Turbine Rocket Saucer

my monocopter routinely suffers burn through. My solution was to have as much of the aft end of the motor sticking out as possible, as the burn through is usually just forward of the nozzle.
a note of caution: E30s work well but the only E15 I used CATO'd presumably due to burn-thru.....and Art warns not to use anything reloadable...

Heheh, now that you have a working design, you must put lights on it for a night flight!!

Thanks for the kind words all.

falingtrea said:

Heheh, now that you have a working design, you must put lights on it for a night flight!!

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Yes, lights would be very cool.

I will not paint the thin FG outer ring so that internal LEDs can shine through. Later in the season CMASS plans to do a night launch and a lighted, spinning, clustered saucer would be a lot of fun.

terryg said:

So ... , when ya gonna stick some AP in there?

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I bought two ProX F30 3grain 24mm reloads at the launch which I plan to use again as central motors on my upscale Thunderbird.

Thought about using them to power this saucer but was concerned by the cost per flight and concern that the saucer might spin too violently and shred.

KPM61 said:

Why are the two motors burning through the side of the caseing in that last picture posted ?

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In posts 27, 29 and 34 fliers are noting that long burning motors in spinning rockets may be prone to burning through the outside wall of the motor.

Apparently there is enough centrifugal force to direct more of the engine's internal heat towards the wall of the motor away from the axis of spin.

This needs to be a kit.


N

delta22 said:

Thanks for the kind words all.



Yes, lights would be very cool.

I will not paint the thin FG outer ring so that internal LEDs can shine through. Later in the season CMASS plans to do a night launch and a lighted, spinning, clustered saucer would be a lot of fun.

Click to expand...

We're going to expect it so you can't back out now.

These would look nice.

Catching up on posts.

Mid-August, repaired the burns on the fins by doing several thin build ups of West 206 epoxy. Put wax paper on top of final build-ups to make them flat to fin surface.

Made 4.8 gram epoxy batches for these, the smallest batches of epoxy I have ever done. Any less and I would not have been able to mix it effectively with a popsicle stick.

Considered replacing the fins, but was concerned that removing them would cause further damage.

Three more good flights at the 8/28/10 CMASS launch in Acton, MA.

Each time on 4x D11-P clusters.

The 1.8 second engine burns with no delays or ejections made for clean flights with no burning of the rocket due to bad behavior by the engines.

Pictures of first launch of the day below.
The intense heat and sparks of the Rocketflite ML igniters is evident in the first picture. The fast spinning rocket with its spikes of flame seems to be sitting above the column of smoke. Interesting smoke starburst effect at the end of the burn. Rocket continues to lift and briefly hover after the burn.

Video of the second here:
https://www.bpasa.com/Movies2010/TRS7.wmv

Got in another flight, the saucer's 9th, on a beautiful day at the 9/18/10 CMASS Amesbury, MA launch.

Loaded up the Turbine Rocket Saucer with 8x D11-P motors and sent it up on a column of smoke and fire. With the 8 motors in the highly canted motor mounts, the rocket spun so fast it stripped off two of its motors in flight.

Pictures below, standard def video here (6MB):
https://www.bpasa.com/Movies2010/TRS9.wmv

High def video here (.mpg 23MB):
https://www.bpasa.com/Movies2010/TRS9-hds4.mpg

Also had the privilege of flying Carl Tulanko's beautiful, huge upscale Tres that day:
https://www.rocketryforum.com/showthread.php?p=133306#post133306

Very cool! Too bad 2 of the motors got torn off, but suppose it isn't too hard of a repair? Awesome pictures too,BTW!

Just ordered flexible strips of red and blue LEDs from the site Bill linked to earlier, superbrightleds.com.

Plan to put red on one side and blue on the other for what should be an interesting effect on a spinning rocket, day or night.

Pantherjon said:

Very cool! Too bad 2 of the motors got torn off, but suppose it isn't too hard of a repair? Awesome pictures too,BTW!

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The two motors were opposite each other, so I took it as a not-so-subtle sign that this was meant to be a 6 motor rocket.

Do you plan to have the LEDs on a manual switch or centrifugal switch?

It would be a fun surprise for spectators for the underside to suddenly start glowing red and blue just after the saucer starts spinning.

