Drogue vs. Streamer for DD

[LANZA COLINA]

I am putting together my first dual deploy attempt and am wondering what pros/cons people have had using a long streamer in place of a drogue parachute. I'll be flying fairly high but still under 10,000 feet but without onboard GPS/tracking and I think using a streamer will make it a bit easier to see the rocket coming down. Any help/advice would be appreciated. Thanks!

 

[Steve Shannon]

I am putting together my first dual deploy attempt and am wondering what pros/cons people have had using a long streamer in place of a drogue parachute. I'll be flying fairly high but still under 10,000 feet but without onboard GPS/tracking and I think using a streamer will make it a bit easier to see the rocket coming down. Any help/advice would be appreciated. Thanks!

The main issues I’ve seen with streamers are the fact that they don’t slow the rocket enough and they sometimes tangle the main.

 

[Antares JS]

Streamers are only suitable for smaller rockets. A drogue keeps your payload section under control so it's not whipping around randomly and firing your main straight down or towards the booster.

I've learned this from my TAPs while working on my Level 3 rocket and then saw it in action on my prototype.

 

[doug_kosty]

Or, depending on the size of your rocket, you can simply go drogueless. And streamerless. Not sure where the limits are, but for rockets of a few pounds this seems to work well.

 

[tim cubbedge]

Well I have seen some pretty big streamers used in HP rockets. Two guys use them regularly at my club. Biggest advantage is visibility. These rockets were using 80-100 feet in streamer length. Could be seen from great distances. Biggest problem with using such a big streamer is packing space. If not properly positioned they can get tangled up with the main but I think these guys at my club have it dialed in.

 

[Sooner Boomer]

I plan on using a ribbon drogue on my L2 rocket. As you say, mostly for visibility in tracking on the way down. I'm using a JLCR, and the drogue/ribbon will be released ( let go from rocket) when the JLCR opens to reduce the chance of tangling with the main.

 

[Not Quite Nominal]

I am putting together my first dual deploy attempt and am wondering what pros/cons people have had using a long streamer in place of a drogue parachute. I'll be flying fairly high but still under 10,000 feet but without onboard GPS/tracking and I think using a streamer will make it a bit easier to see the rocket coming down. Any help/advice would be appreciated. Thanks!

Streamers have about one fifth the drag of a parachute - and less, if it's a high aspect ratio streamer.

That's a good thing and a bad thing, depending on how much room you have.

If you're limited by the space available, you might not be able to get enough streamer to slow you down enough to get a stable upside-down V configuration.

If you're not, it's a huge, highly visible thing that's not slowing you down too much. I love them in that application.

Me on drogues

My (controversial) take is that your drogue should be sized to match the surface area, not weight, of your rocket. Once the drogue provides about the same drag as the rocket body, you'll get your ^ configuration. A streamer equal in area to the side profile of the rocket seems to work well for me.

 

[Pete.D]

I've had great success with motor eject near apogee, streaming a JLCR-wrapped main until release at low altitude. But I mainly launch MPR; I'm relatively new to really heavy HPR rockets. I think that for heavy rockets some kind of drogue would be required to keep the decent rate under control. Visibility at more than a couple thousand feet is a problem for me too; I like to see my rocket even with a tracker in play. I've never used a streamer with a big rocket, but Tim's picture looks great! That's a solution if the tangling/thrashing problem can be resolved.

 

[Pete.D]

I plan on using a ribbon drogue on my L2 rocket. As you say, mostly for visibility in tracking on the way down. I'm using a JLCR, and the drogue/ribbon will be released ( let go from rocket) when the JLCR opens to reduce the chance of tangling with the main.

I hadn't thought about completely releasing the drogue and streamer; great idea!

 

[mo2872]

Paging Stacy Worley.......Chimera video needed, STAT!!!

 

[Pete.D]

Streamers have about one fifth the drag of a parachute - and less, if it's a high aspect ratio streamer.

That's a good thing and a bad thing, depending on how much room you have.

If you're limited by the space available, you might not be able to get enough streamer to slow you down enough to get a stable upside-down V configuration.

If you're not, it's a huge, highly visible thing that's not slowing you down too much. I love them in that application.

Me on drogues

My (controversial) take is that your drogue should be sized to match the surface area, not weight, of your rocket. Once the drogue provides about the same drag as the rocket body, you'll get your ^ configuration. A streamer equal in area to the side profile of the rocket seems to work well for me.

I read your link; nice analysis! Of course the rocket's surface area must be considered when determining decent rate, unless the drogue is very much larger (like, to control decent of a small but high mass rocket).

