[Milsurplus] BC 611 chute jump

[Mark]

Ray Fantini wrote:

"Reminds me of the old stories about the URC-4 survival radios and how if you had the radio and battery strapped to you on a bail out as soon as your shoot opened the jerk of the shoot was enough to cause the heavy URC-4 to rip thru your flight suite and quickly disappear."

Opening shocks can vary wildly. Normally they aren't bad at all. Sport gear has devices to slow the deployment of the main chute to lessen the G forces. Sometimes it doesn't work right and you go from terminal velocity to near zero in about a second. Terminal velocity varies from about 120 mph (horizontal) to over 300 mph (vertical) depending on body attitude. These abrupt deployments are called SLAMMER openings and for very good reason. 

I had one opening so brutal that  it broke a number of new suspension lines and busted so many blood vessels in my face that it looked like I had been beaten up. I was seeing stars for several seconds after it happened. My main chute was rendered uncontrollable and I had to do a cutaway and deploy my reserve canopy. This took place over Chanute AFB in Rantoul Illinois during a huge skydiving meet in 2005. 

Severe opening shocks have actually killed a few skydivers. What happens usually is a dissection of the aorta. It literally is ripped off the heart by G forces and the jumper bleeds out on the way down. It's rare but it does happen periodically no matter how many technical advances are made to prevent it. A parachute opening is a very chaotic event and not entirely predictable or controllable. 

We try to be as safe as possible on our radio jumps and open long before we reach terminal velocity. On my BC 611 jump last weekend I popped my main chute after only a few seconds of freefall. An abrupt opening at that speed wouldn't pull very many Gs. 

By the way, modern sport parachute gear no longer uses rip cords to deploy the main chute. A folded pilot chute is stowed in a Spandex pouch at the bottom of the canopy pack carried on your back. You can't even see it. You have to feel for a toggle handle tied to the apex of the stowed pilot chute, grab it, pull the pilot chute out of the elastic pouch and release it into the vertical slipstream. The pilot chute inflates and pulls the opening pin. It sounds kludgey but it works really well. 

I know there are a number of old skydivers who are also hams. I'd especially enjoy hearing from any who hang out here on the mil surplus group. 

Any suggestions on how to get some good 75M AM parachute mobile QSOs with the BC 611 would be much appreciated. All I can think of is using a long trailing wire antenna properly loaded. Radiated power is just too low using the OE telescoping whip. 

73
Mark
AF6IM
www.parachutemobile.com