2 Stage I to G flight

[AidanY]

Hello everyone!

This past saturday I flew a 2 stager, I245G to G76G. 54mm booster to 38mm sustainer. Both stages recovered and the sustainer reached 7906 feet. Everything was successful except the main parachute not fully comming out of the nosecone resulting in 2 broken fins on impact.

Electronics were 3 eggtimer quantums. One in the booster and two in the sustainer. There was a 1g charge for stage seperation right after motor burn out and 2.5 second coast on the sustainer.

The sustainer casing(aerotech hobbyline 29/40-120 casing) was modified for HEI(Head End Ignition) by simpilly potting the igniter into the foward closure. This worked flawlessly.


Tracking in the sustainer was done with a eggfinder mini and the booster was tracked with a BMK radio beacon paired with a 7 element yagi antenna on the reciever.


Build and launch photos.
The blue interstage here was later swapped to a new design.

The change that was made was insetting the sustainer into the booster airframe section allowing the full stack to be much more rigid essential for a straght flight.

The booster fincan

The booster fincan was mounted in a way to allow free rotation of the fincan to reduce spinning on the boost stage.


Launch day:
View attachment _IMG1451.JPG
View attachment TST Flight Video.mp4

 

[AidanY]

Full Flight Breakdown

Booster seperation: @1.5s, 650 feet
Booster apogee: @11.7s, 2467 feet
Booster total flight time: 104.20s

Sustainer ignition: @4s, 1828 feet
Sustainer apogee: @24.05s, 7906 feet
Total flight time: 138.05s

*Times are from time of launch.

 

[waltr]

Great flight, congrats.

 

[cerving]

Nice flight! Did you time that sustainer ignition delay, or did it just take awhile to light? My guess is that's the latter, since it looks like you used a FirstFire igniter, and they do take a few seconds to light...

 

[AidanY]

Nice flight! Did you time that sustainer ignition delay, or did it just take awhile to light? My guess is that's the latter, since it looks like you used a FirstFire igniter, and they do take a few seconds to light...

The sustainer was set to ignite 4s after launch. The booster motor would burn for 1.5s so this would allow for a 2.5s coast. Looking at the data, the sustainer ignited at around 5s. So it was more of a 3.5s coast.

 

[pugachu]

Good job on the flight. How hard is it to remove the potting on the fwd closure? Did you use epoxy?

 

[AidanY]

Good job on the flight. How hard is it to remove the potting on the fwd closure? Did you use epoxy?

The igniter was potted into the foward closure with proline epoxy. It can be reused by drilling out the old igniter and potting in a new one. On my next stager, the igniter will just be potted into a cyliner of epoxy and replace the smoke grain.

 

[SkiesAreClear]

Great flight! Did you use a separate battery in the Quantum for sustainer ignition or use a single battery? Which battery did you use?

 

[AidanY]

Great flight! Did you use a separate battery in the Quantum for sustainer ignition or use a single battery? Which battery did you use?

Single Battery on the Quantums. I used Turnigy nano-tech 300mAh 2S 35~70C Lipos.

 

[StreuB1]

Great Job, Aiden, and really nice flight!! I like your setup as well. You took the KISS principal and had success.

I like the airframe block and the rotating fin can; Jim Jarvis I am most certainly sure would smile at it. I think you might be the first person to make one this small and in the most simple manner possible. Looks like it worked perfectly!

A+ on using Quantum's, so small, simple, and versatile. I have several of them. Can't really go wrong with them!

How did you mate the sustainer and the booster? Care to post up some pics of the interstage and your methods? I am sure many others entering staging would appreciate the additional info. You project here would be a great starter for people to get into staging. Very good project, robust, easy to implement, compact.

Good idea on making a reusable/removable HEI plug insert to carry your ignitor in the forward closure. If you can find a machinist, making an aluminum plug with an o-ring might be more robust but hey, doesn't need to be complicated to work!

Keep at it and keep us in the loop!

 

[AidanY]

Great Job, Aiden, and really nice flight!! I like your setup as well. You took the KISS principal and had success.

I like the airframe block and the rotating fin can; Jim Jarvis I am most certainly sure would smile at it. I think you might be the first person to make one this small and in the most simple manner possible. Looks like it worked perfectly!

A+ on using Quantum's, so small, simple, and versatile. I have several of them. Can't really go wrong with them!

How did you mate the sustainer and the booster? Care to post up some pics of the interstage and your methods? I am sure many others entering staging would appreciate the additional info. You project here would be a great starter for people to get into staging. Very good project, robust, easy to implement, compact.

Good idea on making a reusable/removable HEI plug insert to carry your ignitor in the forward closure. If you can find a machinist, making an aluminum plug with an o-ring might be more robust but hey, doesn't need to be complicated to work!

Keep at it and keep us in the loop!

The interstage is pretty simple. Its 3D printed in 2 peices, one for the actual interstage part and the other the avionics bay.

The two holes here are for 2 all threads to retain the avionics and the recovery.



The sustainer slides into the body tube and the fins that stick up are just for aerodynamics. The space underneath is for the seperation charge.

 

[kjhambrick]

Awesome !

Please tell us more about the spincan on your booster !

Thanks for posting @AidanY !

-- kjh

 

[AidanY]

Awesome !

Please tell us more about the spincan on your booster !

Thanks for posting @AidanY !

-- kjh

The spincan is just the fincan mounted onto a coupler. The coupler is retained to the airframe by a screw.

The entire system is 3 parts the fincan, coupler, and the rest of the airframe.

The 38mm motor goes into the coupler.


Fincan slides onto the coupler

coupler is than screwed into the airframe, also a good place to mount a rail button.

 

[bad_idea]

The spincan is just the fincan mounted onto a coupler. The coupler is retained to the airframe by a screw.

The entire system is 3 parts the fincan, coupler, and the rest of the airframe.

Fincan slides onto the coupler

coupler is than screwed into the airframe, also a good place to mount a rail button.

I really admire the simplicity and efficacy of your design. Kudos.

 

[JPL]

Yes, very nice design!

 

[gdjsky01]

Care to share the files for the ISC?
Nice work BTW!!!

 

[BABAR]

The spincan is just the fincan mounted onto a coupler. The coupler is retained to the airframe by a screw.

The entire system is 3 parts the fincan, coupler, and the rest of the airframe.
View attachment 610209
The 38mm motor goes into the coupler.
View attachment 610210

Fincan slides onto the coupler
View attachment 610211
coupler is than screwed into the airframe, also a good place to mount a rail button.
View attachment 610212

nice!

is there any lubrication between the fin can and the coupler?

 

[AidanY]

nice!

is there any lubrication between the fin can and the coupler?

There is not. The fin can spins pretty freely already.