I was just asked if Paragliding Tales and Reviews (
http://www.paragliding-tales-and-review ... ident.html ) is a reliable source for accident information. The guy says:
"Here are some figures from a 15-year period from 1991 to 2005 inclusive. There were 53 known paragliding fatalities, but 1991 to 1993 were rather risky years to fly."
He's using fatality numbers for members of the USHPA who were killed on paragliders in the United States. Outlaws are not included, nor are fatalities of USHPA members like Scotty Marion (2003) who died in other countries. I have found several people who succumbed to their injuries months or years later but never made the USHPA list. The crucial names, dates and place of accident were not provided by PG accident chairmen Paul Klemond, Jim Little or Mike Steed - so how can anyone validate their opinion, data or research? Only Doug Hildreth was man enough to regard the membership of the USHGA as capable of thinking for themselves - but he left us before paragliding reared its ugly head and made the U$HPA your nanny.
I have documented 412 global PG fatalities and 159 global HG fatalities during the period of 1991 to 2005 inclusive. These are underestimates. Total global HG and PG fatalities appear to have reached parity somewhere in 2006.
Since the beginning of 2006, at least 808 additional soaring parachutists have died, along with at least 96 HG pilots.
The haphazard data collection common among freeflight organizations conceals the truth about paragliding: Parachutes are really dangerous. They collapse and kill their falling humans. They have a Dead Man's Curve all their own.
Because of their slow flying speeds, paragliders tend to enter the PDMC (Paraglider Dead Man's Curve) with very little forward motion. However, Paragliders can enter the PDMC with a wide range of vertical velocity. The fact that this boundary is not flat may play a role in the observed delay of deployment by pilots entering the PDMC at high rates of descent. These pilots may be incorrectly basing their minimum reserve deployment altitude on the PDMC boundary that applies to paragliders experiencing full collapse at the boundary - which is a very different case.
Paragliders experiencing an emergency within the PDMC are likely to experience serious injury or death. In the chart above, the PDMC upper boundary is established using 4 seconds for the pilot to react, grab, throw and, hopefully, experience a successful deployment. While some pilots claim they can successfully deploy in as little as 2 seconds, observations of pilots in emergency situations indicate deployment times often far in excess of 4 seconds, indicating the PDMC boundary is set too low.
1: Collapse Near the PDMC
The left column represents a paraglider experiencing an emergency while entering the PDMC boundary. Beginning essentially from rest, the paraglider undergoes full collapse and descends at the acceleration of gravity. Note that the speed required for the reserve to snap open is reached only in the final seconds. The pilot will invariably impact before achieving terminal velocity.
2: High-speed Descent into the PDMC During a Nose-down Spiral Dive
The center column represents a paraglider in a nose-down spiral dive. A paraglider in a nose-down spiral dive does not reach terminal velocity. Although, without deployment, the pilot will impact the ground about 10 mph slower vertical speed than would a pilot experiencing a collapse near the PDMC Boundary, his distance travelled in 4 seconds is slightly farther and therefore he must deploy his reserve parachute at a slightly higher altitude to survive. Compounding the issue is a lateral speed vector that can exceed the vertical vector at impact. Centripetal acceleration can make the deployment attempt take longer or become impossible due to g-forces on the pilot.
3: Terminal Velocity Entry into the PDMC Under Full Collapse
A pilot experiencing a full collapse emergency at altitude is falling so fast vertically that he travels much farther during the final 4 seconds before impact. If he is delaying a reserve deployment in an effort to recover his paraglider, he must be aware that his deployment altitude is much higher; almost double that of a collapse at the PDMC boundary. A mitigating factor that is not accounted for in this chart is the fact that a reserve parachute, successfully deployed, will snap open faster at high rates of speed. This may lower the upper range of the PDMC slightly for nose-down spiral dives and collapse at terminal velocity.
Because of their structural integrity and inherent ability to exchange flight momentum for maneuverability, fixed-wing aircraft do not have a DMC. Note the difference between the PDMC and a typical Dead Man's Curve for helicopters. While a helicopter enters its DMC only by the pilot's option, the paraglider must enter the PDMC at least twice during each flight. This exposure represents risk that is additional to the baseline risk inherent in all types of aviation. Also, in terms of statistical probability, PDMC risk is accumulative over the flying career of a paraglider pilot. This suggests that paraglider pilots accumulate risk at a much faster rate than pilots of other types of aircraft.
by Bill Cummings » Thu Oct 02, 2014 11:46 am 
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