lunar’clips 2009please volunteer at a launch or at the clubs upcoming events. helping out at a...

LUNAR’clips 2009 Volume 16, Number 1

Livermore Unit of the National Association of Rocketry January-February 2009

Copyright © 2009 by LUNAR, All rights reserved.

Upcoming LUNAR Launches: Snow Ranch and NASA Ames

• March 7th, 09:00 to 16:00, high power launch at Snow Ranch. Crayon Rockets!

• March 21st, 09:00 to 13:00 regular sport launch at NASA Ames, Mountain View.

• April 4th, 09:00 to 16:00, high power launch at Snow Ranch. Interceptors!

• April 18th, 09:00 to 13:00 regular sport launch at NASA Ames, Mountain View. We will have a contest, with events for Open Spot Landing, A-motor Streamer Duration, and Predicted Duration.

As always, check the LUNAR website (http://www.lunar.org) for updated launch information. Driving directions to Snow Ranch and NASA Ames launch sites are available on the LUNAR website.

Next LUNAR Club Meeting: Model Rocket Competition

The next LUNAR Club Meeting will be held Thursday, March 19th, 7:30 PM. The March LUNAR meeting will include a presentation by Jack Hagerty and Tom Desmarais on NAR Contests. Tom will talk about the events, contest types, the "Pink Book", and the April and September LUNAR competitions. Jack will delve into the details of the scale events as well as the Nationals, NARAM. Meetings are held in Community Room B of the Livermore Public Library, 1188 South Livermore Avenue, Livermore, CA. See the LUNAR website for detailed driving directions.

Upcoming LUNAR Launches ......................................... 1 Next Club Meeting: Model Rocket Competition............ 1 July 2009: 40th Anniversary of Apollo 11 ...................... 2 Range Head ..................................................................... 3 LUNAR Club Meeting Report ........................................ 3 LUNAR BoD Meeting Report......................................... 4 LUNAR Launch Reports................................................. 5 Krystal – Booster Parachute Recovery............................ 8 Who we are...................................................................... 11 LUNAR Calendar............................................................ 12

In This Issue

Interceptors! April 4 th at Snow Ranch! Bring your Interceptors to the April Snow Ranch launch! Several of your fellow LUNAR members have been busy building Interceptors over the recent months, and it is time to let them take to the air. Festivities include a group picture of everyone with their Interceptor, and of course watching them all fly. April is just around the corner, so no more excuses, the time has come to finish your kit and fly it.

NAR Contest! April 18th at NASA Ames Join the fun! Events include Open Spot Landing, A-motor Streamer Duration, and Predicted Duration.

July 18, 2009 - LUNAR special launch at NASA/Ames celebrating the 40 th Anniversary of Apollo 11

• Enter our T-Shirt design contest! See page 2 for details.

• Please bring any and all of your scale model rockets to the July 18th launch at NASA Ames and join in the festivities. There is plenty of time to build that Redstone, Atlas, Gemini or perhaps a Saturn V that you always wanted to. Don’t have one? See page 2 for description of some commercially available Saturn V kits.

2009 LUNAR Board of Directors Our club’s BoD for 2009 - See page 4.

News and photos from LUNAR launches: January 3, Snow Ranch; January 17, NASA Ames; February 7, Snow Ranch; February 21, NASA Ames. Starting on page 5.

Krystal – Booster Parachute Recovery Two stage rocket design and construction by Alan Marcum, the excitement starts on page 8.

In This Issue




2009 is the 40th anniversary of Apollo 11, the first manned lunar landing. LUNAR is planning a commemorative launch: July 18, 2008, at Moffett Field in Mountain View. LUNARtic Alan Marcum, [email protected], is coordinating the celebratory activities.

Apollo 11 Anniversary T-shirt Design Contest You've heard about the event. Now, be the person who designs the t-shirt! LUNAR is sponsoring a contest to design the Club's Apollo 11 40th anniversary launch celebration official t-shirt. Imagine the fame, the glory, the adoring crowds thronging around to get your autograph! Okay: let's get real: imagine getting your free t-shirt and your Gold Card for a future launch--and the thrill of knowing everyone is wearing YOUR design! Here are the rules.

