Keeping It Low: What Approach Do You Prefer for Flying in Small Fields?

[mh9162013]

As a life long rocketeer, go-kart racer and motorcyclist, I love little more than loud noises and stinking smoke! So, to enhance my fleet of low flying odd-rocs, I built some BT-80 and BT-70 models with stonking E and D motors, but to fly only to a low altitude.

View attachment 614499
Three smokey, noisy low flyers, E and D powered. All are equipped with trailing edge flaps on one side of the fins to induce rapid spin. This extra drag reduces altitude and increases stability, making for perfect flights, easily visible to one and all.

View attachment 614501

Not a fan of going with a big rocket and using bigger D and E engines (too expensive), but I do like the idea of the trailing edge flaps!

 

[Azamiryou]

I go both ways, small rockets with small motors, big rockets with big (but not huge) motors. I got 4' launch rods to give the big rockets more time to get up to speed on smaller engines.

I like the big rockets a lot - easy to see and watch, plus the big noise and smoke are exciting. "Majestic" is the adjective I try for.

Small rockets are great, too — fast is exciting, and 200' looks higher when the rocket is small. Streamer recovery means you can go even higher if the winds are light enough. Best of all, the engines are cheaper.

Don't overlook saucers and other draggy designs and oddrocs, either.

 

[mh9162013]

I go both ways, small rockets with small motors, big rockets with big (but not huge) motors. I got 4' launch rods to give the big rockets more time to get up to speed on smaller engines.

I like the big rockets a lot - easy to see and watch, plus the big noise and smoke are exciting. "Majestic" is the adjective I try for.

Small rockets are great, too — fast is exciting, and 200' looks higher when the rocket is small. Streamer recovery means you can go even higher if the winds are light enough. Best of all, the engines are cheaper.

Don't overlook saucers and other draggy designs and oddrocs, either.

What kind of apogees do you get with your BT-70 and BT-80 "park" flyers?

 

[Azamiryou]

What kind of apogees do you get with your BT-70 and BT-80 "park" flyers?

I don't have any over BT-60 except Big Daddy. My "Big" rockets (24mm mount) are BD, ProtoStar, and Astron Explorer. I haven't used altimeters, but they all fly fine with Estes C11 on a 4' rod.

 

[Dotini]

What kind of apogees do you get with your BT-70 and BT-80 "park" flyers?

With my BT-70 and BT-80 models depicted, I'm getting no more than ~500' at best. They waste a lot of energy in spinning. But they are quite spectacular.

 

[mh9162013]

With my BT-70 and BT-80 models depicted, I'm getting no more than ~500' at best. They waste a lot of energy in spinning. But they are quite spectacular.

That's pretty high for my area, as I try to keep things under 200 feet (I get nervous once I hit 250). Will these rockets work with C11 engines?

 

[Dotini]

That's pretty high for my area, as I try to keep things under 200 feet (I get nervous once I hit 250). Will these rockets work with C11 engines?

That's a good thought, because some but not all will. But don't be tempted to exceed the 6 oz. limit for this (excellent) motor. I find it very useful for BT-60 and BT-55 models. It's very easy to exceed this limit if you want a nice paint job.

The good news is, if you build in vigorous spin, the model will always want go up straight and not stray from course.

IMHO, an X-form parachute will help ensure your model comes down as close to the pad as possible.

 

[Azamiryou]

With BT-60 and larger, a chute release (JLCR) is a good way to keep those 400'-500' flights on the field — let it plummet most of the way down and open the chute at 100' over the field.

 

[bjphoenix]

As a life long rocketeer, go-kart racer and motorcyclist, I love little more than loud noises and stinking smoke! So, to enhance my fleet of low flying odd-rocs, I built some BT-80 and BT-70 models with stonking E and D motors, but to fly only to a low altitude.

I'm working on a simple BT-70 build right now to keep the altitude a little lower than my BT-60 rockets such as HiFlier XL.

 

[4regt4]

I'm working on a simple BT-70 build right now to keep the altitude a little lower than my BT-60 rockets such as HiFlier XL.

I just finished putting decals on a Hi Flier XL. It's going up on a D12 in a couple days. I did add a payload bay to carry an altimeter and Marco Polo for when I get stupid and put an "F" in there.

Hans.

 

[Dotini]

Not a fan of going with a big rocket and using bigger D and E engines (too expensive), but I do like the idea of the trailing edge flaps!

The flaps are easy to install at any time. They will theoretically work even when the height of the flap is as little as 2% the chord of the fin!
I too am not an intensive fan of bigger engines, but do enjoy them sparingly.

Accordingly, my latest project is a two stage rocket with altimeter utilizing Estes's most humble motors, the A8-0 and the 1/2 A6-2. The goal is to find the smallest field from which I can routinely launch and recover these vehicles.

 

[jmasterj]

With BT-60 and larger, a chute release (JLCR) is a good way to keep those 400'-500' flights on the field — let it plummet most of the way down and open the chute at 100' over the field.

If D motors are out of the OP's budget, I don't think he's interested in a JCLR.

