15 seconds later they'd flare back up again. And again.


Could the issues with putting out the flame be associated with the MacDonald fuel pump simply adding more and more fuel to the fire?

Henry

#365 Gerr

Gerr
  • Member

  • 687 posts
  • Joined: April 00

Posted 17 September 2007 - 23:39

Originally posted by HistoricMustang




During the mid-sixties, at Indy, did the fuel pump continue to energize as long as there was electrical power or was there a "fail safe"?

Henry


The fuel pump was always mechanical at Indy. On the Ford it was driven by RH exhaust cam.

#366 Gerr

Gerr
  • Member

  • 687 posts
  • Joined: April 00

Posted 17 September 2007 - 23:55

Originally posted by TrackDog


A very astute and plausible explanation for the first explosion...but, it should be remembered that Johnny Rutherford's car ran over the back of MacDonald's, and several injector horns were imbedded in the rear of his roadster. That might be a possible cause of damage to the FI, or maybe the damage done by Rutherford's car was on the left side of MacDonald's engine. I was surprised to see that the exhaust system of Dave's car was intact, even with damage to the injectors...the more I think about it, the more sense Gerr's explanation makes.


Dan


I think Rutherford drove over Sachs' car. There is an IMS pic on page 206 of the 1983 Hungness yearbook showing JR just clearing the fire with Sachs just behind (only a few feet) and at 90 degrees to his roadster.

The same photo is used here

http://www2.indystar...g/1964_page.gif

but it is very hard to see any detail.

#367 Tom Glowacki

Tom Glowacki
  • Member

  • 244 posts
  • Joined: December 03

Posted 18 September 2007 - 00:56

Assuming the fuel pump was still running, wasn't it pulling fuel OUT of the fuel tank and into the engine? If the pump was running and either the fuel line was ruptured, or maybe the return line was pumping fuel into the tank, I don't see your scenario as realistic, given that the fuel tank had return been hit quite hard twice, ruptured, and had sprayed fuel all over the place. Certainly most of the fuel must have exploded out of the tank and caught fire before McDonald's car came to rest.

#368 Ray Bell

Ray Bell
  • Member

  • 54,278 posts
  • Joined: December 99

Posted 18 September 2007 - 01:31

You'd be right there, Tom...

And an explosive fire like that couldn't possibly come from the flow from any fuel pump.

#369 Gerr

Gerr
  • Member

  • 687 posts
  • Joined: April 00

Posted 18 September 2007 - 04:17

Originally posted by Tom Glowacki
Assuming the fuel pump was still running, wasn't it pulling fuel OUT of the fuel tank and into the engine? If the pump was running and either the fuel line was ruptured, or maybe the return line was pumping fuel into the tank, I don't see your scenario as realistic, given that the fuel tank had return been hit quite hard twice, ruptured, and had sprayed fuel all over the place. Certainly most of the fuel must have exploded out of the tank and caught fire before McDonald's car came to rest.


It is an assumption, but the RR wheel had smashed the fuel injection rack likely jamming the throttle open. The high-pressure lines to the injector nozzle were just under the rack above the intake cam housing, exposed to the same type of damage. If one or more of these lines were torn and the engine was still running, fuel would spray out at an unrestricted rate and would atomize and would be hugely more explosive than liquid gasoline.

MacDonald's car had it's only fuel tank on the LH side. The car hit the wall with the RR corner, crossed the track and was hit by Sachs in the right side. The LH side, the fuel tank side was much, much less fire damaged than the right as shown in a photo on page 135 of the 1964 yearbook.

In the same accident a few yards away, Norm Hall hit the wall tail first in his roadster. The fuel tank split and dumped out 54 gallons of fuel. It just gushed out, but no atomization and no fire. Just a big puddle.

#370 TrackDog

TrackDog
  • Member

  • 335 posts
  • Joined: August 07

Posted 18 September 2007 - 07:10

I've been reviewing my youtube clips of the accident yet again, and I can certainly see that the initial fire from MacDonald's crash into the inside wall is initially a flash-type explosion, and quickly dies down quite a bit...then there's a steady stream of fire following the car back up the track. The body is still attached to the chassis, and the car is travelling backwards as it slides across the track. Sachs hits it almost broadside, and there's a second, much larger explosion of longer duration. Atomized fuel would indeed be more likely to burn rapidly, as in the first explosion.

As for Sachs hitting MacDonald on the right side, well...Dave's car is travelling backwards up the track, so Sachs wouldn't be able to hit the right side of his car. It has to be a left side impact. This could indeed burst the fuel bladder and with the additional explosion of Sachs' front tank, this could explain the huge fireball...it would be almost equivalent to a 55 gallon drum exploding in terms of volume. And, if MacDonald's throttle was jammed open, the fuel pump would be spreading fuel all over the area, especially if MacDonald was hit by several cars, as it has been pretty well established that it was.

