IADS vs Static line

[Trivial_Trekker 0]

hey everyone.
I was just wondering if there are any main advantages or disadvantges to jumping IAD or static line. I ve just start my training and am alittle confused to why some schools prefer different jumping techniques.

So far ive got two IADs under my belt. Hopefully one more this weekend. weather complying

thx

[]DETE

[AggieDave 6]

IAD and Static Line jumps are, for all practical purposes, basically the same instruction. The difference is on how the canopy is deployed. More of a technical difference then one of instruction.

Now if you were wondering the differences between AFF, SL/IAD and Tandem Progression, THAT is a large difference.

--"When I die, may I be surrounded by scattered chrome and burning gasoline."

[Trivial_Trekker 0]

Yea i understand that Tandem, AFF, and IADs are completely differnet methods of training. But i was just wondering if there was a major difference with IADs to Static line.
i.e. IAD produce better opening characteristics, or static line is safer --- just examples, i have no idea :P

thanks for replying though

[]DETE

[Andrewwhyte 1]

After using IADs for over fifteen years I bought into a DZ that dropped a bit over 2000 static line jumpers last year. I was overwhelmed by the hideous opening characteristics of the static line sport rigs. Our line twist rate was at least five times what it is for IADs out of the same aircraft, my students lost or destroyed four altimeters from being hit by the deployment bag and we suffered three malfunctions which, as far as we could tell from the video, were at least contributed to by the out of sequence deployment inherent in a S/L system. To add to that the abrupt snatch force early in the count kept many students from progressing as maintaining an arch through an out of balance (of to one side) pull during a dummy pull is very hard.
Some of these problems can be alleviated by various non factory aproved packing innovations and in some aircraft, raising the strong point high in the aircraft. That is not practical in the Cessna's in common use in North America. The better solution in my opinion was to convert to IAD.
The argument has been made that static line is a more sure way to get 'something' out. To this I call bullshit. The last time I saw a pilot chute in tow on an IAD was over ten years ago.
Static line was developed as a way to deploy soldiers who use round canopies and face the tail after exit. It is still the best method to do this. For sport jumping, however, I don't think it is a very good technique.

[billvon 2,435]

>I was overwhelmed by the hideous opening characteristics of the static line sport rigs.

Note that you are talking about the direct bag method of static line. Pilot chute assist gives openings very similar to IAD, since it relies on a pilot chute to extract the main.

[Speed2000 0]

Trivial Trekker,
Congratulations on your first jumps. Welcome to the sky.

The differences between IAD and Static Line are small compared to the differences with other methods, but they do exist, and they affect the DZO/Rigger/Packer, the Pilot, the Instructor, and the Student in different ways. Let's take a brief look at them in turn:

DZO/Rigger/Packer
On the packing floor, IAD has an advantage over SL in that it more closely follows the KISS principle. On an IAD dropzone, all student gear can be rigged to throw out and kept that way. On an SL dropzone, the student gear will either have to be parsed out: some for static line use and some for throw out (AFF, rental, students on self supervision), or be re-rigged on a regular basis. The DZO either has to purchase additonal gear or simply accept the fact that the day will come, probably sooner rather than later, when a load has to be delayed as a rig is converted from SL to throw out or vice versa. A small point, perhaps, but disconcerting to the nervous SL student watching his/her inctructor/rigger/packer hurredly re-configuring his/her gear five minutes before takeoff. Also, a jump airplane used for static line will need to be painted more often due to line rash (I said the differences were small, right?)

The Pilot
Trades one potential emergency for another. Jumper-in-Tow or pilot chute over the horizontal stabilizer. The risk of either is slight, but the pilot and instructor will need to have thought each contingency through beforehand and incorporate preventative measures (e.g. flaps) into their respective checklists.

The Instructor
Each method has its' own quirks, a lot of the time it boils down to personal preference. Personally, I prefer IAD, but then I do IAD more often. I know other instructors who prefer static line. Preferred seating arrangements, how far out on the strut the instructor likes to climb, and comfort level with the entanglement possibilities from each method are factors.

The Student
Leaving the aforementioned (in other posts) differences between direct-bag vs. pilot-chute assist aside, remember the biggest factor affecting deployment is you. A solid arch and eye contact with your instructor will go a long way toward better deployments regardless of method.

One possible drawback, from the student's point of view, to pilot-chute assist SL method is transition training. Ask if you will need to transition from ripcord to throw-out at any point in your training. If so, be aware it may cost a small additional fee to transition and may lead to a disconcerting moment the first time you forget you're not on ripcord anymore.

In summary, both IAD and SL are valid training methods. The differences are minor compared to the other differences between dropzones and instructors. A well-run, professional SL dropzone will be superior to a poorly-run IAD dropzone, and vice versa.

