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Rocsim or Spacecad Flight data needed for Loc "Warlock"

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Nite Builder

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My wife just recently finished building a Loc-"Warlock" and she will be attempting an L1 cert. flight on Dec.27th. She not only constructed this rocket for L1, but L2 also. Not only did she modify it from 38mm to 54mm, she also fiberglassed it, and then built in her avioncs bay. All good ideas, however with these modifications came additional weight. The total approximate weight fully packed and loaded will be 14-16 Lbs. She will be launching it on an Aerotech I366T. Could someone be so kind to do either a Rocsim or Spacecad fight simulation at the 3 specified weights of 14,15,16 lbs. Nothing else has changed on the rockets outside dimensions except the fin thickness which was increased to 1/4"(was 3/16") Birch plywood. CP & CG were maintained per instructions.( Actually we got an average between Rocsim CP & CG and Loc's CP,CG). She is really concerned about her delay time and when the rocket will apogee. We will be using Aerotech RDK+ delays and were thinking probably a medium delay(RDK-11)I think thats 6-7 second delay. But then I think anyone with a Rocsim could tell me better, or if I'm even in the ballpark for that matter.

I must admit, I am quite proud of her fabrication skills and that she went that extra mile making this an L2 rocket at the same time. So much I thought I would do this post for her. Hopefully we can get an idea on how high it will fly and how many seconds to apogee through flight simulation. Can ya'll help her out?


Thank you~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~>>>====> Fly High..........
Chris Emich
 

LMazza

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The weight that you are talking about is quite a lot for even a large I motor. I didn't have that specific motor (BTW i think its a redline) in rocksim so I couldn't sim that exact configuration.

Delays are: short = ~6 seconds, medium = 10 seconds, long = 14 seconds. It seems you would definitely need the shortest delay in this case. For reference an I435T calls for ~6 seconds under ideal conditions.

Good luck with this. Hopefully another board member will have that specific motor for Rocksim and can help you further.
 

Nite Builder

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Luke:
You are correct and I apologize for not indicating that it was in fact "Redline". With that being said, I now see why a sim on this (Heavy) rocket with the use of an I366R will be a bit more difficult than anticipated. I am also 99% sure that she will need a short delay.

The question that seems to plague us both the most is," How many seconds does each number represent with RDK-Plus delays? (i.e. RDK+11.) What, "in seconds" does the 11 represent. The reason I ask this is because there are so many RDK-Plus delay grains, with numbers ranging from RDK+11 TO RDK+20, and several numbers in between. Not just 3 numbers representing: short,medium, long. I have seen RDK-Plus 11,12,13,15,18 and 20 How many different RDK+ numbers there are, I am not sure. Can't seem to find any info on Aerotech website that displays an RDK delay listing. I think its fair to say RDK+11 is 6 seconds if its the shortest delay but what about the rest of the numbers?

I guess this is gonna be a common sense call....If RDK numbers are ranging from 11( which is the lowest number I have seen, unless someone knows of a lower one?) to 20, I guess its fair to say we will go with the RDK+11. I probably wouldn't be so critical about this if this rocket didn't weigh so much, guess thats why I'm chasin down all the avenues to make sure that the RDK+11 is in fact the shortest delay...Will also still try to get a Rocsim if time permits, just to make sure that even 6 seconds is short enough for that matter! :)
 

als57

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Originally posted by Nite Builder
The question that seems to plague us both the most is," How many seconds does each number represent with RDK-Plus delays? (i.e. RDK+11.) What, "in seconds" does the 11 represent.

I think its fair to say RDK+11 is 6 seconds if its the shortest delay but what about the rest of the numbers?

Nite Builder:

The numbers on the RDK+ delays are not seconds. At least I have never heard anyone make that claim.

I believe you will find on the Aerotech site a chart for the delays for each specific motor. The RDK's are matched to the burn rate of a specific propellant. So a short delay for a WL motor will not be the same as a Redline. Seen some nice shreds result from use of the wrong delay.

For 38mm motors a short delay is 6 sec. A medium is 10 sec. And a long is 14 sec. Go with the recomended delay on the AT site or on the reload bag card.

Wish your wife good luck on the cert flight. I used a stock ( mostly ) Warloc for my L2.


Al:)
 

artu

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How much less would the rocket wieght without the payload/avionics bay ?

I take it is now longer then a stock warlock for the L2 setup.

I'd make the L1 a single deploy, without the payload bays.

I RockSim7ed a 10 pound standard length warlock on that I366R and it needs the short delay 6 secs and fly to 1100 feet.

Perfect for an L1

at 16lbs and with payload/avionics bay it will need a 4 second delay on that motor and fly only to 500 feet. this sounds like possibilities for a lawn dart.

Make sure your motor dealer can confirm for you the right SHORT RDK kit for that motor. the RDK11 says almost 9 secs and this chart says you need an RDK9

http://www.rocstock.org/wizards/rms-delays_2938.pdf
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Rocketman248

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I'd be a little worried about the slow liftoff. If it takes off too slowly, it might arc over and probably lawn dart. To give yourself a bigger safety margin, i'd go with an I435T. Rocksim shows 780 feet with that motor. It has good acceleration as well. You would need RDK+ 09 for the short delay.