• Must be a LUNAR member to enter. • One design per person. • Design should reflect the celebration of the 40th

anniversary of Apollo 11's flight. • The size and content of the design must be suitable for

children, teens, and adults. • The design should not assume any particular

background color from the shirt. • Maximum of four colors used in the design. • Judges and their immediate family members are

ineligible. • Judges' decision is final. • Winner to receive a T-shirt of his or her chosen size, a

Gold Card for a future launch, and the glory of the victory.

• Entries must be received by May 3, 2009, 23:59:59 PDT. Please include your name, phone number, mailing address, and email address (if you have one) with your entry. Receipt of entries will be acknowledged.

Send your entry to LUNAR's Apollo 11 Anniversary Chair, Alan Marcum, online to [email protected], or by post to 3097 Stelling Court, Palo Alto 94303.

Where Can I Get A Saturn V Kit? What? You don’t have a scale model of a Saturn V? Here are a few. Apogee has their top-of-the-line Saturn V kit, flies on G motors: http://www.apogeerockets.com/Saturn5.asp. Many say it's the most detailed and most challenging of the Saturn V kits available. Apogee also has a Saturn I-B kit. Dr. Zooch has numerous Saturn variants. The Dr. Zooch Saturn V flies on 18mm C motors; I don't know how readily you could adapt this to a 24mm motor mount, but you could probably stuff an 18mm D motor in. http://www.DrZooch.com/rocketgallery.htm for info. Neubauer Rockets carries what they call a "micro-scale" (1/396) kit of the Saturn V, flying on 13mm A motors (and, one could imagine, 13mm B, etc. motors). http://www.NeubauerRockets.com/store/page1.html Old Estes kits are frequently available on eBay. Hint, if you get the single-motor 24mm Estes Saturn V: either build it VERY light, or plan to fly it on an E15/E28/E30/F12 motor. The original Estes Saturn V flew on a three-motor cluster of C impulse motors--i.e., 1.5x a D motor. A D motor often produces poor flights (this based on observations, including at the LUNAR celebration 10 years ago commemorating the 30th anniversary of Apollo 11). Saturn Press (Peter Alway) has a Saturn V kit, 1/195 scale. You can order these from Balsa Machining Service, http://balsamachining.com/ Also consider Sirius Rocketry's Saturn V kit. It's a bit bigger than the Apogee kit and very impressive. Flies on I284, so not suitable for launching at Ames. http://www.siriusrocketry.com Sheri’s Hot Rockets has 1/48 Saturn V, Saturn 1B, Gemini-Titan, Mercury Redstone, Mercury Atlas, and more. http://www.cjsaviation.com/ The biggest production Saturn V kit is from Polecat Aerospace, a 1/38 scale: 10” diameter, 10 feet tall, flies on five high power motors, flying this monster requires level 2 or level 3 certification. http://www.polecataerospace.com

And do not forget the Quest Micro Maxx Saturn V. Approximately 1/800 scale, we recommend flying this on MMX-II motors. Also, improve the stability: add some fin area with small tabs of (mylar) package tape. http://questaerospace.com

Apollo 11, Forty Years Later: Commemorative Launch July 18, 2009 Alan Marcum, LUNAR #392, NAR #63357




First, I want to thank everyone who railroaded, correction, believed that I would make a good President for the club. My only concern at this point is keeping up with the daily flood of email. We have held two launches with a third rapidly approaching since I have taken over as President. The January launch at NASA Ames brought out 278 rocket enthusiasts. In addition to the usual club members, we had 2 TARC teams, and about 20 Cub Scouts participating. There were several families who read an article in the “Bay Area Parenting” magazine who also came to see what rocketry is all about. The size of the crowd did draw the attention of the Air Traffic Control (ATC) personnel and I did have to go and explain to the Airfield manager that everyone stayed in the area and didn’t wonder off. This brings up safety. Ames is an active airfield and aircraft are occasionally moving around both on the ground and in the air. We need to stay in the immediate area of the range head and not wander off. Remember, this is for your safety. The second issue at the January launch was the use of the restroom inside B158. LUNAR will be providing a Port-a-potty at all future Ames launches to eliminate the traffic into B158. The Port-a-potty will be located in the gravel parking lot outside the airfield access gate. The February Snow Ranch launch was held as planned, between weather fronts. Hats off to Bill Orvis, who is familiar with the weather patterns at the Ranch, and indicated that we would be okay. In a single word, the day was perfect. I won’t bore you with the details, but 99% of the rockets landed in the punch bowl. Richard Hagen got the honors of walking the furthest to retrieve his rocket, which landed just over the nearest hill to the north after a flight to 8000+ feet. I would like to stress to everyone that we are guests and Snow Ranch and NASA Ames. Please help keep us flying in both locations by be respectful of the property, responsible your actions, and leave no trace. Please volunteer at a launch or at the clubs upcoming events. Helping out at a launch is easy and fun. The more help the club gets, the better we can help you fly! LUNAR has two big public outreach events in the next 6 months: Maker Faire, and the 40th Anniversary for the Apollo 11 lunar landing. At Maker Faire you can help others build and fly a model rocket, and also see all of the other interesting activities. LUNAR’s booth will be co-located with AeroPac’s booth again this year and this also provides a good opportunity to talk with fellow rocketeers as well. The 40th anniversary of the lunar landing is scheduled for