Rutherford, by all accounts that I've read, either drove between Sachs and over MacDonald, or under the rear of Sachs and over the top of MacDonald. Fuel injector horns from MacDonald's car were found imbedded in the rear of Rutherford's roadster. Chuck Stevenson apparently clipped the front of Sachs's car.

The chassis of MacDonald's car was severely bent, almost "L" shaped; I always assumed it was from the impact of Sachs' car, but it would also be consistent with a hard right rear impact with the wall. If it hit the wall hard enough to bend the frame, then it's also probable that it did the damage to the engine that Gerr is postulating. Also, both rear tires were torn off Dave's car...possibly from Sachs hitting the left, and maybe Rutherford coming back down on the track, post impact. Or, if a tire were knocked loose from hitting the wall, maybe the impact of Sachs' car was enough to knock them both off.


It would seem that we've found the cause of the first explosion...



Dan

#371 Henri Greuter

Henri Greuter
  • Member

  • 4,908 posts
  • Joined: June 02

Posted 18 September 2007 - 07:34

Rutherford must have had a wild ride, bouncing over McDonalds's car.
But he also must hve been rather close to Eddie too.
Remember that apart for the injection horns (were they really MacDonalds? couldn't they have been from Eddie's car?), they also found the lemon that Eddie carried around his neck.
Now, how long was that string? Probably not that long to make sure it was close to his mouth.
Or had the string broke alread and was the lemon already flying off from Sachs and picked up by Rutherford when he went through the carnage?


Other than that, quite an interesting story on the fuel pump and its share in the disaster.
The question that comes to my mind however is, if the fuel pump was mechanical and on the right side of the engine, wasn''t it damaged instantly by the impact with the wall?. The car hit the wall with the right side.
And how sure can we be that the engine was still running after that smash against the wall?
If it had stopped revving, then the fuel pump was switched off too.

This is not that I don't accept the theory by the way.



Henri

#372 TrackDog

TrackDog
  • Member

  • 335 posts
  • Joined: August 07

Posted 18 September 2007 - 09:04

Originally posted by Henri Greuter
Rutherford must have had a wild ride, bouncing over McDonalds's car.
But he also must hve been rather close to Eddie too.
Remember that apart for the injection horns (were they really MacDonalds? couldn't they have been from Eddie's car?), they also found the lemon that Eddie carried around his neck.
Now, how long was that string? Probably not that long to make sure it was close to his mouth.
Or had the string broke alread and was the lemon already flying off from Sachs and picked up by Rutherford when he went through the carnage?


Other than that, quite an interesting story on the fuel pump and its share in the disaster.
The question that comes to my mind however is, if the fuel pump was mechanical and on the right side of the engine, wasn''t it damaged instantly by the impact with the wall?. The car hit the wall with the right side.
And how sure can we be that the engine was still running after that smash against the wall?
If it had stopped revving, then the fuel pump was switched off too.

This is not that I don't accept the theory by the way.



Henri


Rutherford was right behind Eddie, and slammed on his brakes. The rear end of Sachs' car lifted as he hit MacDonald. Rutherford probably went under Sachs and over MacDonald. Every account I've read that mentions the injector horns stuck in Rutherford's car has attributed them to MacDonald's car.


Dan

#373 HistoricMustang

HistoricMustang
  • Member

  • 4,076 posts
  • Joined: November 03

Posted 18 September 2007 - 21:30

For any of the members that may have a copy of "The British Invasion - Indianapolis 500" I would be interested in your observations at 9:56 into the video.

I personally do not have a copy but am being told:

"This film shows a number of important things. At 9:56 into the tape, it shows the right wheel fold in against the inner bodywork hard enough to break a large piece of bodywork off (Dave MacDonald car)."

Also being told:

"Also, it shows Dave repassing both Sachs and Rutherford on the backstraight.(they both passed Dave on the start). This happens on the first lap, and clearly shows Dave was not even close to the infield grass as was stated by JR."

Can anyone verify this?

As usual, thanks for the help.

Henry

#374 Tom Glowacki

Tom Glowacki
  • Member

  • 244 posts
  • Joined: December 03

Posted 19 September 2007 - 01:16

Originally posted by TrackDog
I've been reviewing my youtube clips of the accident yet again, and I can certainly see that the initial fire
The chassis of MacDonald's car was severely bent, almost "L" shaped; I always assumed it was from the impact of Sachs' car, but it would also be consistent with a hard right rear impact with the wall. If it hit the wall hard enough to bend the frame, then it's also probable that it did the damage to the engine that Gerr is postulating. Also, both rear tires were torn off Dave's car...possibly from Sachs hitting the left, and maybe Rutherford coming back down on the track, post impact. Or, if a tire were knocked loose from hitting the wall, maybe the impact of Sachs' car was enough to knock them both off.
Dan



That is definitely not what the photo on page 171 of Peter Bryant's book shows. The picture is taken from directly behind the left rear wheel. The chassis is very straight, and the left rear wheel and tire are still firmly attached to the chassis, and look to be virtually undamaged. The left side fuel injectors are still on the engine, and while you cannot see the right side injectors as they would be off of the photo, the roll bar brace on the right and the right side exhaust manifold appear to be undamaged. The right front wheel and tire may, or may not be still barely attached to the chassis, as you don't get a clear view of the suspension and the tire is in about the right spot but clearly the upper suspension, at least, is gone.

