Saturday, February 28, 2009

Astronauts and missiles

I had the opportunity on Wednesday to attend a talk given by Captain Steve Bowen, NASA astronaut (STS-126) and the first submariner in space, at the Submarine Force Library and Museum in Groton, CT. He gave an interesting talk on his mission; of particular note was a slide show of the Shuttle / ISS docking sequence. Afterwards, I was able to shake his hand and get his autograph.

He's the second astronaut I've met; the other was Captain Dan Burbank. Capt. Burbank works at the US Coast Guard Academy where I've participated in math competitions; during one I had the opportunity to meet him. He's been on two missions - STS106 and STS115 - and he's in the astronaut band Max Q.

Outside the museum are 4 subs, including a Japanese mini-sub and a SEALs transport sub, and two missiles.

The one in front of the museum is ironically a French Exocet ship-to-ship missile; US subs may be able to carry and use them, though that's probably classified. Los Angeles-class subs can definitely carry similar Harpoon ship-to-ship missiles; though. It'd make a good scale model subject; you're free to use that image for scale data.

The other is a Polaris A3 sub-launched ballistic missile; George Washington-class subs could carry 16 of them. I think a GBU-24 Paveway III kit would make a good base for a scale model of it; obviously it'd require clear plastic fins of carefully balanced canted motors to spin-stabilize it.

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Launch Report #23

I launched 2 MMX rockets in the dark today... they flew fine, but both flew off into the dark grey yonder. I'll find em tomorrow.

First was the Hummingbird on its first flight since October. The two fins I added helped it fly straighter than before, but it ejected about 60 feet up and 40 away, and I never saw either part come down even with all the outside lights on. I found the pod in the street later, but the glider is in hiding.

Second was my cloned Mosquito on a MMX. It flew to 60+, ejected a bit higher, and I never saw it again. The engine pod/adapter landed on the street, but I didn't find it.

Both the main body of the Mosquito are definitely not on the street (the pod is easy to remake), so they'll be safe from cars if not the snow and rain that's a-comin'...

Still at 29.1% I, but down a bit on the flight stats, but not enough change to mention. Good night.

Orbital Transport Pictures

31 pieces of balsa, 2 nose cones, 1 tail cone, 3 tubes, 1 engine hook, 3 rings, and 2 launch lugs, plus a screw eye and shock cord.

A close-up of the hollow tail cone on the glider. I personally think it's even better looking (plus a hellofalot stronger) than the original.

The belly of the beast, showing the 'scramjet' assemblies, which required 4 pieces of balsa and 2 tubes each.

What it looks like with the glider on the booster.
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Monocopters, saucers, and the SpaceBusII

My awesome Tiny Tim/WAC Corporal scale model. It's about 13.25" long and will fly on 1/2A3-4Ts, and maybe 1/4As and full As if it's calm and visibility is good (for the As). The protrusion on the right of the WAC Corporal is the raceway, which carried electronic cables on the real thing, and would make for a prefect location for staging electronics wires on a larger staged version. Note the translucent 6mm tubing I used for the interstage section.
My 13mm and 18mm monocopters (the Whirling Dervish and the Whirling Twirling Tornado of Flame and Death and Doom) and the 13mm saucer. All can fly in my yard on full As.

The new SpaceBusII. Space bus nose cone, 19mm tube from a kitbashed Totally Tubular, a bit of 18mm tubing from the OV10, the original Space Bus fins, and the 13mm motor mount tubing. It'll fly well on 1/4As and 1/2As of all delays, plus maybe an A3-4t if I'm daring. Out of a tiny bit of superstition I'll never fly it on an A10-3T as that's what killed the original Space Bus.
Its novel recovery scheme. The 19mm tubing slides smoothly off the 18mm tubing at ejection al the two parts fall separately. The fin/motor unit is like a booster stage and tumbles, while the nose/body section is halfway stable but comes in slow and spinning.
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I painted the Mozzie today. One coat of yellow on the fin, then I masked it off, applied white as a sort of sealer for the huge balsa nose, then a thick coat of red for the rest.

After painting.
The little guy is barely bigger than the 29/24 adapter.
The adapter, made of 2 29mm centering rings, one 24mm centering ring, 1/2" of 29mm thick-wall motor tubing, and 3" of 24mm tubing.

