Parachute Issue Number 1! (1 Viewer)

[none]

Brakes on all four wheels were mandated many years ago on funny cars for safety reasons.

 

[DrRocket]

The issue I see with front brakes on dragsters is the front tire contact patch. With those skinny wheels on the front of dragsters, I don't really see front brakes on them being particularly effective, especially at higher speeds. Might even take away some steering if they lock up. Floppers have a much larger contact patch, so front brakes make sense there. Now if the NHRA were to mandate front wheels the same size as F/Cs, it might make some sense. Sure would look "funny" though.

 

[Nitro Jim]

With Scott's engine explosion blowing the back half of the car facing the ground (which deployed the 'chutes) it is no wonder that they got tangled in the wheelie bars...

 

[Chad]

how about a titanium bracket that extends behind the body to hold the packs. Cables could still be attatche to the body so they would deploy if the body comes off, but it would maintain the angle of attack for the chutes even if the body is dislodged.

On the subject of braking, how about a reverse pressurized brake system (like a semi trailer, removal of pressure applies brakes). You could use a thermostatic valve(ala sprinkler system in a building) mounted between the driver and motor. In the event of an engine explosion, it would remove pressure from the system and apply some sort of braking pressure to the car. The same system could also deploy the chutes

 

[sammi]

Why not mount the chutes out on the end of the wheelie bar?

Mark

 

[Nunz]

I'm not sure if this has been mentioned, but does anyone pay attention to when the chutes actually come out on these cars? To me, it looks like the PS cars have the chutes coming out as they are crossing the stripe. The fuel cars seem like they go another 1/8 mile before they come out. Since the fuel cars eat up real estate at such an incredible rate, you would think that they would have them open as they approach the sripe like the PS cars. I may be way off, it just seems that way when I watch.

 

[Bmoy]

Why not mount the chutes out on the end of the wheelie bar?

Mark

That may work, but I really don't think that it would, because of: A) How low the wheelie bar is. and B) how weak the connection would be to the chassis/body. I might be wrong about B), but not about A. I still like the way that the Force cars' chutes work. They seem to do a good job. Everything can always improve, but is it practical? The more complicated it is, the more prone to failure it can be. I would be curious to know all of the ramifications of all of the new fangled systems that are being suggested.

 

[Bmoy]

I'm not sure if this has been mentioned, but does anyone pay attention to when the chutes actually come out on these cars? To me, it looks like the PS cars have the chutes coming out as they are crossing the stripe. The fuel cars seem like they go another 1/8 mile before they come out. Since the fuel cars eat up real estate at such an incredible rate, you would think that they would have them open as they approach the sripe like the PS cars. I may be way off, it just seems that way when I watch.

I agree the PS always pull the chutes really fast. Is that the driver, or system?

 

[clwill]

I agree the PS always pull the chutes really fast. Is that the driver, or system?

The driver. I think the reason fuel cars seem to be so "delayed" is that they're going 100mph faster when the finish line camera shows them -- I think the drivers do the same thing. Del Worsham has said he pulls the chutes when he enters the speed trap at the top end, a full 60+ft before the finish.

 

[PJ]

A year or two ago some teams were having trouble with the chutes not coming out (maybe Capps) they had to reconfigure the placement in order to get it to work right

 

[*******]

I work at the track when the promods come to town and race and I know of a couple of guys who have their chutes on timers." X " amount time into the run the chute is automatically deployed come hell or high water.

The fuel guys could do the same couldn't they?

 

[Bmoy]

well, what about pedal fests? If you allow, say, six seconds for a pedal fest, it's too long for a normal run.

 

[Nitrohelper]

If Scott had just one parachute blossom all of this would be academic right now!

That's not quite correct ,the engine continued to run in the shut-down because the #3 intake port blew out, and the front of the manifold at the burst panels was gone. The data logger showed that it was still running on engine oil. This also why the fire was so intense.

 

[*******]

well, what about pedal fests? If you allow, say, six seconds for a pedal fest, it's too long for a normal run.

If all the timers were set the same. Say 4.9 seconds or whatever, then if you had a pedal fest they would still be equal with both of them pedaling across the finish line with their chutes out. I bet the crowd would love that.

If one pedals and the other doesn't have too. The chute coming out early is a non factor because he was going to loose anyways right? Just throwing a suggestion out there. Didn't say it was foolproof.

 

[Darryl]

If any one dvr'ed Scott's Accident his chute lines got tangled in the wheelie bar and was all wrapped up. And you know the rest.

The question I have is about Chutes and Brakes is on fuel cars is ?

