L2 rocket suggestion

[Bobbyg334]

Hi

I’m looking at doing my L2 next month and have a 4” Iris. When I’m running this on the sim on a J420 motor it’s predicted altitude is over 3000ft.

This is too high for the field I’m flying without dual deployment and I’ve also been reading the rocket may not stand up to the thrust produced from a J motor.

I’m thinking I’ll retire the Iris and use it for some lower powered motors and get my dual deployment and tracking sorted.

Has anyone got a good suggestion for an L2 rocket and motor combo that’s going to stay around 1500ft?

Thanks in advance.

 

[Hobie1dog]

get ready for 20 different suggestions This question gets asked about once every 3 months so there are plenty of pre-existing threads asking the same question

 

[SmurfTacoSupreme]

LOC Warlock is a good choice if you want to stay simple and low.

 

[Handeman]

I would suggest a kit similar to the Wildman DarkStar 4 Dual Deploy 54mm. It should stay low on baby J motors but still handle any 54mm J, K or small L motor you want to fly it on.

 

[JackC]

Hi

I’m looking at doing my L2 next month and have a 4” Iris. When I’m running this on the sim on a J420 motor it’s predicted altitude is over 3000ft.

This is too high for the field I’m flying without dual deployment and I’ve also been reading the rocket may not stand up to the thrust produced from a J motor.

I’m thinking I’ll retire the Iris and use it for some lower powered motors and get my dual deployment and tracking sorted.

Has anyone got a good suggestion for an L2 rocket and motor combo that’s going to stay around 1500ft?

Thanks in advance.

Take a look at the LoC Precision Warlock. Big, low and slow. Get the 54mm motor tube, adapt it down to a high thrust 38mm J motor, set her up for motor ejection deployment and you’re good. Should go 1,500 to 2,000 feet and you’ll see it during the entire flight. This is a great rocket for small fields.

 

[SmurfTacoSupreme]

AT J435WS DMS is one option for the Warlock — especially if you don’t have J-capable hardware.

 

[tsmith1315]

This is too high for the field I’m flying without dual deployment and I’ve also been reading the rocket may not stand up to the thrust produced from a J motor.

4” LOC kit? That’ll stand up to a J. Be reasonable with the thrust curve.

It’s a moot point in your case, because of the altitude.

But for others who may reading, most 4” cardboard HPR kits are fine for L2 certs.

 

[AndrewGil]

I did my L2 on a Wildman 3" Punisher. I sent it around 4,300' on a J250. Since then I have flown it to 10k on a K550 at LDRS last year.

 

[ThirstyBarbarian]

My Warlock did about 2,000 feet on a CTI J290 for my L2. Mine may have been a bit lighter than some builds. The day of my cert was windy, and I didnt’t want it to drift too far, so I used a Jolly Logic Chute Release set for 500’ (or maybe 700’? I don’t really remember). It worked great. 2,000 feet is pretty comfortable with a Warlock, and it will definitely remain in sight.

But if 2,000’ is too high for your field, and you must keep it under 1,600’, you could opt for a slightly larger LOC Doorknob. Or you could get the Warlock and buy a section of LOC 7.5” tube, coupler, and bulkhead, and make a removable payload section to add some size and weight. You would have to sim it to see if that would keep it low enough.

The main thing that will keep your rocket low is drag, not weight. So look for the fat kits or scratch build a fat rocket. And faster burn motors stay lower than longer burns for the same impulse. The Thrustcurve website can help you pick motors for low flights.

 

[Antares JS]

The main thing that will keep your rocket low is drag, not weight. So look for the fat kits or scratch build a fat rocket. And faster burn motors stay lower than longer burns for the same impulse. The Thrustcurve website can help you pick motors for low flights.

^ This guy be spittin' facts.

-Actual aerospace engineer.

 

[Andrew Brown]

It sounds like you are looking for a low and slow flying rocket for the sole purpose of a certification. Ask yourself what you truly want to fly, not what will get you a number on a card. Otherwise, you may have a number on a card and a rocket you are not exactly excited to fly. A certification is simply a result of a process. Find the process you want first, then the result will come naturally.

 

[DAllen]

It sounds like you are looking for a low and slow flying rocket for the sole purpose of a certification. Ask yourself what you truly want to fly, not what will get you a number on a card. Otherwise, you may have a number on a card and a rocket you are not exactly excited to fly. A certification is simply a result of a process. Find the process you want first, then the result will come naturally.

 

[Rob Campbell]

You can always use a Jolly Logic Chute Release for simplified dual deployment.

 

[cls]

I'm wondering, why L2 if your regular field is so limited on altitude?

 

[Bobbyg334]

LOC Warlock is a good choice if you want to stay simple and low.

Thanks I'll take a look.

 

[Bobbyg334]

I would suggest a kit similar to the Wildman DarkStar 4 Dual Deploy 54mm. It should stay low on baby J motors but still handle any 54mm J, K or small L motor you want to fly it on.

Thank you, that's not one I've come across but will check it out

 

[Bobbyg334]

Take a look at the LoC Precision Warlock. Big, low and slow. Get the 54mm motor tube, adapt it down to a high thrust 38mm J motor, set her up for motor ejection deployment and you’re good. Should go 1,500 to 2,000 feet and you’ll see it during the entire flight. This is a great rocket for small fields.

That's exactly what I'm looking for, I don't want to over complicate the cert flight.

 

[Bobbyg334]

You can always use a Jolly Logic Chute Release for simplified dual deployment.