Just my :2:

G.D.

delta22 said:

Just ordered flexible strips of red and blue LEDs from the site Bill linked to earlier, superbrightleds.com.

Plan to put red on one side and blue on the other for what should be an interesting effect on a spinning rocket, day or night.

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I'm in the process of converting my large saucer for night flight - looks like about 220 LEDs:y:

BobCox said:

Very cool, Boris.

Last month I built an Art Applewhite cluster saucer, which comes with interchangeable motor mounts. I asked Art about using a canted cluster mount and he warned me against it. As you found out, a spinning saucer does not flip over during recovery and tends to land on its edge.

(Bit of irony -- as I posted this message, the Art Applewhite ad appeared on the top of the page.)

To get more altitude, I think you should either cant the motors more to get more spin so the turbine blades can provide the lift, or else cant the blades less so they have less drag during boost.

To get it to flip, maybe you could have a weighted nose cone with a shock cord about 6-10 feet long. When it pops off it would yank the saucer over and pull it down nose-first. By having a long shock cord, the weight would hit the ground first and give the rest of the saucer time to slow down before impact.


Another option: put angled deflectors on the top of the motors so that when the ejection charges fire, they slow down the rotation.

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So Bob, Do you have one on the work bench you haven't told me?

Turbine Rocket Saucer flew again at the CMASS Amesbury, MA launch 10/2/10.

It went up on 6x D11-P motors for its 10th flight.

Videos:
Standard def (4MB) https://www.bpasa.com/Movies2010/TRS10.wmv
High Def (12MB) https://www.bpasa.com/Movies2010/TRS10.mpg

The 175A fuse on my cluster box had failed, so there were a few false starts before we got the saucer up. I do not believe the fuse was blown, but was likely defective and suffered a mechanical failure.

On 11/6/10 two more good flights on 4x D11-P motors.

Has flown 12 times to date burning all 58 motors loaded.

Rocket is getting LEDs for a night launch opportunity coming up 11/20/10.

Got red and blue strips of these - Thanks for the link Bill.

billspad said:

We're going to expect it so you can't back out now.

These would look nice.

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Sanded and marked out locations for LED strips. Went with wraps that center on the ring ID (both ends at saucer outer edge) to help the LEDs to hold despite very strong centrifugal forces.

The LED strips I purchased have 60 LEDs on a 40 inch strip that can be cut at any 2" increment. They are rated at about 150mA (for 60 LEDs) at 12V.

Picked up a 11.1V 480mAh Lipo battery that weights only 1.4 oz.

Had to remove a clear, protective silicone covering on the strips, both to bend them as sharply as required and because the centrifugal force would have stripped them off anyway.

Cut the strips into 8" sections and used the sticky backing they came with to apply them to the saucer.

Soldered power wire from strip to strip around the ring ID, ending in a battery terminal near the center. Then painted LED strips and all wiring with two coats of West 206 epoxy to harden and adhere.

Went with one side red and one side blue to maximize visibility of spinning effect in flight.

I am very pleased with the results and look forward to flying with lights on both day and night going forward.

There are 96 LEDs on this total and the amount of light it throws off is surprising.

good news: Complete battery and light system added only 3oz to the rocket.
bad news: LEDs cost $50 and battery $30.

In theory the 480mAh battery will power the 240mA load for 2 hours. To preserve the battery will only use a fraction of this before recharging.

delta22 said:

On 11/6/10 two more good flights on 4x D11-P motors.

Has flown 12 times to date burning all 58 motors loaded.

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Boris,

This raises the question of an unbalanced thrust. Could we do a daylight test at the next CMASS launch? Maybe 4 motors loaded with only 3 ignited? At high-power pad B?

The LEDs look great. The 50-50 split should show the rotation best. See you Saturday.

KPM61 said:

Looks nice. A lot of light.
Are there lights on the bottom too ? Or just the top ?

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The 8 strips of LEDs each wrap completely around the outer ring with 12 LEDs each. This "UFO" throws off light in every direction.

KennB said:

Boris,

This raises the question of an unbalanced thrust. Could we do a daylight test at the next CMASS launch? Maybe 4 motors loaded with only 3 ignited? At high-power pad B?

The LEDs look great. The 50-50 split should show the rotation best. See you Saturday.

Click to expand...

One of my winter build plans is a modified version of this rocket.

After just investing some time and $ to cover this with LEDs I would like very much to see it fly at night.

