Help Support The Rocketry Forum:

DeltaFuturistics

Active Member
Just wondering what drogue and main would be best for this big boy. Also wondering about cord thickness and length. Plans for this rocket is to have a couple more sensors on it to collect data such as water content in air or temperature using a pi or arduino. Possible gopro or some sort of camera. Build thread hopefully coming soon.

AlfaBrewer

Well-Known Member
I've used the sizes suggested by John on a similar weight rocket with the fins extended below the body with no ill effects. My recoveries were on grass/dirt.

TMJ

"Where the heck'd it go!"
What John and AlfaBrewer suggest, however. You'll need to take note of the 'expected' winds where you will be launching. Ground level, as well as upper level where the drogue will be deployed. I say this due to a recent experience I just had in Argonia, Kansas. I launched an 8.5lb rocket with a 15" drogue and a 30" Recon main. It went up to about 2,200 feet. The ground winds were about 16mph. Not sure of the upper level winds. That rocket came down and was recovered within 300 yards of the pad. I 'then' prepped a 10lb rocket that went up to about 4,800 feet. The winds picked up to about 19mph by launch time. Not sure about the upper level winds on this one, either. I had a 18" drogue on this one, and intended to use a 60" main. Due to the higher winds, I pulled the 30" Recon out of my 7lb rocket and put it into the 10lb bird. The main worked just fine and brought it down slow, albeit. the 18" drogue got caught up in high winds aloft (maybe some thermal activity too). Darned thing wouldn't come down, on the 18" drogue, till it drifted halfway to Nebraska! Once the upper level winds, etc. let go of my drogue, and the rocket FINALLY started to come down... everything went fine and the rocket quickly came down on the main, as hoped in good order.
I know this info is a bit vague, and probably not much help, specifically. Take it for what it is. The hardness of the ground is a major consideration in main chute size, but watch that drogue in high upper level winds, especially if its all brown dirt below. "'Thermal' activity might make for a long flight/drift even with a small drogue."

DeltaFuturistics

Active Member
Wow, it has been awhile since I've been lurking on the forums. We just got the Adventurer 3 in and it's definitely big. It's quite a big jump from a 3ft. 39mm to an 8ft 3in. rocket for L1 and L2 but why not. The only remaining items needed for the kit are tracking/deployment devices, shock cords, and the Altimeter Bays. The rocket will be powered with a 54/2560, not sure on load yet.

Proposed Tracking:
Eggfinder w/ LCD
Altus Metrum: Telemetrum V2
--or--
Instead of two GPS go and invest in an RF system and run one of each(would be tandem w/ Telemetrum)
Thoughts?

Altimeter bay will be from Mad Cow and for the Nose Cone, I was very pleased with Chris Attebery's 39mm nose cone Alt. Bay and will be getting the 3in. version

I'm highly debating on running a Y-harness for the motor tube to shock cord attachment instead of directly adhering the shock cord to the inner motor tube. Thoughts?

The plan is to double cert at the MC2 launch in the end of June.

This is somewhat random but has anyone ever had experience with "wrapping" a rocket with the same material as they do with cars...the removable vinyl stuff. If you have, how well does it hold up and is it easy to apply?

markkoelsch

Well-Known Member
I would go with a Gps and a radio RDF solution in tandem if you can swing the cost.

Anecdotally, I have seen and read of a lot of gps solutions losing lock etc. I have seen very few people have issues with RDF...Black Rock excluded.

I only lost one rocket with RDF. It was a rather aggressive flight, and I am pretty sure that the mount I had my walston transmitter in broke. It was under boost and I heard a weird screech and nothing. Never found that rocket, but I know it was together at apogee and deployed. I later had access to Rocksim Pro, and entered the wind data and I am sure it ended up in a lake.

NateLowrie

Well-Known Member
Wow, it has been awhile since I've been lurking on the forums. We just got the Adventurer 3 in and it's definitely big. It's quite a big jump from a 3ft. 39mm to an 8ft 3in. rocket for L1 and L2 but why not. The only remaining items needed for the kit are tracking/deployment devices, shock cords, and the Altimeter Bays. The rocket will be powered with a 54/2560, not sure on load yet.

