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illusioneer

opening altitude

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Am I remembering wrong? Didn't the "free fall time" charts in the old log books have an opening altitude at 2,000 ft... Now the opening is at 3,000ft. Do any of you old timers know If I am right or did I smoke out too many brain cells in my youth?



You may very well have burned your brain cells, and I congratulate your effort.

My original logbook from 1979 had a freefall chart that assumed an opening at 2,500 feet, The lowest exit altitude listed was 2,800 feet for a static line.

I have a page from the 1972 USPA SIM (it was called something else back then) marked as "Part 150.7" with multiple freefall charts. The key chart is calculated for an opening at 2,500 feet, but includes a note that a jumper should add 2 seconds for an opening at 2,000 feet. It also notes that 2,000 feet is the altitude for openings by C and D license holders, and the FAI accuracy altitude is 1830 feet.
Tom Buchanan
Instructor Emeritus
Comm Pilot MSEL,G
Author: JUMP! Skydiving Made Fun and Easy

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Here is page 1 of USPA Part 150.7, dated July 1, 1972, showing freefall tables for openings at 2,500 feet, and a note for adjustments to 2,000 feet. Keep in mind that these tables were created for old gear, and predate piggyback systems.
Tom Buchanan
Instructor Emeritus
Comm Pilot MSEL,G
Author: JUMP! Skydiving Made Fun and Easy

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Hi Tom,

Also, the first piggybacks came out in Spring '64.



As I recall, piggybacks didn't really fill the landscape until the mid to late 70's, and gear was still very heavy. Plus, at that point we were into the wing wars. Suits and gear didn't stabilize into the 'sleek' rigs and somewhat fitted jumpsuits (Standardized Fall Rate by Flitesuit) until the early to mid 80's, and I think that's when freefall charts were reconfigured for the new gear and techniques. Of course back then 'C' and 'D' licensed jumpers often opened at 2,000 feet, and low pull contests were not at all uncommon.

My first jump was in 1979 in at Frontier Skydivers Wilson, New York. It was on a T-10 with a belly mount round reserve of some kind. I think most of the hot jumpers were still on PC's.

I only made three jumps in 1979 and one jump in 1980. I really hit the sport hard in 1981, and at that point students were still taught on t-10's, but the DZ I was at (Gift of Wings in Java, New York) was super progressive and put freefall students on PC's. They also required a student to pack his own main for that first freefall, so on that jump you had your first freefall, first own pack job, and first PC jump...lot's a fear and lots of beer. After about 30 jumps they had a piggyback square available for the advanced students, but still with a belly mount reserve. The main was a ParaPlane Cloud, also known as the "death square" because it opened so damn hard.

Finally, late in the summer of 1981 I used $700 of student loan money to buy a piggyback rig with a square. It was a GQ Security Unit in a Security System, with a tri-con round reserve. It was pretty cutting edge stuff, but the girl who sold it to me had made about 10 jumps with two malfunctions, so the technology wasn't really on mark yet. I had a couple of malfunctions early on with that main, but once we moved the control line attachment points, gutted the heck out of the slider, and waxed the cascade knots it became a terrific main, and even did time on the BASE circuit starting in 1983.
Tom Buchanan
Instructor Emeritus
Comm Pilot MSEL,G
Author: JUMP! Skydiving Made Fun and Easy

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