the July sport launch on July 18th. This is still in the early planning stages and will be coordinated with the NASA Ames celebration. If you are interested in helping with these events, please let me know and I will direct you to the right club members coordinating the event. Thanks, and see you at the next launch!

Minutes from the January 15, 2009 Club Meeting The annual LUNAR officer elections were held. There were two changes made this year in the LUNAR Board of Directors positions, otherwise BoD seats remained the same. The results of the elections are: President: Craig Saunders was not able to continue in his role as president due to his health. Tony Cooper, along with Jack Hagerty, have been filling in for Craig in his absence for the last few months. David Raimondi was nominated for the position and was unanimously voted in. No one else was nominated to run against Dave. Congratulations to our new president Dave. Vice President: Tony Cooper continues as vice president, uncontested. Secretary: David Cummings continues as secretary, uncontested. Treasurer: Sheryl Cooper continues as treasurer, uncontested. Members at Large: Alan Thym was very interested in serving his club and he was nominated for one of the MAL positions. Charlie Wittman, a current MAL, was also nominated for one of the MAL positions. With those two nominations the current MAL, Rob Tashjian, generously stepped out of the elections to give his position to Alan. Both Alan and Charlie were voted in. Congratulations Alan on your new position. The position of Past President can only go to a former club president. With Craig unable to fill this position, Jack Hagerty volunteered to continue in this position. Volunteers: Rob Tashjian continues as Cal Pyro III coordinator. Tom Desmarais continues as Contest Director. Cliff Sojourner continues as Newsletter Editor. And most crucially, Bill Orvis continues as Equipment Manager. The guest speaker for this meeting was club member Gene Engelgau who gave a very good talk about packing parachutes. He gave some good tips on folding and packing parachutes and demonstrated his techniques on a few different parachutes. We

LUNAR Club Meeting Report Dave Cummings, Secretary, LUNAR #450, NAR #78453

Range Head David Raimondi, President, LUNAR #1221, NAR #82676




all pack our own parachutes of our own rockets but it's good to see how others do the same and share their techniques and hopefully we can pick up a good tip or two. Gene demonstrated the following: 1. Fold and pack small chute and rocket (my sons Big Daddy) 2. Pack and load small diameter L1/L2 rocket chutes (2.6” Eve

with a 42” chute) 3. Using deployment bags and dual chutes. Thanks Gene for showing us your parachute packing techniques. Other topics of the evening were the following:

• The club will have an auction in April at the Snow Ranch launch.

• Alan Marcum and Dave Raimondi are meeting with NASA/Ames to discuss events/activities for the Apollo 11 Anniversary celebration in July.

• Contest director Tom Desmarais is planning a couple model rocket contests for this year. Tentative plans are for one in April and one in September with three events each.

• LUNAR Board of Directors will continue to do a pre-approval of L & M flights at Snow Ranch. Requests for these flights need to be made at least one week in advance.

• Maker Faire will be held in the last weekend of May (May 30th & 31st)

Minutes from the February 19, 2009 Board of Director’s Meeting Board of Directors Attendance: PRESIDENT: David Raimondi present VICE PRESIDENT: Tony Cooper present PAST PRESIDENT: Jack Hagerty present SECRETARY: David Cummings absent TREASURER: Sheryl Cooper present MEMBER AT LARGE: Alan Thym absent MEMBER AT LARGE: Charlie Wittman present

1. Help was needed to haul the trailer to the launches and back. Alan Thym, Dave Cummings, Tony Cooper, and Rob Tashijian have volunteered to help with this task.