But from the OP's perspective (and mine, I think) the streamer will have to be quite large to be visible at 10K+ ft. And, I like to bring the rocket down as quickly as possible due to limited field size and personal physical limitations (and I've never been to a field where it's permitted to recover a rocket using a motor vehicle).

 

[LANZA COLINA]

Thanks everyone for the help. This will help a great deal. My local club will be having a small launch at Black Rock several weeks after BALLS so driving to get my rocket shouldn't be an issue. With all of the smoke from the wild fires in the west visibility may be limited so I am trying to make it as easy as possible to spot my rocket as it is coming down.

 

[SEWAR]

I witnessed a streamer used on a sugar motor that was a huge rocket. The nice thing was the noise it made but it was falling very fast. I will incorporate a streamer and JLCR on the next scratch built rocket.

 

[Powderman]

I launched a modified DD 4" Punisher this last weekend and used a 10"x100' streamer from Rocketman in place of the drogue at apogee. Based on past experiences where the streamer got caught up in the main I moved the streamer to the AV Bay and the main chute to the booster. Both sections were pinned with 2-56 plastic screws to hold everything together. That flight went to about 6000ft. That streamer makes a big difference on visibility.

One thing I have noticed is that the streamer will make the rocket "plane" on the way down in one direction or another...it's not been terrible for us. I want to say our recovery was roughly 1/4 mile away.

Powderman

 

[Chad]

Streamers have about one fifth the drag of a parachute - and less, if it's a high aspect ratio streamer.

That's a good thing and a bad thing, depending on how much room you have.

If you're limited by the space available, you might not be able to get enough streamer to slow you down enough to get a stable upside-down V configuration.

If you're not, it's a huge, highly visible thing that's not slowing you down too much. I love them in that application.

Me on drogues

My (controversial) take is that your drogue should be sized to match the surface area, not weight, of your rocket. Once the drogue provides about the same drag as the rocket body, you'll get your ^ configuration. A streamer equal in area to the side profile of the rocket seems to work well for me.

this guy! it's always been in the back of my mind that drogue size should be determined by surface area. I knew i read it here somewhere but couldn't remember who said it.

At Airfest last year i saw a streamer that i swear must have been 50yds long. Rocketman makes some huge streamers like a 250ft one that is advertised with a 25fps decent rate for a 43lb rocket. I have a much smaller one with the only downside being, like you said, it takes up more space than a parachute.

One additional advantage to streamers is they don't drift as far as a parachute does. It's pretty much straight down.

https://the-rocketman.com/streamers/

 

[Brian H.]

I witnessed a streamer used on a sugar motor that was a huge rocket. The nice thing was the noise it made but it was falling very fast. I will incorporate a streamer and JLCR on the next scratch built rocket.

I believe that was my rocket if it was at Tripoli Southern Colorado just west of Pueblo, CO. Yes, it was a 4" diameter, 84" length, 11lb rocket coming down with a 6"x60" streamer that makes one heck of a noise at 90fps. We couldn't get eyes on it til the main deployed, but you could sure hear it.

 

[Brian H.]

The main concern with dual deploy is get the "inverted V" configuration (Booster and payload sections pointing away from each other with drogue harness forming vertex of the inverted V shape) while coming down after apogee deployment whether it be drogue parachute, streamer, or drogueless. It could take several test flights to determine the amount of drag to get the ideal inverted V configuration to deploy the main without the booster section tangling with the payload section.

I would lean towards less drag to start with. Drogueless or streamer for small diameter or lightweight rockets, small drogue chute for heavier rockets. I aim for 100fps decent rate under drogue, whatever it may be.

Simulation software like Rocksim or Open Rocket should give a fairly accurate decent rate under drogue.

 

[firemanup]

Have flown everything drogue less all the way up to 5” and 6” diameter 10 foot tall rockets 40-55 lbs and never had a problem. Descent rate always ends up around 100fps per GPS. Just food for thought on another option.

 

[JackC]

I find going drogue-less on any rocket under 4 inches in diameter and 20 pounds or less works well and cuts down on the drift that would occur even with a streamer.

 

[SEWAR]

I believe that was my rocket if it was at Tripoli Southern Colorado just west of Pueblo, CO. Yes, it was a 4" diameter, 84" length, 11lb rocket coming down with a 6"x60" streamer that makes one heck of a noise at 90fps. We couldn't get eyes on it til the main deployed, but you could sure hear it.

Yep… that was me!

 

[jd2cylman]

I’ve got a streamer in the drogue section of my WM 3” Interceptor. Awaiting initial flight to see if I like it.