Jumpers on RADAR

[LearningTOfly 0]

Random wondering here... can ATC pick up skydivers on Primary radar?

I've heard that they can pick up trucks on a highway- and I think I've heard that they can pick up flocks of ducks/ geese. How about divers?

[BillyVance 34]

Yes, ATC apparently have picked up the large CRW formations in Lake Wales during the past couple of world record attempts... That 85 way they recently built is bigger than a 747, but damned if I know what the blip for the CRW formation looks like... I'm sure they wonder why the fuck is it only going 25 mph??

"Mediocre people don't like high achievers, and high achievers don't like mediocre people." - SIX TIME National Champion coach Nick Saban

[skylord 1]

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Random wondering here... can ATC pick up skydivers on Primary radar?

I've heard that they can pick up trucks on a highway- and I think I've heard that they can pick up flocks of ducks/ geese. How about divers?

No, maybe a big way, but not individual divers. Even with a big way, once the primary target is detected, the software logic will prevent the display of the digitized symbol since the ground speed will usually be below 30 mph (I think that's the parameter.)

We pick up trucks and cars as they go by the radar site with a high enough cross section to return a detectable echo. For birds, it would have to be a good sized flock, gaggle, etc......

Bob

Bob Marks

"-when you leave the airplane its all wrong til it goes right, its a whole different mindset, this is why you have system redundancy." Mattaman

[MrBrant 0]

how about a big-way RW, going 100ish mph (down)?


Edit: oh, I see you typed Ground speed.
how about a big birdman flock?

[akjmpplt 0]

Approach calls jumpers as traffic for me quite often. This is after they've opened.

SmugMug

[FrogNog 1]

You could wear a passive radar reflector and guarantee ATC can see you.

-=-=-=-=-
Pull.

[tdog 0]

For some silly reason I feel violated that my body would be able to show up on your approach radar...

Anyone got one of those stealth jumpsuits?

[greybeard 0]

I seem to recall that a few years back, pieces of ieght launched out of Perris and ATC ALB called the pilot and initiated action against him for jetising from a/c. The para gear actualy showed a blip.

Anyone recall the particulars of this?

[diverds 0]

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Approach calls jumpers as traffic for me quite often. This is after they've opened.

Same here.

Skydive Radio

[sundevil777 102]

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the software logic will prevent the display of the digitized symbol since the ground speed will usually be below 30 mph

So balloons would not register? I would think ATC would be interested in them.

People are sick and tired of being told that ordinary and decent people are fed up in this country with being sick and tired. I’m certainly not, and I’m sick and tired of being told that I am

[shall555 0]

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Random wondering here... can ATC pick up skydivers on Primary radar?

I remember once in around '77 or '78 the controller, on a slow Sunday morning, telling the pilot he'd tell him when the jumpers left.

Sure enough, about 2 seconds after one guy exited, the controller told the pilot.

Amazing that they can see reflections from harness hardware on those things.

Of course, today, software may filter out the 'junk' better.

shall

[JYorkster 0]

I have tracked a Tandem easily with a military radar. I would expect the same for a solo jumper. Of course as others have said, it depends on how the radar system is set up. It also takes a skilled controller to know what to look for, and it helps to know when/where to look.

Rock

[skylord 1]

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Approach calls jumpers as traffic for me quite often. This is after they've opened.

OK, but is that based on radar returns or the report from the pilot that jumpers were away? Was it "Traffic, 11 o,clock, less than a mile, a jumper in freefall" or "Jumpers in your vicinity"?

We can't see individual jumpers, and as to balloons, we don't see them either unless we are told in advance where they are. Even then we don't "see" them, we rely on NOTAMs or PIREPs.

Bob

Bob Marks

"-when you leave the airplane its all wrong til it goes right, its a whole different mindset, this is why you have system redundancy." Mattaman

[ltdiver 3]

A couple of years ago I was filming a record attempt by "Pieces of Eight" out of the SkyVan at Perris. ATC called up to Rob, the pilot, that there was traffic right below him! He looked, then laughed. It was the formation of metal arms and legs that was picked up on radar.

ltdiver

Don't tell me the sky's the limit when there are footprints on the moon

[justinb138 0]

So if I wrapped myself in aluminum foil and then made a jump, would I show up on radar then?

[Eule 0]

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I've heard that [ATC radar] can pick up trucks on a highway- and I think I've heard that they can
pick up flocks of ducks/ geese. How about divers?

