Looking ahead, L1 Cert rocket

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Jon Craig

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Yeah, I'm looking ahead, but I already know I'm going to want to get my L1 certification (at the very least, hehe).

In my initial "Whoa, I'm excited about this, order everything @ once" order, I included what I planned to be my eventual L1 cert rocket, a PML Callisto. I chose that model mainly based on PML's reputation as well as the low cost of the model.

What I wasn't paying attention to is that the Callisto is designed as a super high altitude performer. :D Heh. Probably NOT what I really want for a cert flight. Soooooooo, I'm wondering: do I build the thing purposely to reduce it's potential altitude, or should I just order a different rocket for cert flight? :)
 
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Jon...Welcome to the addictive world of rocketry. ;)

The Callisto will be fine build as is for an L1. However there are several things you can do to help make the flight successful:

1. Use the smallest H motor available which I believe is the AT H128. That will hit about 2800 according to PML's spec page which is waaaay up there for a non-ddeploy rocket but is very do-able with a decent field.

2. Goto a launch and rent a tracker. Talk with your local club members and they will likely know who is willing to do this. Probably overkill for a rocket flight below 3k but it can't hurt. Just this past spring we had a club member fly a single deploy Callisto on a Ellis I164 and landed about 2 miles away but with a tracker and A LOT of walking he was able to find it rather easily.

3. Use a packet of tracking powder.

4. Paint the rocket in fluorescent colors.

5. Try flying it on smaller motors before doing the H and see how it performs. It will probably hit about 2000-2200 on a G64 so the H128 is only going to be another 800 or so feet higher.

-Dave
 
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Jon

The type of HP rocket you launch depends on the fields you have access to. A quick rule of thumb is that for every foot of apogee you attain, you will drift 1 ft sideways during recovery from an apogee deployment in a 10 mph wind. If your apogee is 2800 feet and your field routinely has 10 mph winds, you rocket will land about 2800 feet away from the launch pad, probably not a problem in the midwest, but a big problem in the northeast where open space is at a premium.

At our 240 acre launch site, we strongly recommend that folks use a 4" 3/4FNC rocket for their L1 cert because we require infield recovery for all high power flights. The apogee will not exceed 1500' so the rocket should land within 1500' of the pad on most days.

As Dave said, it's a really good idea to employ a tracker or beeper in any small HP rocket. You're from IN so you're probably launching near a corn field and it's very difficult to find a small rocket in a large cornfield without one.

Bob
 
You're from IN so you're probably launching near a corn field and it's very difficult to find a small rocket in a large cornfield without one.

Bob

Our summertime launch site is actually a semi-gigantic sod farm. It's nice and flat with no large vegetation (i.e., not a cornfield, thankfully).

I'll have to ask the club how big it actually is, as I'm really bad at estimating sizes/distances by sight.

As far as the 3/4FNC 4" rocket, yeah, I was thinking of getting a 4" Goblin and keeping the Callisto for later... Hmm.
 
the four inch goblin is a great kit and you can cut an ebay between the fins for a mini alt. just tape a comm spec tracker to the shock cord with electricel tape and it will stay there all day long. it is a great level two on a j350 but use alum rail buttons as the plastic ones melt. i fly mine on an h all the time.
 
FWIW..I've seen the Callisto used on several L1 cert attempts. While the rocket is smaller than I would (and did) use for a L1 cert, it performs well and the rockets have been recovered WITHOUT the use of trackers on moderately sized fields.

One thing you might try is to downsize the chute slightly, especially if the winds are higher than 10mph. This would reduce your drift. But, you need to do this with a little caution as any structural damage to the rocket will result in a failed cert which could result is too fast a decent with the smaller chute. But the Callisto is a pretty sturdy bird and bringing it down a bit faster using a smaller chute on a soft sodfarm could facilitate easier recovery without too much additional risk in damage. Just another type of decision to make when flying.....
 
it is a great level two on a j350 but use alum rail buttons as the plastic ones melt.

Melt? What the heck are you using for rail buttons?

The standard Delrin and nylon ones both seem to work just fine, flight after flight. There's no reason to expect to have to ever replace them - they will almost certainly outlast your rocket.
 