While I believe the saucer would fly safely with imbalanced ignition, it may bend or damage my improvised launch platform.

The test you suggest is a good idea. What I propose is to do this (intentional off-balance cluster ignition) as my last flight of the day at the winter or first spring CMASS launch.

That way we can test this without running the risk of loosing the only night flight opportunity of the year.

delta22 said:

What I propose is to do this (intentional off-balance cluster ignition) as my last flight of the day at the winter or first spring CMASS launch.

That way we can test this without running the risk of loosing the only night flight opportunity of the year.

Click to expand...

I predict that the worst thing it will do is wobble on the way up. If only one motor fires you've got a monocopter type thing.

delta22 said:

What I propose is to do this (intentional off-balance cluster ignition) as my last flight of the day at the winter or first spring CMASS launch.

That way we can test this without running the risk of loosing the only night flight opportunity of the year.

Click to expand...

That's a great idea. After I posted my question I thought about the worst case scenario and how that would eliminate the night flight - no way do I want that to get disrupted.

The winter follies or the first spring launch would be much better. Maybe even a TARC launch.

I'd throw D12-7's or better yet D11-9s in that thing to give a realistic "Scale-like" scorched-earth landing pattern.
THAT would be entertaining !!!!

Turbine Rocket Saucer flew three more times on 11/21/10. Last CMASS launch of the season and an opportunity for night flights!

Got a bunch of great flight pictures. Unfortunately my video camera battery did last as well as I had expected, assume due to 30F temps, so no video.

The LEDs worked great!

This first TRS flight of the day was near dusk on 4x D11-P motors. Due to the 3oz weight added for lighting, altitude was slightly reduced to about 100ft.

To the eye, the red and blue LEDs blended to a smooth purple series of rings.

These pictures were taken at 1/3000 second exposure.

The fourth picture is at the end of the engine burn and offers an opportunity to roughly estimate saucer RPM:
> I estimate that the smearing or stretching of the LED light in the image reaches about 1/15 of the way to the next band of lights.
> The next band of lights is 1/8 of the way around the saucer.
> So the saucer completed 1/15 x 1/8 = 1/120 of a rotation in the 1/3000 second exposure. 3000/120 = 25 rev per second x 60 = approximately 1500 RPM

Next 11/21/10 TRS flight was at night on 6x D11-Ps and the effect was wild!

To the eye the saucer appeared as smooth white rings above a huge shower of flame and sparks.

These pictures offer another opportunity to estimate saucer RPM. Images were taken at 1/45 sec exposure (ISO 1600). Pictures were taken in a continuous series at 3 per second.
> Fifth picture was at 5 second onto the flight and colors overlap about 1/3 rotation (in 1/45 sec) so 15 rev per second x 60 = 900 RPM.
> Fourth picture is at 4 seconds onto flight and colors overlap almost 1/2 rotation so about 20 rev per second x 60 = 1200 RPM.
> Third picture is at tail end of motor burnout, end of effective motor thrust is about 1.6 seconds. With the loss of 300 RPM from second 4 to 5 and peak RPM at 1.6 seconds, I estimate roughly 2000 peak RPM.

2000 RPM estimate on 6x D11-Ps fits well with 1500 RPM estimate on 4x D11-Ps.

Third TRS flight on 11/21/10 and last flight of the season.

Also on 6x D11-P motors. Very similar to previous flight, these images cover first 2 seconds of the flight.

Awesome light effects and shower of flame and sparks!

Bill S. posted a video that includes this flight https://www.youtube.com/watch?v=J6PzqoEH9LQ

Turbine Rocket Saucer stats for first year of flight:

> Original design built spring 2010.

> Flown 15 flights firing all 74 motors loaded.

> All motors 24mm Estes BP, mostly D11-Ps.

> Flown on 4, 6 or 8 motors, seems to do best on 6.

> Always fired by Rocketflite MF igniters.

> Always used high output cluster box. Thread: https://www.rocketryforum.com/showthread.php?t=11766

delta22 said:

To the eye the saucer appeared as smooth white rings above a huge shower of flame and sparks.

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From where I was standing, after burnout the underside of the saucer looked mostly red. I was expecting it to look sort of purple. Maybe the red LED's were brighter than the blue?

That has got to be about the coolest rocket I have ever seen!