In a FC the Chute lever is on the body up above the head. But the brake is in the right hand as well...But still why can't they put Perhaps an extra foot brake in cars ? .../QUOTE]

I've always had a problem with the driver in a 300+ mph rocket sled having to take a hand off the steering wheel and attempt to find the parachute release levers. Many moons ago a friend of mine built a combination brake handle and chute release. It was called the 'Sure Chute' and it worked by having a spring inside the brake handle that was compressed when the release was pushed down into the tube. There was a 1/2 to 3/4 inch lip around the top of the release and a hooked lever held the release in the cocked position. The bottom of the sprung release had the chute release wire attached. As the driver grabbed the brakes he squeezed the trigger and that released the spring that in turn released the parachutes. The driver didn't have to make two motions and even when he got into trouble he could grab the brakes and fire the chutes. Neat device but like all racers of that era most felt uneasy with something 'different'. That deal really did work well with hand brakes.

 

[ozfuel]

Good discussion, I've got 2 questions :-
1 - Since the problem seems to be one of the chutes got caught up in the wheelie bars, is it feasible to enclose the wheelie bars ? I've seen guys in the slower classes tie a window net on them to stop this. Enclose them in carbon fibre - not sure if this would create a tunnel effect and upset the aero of the cars.
2 - Not sure if it's my eyes or not, but have the front tires on TF cars gotten bigger this year ? Not as big as the FC's, but definately wider than in years gone by.

2A - really like that suggestion about mounting the chute on the wheelie bar but that would have to be some strong mounts to combat tire shake.

Mark.

 

[magnethead794]

Jerry:

That's not quite correct ,the engine continued to run in the shut-down because the #3 intake port blew out, and the front of the manifold at the burst panels was gone. The data logger showed that it was still running on engine oil. This also why the fire was so intense

One quick question- where is this information revealed at? While it supports theory, i'd liek to know.

Darryl:

I've always had a problem with the driver in a 300+ mph rocket sled having to take a hand off the steering wheel and attempt to find the parachute release levers. Many moons ago a friend of mine built a combination brake handle and chute release. It was called the 'Sure Chute' and it worked by having a spring inside the brake handle that was compressed when the release was pushed down into the tube. There was a 1/2 to 3/4 inch lip around the top of the release and a hooked lever held the release in the cocked position. The bottom of the sprung release had the chute release wire attached. As the driver grabbed the brakes he squeezed the trigger and that released the spring that in turn released the parachutes. The driver didn't have to make two motions and even when he got into trouble he could grab the brakes and fire the chutes. Neat device but like all racers of that era most felt uneasy with something 'different'. That deal really did work well with hand brakes.

I agree- they should have a secondary chute release on a second handle attached to the brake handle. As was demonstrated in one engine blowup, the body buckled up but not off and the driver (scelzi i think?) couldn't reach the chutes.

Mark:

1 - Since the problem seems to be one of the chutes got caught up in the wheelie bars, is it feasible to enclose the wheelie bars ? I've seen guys in the slower classes tie a window net on them to stop this. Enclose them in carbon fibre - not sure if this would create a tunnel effect and upset the aero of the cars.

Look at a rolex series, Koni series, ALMS, or LMS GT car, and they have a diffuser at the rear of the car ( http://autodrum.com/img/media/wallpapers/chevrolet_corvette_c6_r_2005_03.jpg , Diffuser (automotive) - Wikipedia, the free encyclopedia ) to help organize and equalize the airflow.

However, for wheelie bars, enclosing them would create lift as the air hit the piece angled down. But since funny cars usually end up with the nose planted to the asphalt like an alaert hunting dog, that may be a non issue, and same with a rail. again, only wind tunnels could confirm this.

So the only "safe" way to do it would be indeed to put netting across the back- window screen wouldn't work, but something similar to a window net would work.

 

[Draw 3D]

Here's my .02 cents worth.

Have the fuel shut-off handle on the hand brake also pull the chute cable, one action does both.

Move the chute mount from the body to the chassis, it could still be in the same place but instead of being affixed to the body, have it attached to supports coming from the puke-tank/body-mount/wheelie-bar tubes.

 

[Jeff]

TF front tires are bigger, but I'm not sure it happened this year or last. Seeing some people in Top Dragster running the bigger tire. I assume it gives more control during braking or during a sudden lift off the throttle . . .

 

[DG]

"Darryl Jackman;152514
Many moons ago a friend of mine built a combination brake handle and chute release. It was called the 'Sure Chute' and it worked by having a strong spring inside the tubular brake handle that was compressed when the release was pushed down into the tube."

Darryl is "right on" with the combination break and release. It worked great! I believe that the late Joe Winters made them.

However, in our "original FC" [see avatar], we had to mount the chutes at the outside back corners of the PU bed, facing straight up, to get clean air and we were only running in the low 200's.

I noticed that JFR cars have the chutes mounted at the far outside of the Mustang body. With the big "garage doors" that the FC's have on the back of the body, this allows the chute to get into clean air quickly.

Before Stroud, in the late sixties and early seventies, there was a SoCal company called TRIFORM that used the three panel canopy and three big shroud lines. Idiot proof. You basically coiled up the lines and stuffed them and the the canopy into the pack. It ALWAYS came out! The system brought the car to a straight and quick stop without a lot of opening shock! Too bad that they aren't around anymore.