Our summertime launch site is actually a semi-gigantic sod farm. It's nice and flat with no large vegetation (i.e., not a cornfield, thankfully).

SOD FARMS RULE!!! :headbang:

Flew my L1 at Southern Thunder last month (come to TN next June its an outstanding weekend on the sod) 2 lbs empty to 2100 feet (simmed) on an H242, no electronics, motor ejection, stayed on the field (barely). Repeated that flight last Saturday with an altimeter in the bay to 2177 ft.

As a new HPR guy I would say go with the simplest thing you can, and even more important, spend a day walking around your next club launch and letting folks show you how they do things, that is time well spent.

Good Luck!
 
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I've been flying my 29mm Callisto since 2003. I only flew F & G motors till I certed on a scratch built in 2008 and then threw a H97J in the Callisto. On Monday of LDRS I drag raced my Callisto on a H165R against a friends 3", 6 lb., DD rocket on a EX I400. He had a Pyrodex pellet in the ex motor so he got off the pad first, but the Callisto passed him about half way up. The Callisto only went a couple hundred feet higher then his rocket and his altimeter chirped 2028 ft. It was a pretty calm day, 5 - 8 mph and the Callisto landed about 350 ft from the pad.

My Callisto came with a 24" chute with a 3" spill hole. It comes down plenty fast enough. I usually fly it with a larger chute unless the wind is in the 15mph range. In the six years I've flown it, on upwards of 50 flights, I cracked one fillet and that's been it. I've also never came close to losing it.

I would say: Do your cert on the Callisto and use any of the 29/180 case H motors. If it's a calm day and/or you have a large field, don't be scared of 29/240 load like a H250G. If you have a calm day and a large field you could go for the I200W in the 29/360.

Another piece of advice from flying mine, if you fly on a calm day <8 mph winds, use the longest delay available for any motor you fly. If it's a little more windy, use a medium delay. You can sim the different motors and most will come close with the long delay, but if it's a little breezy and the rocket tilts over early, you'll be better off with the medium delay and a slightly early deployment. This especially important with F & G motors. The Callisto is designed to be stable with the largest 29mm motors so when you fly it on F and G motors, it will be pretty over-stable and weathercock quite a bit. You'll see some of that on the 29/180 motors, but not as bad. For future reference, if it's windy and you're flying it on a F or small G, tilt the pad 5 to 10 degrees with the wind, it will weathercock to a vertical flight.

If you're conservative about your flights, I might not be the best person for advice, I tend to go for the altitude. I didn't cert on my Callisto, I scratch built a DD rocket and used a Loki I110W moonburner to get 4,200 ft. for my L1. I couldn't get that altitude from my Callisto, but it is still calling me to use that I200W.
 
SOD FARMS RULE!!! :headbang:

I gotta agree with you - we (the SLI and USLI folks attending the training with NASA at the Marshall Space Flight Center) flew at that sod field with HARA last weekend - that's one nice field. Of course, my Little Dog decided to take off towards Chatanooga, winding up east of the pads, across the road and into the second field east of the road.... but, at least it was find-able.

Well, except for the nose cone, which is somewhere out there - it's the bright pink one, so if anyone finds it, lemme know, ok? :roll:

Marshall SFC -- SLI Workshop 2009 100.jpg
 
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I gotta agree with you - we (the SLI and USLI folks attending the training with NASA at the Marshall Space Flight Center) flew at that sod field with HARA last weekend - that's one nice field. Of course, my Little Dog decided to take off towards Chatanooga, winding up east of the pads, across the road and into the second field east of the road.... but, at least it was find-able.

Hey it was a lot of fun to have you guys there on Sat. Things got kind of quiet after you'all left. I managed to keep out of the bean fields (barely), this was my only HPR launch of the day. :D

Don't mean to hijack the thread... Jon: Don't know if you're locked into AT motors, but try simming some of the new CTI Pro29s and see what you come up with. Other than that, make it as simple as you can for the cert flight and then start building up the complexity. (That's just my PoV, at the end of the day you gotta do what you gotta do :cool:)

Duster 38mm 069.jpg
 
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I've also seen a number of L1 attempts using a Calisto. Its a tough little bird. Heck I did mine with a Phobos. Still flying after 9 years. Its hard to ding quanrun tube.:D

One thing if you building it stock with the piston. Ditch the black nylon strap from the MMT to the piston. Replace it with 3/8" tubular kevlar. The nylon strap will eventually burn thru.