I gather you have started training at one DZ, but are considering switching to a different one that uses static line. If you are comfortable with the competence and professionalism of your current instructors and the general atmosphere of your current DZ, stick with IAD. If your current DZ is reminiscent of "Fandango", then by all means explore other options. But don't switch DZs simply on the basis of chest-thumping `SL(IAD) rules IAD(SL) sucks' arguments.

Hope this helps and good luck in your continued training.

Blue Skies,
Johnny

[Andrewwhyte 1]

Quote

>I was overwhelmed by the hideous opening characteristics of the static line sport rigs.

Note that you are talking about the direct bag method of static line. Pilot chute assist gives openings very similar to IAD, since it relies on a pilot chute to extract the main.

Right you are. I have never seen a PC assist system in use so I always forget about it. The only DZ near this guy (Southern Ontario) that uses SL uses D-Bags.

[Trivial_Trekker 0]

Great!
everything makes alot more sense after reading your posts. I was just conserned to which method was safer, and for some reason I thought that static line was abit more of an old school method vs IAD.

Tomorrow weather complying I ll be doing a practice pull ( still IAD ), and soon ill begin going stowed nervous but excited.

BTW, I m able to keep a good arch and keepp stable, but im losing the plane, I think its because I am looking forward to the horizon more than to the side. IS this something i should worry about

[]DETE

[Speed2000 0]

Trivial Trekker,
Glad to help.

As far as losing sight of the plane, don't worry about it, it's normal. Remember, when you let go of the plane, at first, you are moving faster forward than down. As your acceleration downward builds and the energy from the `throw' of the plane bleeds off, your body position becomes less vertical and more horizontal. At this point, assuming a good arch, the plane will disappear from the upper edge of your field of view. This is normal.
As all this is happening, your parachute is deploying behind you. Once it reaches line stretch and begins to inflate, it will lift you back into a vertical (standing) position. At this point, the plane should reappear in your field of view, coming in from the top (but much smaller now).

Students are told to watch the plane, not because we sadistic instructors expect the students to be able to keep continuous sight of the plane, but because it keeps the student's head up, improving the arch. Right now, sitting in front of your computer, you can demonstrate this. Imagine you are letting go of the aircraft. First, put your chin on your chest, like you're looking at the ground. Take note of your body position. Now, tilt your head all the way back, like you would if you were trying to keep eye contact with the plane. In which position did you have a better arch?

Have a great jump (or more than one) tomorrow, and Blue Skies,
Johnny

PS - By the way, the first ten second delay is a money jump. Up until that point, you will have been very busy during your brief excursions into freefall. But, your first ten second delay, you will have a little time to actually pause, look around, and enjoy the view. A person can fit a lot into a handful of seconds. For many, it is a deeply spiritual/existiential experience, and cements their falling in love with the sport. For me, of all my jumps: night, demo, military, record attempts, big ways, CRW, malfunctions, whatever, my first ten second delay remains etched in my mind as one of my most memorable. Drink every moment of it once you get there (but remember to pull ).

[riggerrob 558]

The only DZ near this guy (Southern Ontario) that uses SL uses D-Bags.

[riggerrob 558]

Quote

>I was overwhelmed by the hideous opening characteristics of the static line sport rigs.

Note that you are talking about the direct bag method of static line. Pilot chute assist gives openings very similar to IAD, since it relies on a pilot chute to extract the main.

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

Pilot chute assist (static-line) is the worst system because it (is the longest and) allows the student too much time to back loop through his lines, grab a pilot chute, etc.

Trust me, I have worked with: military static-line, military surplus static-line, pilot chute assist S/L with fore-and-aft gear and round canopies, PC assist S/L with piggy backs and square canopies, direct bag S/L with squares, IAD with Para-Commanders, IAD with squares, etc.
IAD is my favorite method.

[BrianM 1]

Quote

Mind you, the other school requires two weeks of push-ups before they allow you near an airplane and the graduation dive is done wearing a ruck sack, rifle and snowshoes, at night, on a round, from 1000 feet!

There, I fixed it for you.

Needless to say I didn't tell them that I was a skydiving coach, instructor and rigger until after said graduation jump.

"It's amazing what you can learn while you're not talking." - Skydivesg

[pchapman 262]

Quote

I was just conserned to which method was safer, and for some reason I thought that static line was abit more of an old school method vs IAD.

Either method, well done, is safe & effective.

But I'll agree that static line is old school! (I instruct at the Ontario DZ that uses static line but doesn't require 2 weeks of pushups...)

It isn't as popular, it does require more types of gear and more transition training, it is an older technique, and it's not as cool because students aren't getting any real freefall.