 

[bad_idea]

It does. If you want one of those for, say, an Alpha upscale, it's half the price of a Patriot kit. BTW, the fineness ratio of that cone is not exactly right for a scale Patriot, so the Estes kit is sport scale only.

What's the aspect ratio? Looks not too far off 3:1, so about right for a Doorknob or a Small Daddy.

 

[SolarYellow]

 

[bad_idea]

View attachment 614634

Thanks. Close enough for me. You may have spent some more of my money.

 

[SolarYellow]

Just get that printer fired up, man!

 

[SolarYellow]

Old thread, but it occurs to me that the Curvilinear is pretty much designed to answer the OP's question.

https://www.erockets.biz/estes-flying-model-rocket-kit-curvilinear-est-3231/
Also the cheapest source for that nose cone if you want to use it for something else.

Build blog starts here:

https://modelrocketbuilding.blogspot.com/2017/10/estes-curvilinear-background.html

 

[bad_idea]

Just get that printer fired up, man!

Indeed. In the meantime resisted FOMO on that discontinued kit for its nose cone, since I realized the Apogee PNC-41.6 is a better match even if I don't get the printer going until the year 2300. Still trying to resist FOMO on that kit as a good small-field flyer, but since I vastly prefer to scratchbuild, good sense will probably prevail.

Re. small field flying, it's been my intent for some time to build a park flyer with a detachable ring fin (possibly angled to act as a drag brake) to keep it low when I need to. After reading through this thread though, I might go with @Dotini 's detachable spin flaps instead. Cool effect plus good way to get practice analyzing spin data.

 

[SolarYellow]

I might go with @Dotini 's detachable spin flaps instead. Cool effect plus good way to get practice analyzing spin data.

I wonder if they make it want to spin while it's still moving up the rod. Could that lead to additional rod whip?

 

[4regt4]

I wonder if they make it want to spin while it's still moving up the rod. Could that lead to additional rod whip?

I know (the hard way....) that the Rocketarium Vortico will grab the launch rod if placed too far below the end. I had one take the rod with it for a ride.

Hans.

 

[Dotini]

I wonder if they make it want to spin while it's still moving up the rod. Could that lead to additional rod whip?

I've never seen rod whip in my launches. I use cold rolled steel rods that are 42" long. I use two widely spaced lugs, and they are one size up - so a loose running fit on the rod. As the model accelerates on up, the spin rate visibly increases by about 20' up. With the Vortico, I use a stubby rod of 24".

 

[BABAR]

Accordingly, my latest project is a two stage rocket with altimeter utilizing Estes's most humble motors, the A8-0 and the 1/2 A6-2. The goal is to find the smallest field from which I can routinely launch and recover these vehicles.

I’ve seen A8-0 stage before booster got off the rod. Looked for the **%%#} thing for 10 minutes before I finally looked at the pad.

 

[86mustang408w]

I start out every time with no excuses, my Estes Tigres on a A8-3, then B, then C as a test flyer for 18mm rockets, and a 24mm High-FlierXL I also use as a test flyer. After that I see where it lands, and go higher or home. Chute releases or DD could help too for small areas and higher flights.

 

[86mustang408w]

I've never seen rod whip in my launches. I use cold rolled steel rods that are 42" long. I use two widely spaced lugs, and they are one size up - so a loose running fit on the rod. As the model accelerates on up, the spin rate visibly increases by about 20' up. With the Vortico, I use a stubby rod of 24".

When you get to heavier bigger rockets that have low thrust to weight ratios you will see rod whip.

 

[cwbullet]

When you get to heavier bigger rockets that have low thrust to weight ratios you will see rod whip.

Use a rail, then a low risk of whip.

 

[86mustang408w]

Use a rail, then a low risk of whip.

I do, thank you.

 

[dmaaero]

Here is a few you can keep under 200'
Black Brant 2 115-339'
bull pup 127-337'
Patriot 97-275'
Niki X 96-260'
Tigres 192-511'
Baby Bertha 54-175'
Aspire 116' with a A8-3 or 5194' with a F10-8

 

[smstachwick]

I’m going to do some rough proportions with Estes apogee predictions and certified impulse values. These numbers might be a tad higher than real-world.

220 Swift: 283ft on a 1/4A3-3T

Wizard, Viking, and Xtreme: 200ft on a 1/2A6-2

Black Brant II: 688ft on a C11

Hi-Flier XL: 438ft on a C11

Saturn Skylab: 269ft on an E16

 

[mh9162013]

Wizard, Viking, and Xtreme: 200ft on a 1/2A6-2

I get about 190 feet on an A8-3 with my Wizard, Yankee and Viking rockets.

I build heavy, what can I say.

 

[Azamiryou]

I get about 190 feet on an A8-3 with my Wizard, Yankee and Viking rockets.

I build heavy, what can I say.

I don't think my Xtreme goes anywhere near 200' on a 1/2A6. I haven't flown it with an altimeter, but my eyeball believes it goes a wee bit over 100'.

I'm doing a park launch Monday, I'll try to remember to send my altimeter up on as many flights as possible to get some low altitude data.