Proposed Tracking:
Eggfinder w/ LCD
Altus Metrum: Telemetrum V2
--or--
Instead of two GPS go and invest in an RF system and run one of each(would be tandem w/ Telemetrum)
Thoughts?

Altimeter bay will be from Mad Cow and for the Nose Cone, I was very pleased with Chris Attebery's 39mm nose cone Alt. Bay and will be getting the 3in. version

I'm highly debating on running a Y-harness for the motor tube to shock cord attachment instead of directly adhering the shock cord to the inner motor tube. Thoughts?

The plan is to double cert at the MC2 launch in the end of June.

This is somewhat random but has anyone ever had experience with "wrapping" a rocket with the same material as they do with cars...the removable vinyl stuff. If you have, how well does it hold up and is it easy to apply?
The TeleMini does RDF on the 70cm band. You will need a Ham license for it, but it will work well as a secondary unit. Put that in with the eggfinder on the 900MHz band and you have some good redundancy.

Nick@JET

Well-Known Member
I've only been at this for 4 years, but abandoned the idea of RDF tracker as the proliferation of GPS is strong I would just go that route. However now after using GPS (which I like) and also building some smaller rockets that I want to push , I now need an RF tracker - easy just tape to a shock cord. Might as well invest in one and run it as a back up.

DavidMcCann

Well-Known Member
Curious on your question of a y harness, I typically epoxy both ends of a Kevlar strap to the outside of the mmt. What do you have in mind? (3" with a 54 is too tight for an eye bolt attachment)

DeltaFuturistics

Active Member
I would go with a Gps and a radio RDF solution in tandem if you can swing the cost.

Anecdotally, I have seen and read of a lot of gps solutions losing lock etc. I have seen very few people have issues with RDF...Black Rock excluded.

I only lost one rocket with RDF. It was a rather aggressive flight, and I am pretty sure that the mount I had my walston transmitter in broke. It was under boost and I heard a weird screech and nothing. Never found that rocket, but I know it was together at apogee and deployed. I later had access to Rocksim Pro, and entered the wind data and I am sure it ended up in a lake.
Do you have any cost effective RDF systems in mind? I'm going to start researching RDF on the forums.

The TeleMini does RDF on the 70cm band. You will need a Ham license for it, but it will work well as a secondary unit. Put that in with the eggfinder on the 900MHz band and you have some good redundancy.
That actually sounds like a good idea. Would you think of using the TeleMini as a back-up for D-D and then using a Missle Works RRC3 as the main for D-D?

I've only been at this for 4 years, but abandoned the idea of RDF tracker as the proliferation of GPS is strong I would just go that route. However now after using GPS (which I like) and also building some smaller rockets that I want to push , I now need an RF tracker - easy just tape to a shock cord. Might as well invest in one and run it as a back up.
It sounds like I will have to get one eventually if we want to go higher.

Curious on your question of a y harness, I typically epoxy both ends of a Kevlar strap to the outside of the mmt. What do you have in mind? (3" with a 54 is too tight for an eye bolt attachment)
I guess I should have elaborated more on the Y-harness idea. It's not a traditional Y as like you said, there is no room for Eye bolts. Traditionally, like I did with the 38mm Tomach, you would just mount the cord to one side of the mmt, running it under a slot in the forward CR. I was thinking about using the same width of kevlar cord and simply attaching a length to opposite sides of the mmt and under cut-out slots in the forward CR. Then using a quick-link to attach the shock cord to the length mounted on the mmt. Is this just over-doing it on the strength? Will one side of the mmt be able to handle the stress of the shock cord?

kcobbva

So I fly both GPS and RF tracker. At LDRS the my hand held GPS receiver and phone quit working, so off to RF which tracked the rocket in flight and then it quit once on the ground for some odd reason. We had the same issue with it in a subsequent rocket. Anyway, I ALSO have an EPOSGEAR attached to the nosecone. https://www.amazon.com/dp/B00NSOBY00/?tag=skimlinks_replacement-20 I'll tell you I was about 200 yards away when I started hearing it and I had NO issue finding it. I will fly that in all my rockets going to high altitude from now on (as long as it fits).