Maybe I should leave it at that, but I will comment on a couple things Andrew White mentioned. A lot of what he said is either true in general, or something he has actually seen, but some counterbalancing ideas can be added.

Quote

Our line twist rate was at least five times what it is for IADs out of the same aircraft

True. Off the top I my head, it could be 25 - 50%. But I don't keep track because it doesn't matter much. Yes, students just drift a bit while untwisting.

One hazard might be the occasional student who wants to cut away from line twists despite their training, or who pulls their toggles before untwisting.

As for mals, yes the direction of air flow should make mals more likely. The DZO at the place I jump has a packing method that is supposed to somewhat counteract that. I don't know what the real numbers are, but the DZ has often enough had seasons with zero or one canopy mals when training 500-1000 first timers per year, plus whatever repeats there are. While there's lots of opportunity to debate malfunction rates, I just don't want it thought that direct bag static line automatically means a lot of mals.

Quote

The argument has been made that static line is a more sure way to get 'something' out. To this I call bullshit. The last time I saw a pilot chute in tow on an IAD was over ten years ago.

"Getting something out" is one of the DZO's reasons I believe. When critiquing IAD, I never figured PC in tow was the biggest worry. It was the student tumbling, and grabbing or getting entangled with the PC. That was a significant factor in first jump student deaths in BC in '91, Alberta in '93, and Ontario in '95. The students all had reserve parachutes available so IAD didn't "kill them". (There were plenty of other issues involved.) But IAD is more likely to give a student a nasty high speeed mal than does static line.

There's also the worry about the PC over the tailplane. But that comes down to understanding good ways to do IAD and training instructors appropriately. Just because I know a DZ that twice ripped up the tail of their aircraft due to IAD (in the 80s), doesn't mean other places can't do a lot better!

While static line (direct bag style!) doesn't have that high speed mal issue, it can still suffer from students getting caught up in the lines when backflipping off the step. Or because of the direction the canopy is extracted, a riser can get caught under the reserve pack tray causing a mal. Gear design and packing techniques can minimize this. Still these are valid issues with static line.

[Trivial_Trekker 0]

Hey Pchapman

BTW I did my first tandem at your home DZ when I was 16(3 years ago). It was one of the only places in Ontario that would let me jumpat that age.

anyway it was an awesome first jump.

[]DETE

[billvon 2,435]

>Pilot chute assist (static-line) is the worst system because it (is the
>longest and) allows the student too much time to back loop through his
>lines, grab a pilot chute, etc.

I started on a PC assist system with throwout pilot chute rigs. While I was an SL JM we used both PC assist (with springloaded PC's) and direct bag. Direct bag seems to be the way to go if you want to ensure openings, but the openings are very ugly because the main is essentially opening sideways to the relative wind. I saw sliders forced halfway down the lines before the main was even clear of the bag. PC assist with springloads seemed like the worst of both worlds. Unstable students had more problems with PC assist, but that system also gave the student the best openings during good exits and gave them time to practice DRCP's.

[riggerrob 558]

billvon,
You are correct in saying that one advantage of pilot chute assist static-lines is that they give the student more time to pull their practice handles, however, I put a higher priority on getting a canopy overhead a first-timer.
PC assist S/L just gives clumsy students too much time to grab a half-deployed canopy.

[MissyOutTheBox 0]

Personally I am glad I went the s/l method.. Never really had one problem except one small line twist which just as soon as I looked up and saw it, it was gone.. I have 11 jumps now, of course due to the way I travel for work and crappy weather and a few off-center prcps my 11th jump last weekend was my 5 second delay.

When traveling in the NE from feb-late april I found a small dz in kutztown, PA that offered IAD and ended up heading over there and taking IAD recurrency as the dz allowed me to after showing them my log book and was going to make an IAD jump but the weather went to you know CRAP! Either way I am glad I took the route of s/l over AFF as my canopy control and landings I feel comfortable with. I also like the IAD training route I guess because it is similar to s/l..

Now this is the opinion of someone yet still a newbie but I haven't landed off the dz since the first 2 jumps.. As a matter of fact I am going to try weather permitting this weekend to get jump 12 in which my JM said I will get maybe to almost to altitude..(I am not rushing it, if you are wondering). At least maybe then when I leave for Venezuela on the 29th I maybe able to do a few jumps down there to keep current till I get back..

s/l and IAD Rock! Especially when you have great JM's...

Have always wanted to be a social butterfly but now I have the wind beneath my feet.

[billvon 2,435]

>I put a higher priority on getting a canopy overhead a first-timer.

That is, perhaps, a reason that direct bag is more suitable for someone making a one time jump (or for military jumps) than for people who wish to learn to freefall.