2. The flight cards at the launches will be restructured. It was: $0.25 for low power cards (A thru E), $0.50 for mid power cards (F & G), and $1.00 for high power cards (H and above). It will now be $0.25 for low/mid

power cards (A thru G) and $1.00 for high power cards (H and above).

3. A port-a-potty was needed for the NASA/Ames launches. This has already been arranged and the port-a-potty was delivered for the launch the following weekend.

4. Crowd control at the NASA/Ames and Snow Ranch launches have become a concern. At the NASA/Ames launches people will not be admitted to the airfield without signing in. This will be after they have been given the chance to read the hold harmless waiver and safety speech. The LCO will read the safety procedures every hour or during a lull in the flights. At the Snow Ranch launches there will be a flyers meeting at the start of the launch and at 1:00 pm just before the Piñata rocket.

5. The treasurer, Sheryl, reported that the club has about $5,000 in the bank and that the club is in good shape. Maker Faire will be the biggest cost on the horizon for the rocket kits. Motors are already paid for. Sheryl wrote a check to Cliff Sojourner for the motors he purchased for the Maker Faire. Tony Cooper purchased new speakers for the PA system and these were tested at Ames launch on 2/21 and they worked great. Total cost for the speakers was about $60.

6. A discussion was brought up about charging for home delivery of the LUNAR Clips newsletter. From this discussion it was decided to divide the membership levels from two to three categories: • Regular Membership - $25/year. Newsletter not

included but it can be obtained via the internet. • Regular Membership Plus - $35/year. Includes a

paper copy of the newsletter mailed to homes. • Contributing Member - $45/year. No flight card

fees and the option of receiving a paper copy of the newsletter.

50 copies of the newsletter will be printed as needed for events and passing out at launches.

7. Cliff Sojourner is organizing things for the Maker Faire. Charlie Wittman has volunteered to help Cliff organize and coordinate the Maker Faire activities and volunteers. A call for volunteers will go out shortly to the General email list. 425 Quest kits will be ordered shortly.

8. Alan Marcum, who is organizing activities for the 40th anniversary of Apollo 11 celebration, talked about the T-shirt contest for this event. This will be announced in the next newsletter.

9. The possibility exists for LUNAR to participate in the USS Hornet's celebration of the Apollo 11 splashdown. Details are still in work and will be discussed in a future meeting.

LUNAR BoD Meeting Report Dave Cummings, Secretary, LUNAR #450, NAR #78453




Editor’s note: many folks post photos to the picture gallery. You can find the gallery by clicking “Gallery” on the left side of the LUNAR website main page (http://www.lunar.org), or directly from http://lunar.mtrad.com/gallery. Some of my favorites are printed here, but many more are available online – maybe even a picture of your rocket. Or maybe you could post a picture of someone’s rocket?

LUNAR Summary Launch Statistics for 2008 Here are the summary statistics for LUNAR regular launches in 2008. This includes special TARC launches, but does not include the 500 launches at Maker Faire, or any of the other outreach activities.

January 3, Snow Ranch Low ceiling from fog and biting cold kept the HPR rockets on the ground until after 1PM. LPR and MPR rockets launched steadily all day. Photos this page: log fire by Rick Baldridge, others Kevin Sato.

Statistics: 66 fliers signed in; 157 total flights, 179 motors consumed; total impulse 11049 Newton-Seconds, equivalent to a low N motor. CATO of the month: The E9 in Bill Orvis’s Mean Machine, which had a video camera on top, looking down. Kevin Sato took the matching pad shot:

Launch Reports Statistics by Jack Hagerty, LUNAR #2, NAR #55105

LUNAR Summary, 2008 Total Flights: 1709 Motors consumed, Total: 1891 Total Impulse expended: 148,877 (A high range "Q")Average Impulse Per motor: 79.3 (A full "F")

Per flight: 87.8 (A low range "G")New Fliers: 60 Total Fliers: 700 TARC Flights: 32 L1 Certs: 6 L2 Certs: 3 L3 Certs: 0

Safety Stats Category Total % of Total Total Flights: 1709 100.0

Successful: 1592 93.2 Motor Failure: 13 0.8

Unstable: 25 1.5 Recovery Failure: 79 4.6




January 17, NASA Ames From LUNAR President David Raimondi:

LUNAR had a great launch today. We had abundant sunshine, little or no wind, and a huge crowd of people! In attendance were ~20 Boy Scouts, 10 Four H members, and 1 TARC team. The grand total for the day was 278 people who came out to fly or see what rocket launching was all about. We had 251 flights. Everyone was very helpful, especially the Boy Scouts and 4H kids who each carried a stanchion all the way across the ramp area, and help with set up. We still had plenty of people who stayed to the end to help with clean up and the FOD walk-down.