I know that _weather_ radars can pick up flocks of birds. See for example
http://www.physics.brocku.ca/faculty/black.html, http://www.weathernotebook.org/transcripts/1999/07/26.html,
and http://rsd.gsfc.nasa.gov/goes/text/weather.radar.birds.html . The mpeg on this last page has moved to http://goes.gsfc.nasa.gov/pub/goes/weather.radar.birds.mpg .

This has been mentioned in the thread, but in the front page story about the 85-way CRW formation, it
says that the formation showed up on radar.

In this modern world, if you call the local ATC office and ask, they'll probably assume you're a terra-ist.
But the weather office people seem to enjoy talking to the public about what they do. If you can get
somebody there interested, then maybe on some weekend with clear weather, they can point their
radar at the dropzone and see what they get. I think the weather people are much more free than
ATC is to have their radar scan only a certain part of its rotation, change the elevation angle, play
with the sensitivity settings, etc.

You could probably strap a transponder onto yourself and be sure to show up on the ATC radar. You'd
need to strap more hardware on if you wanted the altitude-reporting feature to work.

I wonder how small of an object the ATC radar can pick out. Once you know that, you can get a
bunch of people that are good at RW to wear tinfoil jumpsuits and do formations that spell rude
words on the radar screen...

Eule

PLF does not stand for Please Land on Face.

[phoenixlpr 0]

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Even with a big way, once the primary target is detected, the software logic will prevent the display of the digitized symbol since the ground speed will usually be below 30 mph (I think that's the parameter.)

How about a wingsuite formation?

[BIGUN 1,438]

About three years ago, Four of us decided to make a HAHO jump over downtown Tulsa and fly back to Skiatook under canopy (about 13 miles). Got out @ 14K and dumped.

Plane headed back. ATC called the pilot and asked him to come back and circle around us until waved off. Seems the ATC guy was catching intermittant blips of us and they wanted to make sure where we were. Our pilot came back back and circled. ATC then started passing SW Airline flights under us at 4K - kewl sight to see under canopy.

Nobody has time to listen; because they're desperately chasing the need of being heard.

[darkwing 5]

In 1974 we were doing night jumps in Star, Idaho, and the controller in Boise asked if we would put some foil in our jumpsuits so he could see us. It apparently worked.

-- Jeff
My Skydiving History

[mr2mk1g 10]

Sounds plausible. My father and friends apparently caused a series of newspaper reports and UFO sightings in post-war Cardiff by releasing dry cleaning bags filled with street gas with a torch battery, flashing light and ball of tin-foil suspended beneath them.

[chuckbrown 0]

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No, maybe a big way, but not individual divers.

I jump at a small DZ about 15 miles from Harrisburg International Airport (Pennsylvania). Our CRW loads are generally never larger than 4 ways. Harrisburg routinely picks us up on radar. For free fallers its probably a different story.

[matthewcline 0]

The Radar at Campbell AAF usually calls the A/C around and tells them we have landed before we do.

An Instructors first concern is student safety.
So, start being safe, first!!!

[tdog 0]

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About three years ago, Four of us decided to make a HAHO jump over downtown Tulsa and fly back to Skiatook under canopy (about 13 miles). Got out @ 14K and dumped.

Plane headed back. ATC called the pilot and asked him to come back and circle around us until waved off. Seems the ATC guy was catching intermittant blips of us and they wanted to make sure where we were. Our pilot came back back and circled. ATC then started passing SW Airline flights under us at 4K - kewl sight to see under canopy.

Funny... Didn't you know you were to wear a transponder and be in contact with ATC under canopy... "Sabre2 170, change heading to 230 and maintain 14 knots, and contact approach at 123.51"

Just kidding.

[bob.dino 1]

You live and learn.

[cappiocat 0]

From what I have seen, the answer is maybe/maybe not. ATC radars often have ways to filter out weak returns to remove clutter and reduce controller work load. I remember having a controller demonstrate to me once, he could adust it to show only those returns that had active transponders or show any primary returns (skin paints). At the skin paint setting, he pointed out a bunch of clutter, a flock of birds, a few hang gliders, and a formation of 4 Air National Guard Fighters. At the highest level of filteration only the lead Fighter showed up since only he had his trasponder on. This was some years ago so I imagine more modern systems have a more refined selection of filters. Having done a fair amount of large CRW, I have occasionally seen the aircraft I had just exited circling the formation at a safe distance. I was told that this allowed ATC to more easily moniter the formations approximate position and altitude using the aircrafts transponder. Skin paints usually do not give altitude information. As for as free fall goes, I would think it would provide a more difficult target. But not immpossible.