Aerodynamic vs. vehicle stabilty

[Cajun Kid]

Maybe I am reading the posts wrong, but it seems some are saying the larger canopy chutes with shorter lines (Drag style chutes) deploy instantly or much faster and hit harder, and those others say the smaller canopy, longer lines (LSR Chutes deploy much slower and hit softer) ??   I am not convinced there is that much difference in time from deployment to "full canopy bloom"  now I truly believe the drag chute is not "instant bloom" and that the LSR is not "slow to bloom"

For your viewing pleasure I have attached a video that will allow you to look and listen as well as replay and stop the clock.  If you do frame by frame or normal speed and watch the video clock or use a stop watch you will notice that  from the time you see the chute deploy, to the time the lines jerk taunt with full bloom it is less than 1 second.  What we do not see is how long from the time I pulled the handle to deployment, or how long it took me to pull the release from the time my brain said now ( I know, it was FAST,, I am previous quick draw and competition shooter, so hand speed is awesome fast, I can draw a six shooter from hands over head position, shoot you in the chest 5 times and re holster in less than 3 seconds. 2.2 seconds If I don't re holster) but who is counting ?  LOL

back to the chute watch the video and look at the pictures and comment, maybe 1 second is slow for a LSR chute with 60+ foot lines. but then again drag chutes are not as instant as you might think either...

CLICK the PICTURE to Launch Video


Still Shots







Charles

[F104A]

I know I'm relatively new in the LSR arena but in 21 years at the salt, I can't remember a chute preventing
a spin. Usually the chute winds up under the car and all wadded up with 10 lbs of salt to carry to the push
truck. If whats-his-name won't consider my methodology for 1/10th of a second, well, to bad. It isn't advice,
just the way I do it and it has worked for me in many many chute deployments. Before I went with the bag
and longer lines, the big chute on a shorter line used to cause the lakester to wiggle from side to side and
poke my toes out of my shoes. Now I don't have that problem and the chute deploys every time and
causes no handling problems. No advice, just the way I like to do it..........Ed

[bvillercr]

In my 22 years on the salt and at El Mirage I usually don't have many problems with the car handling absolutely great.  With the added power in the last couple years and the deteriation of the track at El Mirage I have gotten very sideways.  At Bonneville two years ago I got a little aggressive with the accelaration and while in 2nd maybe 3rd I came up on the power and it took me to the right and I didn't peddle it soon enough. When I do get loose I always clutch the motor and a couple times had to pull the chute.  If I didn't pull the chute I surely would have spun.

[hotrod]

This is what happens if you pull the chute a bit too late.

[jl222]

I know I'm relatively new in the LSR arena but in 21 years at the salt, I can't remember a chute preventing
a spin. Usually the chute winds up under the car and all wadded up with 10 lbs of salt to carry to the push
truck. If whats-his-name won't consider my methodology for 1/10th of a second, well, to bad. It isn't advice,
just the way I do it and it has worked for me in many many chute deployments. Before I went with the bag
and longer lines, the big chute on a shorter line used to cause the lakester to wiggle from side to side and
poke my toes out of my shoes. Now I don't have that problem and the chute deploys every time and
causes no handling problems. No advice, just the way I like to do it..........Ed

  Thundersalt [Celia driving] this year got real side ways [ Glen reported a spin] but she did a heck of a job driving and got the chute out quickly and didn't spin same as Bvillercr above there's two. Fred Danenfelzer uses the same chute as we do on his 385 mph lakester.
 Chutes need to be sized for different cars , weight and speed I just wonder about long lines from the pilot chute.

               JL222

  Actually at Bville chutes are not really needed for the majority of entrants except for getting off the course fast and
emergencys.

     


           

[Cajun Kid]

Jl222,

Not sure if you watched my video ?  On Thundersalts car is he using a LSR chute like mine or the shorter lined Drag type?   

From the almost spin to saving it, looks like the chute was a major factor to keeping the car from going around,, that was most likely because of good driving, followed by quick decision to pull chute, followed by good reaction time in getting chute pulled, followed by chute deploying in good air quick enough, followed by quick canopy blossom.

I would say I listed it in the actual order of importance,  as the by the time you do all of those things in the correct order, the .8 to . 9 second LSR chute blossom to the .5 or.6 drag chute blossom is not as big a deal as one might think, a fast blossom if you don't do everything else quick and correct is not going to help,, just tear up a chute.

That's my thoughts.

Charles

[jl222]

 
Charles...you call that fast? ...Bville could run 40yds in 4.6 sec as a running back in highschool
 Just kidding, those skills could come in handy at times in Fresno :-P

 All this discussion about chute opening time and lenghts got me off my butt to measure the chute, easy as we have not packed it after washing

 Pilot chute line...5 ft
 lines from car to main chute 22 ft and 8 lines
 Size of chute 12 ft

The opening speed might not be instant but its got to be faster than 60 ft lines.

                     JL222

[Cajun Kid]

JL222,

I 100% agree with you that the 22 foot lines are not instant, but would be faster than 60 ft lines.

I do know how long it takes the 60 ft lines to open, does anyone have a clear enough video so we can see shorter lines deploy?

I aslo think that yes 22 foot lines would have to open faster, but one more consideration is the shorter lines ar attached to a larger canopy, and maybe, just maybe the time gained by shorter lines does  not fully translate to faster full blossom since there is more material to open ?  not sure, until a "see" and time the short line chutes in a LSR setting we are all just "thinking"

As for long line LSR chutes,, at least I am glad the photographer at Loring got a decent video for my reference.

Charles

[jl222]

  The chutes don't know were their deployed just watch the drag races.


                  JL222

[Cajun Kid]

  The chutes don't know were their deployed just watch the drag races.


                  JL222

Agree, however.... The go fast drag cars over 200mph are not (or I have not seen them ) using chutes with spring loaded pilot chutes, maybe the sportsman class cars still do, but any cars over 200 that I have seen recently are using launchers ??  I could be wrong,, I will record some runs and play back and report my stop watch and frame by frame findings.

Thanks

Charles

[1212FBGS]

222 holy crap... you throw out a 12 footer at nearly 300!!! that son of a gun must give you a he77 of a yank...
kent

[jl222]

222 holy crap... you throw out a 12 footer at nearly 300!!! that son of a gun must give you a he77 of a yank...
kent

   KENT... I let it slow down for the mandatory pull,but hit both chutes at 275 by accident once, it stopped like he77
but being strapped in tight it didn't hurt.
  Another time the cyl head torched into the water jacket at 265 and blew off the water hose and cracked the water tank, instant fog on windshield ,pulled both chutes and stood on brakes [front and back brakes] course stewart said
''man you sure stopped fast'' I couldn't see were I was going.

          JL222 

[bones]

Here are 3 photos I took at the drags trying to see what the air was doing

/img]less than 100' out. note the verticle string directly behind the rider (the air must be bent)

[bones]

1st photo

[bones]

about 330'   The harley rider was pissed--- jap bike ang girl rider

to end - 135 mph   string goes a bit wonky.
   Bones