A few more statistics: in the large crowd we hosted 65 first-time fliers! In the 251 flights, 266 motors consumed; total impulse: 2796 Newton-seconds, which is a low range L.

The 3-way Crayon Rocket drag race was a crowd pleaser. George Thym clearly won first-off-the-pad with a G53 Fast Jack motor, Alan Thym went faster with G76 Mojave Green, and Cliff Sojourner brought up the rear with a plain old G64 White Lightning.

Photos this page by Paige K Parsons.




February 7, Snow Ranch Statistics: 166 total flights, 176 motors consumed; Total impulse is 17165 Newton-Seconds, a mid-range N. We had 24 HPR flights, with 11 H motor, 9 I motor, and 4 J motor flights. 92 total fliers, 2 new fliers, and 2 L1 certifications noted. Photo by Dave Flournoy:

Photos by Rick Baldridge:

February 21, NASA Ames After the boomtown that was January at Ames, our February launch seemed quieter: at 197 total flights, 211 motors total, about 80% of January’s flight volume. But, the total impulse of 3758 Newton-seconds (still a low L) was quite a bit higher (by 30%) than January. This is likely accounted for by the 11 F and 12 G motor flights. Photos this side by Paige K Parsons:




Motivation and Inspiration Though some of my favorite rockets are simple 3FNC or 4FNC designs —Alpha 3 and Big Bertha are good examples—I really prefer something a bit less mundane: transitions, oddball stability or recovery systems, things that make the rocket both visually and dynamically interesting. That includes multi-stage rockets. I’ve had a perfect record flying 2-stage rockets using direct staging (i.e., taping the booster and sustainer motors together): 100% failure, dating back over forty years (I’m a BAR—Born Again Rocketeer).

Despite that record, or perhaps because of it, multi-stage rockets intrigue me, and I decided to try yet again. Only this time, I wasn’t going to use direct staging: I’d use “indirect” or “gap” staging, with some space between the two motors and holes to vent the inter-motor pressure. All the multi-stage boosters that use black powered motors that I’ve seen use tumble recovery: after ignition of the second stage motor, they simply tumble back to the ground. I didn’t want to use tumble recovery on the booster, for two reasons. Since I was using indirect staging, I planned to build a longer booster than I was comfortable having come tumbling down from about 50 meters in the air. Though it was likely that the booster would flutter, I wasn’t comfortable with the possibility of the booster going ballistic after separation, and even if it fluttered, something that big could still hit pretty hard. Beyond this, the concrete ramp at Moffett is unforgiving and harsh on hard-landing models; I didn’t want to count on the booster landing in the grass. The question of recovery methods and deployment then had to be addressed: the interesting bits of this design.

The Design I had in mind a relatively large booster: BT-60 or BT-80, 4 or 6 cm diameter, respectively, and 20-30 cm long. With this long a booster, the fins for the sustainer would be comparatively far forward, so the booster fins would have to be large enough to compensate—and I started thinking

about parachute recovery, given the mass of this stage. Where, though, to store the parachutes, and how to get them deployed? I didn’t want to use electronics and a separate ejection charge to deploy the booster parachute: I wanted to use black powder motors and no on-board electronics. I thought about a parachute stowed around the (long) motor mount tube. To deploy the chute, I thought about attaching it to the sustainer in some way—a string, for the sake of discussion—and having that string be detachable so the sustainer wouldn’t just keep pulling the booster along behind it. I’d have to protect the booster’s parachute somehow from the sustainer motor’s flame (a Kevlar heat shield on top of the parachute, for example). The simple deployment mechanism seemed like a challenging engineering problem. After some thought, I didn’t see a way to have that string detach in just the right way, at just the right time, dependably, and I didn’t want to trust to the chute just spilling out on its own. After a bit more thinking, I came to clustering in the booster. I had all the thrust I’d need—even with a BT-80 booster, an Estes D12 should be more than adequate—but I needed an ejection charge. With the main booster motor igniting the sustainer, no ejection charge would be available from it. But, if I added another motor, I could use its ejection charge to deploy a parachute. I decided to use two small parachutes each deployed by a 13mm motor, with clustered ignition on the ground. I didn’t care about the thrust from these “auxiliary” motors, only about the delay and ejection charges. My first thoughts on locating the chutes was to use a classic in-line clustering configuration, with the 13mm (BT-5) motor mount tubes inside the rocket body flanking a 24mm main

Booster fins and motor mount (yes, TTW is overkill).

