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Jumper / Aircraft collisions

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From jumping in the U.S. I know that it is illegal there to jump through clouds, because jumpers have to adhere to the same regulations as VFR aircraft, and thus technically have to remain clear of clouds by a certain margin. In the real world this isn't seen that strict, and jumping with anything between clear skies and broken clouds is common. I have never personally seen intentional jumping through a solid overcast layer, though.

Further I know that at least some people spot for airplanes before jumping and some people (Tom Buchanan for example) are putting a lot of effort into raising awareness for jump operations for the bigger pilot population.

Now I had the chance to jump in Australia for a change and was quite amazed that not only it is legal here to jump through clouds (there is a waiver), but I have seen jump operations commence all day when there where several overcast layers, the lowest down to about 2000ft. Procedure is to fall in place (no tracking, turning points, ...) when in freefall in the clouds and to do slow braked 360's when under canopy in the clouds.

But this still leaves separation from aircraft to be addressed. I was told by a caravan pilot well-known in the jump scene here that the APF has researched prior incidents of jumpers in freefall colliding with aircraft and they allegedly came up with only one accident of such nature, in the U.S. Further they allegedly conducted a study where they ran simulations with jumpers and aircraft and said study came to the conclusion that spotting for aircraft and awareness of such was not necessary, because the chance of them hitting each other was so remote that it is deemed an "acceptable risk".

Now there obviously is a different attitude here than there, altough I suspect there also is less GA traffic here in Australia. Also the airspace structure is different, and parachute drops (almost?) always happen in controlled airspace anyway. But underneath still is uncontrolled airspace where technically an aircraft could fly without need to talk to anybody.

So, this has sparked my curiosity. Are the folks in the U.S. just over-careful and restrict themselves when there really is no need, or are the Aussies reckless in their jumping, or lies the truth somewhere in between?

Who can come up with documented cases of jumpers in freefall a) hitting and b) nearly missing an aircraft?

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If you’ve ever looked out the door of an aircraft while spotting and saw an aircraft on an intercept course to overfly your landing area ask yourself what an “acceptable risk” is. :S I’ve seen GA traffic cross into the DZ’s airspace with canopies in the air or worse opening around it several times. Trust me it’s not something that anyone involved with wants to see again.

"We've been looking for the enemy for some time now. We've finally found him. We're surrounded. That simplifies things." CP

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As you said, in AUS jumping is mostly conducted in restricted airspace. The controller can warn off planes that would intercept the area. In the US jumping frequently takes place in VFR (Visual Flight Rules) areas. In these locations pilots may or may not even be on the radio listening to UNICOM traffic.

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Who can come up with documented cases of jumpers in freefall a) hitting



1. 1980 jumper hit by C-130 and killed
2. 1993 jumper hit by piper cherokee and lived, AC crashed 4 dead
3. 1993 demo jumper hit by biplane circling him and both killed.
4. 2001 jumper exits KA and hits totter in formation flight.
5. 2005 totter hits Gus Wing, Gus died later.\

That is all of them on record.
you can't pay for kids schoolin' with love of skydiving! ~ Airtwardo

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and let me tell you about a near miss
in 1982 Elek Puskas(president of paraflite and now CEO of Airborne Systems)was making his 2000th(?) jump at Ripcord paracenter in NJ. at about 1500'under open canopy, a piper cherokee approached him from behind. the propeller struck his pilotchute and destroyed it,but luckily did not hit Elek's canopy. Documented in parachutist magazine in 1982.

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... and I have seen dozens of near misses in Southern California. The airspace in SoCal is just too busy for a recreational pilot to keep track of all the changes, DZs, forest fires, etc.
VFR pilots cannot be trusted to stay away from DZs in uncontrolled airspace. Most North American DZs are in uncontrolled airspace.

Closest near miss I have seen in Canada occurred when a Mooney blundered into the Pitt Meadows Control zone, without talking to the control tower (illegal). He almost hit a Cessna 205 full of jumpers that was climbing on the down-wind leg of the regular landing pattern. If the Cessna 205 had maintained altitude (like most other small airplanes) we would have collided.

The primary reason jumping through clouds is banned in North America is that back in the 1960s (see history forum) a B-25 bomber dropped some skydivers - through clouds - into Lake Erie and most of them died. An air traffic controller was partly to blame and ATC has tried to avoid repeating that mistake ever since.

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Who can come up with documented cases of jumpers in freefall a) hitting



1. 1980 jumper hit by C-130 and killed
2. 1993 jumper hit by piper cherokee and lived, AC crashed 4 dead
3. 1993 demo jumper hit by biplane circling him and both killed.
4. 2001 jumper exits KA and hits totter in formation flight.
5. 2005 totter hits Gus Wing, Gus died later.\

That is all of them on record.



