How small is too small for a camera?

I have successfully attached an 808 keychain camera to several rockets that were about 2 feet tall and the camera didn't affect stability at all. So I tried taping one to the side of a 12" Estes Hi-Flyer. Bad idea. It was totally unstable, never got more than 15 feet off the ground and bounced off the parking lot multiple times. Below are before and after pictures.

What is the smallest rocket that you have attached a keychain camera to without stability problems?

I've flown one on a BMS School Rocket. The SR definitely knows the camera is there as the flight path is affected....but it's still stable. I mounted them at about the CG.

The hi flyer is already a little suspect on the stability scale without adding a big lump on the side of it

Remember that the further forward you put the additional weight, the more you move the CG forward, increasing stability. Putting it at or near the CG does NOTHING to improve stability, but it actually decreases it in practice, because the rocket is heavier... so therefore it is slower, and thus generates less corrective forces from the fins. In addition, the "bump" on the side throws the CG off to one side, as well as messing with the clean flow of air over the fins, all of which decreases stability.

I'd suggest that you use a SLIGHTLY bigger rocket... and that you mount the camera as far forward as practical.

Later! OL JR

I launched an Estes RTF Skytrax on a C6-5 with an 808 strapped to the side and even that had a pretty pronounced lean in it's flight path. That rocket is typically a straight up rocket

The Estes skywriter is great for these cams since it does not spin if the cam is mounted carefully on the tube joint.

I have flown a scratch tube fin rocket 3 times, all perfect flights, I put on my camera and it went wayyyy off in a ballistic trajectory. i found it like 500 feet away.

It did have some good video of the crash tho.


I then flew the rocket again(2 inches shorter) with no camera, PERFECT flight. It was 28 inches tall with Bt60 fins and body, flown on a C6-3, weight of(i believe) 4.5 ounces.

[POW]Eagle159;388210 said:

...weight of(i believe) 4.5 ounces.

Click to expand...

That is pretty heavy for a C6. The camera was probably more of a weight issue than an aerodynamic effect.

BT50 flown by a D5 (Quest) in a Blue Bird Zero clone was the smallest. BT55 rockets powered by B6 and above worked fine too.

paul.nortness said:

The hi flyer is already a little suspect on the stability scale without adding a big lump on the side of it

Click to expand...

This is true. A little too much glue on the fin can and stability is an issue

OP, did that configuration pass a swing test? I tend to doubt it.
Don't fly a scratch-build (or a modified kit) without one until you have done a lot of successful scratch-building. It's a fundamental piece of test data.

I have to imagine if you pulled the "guts" of a camera pen out and mounted it inside the smallest diameter it would fit into, that would be the narrowest. Although it might be an outward looking view, it would be a video camera in a rocket. I have yet to launch a rocket with a camera of any sort, but I'm up for the challenge. I am going to find the smallest cost appropriate camera I can find, fit it and fly it in the smallest rocket I can safely build. It might be a few weeks,,, but I'll be back here with results...

Cheapest results of my pen video camera search :
https://www.google.com/products/cat...a=X&ei=Kc5DUNbLMKGriALc8YDYCQ&ved=0CHgQ8wIwAg

spacecadet said:

OP, did that configuration pass a swing test? I tend to doubt it.
Don't fly a scratch-build (or a modified kit) without one until you have done a lot of successful scratch-building. It's a fundamental piece of test data.

Click to expand...

Good idea, I didn't swing test the Hi-Flyer with or without the camera attached. That crash was the first flight of that rocket and I wondered how stable it would have been without the camera. So I repaired the body tube with some clear packaging tape and launched it with a C6-7 engine and no camera. It flew perfectly straight up, out of sight, and I never saw it again.

WizardOfAZ said:

I have to imagine if you pulled the "guts" of a camera pen out and mounted it inside the smallest diameter it would fit into, that would be the narrowest. Although it might be an outward looking view, it would be a video camera in a rocket. I have yet to launch a rocket with a camera of any sort, but I'm up for the challenge. I am going to find the smallest cost appropriate camera I can find, fit it and fly it in the smallest rocket I can safely build. It might be a few weeks,,, but I'll be back here with results...

Cheapest results of my pen video camera search :
https://www.google.com/products/cat...a=X&ei=Kc5DUNbLMKGriALc8YDYCQ&ved=0CHgQ8wIwAg

Click to expand...

Yep, John Pursley launched one of these very rockets as a two stager powered by mini-motors (13mm) motors a couple months back at the last Shiner launch... Worked pretty well. It all fit inside a 13 mm tube once you gut an ink-pen camera... He made a mini-mirror hood for it, which can be removed for just "straight out" shots as well.

Later! OL JR

WizardOfAZ said:

I have to imagine if you pulled the "guts" of a camera pen out and mounted it inside the smallest diameter it would fit into, that would be the narrowest. Although it might be an outward looking view, it would be a video camera in a rocket. I have yet to launch a rocket with a camera of any sort, but I'm up for the challenge. I am going to find the smallest cost appropriate camera I can find, fit it and fly it in the smallest rocket I can safely build. It might be a few weeks,,, but I'll be back here with results...

Cheapest results of my pen video camera search :
https://www.google.com/products/cat...a=X&ei=Kc5DUNbLMKGriALc8YDYCQ&ved=0CHgQ8wIwAg

Click to expand...

You can get higher resolution ones for much less than that on eBay: https://www.ebay.com/sch/i.html?_sacat=0&_nkw=spy+pen+camera&rt=nc&LH_BIN=1 I've got one that works pretty well, but I would recommend putting a high-class memory card in it.