Krystal on the pad.

Krystal – Booster Parachute Recovery Alan Marcum, LUNAR #392, NAR #63357




motor mount. A BT-80 tube is large enough for this, so this was a possibility. I didn’t come up with any ways to get the parachutes out of the rocket, though. I considered rear ejection: though there would be space in the BT-80 for another pair of 13mm tubes, or even 18mm (BT-20) tubes, I didn’t like the idea of having to duct the ejection charges from the motor mount tubes into separate parachute tubes. I considered somehow having the tops of the interior tubes stick out through the booster body, or poke out the side, perhaps canting the tubes, topping each with a nose cone and carefully fairing the whole thing to avoid creating an air scoop, but that seemed fraught with problems. That left attaching things to the outside. What about exterior pods? That was the answer! Exterior pods would be easy to build. It wouldn’t be hard to simulate with RockSim, even before the latest version, RockSim 9, was introduced: hand-editing the XML rocket definition file is straightforward, and Tim Van Milligan had various articles

describing what to do in his regular newsletters. The only real difficulty was tricking RockSim 8 into adding nose cones to the pods, since RockSim 8 only allowed one nose cone per rocket: I used an appropriately shaped transition with a near-zero forward diameter. (This isn’t a problem with RockSim 9: it supports external pods, including the nose cone.) The rocket wasn’t complete without a sustainer. It’s very easy to punch through our 1000’ (300 meters) Moffett ceiling with a two-stage rocket. (Simulations with Krystal show that staging a

D12 to a D12, for example, would top 450 meters, nearly 1500’.) Besides, I like to see what’s going on with my rockets, especially newer ones. I decided to keep things complicated and build an 18mm motor mount into the sustainer, planning to fly the first launch on a D12 to an A8. I’d settled on BT-80 for the booster; I had a nice nose cone for a BT-60 in my parts bin, I had some BT-60 tubes, and I even had a transition between BT-80 and BT-60, so I went with that. I needed to bore a hole through the center of the transition, ideally one that would taper from about 24mm to about 18mm (plus a little on the small end, for the engine hook). Lacking a drill press, milling machine, or lathe, I got a bit of help on this from my father, whom I happened to visit (on the east coast) just as I needed to bore the

hole. His drill press and some creative use of hole saws, a nibbler, and rat-tail files took care of the hole. The final interesting aspect was the vent holes needed for indirect staging to be successful. I located those near the top of the transition: four holes, 90° apart, each hole about ⅛” (3mm) in diameter. Mostly for aesthetics, I faired these vent holes using two small vacu-formed plastic nose cones (also in my parts bin), each carefully cut in half.

One snag arose during the late stages of building the rocket: a little interference between the pod nose cones and the booster body tube. I anticipated this possibility, though: I had carefully test-fit things at each step before applying glue, and discovered the problem before actually gluing anything down. It was simple enough to cut a pair of thin balsa strips for stand-offs. Add a little paint, the parachutes, and a heat shield, and we were ready to fly.

The Flights The weather forecasts for our January launch window were beyond promising: sunny, minimal winds, mild temperatures, a perfect day for launching. I finished building and painting Krystal on Thursday evening, having ensured earlier in the week that I had all the needed motors: a D12-0 for the main booster motor, two ½A3-2Ts for the aux motors, and an A8-3 for the sustainer. On Friday, I