Countdown Hobbies has them in stock. I'd give them a call.
 

Stymye

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sounds possible but kinda heavy setup for a L1 cert flight.

no doubt,,,Great for a L2 bird,
but than again the challenge is part of it ..!!
 

DPatell

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An I366R will have no trouble lifting the Warlock. Getting a short enough delay is an issue. You can look at Rocksim and stuff, which I normally do, but I can almost guarantee that the I366 will get it off the pad. I think I would enjoy the flight, too, nice and chippy to about 500'.

That being said, take out the electronics bay and payload section, check stability, and fly it stock length on the I. Much easier, and it will fly to a low enough altitude that Dual Deploy isn't nescessary. Then replace the bays and go for an L2. K.I.S.S.!

Good luck on the L1:)
 

Nite Builder

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Dan:
I completely agree that the I366R will get this rocket off the pad and I also agree that a short delay is necessary. Unfortunately, this rocket has 8 centering rings to support a 26" MMT ( future L2000 motor going in), 3 chamber dividing walls( epoxied in) for 3 seperate avionics bays. It was also "glassed" with a Kevlar sock, and fin thickness was increased from 3/16" to 1/4"( Birch plywood) as well as tang distance being widened to 2 11/32" to meet the MMT. So, needless to say, "removal" of any of these components is not an option. The total weight of this rocket packed and loaded will be 14 lbs 8 ozs. and theres nothing we can do to change that. Good idea though! :) So as it stands, the "Warlock" will go up on Dec.27th on an I366R w/ RDK+9 delay.( 6 seconds). Nosecone and BT have there own respective chutes (just in case of early ejection) and 3000 Lb. Kevlar shockcord.

Thanks to all who have helped in Rocsiming and just plain good advice for that matter. I have much more confidence in the flight of this rocket and God knows my wife does also.
Yeah, I know, I'm one of those lucky guys who's wife doesn't nag them for there rocket endeavors. Instead she says things like,"Hey knucklehead, when ya gonna help me finish my fins"? :) :)

Thanks all~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~:: >>>>====> Fly High
 

artu

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I resimed the loc with stock lengths and your wieght before engine.

725 feet with 5.67 delay.

looks good.

Engine selection
[I366R-6 ]

Simulation control parameters
Resolution: 800 samples / second.
Simulation method: Explicit Euler.
Simulation execution time: 0.645 Sec.

Launch conditions
Altitude: 640.000 Ft.
Relative humidity: 5.000 %
Temperature: 72.000 Deg. F
Pressure: 29.921 In. Hg.
Wind speed model: Slightly breezy (8-14 MPH)
Wind turbulence: Constant speed
Wind starts at altitude: 0.000 Ft.
Launch guide angle: 0.000 Degrees from vertical
Latitude: 90.000 Degrees

Launch guide data:
Launch guide length: 36.000 In.
Velocity at launch guide departure: 33.499 ft / s
The launch guide was cleared at : 0.208 Seconds
User specified minimum velocity for stable flight: 43.999 ft / s
Minimum velocity for stable flight reached at: 62.485 In.

Max data values:
Maximum acceleration: Vert: 191.158 Ft./s/s , Horz: 0.837 Ft./s/s , Magnitude: 191.158 Ft./s/s
Maximum velocity: Vert: 199.382 ft / s , Horz: 11.733 ft / s , Magnitude: 200.718 ft / s
Maximum range from launch site: 295.594 Ft.
Maximum altitude: 725.511 Ft.

Engine ejection charge data:

Conditions at engine ejection charge:
Using a delay time of : 6.000 Seconds
Velocity: 23.030 ft / s
Altitude: 724.009 Ft.

Recovery system data
P: Parachute Deployed at : 7.536 Seconds
Velocity at deployment: 23.030 ft / s
Altitude at deployment: 724.009 Ft.
Range at deployment: -128.507 Ft.


Time data
Time to burnout: 1.536 Sec.
Time to apogee: 7.232 Sec.
Optimal ejection delay: 5.696 Sec.

Landing data
Successful landing
Time to landing: 25.609 Sec.
Range at landing: 295.594
Velocity at landing: Vert: -41.277 ft / s , Horz: 11.733 ft / s , Magnitude: 42.912 ft / s

Competition settings
Competition conditions are not in use for this simulation.
 

Nite Builder

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Wow!!!.....Art, we Thank You. Wasn't expecting that....totally awesome data. Although we can sure "Build" darn good rockets, we are still beginners when it comes to Rocsim software and its uses thereof. We will "definitely" be purchasing Rocsim 7.0 software(or even just download it) after we recover from the holidays. :-0
Most importantly, you have helped to "verify" our choices of delay(RDK+9). Not to mention a "plethera" of data that neither of us ever even knew existed.......It truly is the,"Not knowing for sure" part that effects us rocketeers the most. I personally don't think that a rocketeer should ever be asking themselves the question," I wonder how it will do?" when there walking up to the RSO table, especially when certifying. LOL... :)
Thanks again from the both uf us...and welcome to the forum!

Happy Holidays
 
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