#375 TrackDog

TrackDog
  • Member

  • 335 posts
  • Joined: August 07

Posted 19 September 2007 - 02:50

Originally posted by Tom Glowacki



That is definitely not what the photo on page 171 of Peter Bryant's book shows. The picture is taken from directly behind the left rear wheel. The chassis is very straight, and the left rear wheel and tire are still firmly attached to the chassis, and look to be virtually undamaged. The left side fuel injectors are still on the engine, and while you cannot see the right side injectors as they would be off of the photo, the roll bar brace on the right and the right side exhaust manifold appear to be undamaged. The right front wheel and tire may, or may not be still barely attached to the chassis, as you don't get a clear view of the suspension and the tire is in about the right spot but clearly the upper suspension, at least, is gone.


Tom,

I haven't been able to see Bryant's book, but I'm wondering if there isn't a misprint...if you check out post #142, you'll see in the overhead shot that the car with the rear wheels still attached and the straight chassis is Sachs' car, the one on the left. MacDonald's car is clearly bent into an "L" shape, with both rear wheels missing, and significant damage to the right side of the engine, as shown in the second photo. It's clear from these photos that MacDonald's car was much more badly damaged in the crash than Sachs' was...and it really isn't surprising, since it impacted the wall; Sachs' car; and at least one more impact, from Rutherford.

Like I said, I haven't read the book, but you seem to be describing Sachs' car after the crash.



Dan

#376 Tom Glowacki

Tom Glowacki
  • Member

  • 244 posts
  • Joined: December 03

Posted 19 September 2007 - 04:17

Dan,

I'll agree that the right side of the McDonald car is stove in. But the Bryant book photo on P. 170 is clearly the McDonald car, and is captioned as such, no mistake. Now that I look at that picture again, the car has a "list to starboard", which would be consistent with the photo at Post 142, and both right side wheels being off. That chassis damage seems to be more in the vertical plane than in the horizontal, and is pretty localized. The right side of the chassis is still remarkably straight in the Bryant picture.

#377 Henri Greuter

Henri Greuter
  • Member

  • 4,908 posts
  • Joined: June 02

Posted 19 September 2007 - 06:37

Originally posted by HistoricMustang
For any of the members that may have a copy of "The British Invasion - Indianapolis 500" I would be interested in your observations at 9:56 into the video.

I personally do not have a copy but am being told:

"This film shows a number of important things. At 9:56 into the tape, it shows the right wheel fold in against the inner bodywork hard enough to break a large piece of bodywork off (Dave MacDonald car)."

Also being told:

"Also, it shows Dave repassing both Sachs and Rutherford on the backstraight.(they both passed Dave on the start). This happens on the first lap, and clearly shows Dave was not even close to the infield grass as was stated by JR."

Can anyone verify this?

As usual, thanks for the help.

Henry




I have that video somewhere in my collection.
Will have a look and let you know ASAP.
First have to dig through some boxes in order to find it.


Henri

#378 HistoricMustang

HistoricMustang
  • Member

  • 4,076 posts
  • Joined: November 03

Posted 19 September 2007 - 10:35

Originally posted by Henri Greuter




I have that video somewhere in my collection.
Will have a look and let you know ASAP.
First have to dig through some boxes in order to find it.


Henri


Henri, my apology, but interest should be at the 9:36 point, not the 9:56 point in the video.

A simple typing mistake on my part.

Henry

#379 Henri Greuter

Henri Greuter
  • Member

  • 4,908 posts
  • Joined: June 02

Posted 19 September 2007 - 10:43

Originally posted by HistoricMustang


Henri, my apology, but interest should be at the 9:36 point, not the 9:56 point in the video.

A simple typing mistake on my part.

Henry


OK, no problem.
Was going to look to the entire part from start to restart to begin with in case I do spot something else as well.


Henri

Advertisement

#380 HistoricMustang

HistoricMustang
  • Member

  • 4,076 posts
  • Joined: November 03

Posted 19 September 2007 - 21:20

Originally posted by Henri Greuter


OK, no problem.
Was going to look to the entire part from start to restart to begin with in case I do spot something else as well.


Henri


Henri, please check your PM's! :wave:

#381 HistoricMustang

HistoricMustang
  • Member

  • 4,076 posts
  • Joined: November 03

Posted 19 September 2007 - 22:34

Additional information from TNF.