I'm wondering, why L2 if your regular field is so limited on altitude?

I've got an egg timer altimeter that I've built and tested but want to keep the cert flight simple and leave the dual deployment for further development in a non testing environment

 

[Bobbyg334]

My Warlock did about 2,000 feet on a CTI J290 for my L2. Mine may have been a bit lighter than some builds. The day of my cert was windy, and I didnt’t want it to drift too far, so I used a Jolly Logic Chute Release set for 500’ (or maybe 700’? I don’t really remember). It worked great. 2,000 feet is pretty comfortable with a Warlock, and it will definitely remain in sight.

But if 2,000’ is too high for your field, and you must keep it under 1,600’, you could opt for a slightly larger LOC Doorknob. Or you could get the Warlock and buy a section of LOC 7.5” tube, coupler, and bulkhead, and make a removable payload section to add some size and weight. You would have to sim it to see if that would keep it low enough.

The main thing that will keep your rocket low is drag, not weight. So look for the fat kits or scratch build a fat rocket. And faster burn motors stay lower than longer burns for the same impulse. The Thrustcurve website can help you pick motors for low flights.

I was thinking about a scratch build as I've built a few low power rockets that have flown extremely well and I enjoyed the design process using openrocket. Unfortunately I don't have the facilities here yet so it has to be a kit for now. I'll take. look at your suggestions, many thanks

 

[Titan II]

I'm wondering, why L2 if your regular field is so limited on altitude?

Seriously? Maybe it is because his car is capable of going further than his home field on occasion.

 

[Donnager]

I'd choose any 5.5" LOC product. Goblin, Wolverine, MinieMagg, Iroc....etc. A 7.5" Megamagg, Warlock, or T-Loc would work fine as well.

You can use a 4" but it will go higher, and you may need DD or a chute release to get it back on a small field.

 

[Handeman]

Thank you, that's not one I've come across but will check it out

Look at other similar ones too.

I would recommend that for a general overall L2 rocket on east coast fields, that you look for a 4" diameter, DD, 54mm MMT rocket, that weighs in about 6 - 9 lbs. A baby J will get you 2K - 3K ft. You can use L1 motors for lower altitudes. The commercial 54mm L motors will get you 8K - 10K ft.

 

[ThirstyBarbarian]

I was thinking about a scratch build as I've built a few low power rockets that have flown extremely well and I enjoyed the design process using openrocket. Unfortunately I don't have the facilities here yet so it has to be a kit for now. I'll take. look at your suggestions, many thanks

Scratch builds are challenging for larger than LOC diameter rockets, especially making the nosecones. So a LOC 7.5” diameter kit sounds like a good bet to me, maybe with the optional payload section and chute release I mentioned.

I like my Walock. It’s a fun rocket! And I actually prefer low flights around 1,600‘. I like to see the whole flight, including the parachute deployment. My eyesight is not great, and I don’t like to walk far for recovery. So for me, it really satisfies a lot of priorities. I also enjoy lofting payloads in the rocket, like monkey skydivers or treats on streamers. There’s a lot of room in that thing.

Good luck on your choice and on your cert attempt!

 

[David Schwantz]

Hi Thirsty, what do you do to deploy your stuff? How do you make sure they come out? What about BP burning?

 

[tsmith1315]

Hi Thirsty, what do you do to deploy your stuff? How do you make sure they come out? What about BP burning?

Short shock cord and a loose nose cone?

 

[Ez2cDave]

I'm wondering, why L2 if your regular field is so limited on altitude?

L2 provides access to EX, if he is so-inclined.

Dave F.

 

[ThirstyBarbarian]

Hi Thirsty, what do you do to deploy your stuff? How do you make sure they come out? What about BP burning?

For something large that’s one piece, like the monkey, I like to use 3 flame-proof blankets. I use an old ratty sacrificial one right down near the bottom end of the shock cord where it attaches to the booster to block as many flaming particles as possible and protect the shock cord, and I use a normal chute protector blanket near the chute to protect the chute as normal. Then, I also attach a good-sized flame-proof blanket partway along the shock cord between the chute attachment point and the booster attachment point. That one is for the monkey.

I put the bottom sacrificial chute protector right over the motor tube hole where the ejection charge will blow out, pile a good amount of dog barf over that, z-fold the shock cord and put that in, then wrap the monkey in his blanket and place him on top of the shock cord, then the rest of the cord on top of the monkey, then the chute burrito, and last the leader section of cord to the nosecone. Use a big supplemental ejection charge, and the momentum of the nose cone will yank everything out sequentially in the right order. The monkey gets dragged out in the blanket, and when he clears the body tube, he flies free.

A few other tips. I use very high-thrust, very short-burn motors to keep the altitude as low as possible, so you can actually see the monkey jump out — usually CTI H399 or H295 that go 600 or 700 feet at most. I use a chute release on the monkey so he can fall a ways before deploying his chute. That’s a crowd pleaser!



If I’m doing something like dumping candy, then I use my removable payload section. It’s 15” or so of LOC body tube, a LOC coupler, and LOC bulkhead. Basically just a big bucket. I have an attachment point for shock cords on both sides of the bulkhead, one on the inside and one on the outside. I remove my nosecone from the leader on my normal recovery setup, attach the outside attachment point there, and then attach the nosecone to a new leader that attaches the the inside attachment point. The chute is between the booster and the payload section, so when everything is suspended from the chute, the payload is hanging open side down, and all the goodies just dump out.