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Does anyone have any knowledge or first-hand experience with a slider-down jump from a helicopter? I'm just curious...I would think the air ~100' below the helicopter would still be highly turbulent and could very negatively influence pilot chute and other deployment mechanics. If it's not out of the question, I'd be curious about information regarding the type/size of helicopter in regards to the minimum vertical clearance for safe deployment.

R44 Raven II from the door frame (not skid) rear left
slider down
1.5 sec delay

no issues

If you take a 1.4 sec delay, you could have issues...

That is a good question...I wonder what the opening on a S/L would be like...

Why would ya static line a chopper ?

Did I read the question right?

If ya gonna get a chopper go big

Look at the boys in the Olympics :)

Well let's say you needed to jump out of a chopper low to the ground...where it'd need to be slider-down.

I know about this one...

I'm jumping an R44 in a couple days, although not the same person. My plans are similar.

Well the original question was referring to turbulence below the airship on a short delay....understandably a good question. Then P- says he did a 1.5 sec delay with no problems. I think "issues" is the word he used. Anyway, I was just wondering what the opening would be like if one were to do a S/L, for what ever reason, in reference to the turbulence since it would be < 1.5 sec delay. Is the turbulence or down wash to strong to let the canopy inflate and pressurize? I was wondering since doing a short delay in deep brakes with a strong tail wind on opening can cause "issues".

People have d-bagged paragliders and parachutes from helicopters before. That gets the canopy inflating and opening even closer to the turbulance.

I don't think it will be a problem. After all, the worst thing will be a deformed airfoil that will be pulled down by your weight. And as we all know BASE canopies take very little time to recover to full flight. The only suggestion I would make is to use shallow brakes, so there's a smaller chance of an opening stall. Start higher, like above 300ft :)

In an OGE (out of ground effect) hover, the vortices of the helicopter are nearly straight down, besides at the far tip. In comparison to an in ground effect hover where there would be lots of turbulence. I'll try posting a picture that shows this. However, not sure how much effect this downward wash has on a canopy, obviously much less effect than swirling vortices in an IGE hover.

Edit to add link to picture

https://faasafety.gov/files/gslac/FTB/Helicopter%20Aerodynamics/Fig3-5.JPG

I did slider up Wingsuit from Helicopters before. With big choppers and minimal to no forward speed the downwash is very strong and I can imagine that it could influence the opening of a very short delay. If the chopper has some forward movement I don't think opening is an issue....

Through translational lift ie faster then approx 15 mph airspeed(combined wind and forward motion) it will not be a problem. The vortices act the same as an aircraft moving down and away from the rotor disk edges. As mentioned paraglider dbag helicopters all the time. The low pull in Point Break was a 100' slider down dbag from a helo.

i´ve seen a pc blown under the jumper and coming up again on the other side on a to short delay of a chopper i can´t remember, but i think it was an as350.

 
Last summer we did numerous jumps, slider up and down, using 1 sec delays from 500ft all was good.

Large heli too!

If you pitch shorter than one sec your airspeed is so slow you run the risk of your pilot chute being blown under or around you.

I find the jumps fun enough without looking down at my PC.

Just make sure the chopper is going at least 30 or 40 forward when you exit. It's no big deal if you fall a second to get out of the immediate downdraft. Also I agree with the Robinson R-44 heli since it's blades are elevated on a conning tower, cheapest heli to rent and flies good if the pilot knows what he's doing.