dannydan 5 #1 January 30, 2009 ... have some WITNESS accounts of the reserve deploying way under their predetermined altitude height! Does anyone have any questions or possible answers to these scenarios? Does anyone not understand my question or my angle of this querstion? We are informed that an AAD is set to deploy BY a certain altitude IF the speed is FAST enuf to set the computer in motion to carry out the sequence of action RIGHT? So with some of these near the end of the year 2008 deaths and witness accts are saying they see reserve deployments UNDER (lets say) 1000 ftAGL, then what is happening to cause these low ADD fires? Is it because the decent rate of the jumper has slowed down and gains speed again but after the jumper is too low.... forgive me of my ignorance... peace be safe and forever BLUESKIES! dd Quote Share this post Link to post Share on other sites
labrys 0 #2 January 31, 2009 QuoteSo with some of these near the end of the year 2008 deaths and witness accts are saying they see reserve deployments UNDER (lets say) 1000 ftAGL, then what is happening to cause these low ADD fires? An AAD doesn't deploy a reserve, it cuts a closing loop. After the closing loop is cut, the rest of the reserve deployment sequence has to go right and sometimes it doesn't. As for your question about low openings: A "perfect" AAD fire and reserve deployment is normally under 1000 feet so I guess I don't understand your question well.Owned by Remi #? Quote Share this post Link to post Share on other sites
humanflite 0 #3 January 31, 2009 Quote... have some WITNESS accounts of the reserve deploying way under their predetermined altitude height! Does anyone have any questions or possible answers to these scenarios? Does anyone not understand my question or my angle of this querstion? We are informed that an AAD is set to deploy BY a certain altitude IF the speed is FAST enuf to set the computer in motion to carry out the sequence of action RIGHT? So with some of these near the end of the year 2008 deaths and witness accts are saying they see reserve deployments UNDER (lets say) 1000 ftAGL, then what is happening to cause these low ADD fires? Is it because the decent rate of the jumper has slowed down and gains speed again but after the jumper is too low.... forgive me of my ignorance... peace be safe and forever BLUESKIES! dd As Labrys says, it sounds like you are talking about AAD fires here.... Have a read of this very informative Cypres document.(well, I thought it was useful anyway!) It explains a huge amount about how the Cypres operates and clears some myths up about its operation. http://www.cypres-usa.com/cyp13.htm If the Cypres cut the closing loop at the right altitude - around 850 ft iirc (ish) then it did its work. Problematic or slow reserve opening is nothing to do with Cypres... but at those altitudes it can clearly mean the end game.. Quote Share this post Link to post Share on other sites
dannydan 5 #4 January 31, 2009 Problematic or slow reserve opening is nothing to do with Cypres... but at those altitudes it can clearly mean the end game.. This I understand, human.. and I also understand that the AAD doesnt actually "deploy" the reserve..(my bad/wrong wording) Thanks for the link I shall go read uP! If what i heard over the years but mainly in my first year, i was either told because I asked or just overheard a conversation about low altitude (under1200-1500AGL) and or speed of 85mph +/- a cple of mph was what started the sequence for the AAD.. Meaning that if a jumper was not in control at (lets say 1500AGL) and was traveling down at 85mph or more then at least those two reasons was all the computer (AAD) needed to "fire" or cut the reserve closing to start the reserve deployment seq!? Im going to go read now! I also need to do a search to see what my AAD is factory set at if there is a standard setting that the manuf use. I purposely have not mentioned any one particular manuf in my op as well as this! They ALL have basically the same purpose, so therefore I didnt feel the need. One time i removed myself from a load at the WFFC because I remembered after boarding a CASA that I didnt turn it on. It was my experience in life and lack of experience as a jumper that caused that reaction! I am still ok with that decision today.. brb Quote Share this post Link to post Share on other sites
airtwardo 7 #5 January 31, 2009 It was my experience in life and lack of experience as a jumper that caused that reaction! I am still ok with that decision today.. I take it from your post that you're alive...so it's hard to argue with success! ~ If you choke a Smurf, what color does it turn? ~ Quote Share this post Link to post Share on other sites
PhreeZone 20 #6 January 31, 2009 The height for a AAD fire by the major players is under 1000 feet. Cypres is at 750ft (estimate based on pressure) and the others are right at or jsut slightly higher, all are under 1000 feet.Yesterday is history And tomorrow is a mystery Parachutemanuals.com Quote Share this post Link to post Share on other sites
tombuch 0 #7 January 31, 2009 One of the other variables is the placement of the AAD. Activation is dependent on air pressure, and the air pressure around our body will vary in freefall. Thus, the AAD may sense deployment altitude higher or lower based on where the unit is located on the jumpers body, and the position the jumper is in as he moves through the air. An AAD is never 100% reliable, and shouldn't be thought of as such.Tom Buchanan Instructor Emeritus Comm Pilot MSEL,G Author: JUMP! Skydiving Made Fun and Easy Quote Share this post Link to post Share on other sites
DARK 0 #8 January 31, 2009 QuoteThe height for a AAD fire by the major players is under 1000 feet. Cypres is at 750ft (estimate based on pressure) and the others are right at or jsut slightly higher, all are under 1000 feet. is a student cypres not set up for 1500ft? maybe thats where he is getting confused. Quote Share this post Link to post Share on other sites
labrys 0 #9 January 31, 2009 IIRC, a student Cypres will activate at either 750 or 1000 feet depending on rate of descent. Edit: Found what I was thinking of on SSKs website: QuoteSpecifically designed for student requirements. It will activate when the rate of descent exceeds 29mph (13m/sec). The activation altitude, however, is split. In the case of rate of descent being equal to that of freefall, the opening altitude is at approx. 750ft, as with Expert Cypres. However, should the rate of descent be lower than that of freefall but still above the limit of 29mph (e.g. with partially opened canopy), then Student Cypres activates when the altitude decreases below 1000 ft AGL.Owned by Remi #? Quote Share this post Link to post Share on other sites