Henry

http://forums.autosp...y=&pagenumber=1

#382 Henri Greuter

Henri Greuter
  • Member

  • 4,908 posts
  • Joined: June 02

Posted 20 September 2007 - 07:22

Originally posted by HistoricMustang


Henri, please check your PM's! :wave:



Henry,

thanks for the PM, keep an eye open on your box for reply that will follow.
Now: the film: I've seen it.


First: I am aware of the existance of VCR films released by the Speedway about each year, these are tapes of about half an hour or so. I've seen lots of them in '88 and '89 during my first two years when I attended the Month of May.
I don't have access to these films because of the differences in VCR systems in USA and Europe.
But from my memory, lots of the footage of these films are also used in the "Decade of..." DVD series released by the Speedway.

British Invasion:, I got the feeling that the same footage as used on this tape as well as on the 1964 Speedway tape. I didn't look at the 1964 report on the decade DVD yet.

I have watched the film. By the way, In an edited version it is also a bonus track on the 60’s DVD of the IMS Decade series. When I found out that the part between start and restart were the same on the "British Invasion" video and the bonus track on "60 Decade" I watched on the DVD because of better still's and slow motion capabilities of the DVD.

The only thing that I can find on this particular version of the film is the first passage through Turn 1. You can see that Eddie Sachs is ahead of Dave at that time. On the inside of the turn is Johnny Boyd who has the entire car below the white line, then Dave and Rutherford on the right.
Boyd is faster so he edges ahead of Dave and then Dave dives down and his left wheels do drop below the white line, he is cutting off Ronnie Duman by then. About 1/4th of the car is on the left of the white line, he is not close to the grass in that turn. It appears as if Johnny Boyd is drifting back to the right, back onto the track again with Dave diving into his slipstream.
The sequence starts too late to make up if Johnny went under the white line while he felt forced to do so because of Dave next to him.
Also Bobby Unser in the 4WD Novi is below the white line with the entire car. Dave isn’t, but it is clear to see that he dives rather deep in the turn. But Johnny Boyd directly ahead, and Ronnie Duman directly behind Dave were much deeper below the white line than Dave was.

You also see the cars pass through the short chute for the first time. Rutherford is ahead of Dave at that moment again, an entire car length, he is near the wall, Dave appears to be low but not ridiculously low.

You mentioned a seche on the backstraight. I couldn't find that on VCR or DVD. I got the feeling that what you described as being the back straight was in fact the short shute scene I describe.

If this is indeed the case: Rutherford was ahead of Dave at that poin so his claims that Dave was almost in the grass doen't hold up for the part between the actual start and the first short chute. But that doesn't mean that he was mistaken. It could have been that after passing through Turn 2 and thereafter Dave was close to the grass. But I haven't found evidence for that since i haven't seen film footage of that. On my verions of "British Invasion" there is no Backstraight sceneriy recognizable before the accident.


When watching the accident itself at the slowest speed possible at my player, Dave had already lost control when he came in sight of the camera.
When he hit the wall there is a white puff visible at the very right edge of the screen, I think that it is at about cockpit level. But the car is hidden behind the wall thus where it comes from? The next frame sees the white cloud increased an moved a bit to the left compared with the previous frame. I assume this is because of the car having moved along the wall to the left as well. Then the next frame sees a second white cloud appear, more to the left, in the center of the frame. I can’t make up if this is a new cloud or still a follow-up of the first cloud but having moved to the left, along with the car. Because at the left edge of the screen you can still see some leftovers of the cloud as it appeared first .
The next frame is the first with fire. And given the fact that the car must have moved along the wall a bit already, I get the feeling that the center of ignition was just a little behind the front wheels, at the level of the steering wheel. It wasn't at engine level.

The fire didn’t start instantly when the car hit the wall, there was a split second delay between the collision with the wall and the moment that the fire broke out. I've read (als posted) theories that the fire started once the fuel bladder was ruptured and this did not happen at the moment of impact but a tiny amount of time later.

Will take a bit more time but I will check the firt two laps footage on the FirstTurnProduction film of 1964 another time. I do recall there is some footage of turn Three in this. By then McDonald was ahead of Sachs again in this piece but I didn't pay attention about how low he was on the track.
Don't know if I'm able to report about that tomorrow but otherwise, after the weekend.

Hope that for the time being this is of some help.
If there are other people out her who have that 60's decade DVD by the Speedway, is anyone willing to have a look to the footage from start to accident as well and let us know what he/she thinks about it? I don't beg for support but I hope to hear what other think of it and do agree with what I saw and think about it. And if people feel different about it, please let it know.

thanks,

Regards,

Henri

#383 TrackDog

TrackDog
  • Member

  • 335 posts
  • Joined: August 07

Posted 20 September 2007 - 20:45

I'm wondering if the cloud Henri saw might have been concrete dust ftrom the initial impact against the wall...just a thought...


Dan

#384 Henri Greuter

Henri Greuter
  • Member

  • 4,908 posts
  • Joined: June 02

Posted 21 September 2007 - 08:46

Originally posted by TrackDog
I'm wondering if the cloud Henri saw might have been concrete dust ftrom the initial impact against the wall...just a thought...