Two die as skydiver hits glider

ciel bleu,
Saskia

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It appears that most of these accidents happened with jumpers UNDER CANOPY and aircraft. The only confirmed freefall collision seems to be the one with the Cherokee. About the glider accident, I guess at 2000ft the skydiver was under canopy already?

Following the theory of that Australian jump pilot the chance of actually hitting an aircraft in FREEFALL is extremely remote. Near hits or close misses would be more common but still rare. I'd like to see a report of the simulation they ran. He told me they had to put thousands and thousands of skydivers and many planes flying through the same airspace in their simulation to reach unacceptable levels of accidents.

The question is if the simulation was realistic.

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I'll try to stay out of this to some degree because there is no single right answer. To be able to discuss the safety of the Aussie rules one had better know the Aussie rules in detail... which I don't.

There are risks of skydiver / aircraft collisions. The risks are low but accidents can happen. In the world of light plane VFR flying by see and avoid, mid-air collisions happen, and not just in the circuit of airfields.

Aussie regs are at:
http://docs.apf.asn.au/index.php/Cloud_Jumping_Procedures

On that page there's a link to the government regs. Also, there's a spreadsheet with the calculations that you're interested in. Seems like any DZ wishing to get approval for cloud jumping would have to do the calculations.

A quick skim of the regs suggest that extensive cloud can't be around opening altitude; openings are supposed to be well clear of cloud. Drops may for example be prohibited if there's a large clear area between cloud layers, because then a VFR aircraft could be in the gap, not visible to the spotter on the aircraft or the mandatory ground spotter. The Aussie rules have a lot of detail, beyond just "well, you probably won't die."

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It appears that most of these accidents happened with jumpers UNDER CANOPY and aircraft. ...Following the theory of that Australian jump pilot the chance of actually hitting an aircraft in FREEFALL is extremely remote.



Why does it matter if it is in FF or under canopy. Everyone dies just the same.

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He told me they had to put thousands and thousands of skydivers and many planes flying through the same airspace in their simulation to reach unacceptable levels of accidents.



And my Dz probably has 100,000 jumps per year. So is just one colision of a jumper under canopy or in FF with an aircraft "acceptable"
"We've been looking for the enemy for some time now. We've finally found him. We're surrounded. That simplifies things." CP

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IMO hitting an aircraft in freefall has little to do with the prevailing weather conditions in freefall.

It is nearly impossible for the aircraft pilot to avoid collision with something small that is coming from above. They simply wont be able to see you before you hit the aircraft.

As for the jumper seeing the aircraft in freefall, it has a little bit more relevance, but still I would say the chances of the jumper spotting an aircraft below and taking precaution to avoid is very slim. How often does an average skydiver even pay attention to surrounding airspace ? Not very often. To some degree maby at some solo jumps, trackjumps etc..

Under canopy this is a whole different thing and under canopy it obviously has a lot of importance to have VFR conditions.

Dont take me wrong, I do think jumping through thick layers of cloud has a lot of impact on safety, but not because it makes collisions with aircrafts more likely. Personally I would be more afraid of collisions with fellow jumpers..

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If there are gliders around, like there often are at our DZ, weather conditions are VERY important: gliders hang out under clouds! Usually they're not very high (2000ft or so and lower) but sometimes they get up to 4000ft and well above.

ciel bleu,
Saskia

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Really? Do you talk to the people who are this negligent at your DZ?



umm... let me ask you something:

When your doing 4way FS do you honestly take pauses to check the airspace below ?

When someone at your DZ is doing 15 way headdown do you think they are going to keep looking down just in case theres an aircraft under there ?

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>When your doing 4way FS do you honestly take pauses to check
>the airspace below ?

Yes! Before exit at least one of us looks down and in a 45 degree 'cone' around the airplane. I've caught half a dozen airplanes headed into our airspace that way.

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I am an aussie and did 6 jumps last weekend with 100% full cloud cover between about 3-5000 feet. I have always paid attention to the pattern the pilot uses to land the aircraft and am very wary to stay away from that area. We normally land north and i have the option to set up my landing pattern over the runway or over a freeway. I always go for the freeway. I try to stay as far away from the runway as possible. When i jump in full cloud cover i am even more wary of where the plane will be at a certain heights and try to make sure i am no where near his airspace. I dont think that there is a problem with the australian rules. The bottom line is that if you dont feel safe and comftorable to jump in cloudy condition then thats your call and dont jump.

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