Do bad spots really exist?

[KATO33 0]

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you can calculate winds your self. Granted this takes a bit of math and knowledge of formulas but after awhile, you should be able to look at the winds and see any potential problems.

So what the formula and math Newbie wanting to know

Blue Skies Black Death

[webracer 0]

Bad spots happen if you let them, or if you don't .
When I am at a familiar DZ, I will get out where others shouldn't. Many times I have made it back when those in my group, or groups before me didn't (despite being the highest wingloading in the group by a couple points or more). I have never been angry (at the pilot) when I landed off (about 6 times). It is as much my responsibility as the pilot. That said, I have held the door on many occasions when the green light would have meant landing off.
A huge rule every non-student jumper should know is to locate the DZ immediately after opening (preferably before deployment), and get heading in that direction. Get to your holding area, then play around. I turn with harness or rear risers toward the DZ immediately after opening, then start stowing my slider, loosening my chest strap and opening my helmet or removing my goggles. The last thing I do is release my brakes.
Mistakes happen, the best advice I can give on spotting is to learn from the mistakes in the past. If you choose not to, you will be doing a lot of walking and field-packing.

Troy

I am now free to exercise my downward mobility.

[LouDiamond 1]

Here are two worksheets to help you out. If something is unclear feel free to ask. If the attachment doesn't work, I can e-mail them to you. They are WORD docs

"It's just skydiving..additional drama is not required"
Some people dream about flying, I live my dream
SKYMONKEY PUBLISHING

Weather Data Worksheet.doc

Wind Drift Computation Card.doc

[Ron 7]

This is one area...And I am not starting an AFF S/L debate here...that I like about S/L instruction.

The student is under supervision longer....More jumps are made, and it gives me time to teach the student spotting.

It is also a problem with "Otter Babies"...

If I can find a cessna DZ here near Tampa, FL. I am going to take a couple of car loads of "Kids" to the DZ and teach them to spot.

Ron

"No free man shall ever be debarred the use of arms." -- Thomas Jefferson, Thomas Jefferson Papers, 334

[LouDiamond 1]

Here is a better explanation of the big picture of how the formulas come into play with practical ecxercises you can do in order to learn. It's a PPT presentation and I've pared it down as much as I could to try and make it small, I hope it uploads.

"It's just skydiving..additional drama is not required"
Some people dream about flying, I live my dream
SKYMONKEY PUBLISHING

Windrift2.ppt

[LouDiamond 1]

Lets try this again. I took all the transitions out so the bullets should just appear all at once.

"It's just skydiving..additional drama is not required"
Some people dream about flying, I live my dream
SKYMONKEY PUBLISHING

Windrift2.ppt

[377 21]

Really good HARP calc presentation Lou, thanks.

I wonder if there is any EASY way to use a GPS for measuring winds aloft as you fly through them under canopy?

A simple 360 degree turn should show a ground speed peak when you are running directly downwind and a minum when flying directly upwind.

The difference between this max ground speed and the min groundspeed 180 degrees from that direction should give you windspeed... unless I am missing something.

I wish there was a GPS program suitable for cheap hand held units that would let you make a circle and just readout windspeed and direction without the jumper having to monitor and calculate.

377

2018 marks half a century as a skydiver. Trained by the late Perry Stevens D-51 in 1968.

[LouDiamond 1]

On the eTrex Vista GPS you can select ground speed as one of the real time viewable fields on the screen or you can just use speed. It's a given that you will exit up wind if you planned and exited the aircraft correctly and know the azimuth/heading back to the DZ. With that info, you can use the GPS ground speed or speed readout to determine if you are in the optimum location within the windcone based on the MPH readout. Sometimes facing directly back at the DZ is not the best heading to have the canopy on to get the best groundspeed and that heading or hold can change for every given altitude as the wind direction changes slightly, like it does in the real world.

Unfortunately, I am only aware of software that is designed specifically for the military that does all of this and then some, specifically for HAHO and HALO jumps. However, for your application and most civilians, a standard GPS along with an understanding of how to use it in this environment will suffice, in fact, thats how most military's are currently doing it, a simple boat compass and a GPS receiver mounted on a chest board.

"It's just skydiving..additional drama is not required"
Some people dream about flying, I live my dream
SKYMONKEY PUBLISHING

[fred 0]

Just a couple of newbie stories.