Dan



A good thought. Given the fact that in one frame you see two plums of white at two different locations, why not?

Henri

#385 Henri Greuter

Henri Greuter
  • Member

  • 4,908 posts
  • Joined: June 02

Posted 21 September 2007 - 08:59

Originally posted by Henri Greuter



Will take a bit more time but I will check the firt two laps footage on the FirstTurnProduction film of 1964 another time.
Henri



STOP READING THIS MESSAGE IF YOU DON'T WANT TO BE CONFRONTED WITH GRUESOME DETAILS ABOUT THE ACTUAL ACCIDENT OF DAVE MACDONALD




I have done this by now.

In advance my apologies for the gruesome details I tell in this writing.

I have verified the 60’s Decade chapter 1964, the footage of the start and accident is identical to what is used in the bonus version of “British Invasion” as used on the same DVD.
The first passage through the short chute as I described, when I counted, Rutherford was 15th, Dave was 16th.

Also had a look again at the DVD “The Roadster’s last triumph” by First Turn Productions. The quality of the film used is not that perfect but it has footage of the first time that the field goes through Turn 2. The cars are difficult to identify and I was unable to make a positive identification of Dave. But I think I did spot him and assuming I’m correct, within that scene he wasn’t way off line and in 15th spot.

The first passage through Turn 3: I think I spotted Dave but it is impossible for me to pinpoint exactly in which position he is. No cars doing strange.

The first passage through Turn Four, I recognized Dave, he is 12th at the moment. You see the cars heading into 4, seen from the chute, looking into their tailpipes. Now here it appears a bit as if Dave closes in rapidly on the car in front of him and the rear of the car stepping out sideways but caught up in time to continue. (6:44 to 6:46 in the film)

7:15 in the film.
Out of turn 2 for the second time. I recognized Hurtubise in 8th, Hansgen in 9th and an unidentified driver in 10th, maybe Sutton? Dave is 11th. He is rather low in the turn but so is Hansgen as well as the car right behind Dave. Behind Dave two cars, then a gap and then close behind another Sachs, Rutherford, Duman, a gap of about two cars
and a 4th car: Veith.

The film then shows Turn 4 as seen from the front straight but way too many cars pass without an accident and I suspect this footage being from a later moment in the race.





STOP READING THIS MESSAGE IF YOU DON'T WANT TO BE CONFRONTED WITH GRUESOME DETAILS ABOUT THE ACTUAL ACCIDENT OF DAVE MACDONALD





The accident.
The DVD has footage taken from further away, you can see the people, among them the man who shot the well known footage of the car hitting the wall.
In this footage the car is further away ad less sharp but the impact is kind of similar to see: a white spray and then: Boom. Remarkable: initially the explosion is white on the left side, the flames are initially on the right side of the screen but eventually the flames expand and engulf the entire car.
Then you can see that the car comes back from the wall and is thrown on the track but with the nose in forward direction: it has done a full 360 by now. You can still see the outlines of the left sidepod on the car even the letters on the side can still be seen, the tip of the nose however is bend more upward.
Now, when did this happen? another result of the inpacht on the wall? In the moments before hitting the wall the nose tip appears to be still in the correct position.
The car spun anticlockwise to the wall but I can't verify if the car made a ful twist anticlockwise or of the car rotated clockwise back into the right direction because of being bounced back onto the track again.
Then the car turns around again, rotating clockward. During this twist I think that I can see fuel being thrown out of the car, la little ahead of the left front wheel. This fuel also ignites and then the front of the fireball is in front of the car for a meter or thereabout. Two heads block the view for a while but when the car comes in sight again the right side of the car is exposed but the sidepod structure is missing. Flames only at engine level and ahead of the front wheels but the upper surface of the car is ablaze. The right rear suspension has collapsed and the wheel hanging onto the wreck. The top of Dave’s helmet visible briefly before the car becomes engulfed in flames again. The car appears to be close to the outside wall by now. I think I can see some of the tubframe but I can’t identify anything that suggests me that there is a fuel tank on that side of the car. While, at least for a brief moment, there are no flames on that side of the car between the wheels, I think that here we have the definitive approval that there was no right side fuel tank in the car. I can’t imagine that if there was a tank on that side that it didn’t burn or contributed to the fire in this phase of the crash.
Then an explosion, Dave’s car disappears in a big cloud of fire. It looks as if the car hits the wall but likely this was the impact of Rutherford and/or Sachs. A few frames later Duman and Bobby Unser appear out of the flames. A scene much like the famous Life (or was it Time?) pictures. A few frames later the tail of Rutherford’s car is visible, a little flame at cockpit level in front of the left rear tire, close to the ground. Four frames later the entire Rutherford car visible and the fire is right behind his left front up till windscreen level.
From here nothing on Dave for a while but we see the first impact of Duman against the wall. He also created a white cloud when hitting the wall.
This does confirm that Eddie hit Dave on the left side of the car, the side on which the fuel tank was. But it also appears to me as if Johnny Rutherfords collision somehow contributed to the explosion. But if that is true?
But though the camera is directed on the scene during the impacts, you can’t recognize either Sachs or Rutherford running into or over Dave’s car. Duman, Unser and Rutherford all of a sudden appear out of the flames.

