rocketsam2016
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- Aug 31, 2016
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Hi folks,
TL;DR: Is 23fps descent too hot for a fiberglass L1 cert at MMMSC (grass) using a chute release? Does answer change given plan to eventually add mounted electronics (i.e. fragility and weight) for more traditional dual deploy? Details below
I'll be attempting my L1 on Oct 1 with MMMSC, launching a madcow 4" fiberglass little john on a CTI I236BS (38mm adapted to 54mm motor tube). An H would've been better, but I was able to get a cert special through Apogee and they were sold out of 38mm CTI Hs I could use (can't use skidmark or vmax).
I have a chute release that I will probably use unless it is dead calm since the rocket sims to around 2k feet on this motor. I have some plans for how to modify the rocket for a true electronic DD setup with a tender descender that I think will probably add about a pound, but I'll only embark on that after the cert flight. I'll start a separate thread with those plans to get feedback.
In my enthusiasm I bought a 36" classic fruity chute when I bought the kit (since I saw that madcow offers the kit with a 36" option) and now I'm worried it's a little small. I haven't added fillets yet, but even so I loaded the rocket up and had to add a bunch of nose weight to get the CG 1.25-1.5 calibers ahead of the CP, so my guess is this thing is going to weigh 6.5 pounds at apogee. The fruity chutes calculator says that'll be 23fps which seems a little hot for a cert flight and needlessly fast with a chute release and/or future electronic dual deploy. On the other hand, it's a fiberglass build so maybe it's OK?
So, the question is - should I just bite the bullet and return the parachute for a bigger one, especially given my plan to add electronics to the rocket down the line? Or is 23+fps with a heavy duty fiberglass build no sweat for MMMSC (which is mostly grass IIUC) even on a cert flight?
Thanks!
Sam
TL;DR: Is 23fps descent too hot for a fiberglass L1 cert at MMMSC (grass) using a chute release? Does answer change given plan to eventually add mounted electronics (i.e. fragility and weight) for more traditional dual deploy? Details below
I'll be attempting my L1 on Oct 1 with MMMSC, launching a madcow 4" fiberglass little john on a CTI I236BS (38mm adapted to 54mm motor tube). An H would've been better, but I was able to get a cert special through Apogee and they were sold out of 38mm CTI Hs I could use (can't use skidmark or vmax).
I have a chute release that I will probably use unless it is dead calm since the rocket sims to around 2k feet on this motor. I have some plans for how to modify the rocket for a true electronic DD setup with a tender descender that I think will probably add about a pound, but I'll only embark on that after the cert flight. I'll start a separate thread with those plans to get feedback.
In my enthusiasm I bought a 36" classic fruity chute when I bought the kit (since I saw that madcow offers the kit with a 36" option) and now I'm worried it's a little small. I haven't added fillets yet, but even so I loaded the rocket up and had to add a bunch of nose weight to get the CG 1.25-1.5 calibers ahead of the CP, so my guess is this thing is going to weigh 6.5 pounds at apogee. The fruity chutes calculator says that'll be 23fps which seems a little hot for a cert flight and needlessly fast with a chute release and/or future electronic dual deploy. On the other hand, it's a fiberglass build so maybe it's OK?
So, the question is - should I just bite the bullet and return the parachute for a bigger one, especially given my plan to add electronics to the rocket down the line? Or is 23+fps with a heavy duty fiberglass build no sweat for MMMSC (which is mostly grass IIUC) even on a cert flight?
Thanks!
Sam