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first off, yes, I am after my base number. to me it will mean something.
that being said,
I live in the middle of PA, and am starting to study/learn more about building jumps.
What is an accepted height you would jump from, 1.PCA, 2. SL, 3. freefall 0-2 second delays?
I am in no rush here, but would like something to occupy my time thinking about/recon options over the winter months, and am looking for food for thought.
If any concerns about me, I can give reference to show I'm not a complete idot.

Hey Homie.
one swims on top of the water. the FF gives me some concern but like 100ft diffy. you are speakin to the wrong person. I am the guy behind the lowest and highest jumps. you should tellme to Fark off.
Or send me a message.
Take care,
Tracy

Can your references not advise you on buildings?

Here is a simplistic answer.

For any given BASE site, you consider the landing area in relation to the exit point and figure out how much altitude it will take under canopy to get to the landing area and have a reasonable margin of safety (in case of opening problems). That is your *minimum* required opening altitude.

Next consider that it takes roughly 70 - 120 ft. for a slider-removed canopy to open on a short delay.

Add the minimum opening altitude and the distance required for your canopy to open and subtract the result from the exit altitude. That is the distance you have available for freefall.

DBs, static lines, and PCAs cut the freefall distance out of the equation.

Since you are asking about minimums, let's assume that there is a huge landing area below the exit point, and you will have an on-heading opening that requires no steering to make the landing area and the opening distance is 120 ft.

Minimums for DB, PCA, and static line are around 150 ft.

My lowest building DB was just under 160 ft. My lowest DB (from an S) was about 125 ft. The 160 ft. jump gave roughly a 5 sec. canopy ride.


For freefall, you need to consider your skills and equipment, but I never liked freefalling from much lower than 350 to 400 ft.

Now, consdier that the real world is not forgiving of simplifying assumptions like I have made above. Those only give very rough estimates.

Ok, so that's the quick and dirty answer. My advice is to throw it out the window and find a mentor who can reliably evaluate sites and reliably evaluate your skills and gear.

Walt

(edited for grammar and clarification--I really should read before posting...)

Walt, you suck as always. I miss you dude and you are spot on with your reply.
take care. space

Thankyou, my friend. You're the man.

Note to the OP: You would do well to contact to base283 and listen to what he has to say. He has quite a bit of expertise on how to do things right and just as important, how to do things *wrong*.

Walt

"What is an accepted height you would jump from, 1.PCA, 2. SL, 3. freefall 0-2 second delays?"


Im sure you know this but asking that question on here is similar to asking: whats the best vented canopy out there, what 2-pin rig should I buy for a first rig, best helmet used for BASE jumping......you'll get all sorts of answers. There are jumpers out there who pretty much live for the dirty low (usually its all they have in their area) so FFing a 200ft. B is "normal". I watched a guy FF 180ft A once, landed and stuffed his canyop away went on like it was just another jump (and to him it was).

So the advice about assessing each object and discussing/listening to your mentor is the best way to go. Take it object-by-object and take it slow.

Good Luck

There are more factors then just height that determine the best method of deployment.

walt im gonna drill this in my head until i half understand it,then brake it down and mither you on how you calculate these equasions,I sense your the man on all things base! john

That is probably the most naive assumption you could possibly make.

Let me be clear about this:

• I am no longer an active BASE jumper.
  
• I am somewhere between a "has been" and a "never was".
  
• I don't know shit compared to many of the jumpers today.

If you run across my name doing internet searches on BASE jumping, it is because a long time ago, before there was much info available on BASE, I documented what I was taught and made it freely available on the internet. I believe I was the first to do that.

At the time there was a real need for information like that because of bunch of jumpers who knew nothing about BASE were going out and reinventing the sport and hurting/killing themselves in the process.

These days there is a lot of knowledge and training available and anyone who tries to circumvent the need for serious preparation and formal training in BASE is setting themselves up to repeat the lessons of the past. As one of the posters in your thread in the Hangout said, some of those lessons are written in blood.

Here is a more rational view of who I am. If you are going to commit something to memory, make it this:

I am some dickhead on the internet that you have never met. You do not know my BASE history or qualifications. You would be a moron to risk your life based on what I say in these forums. At most, the few serious posts I make should be considered as only ONE opinion--not THE opinion.