At the first jump course, at a Cessna-182 dropzone, every student was dropped (on S/L) on their own pass. The jumpmaster would spot, give commands ("Put your feet out.", "Get out and hang.", "Go!"). After a few jumps of this, they'd say, "Why don't you spot this one." I was nervous, but it wasn't a big deal. With a single pass per student in a cessna, if you get out somewhere near the dropzone, you'll be fine.

Switched to AFF at Skydive Arizona, on Skyvans and Otters, where we followed the light. On one jump, the JM looked out, and asked the pilot to do a second pass (it was probably a 180, but I didn't have the experience at the time to know the difference). That triggered in my mind that (a) you should probably look before you get out, and (b) it's okay to ask for a turnaround.

Back home, at the Cessna DZ, on my Pre-A solo jumps, I was last out. After watching the first 3 solo jumpers go out, I spotted, and I was farther away than I'd ever been from that DZ. I asked the pilot to do another run. He did a hard rudder and bank--probably hoping I'd fall out--and said, "What's wrong with that?" But did the 180. After further jumps, I'm pretty sure he was right. I was way underestimating how far I can fly to get back.

Fast forward a few years after a break, after getting a refresher and jumping solo again, I do my first two-way (since the break, so no beer, right?). I watch the first two get out, and then start my count to 7 for separation, before I start climbing out (winds were a little high). I failed to take into account that 'time taken to climb out' is part of that 7-second delay. Since I am somewhat clumsy, and since I probably count slower under stress, we were pretty far out before we actually left (though, I still think the initial spot was probably long and crosswind). Still managed to make it back in time for a downwind, crosswind, and upwind landing. But pilot and other jumper say that they were yelling, "Go!" though I didn't hear them.

My point? None really. But these are some of the lessons I've had in learning how to spot.

[Baksteen 84]

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pilot and other jumper say that they were yelling, "Go!" though I didn't hear them.

Yes, it's funny how people yelling "go" always seem to impair my sense of hearing as wel as slowing me down physcally.

Translation: People yelling "go" even if you DO hear them:
Fuck those lemmings. You seemt o be doing fine.

"That formation-stuff in freefall is just fun and games but with an open parachute it's starting to sound like, you know, an extreme sport."
~mom

[DrewEckhardt 0]

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Have heard plenty of people now refer to being given a 'bad spot' and landing off as a result... just wondering what people think about this, as I have always taken it as my responsibility to decide if I can see the DZ before I jump.

My main reason for asking, is that on the occasions where I was not happy to jump... people have been upset at having to fly round or wait for me.

Have seen alot of people herd out of the plane like sheep without knowing where they are! What dya reckon? Should I hold people up?

When there are strong head winds at various altitudes and the King Air (which is not a slow plane) is basically sitting there (we got great winds aloft in Colorado coming over the continental divide) you shouldn't get out until well past the drop zone regardless of when the inexperienced pilot turns on the green light (with a bunch of fuel tanks, two engines, and a good glide ratio he's going to make it back no matter what happens).

When the same pilot doesn't turn on the light until the plane is over the top, there aren't significant winds, the first group takes forever to climb out, and the 8 2-ways after it take a while you aren't going to land in unless you're jumping a wing suit or open really high.

You need to learn what the land marks are, how bad landing out is in terms of safety + neighbor relations + actually getting back to the drop zone within the hour, what the winds are, and look outside the plane.

Then do what you think is best.

Taking a cellular phone in a jumpsuit pocket is DEFINITELY a good idea when you guess wrong and end up too far away. It would suck to land out with issues and have to wait for a farmer to find you the next day.

Buying beer on a regular basis is DEFINITELY a good idea. It'll keep people happy with you when you are wrong.

[riggerrob 558]

"... All DZs have land marks that are used at altitude. Ask a local what they are and become familiar with them. At a minimum look at the big photo most DZs have of the DZ and surrounding area. You can still look out windows so you stay oriented and have an idea of where you are in reference to the DZ...."

.......................................................................

Good point!

I always advise young jumpers to keep their eyes outside the airplane for the last two minutes before they open the door.

[MikeJD 0]

Yes, bad spots exist.

The mystery is why they happen so much more often to people with no sense of canopy control.

[SethInMI 145]

Holy thread bump.

I didn't figure it out until the mention of the C130 at the WFFC, then it's welcome to 2002.