I want to leave it till here.

There is some more footage of how Rutherford, Unser and Duman got through the carnage but then seen from a larger distance, but more than telling enough. How Rutherford got out of the carnage on fire but the wind blowing the flames off for example.
But as for a description of what happened this is enough I think.
If you want to see it with your own eyes, get the DVD. It''s quite an interesting DVD anyway about a interesting year within speedway history, tragically tainted by this accident.
But be warned, this is frightening to watch.
Here's the link to their website.

http://www.firstturn.net/index.html


Regards,


Henri.

#386 HistoricMustang

HistoricMustang
  • Member

  • 4,076 posts
  • Joined: November 03

Posted 21 September 2007 - 22:44

Do any of the members have information on how "Flagging and Scoring" rules were applied during the 1964 event.

Was it simply at the Start/Finish flag stand or did the speedway have a "light system" as used today?

What I am requesting is exactly when the racing positions would have been "frozen"?

I am really interested in why some drivers chose to spin out their cars while others continued to race, realizing that the event may be stopped.

Henry

#387 Ray Bell

Ray Bell
  • Member

  • 54,278 posts
  • Joined: December 99

Posted 21 September 2007 - 22:58

I think that would be a life-or-death type of decision...

Self preservation often overcomes the desire to win.

#388 bobdar

bobdar
  • Member

  • 103 posts
  • Joined: January 00

Posted 22 September 2007 - 00:05

For a better understanding of Henri's description, see the YouTube video at


#389 TrackDog

TrackDog
  • Member

  • 335 posts
  • Joined: August 07

Posted 22 September 2007 - 03:18

Originally posted by HistoricMustang
Do any of the members have information on how "Flagging and Scoring" rules were applied during the 1964 event.

Was it simply at the Start/Finish flag stand or did the speedway have a "light system" as used today?

What I am requesting is exactly when the racing positions would have been "frozen"?

I am really interested in why some drivers chose to spin out their cars while others continued to race, realizing that the event may be stopped.

Henry


As I remember, there wasn't really a "light system" until the early '70's, and it was relatively innefective. The pace car didn't actually pace the field under caution until the mid '70's, and in the years prior to the pacer lights, the field didn't really slow down too much for a yellow. I think they probably consideres the start/finish line as the reference point for scoring positions.

As for spinning in the 1964 event, I would imagine that it was probably involuntary...


Dan

#390 Lotus23

Lotus23
  • Member

  • 1,006 posts
  • Joined: October 02

Posted 23 September 2007 - 19:12

Henry, I concur with TrackDog.

I'm sure there was no yellow light system in place in May 64, and as best I recall the yellow flag was displayed at S-F only.

In-car radios? Perhaps. The first ones began to appear around that time. (In fact, one of the Porsches at Augusta had an in-car radio at the March 64 race.)

#391 Henri Greuter

Henri Greuter
  • Member

  • 4,908 posts
  • Joined: June 02

Posted 24 September 2007 - 07:02

Diving into the books I found another poblication that is worth to quote from.
How about this:


From: HURTUBISE by Bob Gates (1995), ISBN: 0 9627653-5-X

Page 184

Dave was driving one of Mickey Thompson’s radical, envelopebodied, Ford Powered creations, and his presence in the field on race day would prove tragically significant. McDonald, who cut his competitive teeth racing big bore Corvettes on Sports Car Club of America road courses, had endured handling difficulties with the car all month, and was overjoyed just to be in the race.
Just two days before, both MacDonald an Thompson spoke candidly of the difficulties they were experiencing. “The car doesn’t feel right yet,” stated MacDonald. “The front end wants to lift, and I just can’t seem to handle it coming out of the turns.”
With words that now seem eerily prophetic after the deadly drama that transpired on race day, Thompson explained why. “The car was designed for the small, twelve inch diameter tires, but they were banned. And, that’s got my suspension system messed up. The roll centers aren’t in the right place, the mounting points aren’t right. Anything I do to help it will be a compromise, and I’ll never get it right.
But we’re making some aerodynamic changes in the car,” Thompson continued, explaining what he was doing to correct the problem. “I’m trying to control my car with a certain amount of lift. It’s still lifting too much, but I’m trying gradually to decrease it.”


If I understand this correct: the team actually deliberately had the car lift, and thus reduce any downforce there was!!
I know, the state of chassis technology and aerodynamics wasn't that adsvanced yet at the time and they bgan to learn more about it at this time, the Thompson Skates being examples of the forerunners of the new trend.to employ aero.
But making the car lift at speed on purpose? Whew!!!


