RRS Alpha, nozzle with graphite throat

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On June 4th at the MTA, Osvaldo and I launched an RRS Alpha with two features:

Lowering the RRS-Alpha into the launch rails at the MTA

Lowering the RRS-Alpha into the launch rails at the MTA

RRS-alpha loaded in the launcher rails

RRS-alpha loaded in the launcher rails

(1) refurbished alpha nozzle bored out to accept a graphite throat insert to demonstrate better performance in maintaining throat diameter and what could be better re-usability.

 

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(2) smoke charge in the payload section to aid in better visualization of the flight trajectory
lasix online

smoke grenade from PaintBall sports and vented payload segment

smoke grenade from PaintBall sports and vented payload segment

Loading the micrograin propellant mixture into the alpha propellant tube

Loading the micrograin propellant mixture into the alpha propellant tube

The empty alpha vehicle weighed in at 3.65 lbm, the loaded alpha vehicle weight was 6.55 lbm for a typical propellant load of 2.90 lbm.  I took some photos of the whole assembly and loading process just for illustration.  The process is very typical for the RRS alpha’s we fly.

The video linked below is of the countdown and launch.  Don’t blink.

RRSalpha-launch-160604
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Results were inconclusive until we can locate and recover (dig up) the rocket.  After some initial searching in the heat of the afternoon, I had to give up the hunt for the day.  I hope to get back out to the MTA and locate it and get pictures of the fired nozzle with the graphite throat.  Also, we can usually reuse the coupler and… with luck… the nozzle.

As for the smoke charge, the smoke dispersed nicely just before launch, but given the bright sun in the blue sky above, a trail wasn’t evident.  At least, I didn’t see it?  Larry said the smoke trail was visible all the way up to apogee where the smoke stopped.

If the throat maintained its shape, the performance (apogee and downrange distance) might have been quite good.  I think my initial search area was too close.  I’ll refine the flight calculations and see where might be a better place to renew the search.

Thanks to Dave Crisalli who was our pyro-op for the June 4th launch.
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I’ll update this post with the “after” photos when the rocket is found.

Launch at the MTA, June 4

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We held another successful launch event at the MTA on June 4, 2016.  Many thanks to Dave Crisalli being our pyro-op for the event.  11 alpha’s were launched.  10 by the students of Hermosa Junior High and one by Osvaldo and I.  A good time was had by all despite the serious heat of that day.   I’ll post a few photos later.

The regular monthly meeting of the RRS is to take place this Friday, June 10, 2016, at Gardena.  Hope to see everyone there.

May 2016 meeting

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The RRS monthly meeting was held at Gardena Community Center on the usual 2nd Friday of the month, May 13, 2016 (7:30pm).  As I wasn’t able to attend, I have posted some of the highlights I got from other members and attendees.  Thanks for your feedback!

Discussion continues about replacing the MTA blockhouse and upgrading the MTA outhouse.  Options are being evaluated.

At the meeting, Osvaldo showed his recycled alpha nozzle that he fitted with a graphite insert.  I wouldn’t mind having one of those?   I still have a supply of the graphite stock we received from Electro-Tech Machining in Long Beach.

We hope to have new alpha parts made soon to complete the alpha builds we need for Hermosa and have a new supply of parts for other members.  Our sincere thanks goes to American Precision Technology in San Fernando, California, 91340.

10 alphas will be built by the next group from Hermosa Junior High with recycled parts.

On the subject of alpha builds, I noticed that the fins welded to my tubes on the last two alpha builds had a lot of heat distortion even with a jig fixture.  I will try a thicker gauge (1/16″) sheet steel on subsequent builds and of course use short minimal passes to get only the attachment strength necessary.

The RRS has three new members to whom we say “Welcome!”  Richard Garcia is back in California after a stint at Firefly.  We’re glad to have him back.  As our ranks increase, we can start to build committees to assign new projects and bring ideas to completion.

Richard Garcia brought up the idea of building a basic static liquid motor with “safe” propellants to be used as a teaching tool to complement our current classes.

John Mariano expressed the need for printed educational materials to keep the RRS outreach program moving forward.  Flyers in particular would be helpful in promoting classes and rocket building events.  Written literature is always handy.  I am still working on the Alpha build curriculum and should have something to give to Chris, John and Frank for their input.  (I hope to get that out. I know we need something soon.)

It was suggested to build an amateur rocketry exhibit to have at a local museum.  Such an exhibit would be a great benefit to bringing in new members.   The RRS has a long and rich history to share.

Niels Anderson, an RRS member, put forth the idea that the RRS ought to rent a storage space to safely consolidate RRS documents which now reside in the homes of different members.

I understand that there will not be a launch scheduled at the MTA at the usual 3rd Saturday, May 21st.

There will be a launch at the MTA on June 4th.  The RRS will help the next group from Hermosa Junior High launch their Alphas.  I will also try to get my own Alpha rocket ready for the 4th of June.

The next RRS meeting is scheduled for June 10, 2016, at Gardena.