To comment on technology, GPS, etc: I believe we have the tech on an Iphone or other GPS equipped smart device to program a few things:

1. Best glide indicator. Shows what the glide on your canopy (or wingsuit) is. With an internet enabled smart phone, it could download the WA forecast to come up with an instantaneous "true estimated" glide. A light or beep could help you fine tune your inputs (arms and legs in a wingsuit, risers and toggles under canopy) to get the best performance.

2. From that, a "you are not going to make it" signal. Based on GPS, using the DZ location, your location, and at your current groundspeed and descent rate, you are not going to make the DZ. Give more brake input and the signal changes to "you are going to make it." This would be great to have to help make the "I am going to have to find an out" decision as soon as possible. Of course this signal could still trip you up, as lower level winds could be at a different direction or magnitude, but again you would have a helper to signal that to you ASAP.

I assume from Campos posts that the military has both these things already (and has had for many years), but the software and hardware to do these things is pretty much now commercially available, just needs some developer to put it together, and stick it on a device that can be worn or beeped in the ear or flashed by the eye.

Both of these tools will come out someday, and when they do they will help someone avoid an out landing or have a safer out landing and maybe save a life.

It's flare not flair, brakes not breaks, bridle not bridal, "could NOT care less" not "could care less".

[LouDiamond 1]

A few comments on your points. I am by no means trying to stifle anyones ideas/efforts but having real world experience with this particular technology, there simply are some limiting factors that make some of this un-doable at this time.

Yes, the military does have a system that can do a good deal of what you posted and then some but it is also has it's limitations and uses. Plus the military does things a bit different than what an average skydive operation does when it comes to dropping jumpers. Enough that said system would be useless to a civilian skydiver.


To answer your points:

1. Glide ratio can be seen on some handheld GPS receivers now, the etrex vista is one of these. Unless you know how to use this information while under canopy or are collecting it for testing purposes, it's pretty useless to a civilian skydiver you should instead be looking at the sky and canopy traffic around him and not at a GPS screen.

Civilian operations don't have access to winds aloft data that covers every thousand feet up to jump altitude like military operations do. So using the WA data typically found at civilian operations to determine a "true estimated" glide is an exercise in futility. Even with the military's ability to use wind data for every thousand feet, it still can be prone to error since the wind is constantly changing. The only sure way to do this is to drop a wind sonne that transmits the real time wind data as it descends back to the aircraft where the information can be used appropriately. Again, the military has this capability but its a pain in the ass to use and the equipment is beyond most peoples or DZs budgets.

The other issue is cell phone coverage. As much as I like some of the GPS cell phone programs out there, it can have degrees of error that are horrendous compared to average handheld GPS receivers, especially when it relies on cell phone towers to help pinpoint its location, and thats while on the ground, I won't even get into altitude errors. The other issue is that cell phone coverage usually drops off at/around 10k feet AGL.

Quite frankly, using a cell phone to do this type of GPS receiver work in the sky at skydiving altitudes is a hopeless endeavor at best and not something I would trust over my own judgement. Using said ideas on the ground is a different story as there are less cell phone issues to come into play.


2. Yes, it already exists and does all of that, but again, it is very specific in its design and the dollar amount is prohibitive and more importantly, it wouldn't be valuable to the average civilian skydiver.


The only instance where it would be applicable in a civilian skydiving scenario would be on cross country jumps. But you need all of the above mentioned info to utilize it effectively. I just don't see it being practical or safe on a cell phone platform.

"It's just skydiving..additional drama is not required"
Some people dream about flying, I live my dream
SKYMONKEY PUBLISHING

[mjosparky 3]

I think in the long run you would do better to concentrate on flying you canopy, avoiding collisions with other canopies and locating a safe place to land. Leave the tech. toys for when you are on the ground.

Like Scott said, if you could make it work by the time you got the data you would not need it.

Sparky

My idea of a fair fight is clubbing baby seals

[SethInMI 145]

You are correct Scott, I don't think a cell/smartphone platform is going to be the answer.

And yes, the WA info is not probably good enough to do much with, but a "true estimated" glide is not really required for the two purposes I proposed.

I am not envisioning a "moving map" style display while under canopy. Just a few lines of text on a display.
Line 1 says: "glide 2.0 "
Line 2 says: "dz arrival 1200 ft" or "dz arrival -400 ft"
if line 2 is under 500 ft, perhaps you should change your canopy inputs or find a new landing area.