If you are going to BASE, do it right.

edited to add:
Mr. O'Malley, sir, if you are trolling, I bow to you. You have mad skillz. If you are not trolling, you were born about 20 years too late. You would have fit in quite nicely back in the day. Almost certainly you would have been maimed or killed on a BASE jump, but you would have fit right in.

Walt

 I really like this story:
The following is a question on a physics exam at the University of Copenhagen:

"Describe how to determine the height of a skyscraper with a barometer."
One student replied: "You tie a long piece of string to the neck of the barometer, then lower the barometer from the roof of the skyscraper to the ground. The length of the string plus the length of the barometer will equal the height of the building."
This highly original answer so incensed the examiner that he failed the student who immediately appealed on the grounds that his answer was indisputably correct.

The university appointed an independent arbiter to decide the case.

The arbiter ruled that the answer was indeed correct, but did not display any noticeable knowledge of physics. It was decided to call the student in and allow him six minutes in which to provide a verbal answer which showed at least a minimal familiarity with the basic principles of physics.

For five minutes the student sat in silence, forehead creased in thought. The arbiter reminded him that time was running out, to which the student replied that he had several extremely relevant answers, but couldn't make up his mind which to use.

On being advised to hurry up the student replied: "First, you could take the barometer up to the roof of the skyscraper, drop it over the edge, and measure the time it takes to reach the ground. The height of the building can then be worked out from this formula I have worked out for you on my text paper here."

Then the student added, "But, Sir, I wouldn't recommend it. Bad luck on the barometer."

"Another alternative", offered the student, "is this: If the sun is shining you could measure the height of the barometer,then set it on end and measure the length of its shadow. Then you measure the length of the skyscraper's shadow, and thereafter it is a simple matter of proportional geometry to work out the height of the skyscraper. On the paper is the formula for that as well."

"But, Sir, if you wanted to be highly scientific about it, you could tie a short piece of string to the barometer and swing it like a pendulum, first at ground level and then on the roof of the skyscraper. The height is worked out by the difference in a gravitational formula, which I have determined here this time on a long sheet of paper with a very long and complicated calculation."

"Or, Sir, here's another way, and not a bad one at all. If the skyscraper has an outside emergency staircase, it would be easier to walk up it and mark off the height of the skyscraper in barometer lengths, then add them up."

"But if you merely wanted to be very boring and very orthodox about the answer you seem to seek, of course, you could use the barometer to measure the air pressure on the roof, and on the ground, and then convert the difference in millibars into feet to give the height of the building."

"But since we are constantly being exhorted to exercise independence of mind and apply scientific methods, undoubtedly the best way would be to knock on the janitor's door and say to him 'If you would like a nice new barometer, I will give you this one if you tell me the height of this skyscraper'."

The student was Niels Bohr, the only Dane ever to win the Nobel Prize in physics.
Take care,
space

All of Bohr's answers are invalid because they all use some external objects (string, timer, ruler, reference book for pressure to height conversion, janitor), while he's asked to measure the height using only a barometer.

You know your height. Measure the pressure difference between your feet and head, and bottom and top of the building; the building's height is your height times the proportion of the two pressure differences. Or simply use barometer to make marks of your height on the walls as you go up the stairs.

Nope, too complicated. Just have a young and brave guy freefall it first

Ya know....I've found most most tall buildings are easy to find online if you know the name of them. Search the name of the building and where it is and 9 out of ten times it will pop up with basic history info including completion and height. Try wikipedia. And of course the simple range finder from Wally World works well too.

Well, if you take the time to research online, then with a little effort you'll find complete blueprints, not just heights Really handy in terms of ins and outs...

I usually look up the height of a building on the internet or look it up in the World Almanac.

Neils Bohr's son, Aage Bohr, also won the Nobel Prize in physics. Another Danish Nobel Physics Laureate.

http://www.emporis.com

test out all of your proposed deployment options from a bridge or remote antenna first, gain knowledge and experience by doing so, then apply new found knowledge and experience to your hypothetical B options... evaluate landings, ingress and egress, timing...

Then jump the B.. reply back when you're done, good luck.

currently doing just that. I have a nice remote unquided tower I am enjoying. In no rush for the building, but yes I want it.