Last edited by a moderator:

NateLowrie

Well-Known Member
That actually sounds like a good idea. Would you think of using the TeleMini as a back-up for D-D and then using a Missle Works RRC3 as the main for D-D?
That would be a good combo. You might consider running a EggTimer TRS and the TeleMini as backup for DD. That way you get a 900Mhz GPS tracker and a 70cm RDF tracker without extra wiring or configuration. The TRS unit is $90, the LCD Reciever is another$40, and 3db whip antennas on each end would be another \$30. All of which is very reasonable in total and the LCD receiver is a one time investment.

BDB

Absent Minded Professor
So I fly both GPS and RF tracker. At LDRS the my hand held GPS receiver and phone quit working, so off to RF which tracked the rocket in flight and then it quit once on the ground for some odd reason. We had the same issue with it in a subsequent rocket. Anyway, I ALSO have an EPOSGEAR attached to the nosecone. https://www.amazon.com/dp/B00NSOBY00/?tag=skimlinks_replacement-20 I'll tell you I was about 200 yards away when I started hearing it and I had NO issue finding it. I will fly that in all my rockets going to high altitude from now on (as long as it fits).
Kevin, What happened with your GPS at LDRS? Just curious....

Last edited by a moderator:

DeltaFuturistics

Active Member
Quick update on this project:

I decided on purchasing a TeleGPS for the kit, TeleBT, and a Yagi antenna. The TeleGPS will make its debut in the 38mm MC FG Tomach that I completed a while ago and fly in the summer. Still have not decided on getting a RF or another GPS system as a backup. The kit will most likely have a RRC3 and another altimeter to be decided as back up. Possibly an Easy Mini.

I have ordered the shock cords from One Bad Hawk.

Almost all is ready to go for this kit to get built, hopefully, it flies before October.

Does anyone know a good supplier of 1inch Kevlar Strap? I need this for Shock Cord to Motor tube attachment. I might email One Bad Hawk and see if they can supply me with a strap.

Quick update on this project:

I decided on purchasing a TeleGPS for the kit, TeleBT, and a Yagi antenna. The TeleGPS will make its debut in the 38mm MC FG Tomach that I completed a while ago and fly in the summer. Still have not decided on getting a RF or another GPS system as a backup. The kit will most likely have a RRC3 and another altimeter to be decided as back up. Possibly an Easy Mini.

I have ordered the shock cords from One Bad Hawk.

Almost all is ready to go for this kit to get built, hopefully, it flies before October.

Does anyone know a good supplier of 1inch Kevlar Strap? I need this for Shock Cord to Motor tube attachment. I might email One Bad Hawk and see if they can supply me with a strap.
It is absolutely incorrect that you can't have a rock solid eye bolt mount
on the top centering ring of a 54mm mount in a 3" airframe..
I have 3/16" stainless welded eyes just for this purpose..

Who are you Delta ??
Is the order I have right now for 1 each 2 loop and 3 loop 11/32" Tubular Kevlar from you ???

Teddy

DeltaFuturistics

Active Member
It is absolutely incorrect that you can't have a rock solid eye bolt mount
on the top centering ring of a 54mm mount in a 3" airframe..
I have 3/16" stainless welded eyes just for this purpose..

Who are you Delta ??
Is the order I have right now for 1 each 2 loop and 3 loop 11/32" Tubular Kevlar from you ???

Teddy
Yep that's me. If I can use an Eyebolt than I'd rather go with that method. I noticed you ran it on your own 3inch with a 54mm. Did you just use one eyebolt? To be honest I might just use the forward closure of the aerotech engine and run the eyebolt in their if you feel that it would be sufficient enough.

Yep that's me. If I can use an Eyebolt than I'd rather go with that method.
I need the measurement from the top centering ring to the top edge of the booster...
The harness on this eye will be a few inches shorter then that measurement..
Something is going to wear against the sharp edge of the booster..
You'd rather that be the easy to service / access harness rather then extremely difficult to access eye attachment...

Ima shoot you an email....

Teddy