The interstage

Pods with stand-offs

Launch photo by Paige K. Parsons




built a clip whip for a three-engine cluster to make it easier to connect all those igniter leads. Preparing the rocket for flight is straightforward: A8-3 in the sustainer, the D12-0 in the central booster motor tube, and the two ½A3-2Ts in the pods; dog barf in the pods, then the 30cm plastic parachutes and the pod nose cones; a Kevlar parachute protector and 45cm parachute in the sustainer. I triple-checked the igniter leads to ensure nothing was shorted. I asked for one of the mid-power pads: I wanted the extra current from that 1 farad capacitor (to really ensure ignition), I wanted more distance from the range head (for safety, in case the staging failed), and I wanted to be close to the grass (so that, maybe, the two stages would land there). At the pad, the three-way clip whip made the hook-up as easy as I’d hoped. Again, I triple-checked for shorts, and waited. When Tony pushed the LAUNCH button, the D12 lit immediately, and the rocket launched. I couldn’t tell whether the aux motors had lit. (Each had so little thrust that the flight would have been straight even if one of the aux motors had lit and one had not. If only the two aux motors had lit, but not the D12, the rocket wouldn’t have moved very far!). The sustainer lit about 1¾ seconds later; shortly thereafter, I saw two booster parachutes open! Success: all four motors lit! The booster didn’t quite make the grass (and a fin tip was dinged); the sustainer did, though. I thought about quitting while I was ahead, but I also wanted to ensure that this flight wasn’t a fluke. I did a very quick-and-dirty repair job on a zipper (one of the pod tubes; more on this below), prepared the rocket, and had another successful flight with all four motors lighting as planned. At last, my perfect record with two-stage rockets was destroyed.

Challenges, Changes I mentioned a zipper in one of the pods: this was caused by early

deployment of the parachutes. It’s not that the delay charge was flawed, it’s that a two second delay was too short. The challenge in selecting that delay period, though, is in determining just how fast the booster will be going at aux motor ejection. How fast will it slow down following separation? In retrospect, the interstage transition improved the aerodynamics of the booster enough that it took longer to slow than I anticipated. It’s also difficult to get the needed information from RockSim: possible but difficult. Determining the projected altitude of the sustainer had its challenges, too. If I simply used ½A3-2Ts as the aux motors, the sustainer didn’t light until two seconds after the D12 burned out. I ended up creating a fake motor for the aux pods with a near-zero delay, which then led RockSim to ignite the sustainer at booster burnout. I made the pods out of BT-20, which proved a little small for the parachutes I really wanted. I’d have preferred 45cm nylon chutes with Kevlar chute protectors, but the BT-20 was big enough only for 30cm plastic chutes with dog barf. What’s next? I’m already designing a successor (to soak up my spare time when I’m not working on my Saturn V…).




Who you gonna call? LUNAR HOTLINE (925) 443-8705 PRESIDENT David Raimondi, [email protected] (408) 997-2571 VICE PRESIDENT Tony Cooper, [email protected] (510) 471-3648 SECRETARY David Cummings, [email protected] TREASURER Sheryl Cooper, [email protected] MEMBERS AT LARGE Alan Thym, [email protected] Charlie Wittman, [email protected] EQUIPMENT Bill Orvis, [email protected] MEMBERSHIP Tony Cooper, [email protected] NEWSLETTER Cliff Sojourner, [email protected] CAL PYRO III Rob Tashjian, [email protected] CONTEST DIRECTOR Tom Desmarais, [email protected]

=========================================

Who We Are...

LUNAR is the Livermore Unit of the National Association of Rocketry, Section #534

LUNAR is located in Livermore, California, about fifty miles southeast of San Francisco. We are organized to supply a safe, educational and legal means of furthering the hobby of model and high-powered rocketry in northern California, to aid and encourage the development of all club members’ knowledge and expertise in the area of rocketry, to promote youth education and community involvement, and to engage in scientific, educational and related activities. LUNAR is open to rocketry hobbyists of all ages to further the sport and science of hobby rocketry within the NAR (National Association of Rocketry) and Tripoli safety codes. These codes have allowed hundreds of millions of model rocket launches by hobbyists since the late 1950s without serious injuries.

LUNAR also supports assorted rocketry activities of community youth groups. We have hosted launches (and in some case building sessions) for the Boy Scouts, Girl Scouts, 4H, YMCA Adventure Guides, the GATE program, and LARPD Science Camp.

Launches

Section launches are usually held from 9:00 a.m. to 1:00 p.m. on the third Saturday of the month. Generally these are sport launches, although we occasionally hold sanctioned contest

launches for points in the NAR national contest standings, theme launches where we focus on a particular class of rocket, and night launches.

LUNAR’s Snow Ranch launch site accommodates all rockets from 1/4-A to M motors, with a 15,000 foot maximum altitude. The LUNAR Board requests notification of L and M flights a week before the launch date. Contact the LUNAR Members At Large directly, or post a message on [email protected].