As far as Sparky's comment about being distracted under canopy, I would expect this sort of device would be used like a canopy pilot uses an altimeter now, quick periodic checks only. And really it would only be used when trying to answer the questions "Can I make it back" or "what do I have to do to make it back" once this question has been answered, this information is as useful as my Neptune's descent rate info, that is, it is kinda neat, but not something that a pilot will use on a regular basis.

I still think someone someday will integrate GPS into a Neptune/Visio device, and it could display (or through lights and sounds) that info. And I do think this will be helpful. But even so it may still fail to sell, if it is too hard to set up or use, too expensive, too bulky, or too unreliable etc.

It's flare not flair, brakes not breaks, bridle not bridal, "could NOT care less" not "could care less".

[LouDiamond 1]

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I am not envisioning a "moving map" style display while under canopy. Just a few lines of text on a display.
Line 1 says: "glide 2.0 "
Line 2 says: "dz arrival 1200 ft" or "dz arrival -400 ft"
if line 2 is under 500 ft, perhaps you should change your canopy inputs or find a new landing area.

In order to do that, you need the winds as I described above PLUS you need to exit in the wind cone. Civilian skydiving jump runs don't always put every jumper out in the ideal wind cone(hence this topic). Line1, GR, would help them identify which orientation of the canopy provided the most push if they were in the wind cone. If they are anywhere near the edges or outside of it, it's really a moot point. Line 2 is good info but based on my experiences with the system I've used that does this, that information can be misleading. Case in point, I've exited at 25k ft AGL on a HAHO (farther away from the DZ than anyone typically does) and the line 2 info clearly stated that I would not make it back to the DZ given the current winds at that altitude. However, I continued on heading back to the DZ. Given that info, one would assume that I should start looking for an alternate landing area. However, as I continued back to the DZ and continued to descend, as expected, the winds changed and the readout actually improved. However, I had additional information on my screen that allowed me to make the determination to continue.

Conversely, I've also had it say I'd make it back and arrive at "X" altitude while at a higher altitude only to get to a lower altitude and have it say I would not arrive. Again, I had additional info on my screen that allowed me to make an educated decision. My point in all of this is that the line 1 and 2 info you speak of alone is not enough to really be helpful, in fact it could be misleading in either direction and give an erroneous readout to the user.

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I still think someone someday will integrate GPS into a Neptune/Visio device, and it could display (or through lights and sounds) that info. And I do think this will be helpful. But even so it may still fail to sell, if it is too hard to set up or use, too expensive, too bulky, or too unreliable etc.

Already been done. Alti-2 developed what was known as the Titan several years back that integrated a GPS and a visual readout in front of the jumpers eye. It ran into some issues but it's the farthest I've seen a civilian device developed that was actually used on a limited prototype basis.


What you (and others)propose to do is a more difficult task to achieve than you probably realize, especially on a cell phone.

"It's just skydiving..additional drama is not required"
Some people dream about flying, I live my dream
SKYMONKEY PUBLISHING

[robskydiv 0]

What happened to the time that one could release a wind drift indicator over the spot at about 3,500ft.?

[Harmless 0]

I do it all the time for first load... usually from 2500ft though.

"Damn you Gravity, you win again"

[skybill 19]

Hi P-pod,
As long as there will be Skydiving with more than (2) people exiting an aircraft in flight, there will be differences of opinion over the spot. Some 45+ years ago out of a Cessna 172 at Hammond Airport La., 3 jumpers were getting in the plane and Henry Connor from New Orleans Skydivers grabbed the wind drift indicator (the long yellow crepe paper streamer to you newbies) and said,"I'm Spotting!!" Philip R. "Cappy" Connors from Louisiana Skydivers, Baton Rouge said,"That's O.K. Henry, I know how to Track!!" Don't worry though, no matter where you exit the aircraft, you are still directly above the center of the earth!!!

SCR-2034, SCS-680

III%,
Deli-out

[robskydiv 0]

I've landed in a cornfield before & a cow pasture. Yeah, they exist.

[jumpwally 0]

All true but basically splitting pubic hairs due to the fact that your example represents less than 1-2 % of all jump runs in a given year,,,

smile, be nice, enjoy life
FB # - 1083

[popsjumper 2]

One bad spotter can hose a whole planeload of lemmings!

My reality and yours are quite different.
I think we're all Bozos on this bus.
Falcon5232, SCS8170, SCSA353, POPS9398, DS239

[mjosparky 3]

Most bad spots are caused by the earth rotating after exit.

Sparky

My idea of a fair fight is clubbing baby seals