For most folks I now days recomend a 3" or 4" basic 3FNC type rocket for L1. But the Callisto will work.

Al
 
Jon,
Great choice. The Callisto was my first HPR. Flew it on G-80's at first. I have a 38mm and use a 29mm adapter. Did my L1 on a H128. Landed about 100 feet from the pad. Yeah it's fast and goes high but not out of sight(H128). Haven't put anything bigger in it (yet). It comes down pretty quick but it is hard to find in a soy bean field. I made my own beeper but it wasn't loud enough. It would be a big help if it was louder. One launch I looked for it for 2 hours and gave up. The next day someone turned it into the lost and found table. Very strong rocket, crased it on a parking lot once, no damage. Build it, fly it, you'll love it.
 
Our summertime launch site is actually a semi-gigantic sod farm. It's nice and flat with no large vegetation (i.e., not a cornfield, thankfully).

I'll have to ask the club how big it actually is, as I'm really bad at estimating sizes/distances by sight.

As far as the 3/4FNC 4" rocket, yeah, I was thinking of getting a 4" Goblin and keeping the Callisto for later... Hmm.
You lucky. On a sod farm, ususally the only thing you have to worry about is the irrigation ditches. Your rocket is just fine. If you want some real fun throw in a PRO 38 H400 V-Max motor for the ride of your life.

Bob
 
You lucky. On a sod farm, ususally the only thing you have to worry about is the irrigation ditches. Your rocket is just fine. If you want some real fun throw in a PRO 38 H400 V-Max motor for the ride of your life.

Haha, I bet that would rock indeed. :D

Though, due to conversations with various people, the 38mm case I have on the way is a Rouse-Tech (Aerotech compatible of course).

I might try an I for a cert attempt though... If I fail it, who cares, can just try again...right? :D
 
Jon

Wrong attitude.

Cert on an H. Get your L1. Then use the I.

Bob
 
Yeah... You gotta be CERTIFIED before you start doin' stoopid stuff. :neener:

Bah, launching the Callisto on an I isn't what I'd call stoopid... :D They're on the recommended motor charts even.. :dark:
 
Bah, launching the Callisto on an I isn't what I'd call stoopid... :D They're on the recommended motor charts even.. :dark:

I am right there with ya... just being a smart a$$.... Of course I haven't been brave enough to put an "I" in my level 1 rocket yet so... :p
 
I really don't see anything wrong with certing L1 on an I motor. I did my L2 on an L2375...
 
I see no reason not to use an I for an L1, especially if it's in a kit that has I motors listed as recommended motors. Besides, learning to judge wind and field conditions and what motors to use and which ones not to use is also part of what you learn. If you've flow MPR and have a good grasp of motor, performance, and altitude with those, that will translate to HPR. If a 2,500 foot flight on a MPR in 10mph winds still works on your field for MPR, it will work for HPR too. It's all about judgment. If the conditions are right to fly an I motor, then you shouldn't rule it out just because it's a cert flight. If you don't know the difference, then maybe you should be sticking to F & G motors until you do.
 
Hey Jon, Brian told me you had a thread out here. We'll be able to assist you on your L1 attempt. I'd be happy to let you borrow one of my Beeline trackers. If you don't go for it before November, the other field has MILES of recovery area.

Are you going to make it out next weekend?
 
Yeah, but Chris, you are ........well.....You! :D


True :D

I kind of wish I had done my L1 on an I though. My L1 rocket (a PML AMRAAM 3, flown on an H123W for the cert) absolutely loved the I284W. It went pretty nicely on the Loki I405 too :D
 
True :D

It went pretty nicely on the Loki I405 too :D

Better than my Gizmo did I'll bet! Tim got some great shots of that CATO. Ordered a few and hoping they show up soon.
 
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