The LUNAR Hotline - (925) 443-8705

The Hotline is available to provide up-to-date event information. It’s a good idea to call our Hotline to verify the date of the next launch or meeting.

On launch days, the Hotline recording is updated by 7:00 AM to reflect the Go/No-Go status of the launch. On launch days with questionable weather, it is especially important to call the Hotline to get the latest information. You can also leave messages on the Hotline.

Meetings

Section meetings are held bi-monthly. These meetings cover general section business, and typically include presentations by club members or other experts on some aspect of the hobby, ranging from simple building tips to advanced science and engineering principles. Officers’ meetings are held bi-monthly, alternate months from the section meetings, and typically concern administrative details.

The LUNAR annual meeting is held during the first quarter of the calendar year at a time and place announced to the membership. At this meeting, officers are elected and other club business is conducted.

World Wide Web site!

LUNAR maintains a Web site at http://www.lunar.org

You will find a lot of stuff to see on the web site, and it always has the latest information about LUNAR and our activities. For example, you’ll find our latest launch and meeting calendar, directions to our launch site, a gallery of photos from past launches, the on-line issues of the LUNAR’clips (the section newsletter), our section bylaws, pointers to member rocket pages, pointers to other rocket and space related information on the Internet, … and lots more!

Membership

Your membership fees support the costs of launch operations, equipment maintenance, meetings, newsletter, outreach events, and other public services. Join LUNAR now! Yearly fees: Youth (to age 11) is $6; Junior (ages 12-17) is $6; Adult (over 18) is $25. Become a Contributing Member for an extra $20 ($26 Youth & Junior; $45 Adult), and your flight cards are free.

2009 LUNAR Calendar Launches at Snow Ranch or NASA/Ames Moffett Field (see website www.lunar.org for directions)

Meetings at Livermore Public Library, Community Room B, 1188 South Livermore Avenue, in Livermore. WARNING! Times and dates are subject to change with little notice. Setup starts an hour before the listed time and teardown and packing up usually takes an hour after the listed time. For launch confirmation call the LUNAR Hotline (925) 443-8705 after 7 AM on launch day. Visit the LUNAR web site at www.lunar.org for the latest information.

January

Jan 3, 9am: Snow Ranch Launch Jan 15, 7:30pm: Club Meeting: Elections Jan 17: Low Power Launch, Moffett/Ames

February Feb 7, 9am: Snow Ranch Launch Feb 19, 7pm: Board of Directors Meeting Feb 21: Low Power Launch, Moffett/Ames

March Mar 7, 9am: Snow Ranch Launch Mar 19, 7:30pm: Club Meeting: Model Rocket Competition Mar 21: Low Power Launch, Moffett/Ames

April Apr 4, 9am: Snow Ranch Launch & Auction Interceptors Apr 16, 7pm: Board of Directors Meeting Apr 18: Low Power Launch, Moffett/Ames: Contest: OSL, A-SD, PD

May May 2, 9am: Snow Ranch Launch May 16: Low Power Launch, Moffett/Ames

May 21, 7:30pm: Club Meeting: Mark Annis, Space Shuttle

June Jun 18, 7pm: Board of Directors Meeting Jun 20, 9am: Low Power Launch, Moffett/Ames

July Jul 16, 7:30pm: Club Meeting: topic TBD Jul 18, 9am: Special Low Power Launch at Moffett/Ames: 40th Anniversary of Apollo 11

August Aug 15: Low Power Launch, Moffett/Ames

Aug 20, 7pm: Board of Directors Meeting

September Sep 17, 7:30pm: Club Meeting: Quest Force 5 Kitbash Build Session Sep 19: Low Power Launch, Moffett/Ames Contest: STA, A HD, 1/4A FW

October Oct 15, 7pm: Board of Directors Meeting Oct 17: Low Power Launch, Moffett/Ames

November Nov 7, 9am: Snow Ranch Launch Nov 19, 7:30pm: Club Meeting: topic TBD Nov 21: Low Power Launch, Moffett/Ames

December Dec 5, 9am: Snow Ranch Launch Dec 17, 7pm: Board of Directors Meeting Dec 19: Low Power Launch, Moffett/Ames

LUNAR c/o Membership Chair 31120 Chicoine Ave. Hayward, CA 94544-7432

lunar’clips 2009please volunteer at a launch or at the clubs upcoming events. helping out at a...

Documents