I don't know if something like this has been described or told anywhere else? Anyone recognize such quotes and statements from other publications.
As for the accuracy of the book in matter. Gates also wrote about 80 gallons of fuel in MacDonalds's car. Thar rumor is taken over by a number of writer over the years.

Henri

#392 TrackDog

TrackDog
  • Member

  • 335 posts
  • Joined: August 07

Posted 24 September 2007 - 07:43

According to Denny Miller's book, THE CLOWN PRINCE OF AUTO RACING, Thompson claimed to have the car sorted out by Carb Day...this quote seems to contradict that, unless it was made 2 days after Dave qualified. It seems obvious that Thompson was grasping at straws, at least by today's standards, when he was trying to induce lift...but aerodynamics was still a very black art in 1964.

I wonder just how much a rear wing would have helped this car...


Dan

#393 Henri Greuter

Henri Greuter
  • Member

  • 4,908 posts
  • Joined: June 02

Posted 24 September 2007 - 08:05

Originally posted by TrackDog
According to Denny Miller's book, THE CLOWN PRINCE OF AUTO RACING, Thompson claimed to have the car sorted out by Carb Day...this quote seems to contradict that, unless it was made 2 days after Dave qualified. It seems obvious that Thompson was grasping at straws, at least by today's standards, when he was trying to induce lift...but aerodynamics was still a very black art in 1964.

I wonder just how much a rear wing would have helped this car...


Dan


Yes that's true. Forgot to make that link about the days.
Seems that there is a lot of cantradiction in when and what was achieved, some positive pep talk in order to downplay the troubles likely involved as well.

O don't know about the rear wing by the way. if the rear end became even more grippy courtesy the wing, and with the front end being so loose already....
I thing that with that nose, the car needed a airdam front spoiler to giuide the air around the wheels insted of diricting the air under the car instead.
Ir vestigial front wings.

I think that one could say about the application of aerodynamics that most of it was based on reducing wind resistance and making the car slippery but notpaying attention to the fact that the car had to stick to the ground. I have read a story about the 1964 Ford GT40 (1964 as well....) that cmputers had designed the most slippery shape imaginable but since the computer wasn't told that the opject had to keep its wheels to the ground and stay on the grond, it was low drag for sure. But unstable at speed and willing to take off.

Off topic too: the initial (1969) Porsche 917 was low drag too and whoofully unstable at speed.
When the `Kurz` bodyworrk was invented, the drag was increased dramatically to levels mr Piëch balked about. But since the car finally had solid grip on the track and a good roadholding and handling at last as well, thet finally made people realize that extreme streamlining at the expence of grip and roadholding doesn't alaways allow faster laptimes compared with a high drag car.
Something yet to be learned in 1964....



Henri

#394 McGuire

McGuire
  • Member

  • 9,218 posts
  • Joined: October 03

Posted 24 September 2007 - 10:29

If the car had a problem with front lift at speed, the addition of a rear wing would surely make it worse.

However, I do not believe that front end lift was a factor in this crash as MacDonald clearly lost the rear of the car, not the front. And at the exit of the corner, not at the entry.

To me it is unlikely that aerodynamics played a significant role in the incident, since the exit of Turn 4 was/is one of the slowest points on the track. If MacDonald was going to lose control due to front end lift at speed, that would occur at the end of the straightaway when attempting to turn in, where the car's need for front grip is at maximum. Not at the exit of the corner, where the car is traveling at a considerably slower rate.

In other words: if MacDonald's car had enough front aero grip to make it through the entry to Turn 4, it surely had enough to make it through the exit.

Thompson's quoted remarks about his attempts to induce lift are not the least bit unusual, only his mode of description. Just as true today as it was then: When tuning the car's aerodynamic balance front/rear we are just as likely to subtract downforce from one end as to add downforce to the other end. In terms of the car's aero balance, which is far more important to the car's handling than its total downforce or lack thereof, "subtracting downforce" and "inducing lift" are exactly the same thing.

#395 McGuire

McGuire
  • Member

  • 9,218 posts
  • Joined: October 03

Posted 24 September 2007 - 10:39

Originally posted by Henri Greuter
With words that now seem eerily prophetic after the deadly drama that transpired on race day, Thompson explained why. “The car was designed for the small, twelve inch diameter tires, but they were banned. And, that’s got my suspension system messed up. The roll centers aren’t in the right place, the mounting points aren’t right. Anything I do to help it will be a compromise, and I’ll never get it right."


To me, there is the key to the car's handling problems.

#396 Henri Greuter

Henri Greuter
  • Member

  • 4,908 posts
  • Joined: June 02

Posted 24 September 2007 - 10:41

Originally posted by McGuire
If the car had a problem with front lift at speed, the addition of a rear wing would surely make it worse.

