L3 "Sugar Daddy"

[Gunny]

Here is my 12” upscale Big Daddy, the “Sugar Daddy”. Has a 5” motor mount and stands 7 feet tall. Also has on-board video.

I flew the Sugar Daddy on a M1315 for my L3 cert, weighed 75 lbs on the pad. The L3 cert was a success.

Check out the build and flight pics on the TTA web site, some cool videos too.

https://www.trailertrashaerospace.com/sugar_daddy.htm

 

[daveyfire]

Awesome stuff, Marty! I haven't been to the TTA page in a while... looks like you guys are kicking some butt with those sugar motors! 5" diameter... WOW!

 

[rstaff3]

What he said! I am a regular visitor to your site and really admire the work you are doing. Makes me want to pack up and move west

Congrats on your cert!

 

[Smokin' Rockets]

.Congrats! Great rocket and great flight Marty. Video is awesome.

Curious how much nose weight it needed. I would guess about 15#?

....Bill

 

[SpartaChris]

I saw you fly that baby at GHS. Great looking rocket!

-Chris

 

[gerbs4me]

sweet looking rocket
awesome launch pics, the name is cool too

 

[Gunny]

Thanks guys, I slept so good that night.

Actually Bill, in a way, your guess on the nose weight is correct. The entire none cone weighs 15 pounds. That big chunk of basswood that was turned down for the tip is 6.5 lbs. The rest of the NC is a hollow, three tier telescoping, chamber made of tubes and centering rings. Half of the 24-foot chute and recovery leash was positioned inside it.

 

[Smokin' Rockets]

Another question to get some knowledge. Did you use barrowmans(rocksim, VCP, etc) to get the CP/CG right, or scale up the known CG of the original BD?

I know those programs dont work on my Chubsy (upscale fatboy). I just upscaled the known CG of the FB on a C motor.

If you used Rocsim did you fly it with a full caliper of stability or less.

Thanks.....Bill

 

[GL-P]

Sweeeeeeeeeeeeeeeeeeeet!!!

(Ha ha!!)

 

[Gunny]

I used RickSim to locate the CP and then Barrowman for cross-reference. Using only the CP from the 2D DWG, the actual CG came in at around ¾ caliper… I went with it. There’s something to be said about those short stubby rockets with all that fin surface.

Although most of my builds are scratch, your Chubsy (custom) was my second kit. I put a 3” MM in it and used the long PML cone. Put an avionics bay between two fins with a hatch, it has over 20 flights on full L and baby M candy motors. It’s a local favorite, everybody loves the Chubsy!

 

[North Star]

Thanks for an excellent post which has helped me quite a bit. I have a very similar design for my L3 (when we can get the motors over here ) and I was unsure how I was going to configure the nose (mine is stock 12" PML parts). I was going for a payload bay inside the nose but I'm going to re-arrange that to incorporate a chute deployment tube. You've also reassured me about putting the electronics between the fins. I wasn't sure how much turbulent air there would be but you don't seem to have had any problems.

I've always liked the short stubby designs, the low and slow(er) flights make for a real spectacle.

 

[solrules]

Originally posted by North Star
You've also reassured me about putting the electronics between the fins. I wasn't sure how much turbulent air there would be but you don't seem to have had any problems.

Thats because GWIZ flight computers are accelerometer based, and need no vent hole, and are not effected by turbulance between the fins. The MC has a baro sensor, but is only used for deployment of a main chute when the rocket is on drogue, so the baro is going to get odd readings no matter where it is placed. If you are using a baro based altimeter, you may want to reconsider putting it in the fin can.

 

[FredA]

You NEED vent holes for the baro to function.

Without proper venting, you are likely to miss your main deployment altitude....by how much is anybody's guess.

Agree that it's not used for apogee detection.

I can't think of any flight computer that does not require venting.

 

[solrules]

Originally posted by freda
You NEED vent holes for the baro to function.

Without proper venting, you are likely to miss your main deployment altitude....by how much is anybody's guess.

Agree that it's not used for apogee detection.

I can't think of any flight computer that does not require venting.

Whoops. I meant that the flight computers don't need a vent hole for apogee....

The lowest cost unit from GWIZ does not need venting, but it does not do dual deployment.

 

[North Star]

I have a G-Wiz LC deluxe and I would want the option of dual deployment - I have a Blacksky ARRD (though looking at "Sugar Daddy's" altitude I might get away with apogee only- even over here with our smaller sites). I also have other electronics I would use as backup.

With such a short rocket I would think that the airflow will be distubed throughout the surface of the body tube due to the lack of space between the nose cone and the fin can. After apogee the whole booster would be in disturbed air anyway. I could incorporate a vent tube to some other area. Do you think that would help?

 

[Gunny]

Brian,

My Chubsy rocket has flown 15 flights using the Missile Works RRC2 (baro only) altimeter. The apogee deployment was not consistent, little early or little late, but was acceptable. To make it work I drilled a single ½” hole thru each of the fin tabs inside the fin can and drilled ¼” vent holes in the BT hatch cover and between the other fins accordingly.

https://www.trailertrashaerospace.com/chubsy.htm


As you well know, when building short fat rockets your options are limited. If you’re going with your G-Wiz LC deluxe for apogee and low deployment (dual) with the ARDD, then the (Chubsy) methodology described above would probably work nicely. The venting requirements while under drogue are not that critical, just as long as you have some.

I’m considering putting an ARRD in the Sugar Daddy and going dual deploy as well. I’m looking at much more altitude on the TTA 5” candy motors. I won’t need to worry about venting for low deploy because there’s a gaping hole in the avionics bay where the video camera sticks out the hatch cover.

 

[North Star]

Marty .... thanks for the info and (like I said earlier) thanks for a very useful post .. I've had a good look at your website and I feel ....

Inspired



Short Fat Rockets Rule