However, I do not believe that front end lift was a factor in this crash as MacDonald clearly lost the rear of the car, not the front. And at the exit of the corner, not at the entry.

To me it is unlikely that aerodynamics played a significant role in the incident, since the exit of Turn 4 was/is one of the slowest points on the track. If MacDonald was going to lose control due to front end lift at speed, that would occur at the end of the straightaway when attempting to turn in, where the car's need for front grip is at maximum. Not at the exit of the corner, where the car is traveling at a considerably slower rate.

In other words: if MacDonald's car had enough front aero grip to make it through the entry to Turn 4, it surely had enough to make it through the exit.

Thompson's quoted remarks about his attempts to induce lift are not the least bit unusual, only his mode of description. Just as true today as it was then: When tuning the car's aerodynamic balance front/rear we are just as likely to subtract downforce from one end as to add downforce to the other end. In terms of the car's aero balance, which is far more important to the car's handling than its total downforce or lack thereof, "subtracting downforce" and "inducing lift" are exactly the same thing.



Now here's a puzzle to think about.

The car lifted at speed.
But short before the spin begon, Dave was very close behind the car in front of him.
Now, did being close to his forerunner add to the aerodynamic instabillity or, being denied of a full "Load of Air" in front of him, did he have by chance more grip at the front because of having less lift?

A situation totally opposit with todays cars I believe!


Henri

#397 TrackDog

TrackDog
  • Member

  • 335 posts
  • Joined: August 07

Posted 25 September 2007 - 10:29

Originally posted by Henri Greuter



Now here's a puzzle to think about.

The car lifted at speed.
But short before the spin begon, Dave was very close behind the car in front of him.
Now, did being close to his forerunner add to the aerodynamic instabillity or, being denied of a full "Load of Air" in front of him, did he have by chance more grip at the front because of having less lift?

A situation totally opposit with todays cars I believe!


Henri


I'm not sure Dave was in a position behind Hansgen's car that would have allowed this scenario to take place...he'd have to be directly behind the car to get enough of a "draft" for something like a "no-lift" situation to occur. As I understand the sequence of events, Dave was almost beside Hansgen coming out of the turn, and travelling about 10 mph faster. He drove down inside Walt, who couldn't see him; and Walt moved down on him, unwittingly. MacDonald had to veer to the left suddenly to keep from hitting Hansgen, and the sudden swerve broke the rear end loose. It could have had something to do with the rollcenter of the suspension, the weight transfer of the car during the direction change [which the full fuel load certainly exacerbated], the "bump" that A.J. Foyt mentioned...or a combination of things. Air currents may have also played a factor, I guess...I'm no engineer or aerodynamicist...these are just guesses.

It seems that the time to ban the 12-inch tires would have been AFTER the race, not before...


Dan

#398 Ray Bell

Ray Bell
  • Member

  • 54,278 posts
  • Joined: December 99

Posted 25 September 2007 - 12:31

They were banned after the race...

After the 1963 race.

#399 Henri Greuter

Henri Greuter
  • Member

  • 4,908 posts
  • Joined: June 02

Posted 25 September 2007 - 14:00

Originally posted by Ray Bell
They were banned after the race...

After the 1963 race.



Makes you wonder exactly when.
If the news would be out shortly after the race then Mickey must have had enough time to rebuilt the cars and/or design new versions of it but with the larger tires.
Or did he neglect the effects too long, underestiiated them, whatever?
If I give him the benefit of the doubt then the ban on the 12's was done rather late, leaving himwith not enough time to deal with the situation properly.

Henri

Advertisement

#400 Henri Greuter

Henri Greuter
  • Member

  • 4,908 posts
  • Joined: June 02

Posted 25 September 2007 - 14:06

Originally posted by TrackDog


I'm not sure Dave was in a position behind Hansgen's car that would have allowed this scenario to take place...he'd have to be directly behind the car to get enough of a "draft" for something like a "no-lift" situation to occur. As I understand the sequence of events, Dave was almost beside Hansgen coming out of the turn, and travelling about 10 mph faster. He drove down inside Walt, who couldn't see him; and Walt moved down on him, unwittingly. MacDonald had to veer to the left suddenly to keep from hitting Hansgen, and the sudden swerve broke the rear end loose. It could have had something to do with the rollcenter of the suspension, the weight transfer of the car during the direction change [which the full fuel load certainly exacerbated], the "bump" that A.J. Foyt mentioned...or a combination of things. Air currents may have also played a factor, I guess...I'm no engineer or aerodynamicist...these are just guesses.

It seems that the time to ban the 12-inch tires would have been AFTER the race, not before...


Dan


Dan,

I always understood that he was short behind Hansgen and was closing in so fast after coming out of the turn that he should have rear ended Walt had he not made the move to the left.
But I am not aware of any film footage existing (and available to the public for watching) of the cars coming out of the turns in which Dave was not spinning already.

That film footage taken from the air could answer that question.
But where is it?

Henri