Big and little skeeters.
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Friday, February 27, 2009

Master List of my rockets (currently)

  • Pen rocket: pretty much self-descriptive. Made from a Bic pen.
  • IT: The famous Flying Drainplug; a plastic saucer-type craft.
  • RNGbane the Valkyrie: rear-motored weight-ejection canard-delta boost-glider; needs a new canard fin.
  • Hummingbird: front-motored pop-pod boost-glider.

  • Gauchito: Short, fat, Little Joe-esque scale model of an X-prize contender. One of my older rockets.
  • Jinx: Garish purple plastic and washable; my fifth-grade teacher found it while cleaning her desk and gave it to me cause she knew I liked em. It's the only 13mm rocket that I've used as an upper stage.
  • Cohete: The bastard child of several rockets and dowels; a little stick-finned wonder.
  • 13mm Saucer: Simplest rocket ever. 1.5" of BT-5, a 13mm centering ring, and a bit of posterboard. Flies to about 60 feet on full As.
  • Whirling Dervish: My lowest and nastiest rocket. Flies to about 10 feet at 10 rps.
  • *WAC Corporal: Brand new and freshly painted. One of the only complex models I've evr built from just a plans sheet and parts list.
  • *Mosquito: A clone of the original. It'll fly mainly on MMX and 1/4A3s.
  • Rokit: the joke rocket that's a 13mm motor mount inside a D12 casing.
  • *SpaceBusII: A semi-clone of my second rocket using its nose cone and fins and featuring break-apart / tumble recovery and handdrawn graphics.

  • Cosmic Cobra: My first rocket with a autogyro nose cone and the now-gliding booster. After 7+ flights, still as good as ever.
  • Wizard: minimum diameter sport model; one of my first rockets.
  • Astrocam: the famous camera rocket. The motor mount is beat up and the camera is questionable, but it still flies.
  • Mongoose: shortened, high-flying 2-stager. One of my most-flown rockets.
  • Bullpup: my first scale model and the one that introduced me to gliding boosters. Also, its building is the source of the nasty scar on my left thumb.
  • Orbital Transport: survived one me-induced crash. I really oughta paint it one of these days.
  • SpaceshipOne: it survived its visit with the local flora with only a few missing decals (plus the chute still up there) and now it's almost ready to fly again.
  • Screaming Yellow Zonker!: my best-named and coolest-sounding rocket by far.
  • Hi: 18mm generic booster. Flown at least 6 times.
  • 18mm saucer: goes nowhere on a B6, but rocks on top of my 24mm saucer.
  • Whirling Twirling Tornado of Flame and Death and Doom: my 18mm monocopter; seriously underpowered on an A8.
  • Rama: The amazing underpowered understable widebody high-drag scale-ish monster; perfect fit for a composite D.
  • Frankenstein: a SPEV named after the Edgar Winter song, it'll fly to half a maile on a D12-0/C6-0/C6-7 load using a CHAD stage and the Vampire booster.
  • Cloud Hopper: my semi-clone up-powered Goonybird replica.
  • Pigasus: my original-design Goonybird; like the Cloud Hopper it was formerly a Baby Bertha.
  • GBU-24 Paveway III: A nice scale model I got for Christmas. It was the testbed for my homemade 12" chute.
  • Alexi Leonov: 2-staged payload-hauling Estes Loadstar.
  • Glider: generic boost pod; capable of lofting one of several gliders.
  • Astron Invader: downscaled and overpowered circular boost glider; it does rather spectacular aerobactics.
  • Transwing: big, heavy flop-wing glider. probably the best glide ratio of all my rockets.
  • Scissor-Wing Transport: Classy scissor-wing glider with decent altitude performance but a poor glide.
  • *Mach My Day: 18mm machbuster that goes faster than the bullets from that .45 Magnum.
  • Comanche-3: 3-stage longneck rocket that I'll probably never get the sustainer back from on 3 stages.
  • Vampire: red-and-black booster stage for heavy rockets, or those like Frankenstein intended to be lost.
  • 24mm saucer: my largest-diameter rocket at 13" in diameter.
  • *Mozzie: 5x MPR upscale of the classic kit. It'll fly mostly on D12s and 24mm reloads. My first 2.6" rocket.

Total:39, with all but 5 flown.

Thursday, February 26, 2009

WAC Corporal done!

It's been painted by my awesome mom... a nearly perfect 1:21.8 scale model. Black, white, and silver. I made a stand out of an old 13mm motor casing and a chunk of wood... it's now sitting on my shelf. It'll fly on 1/4A3-3Ts, 1/2A3-4Ts, and maybe full As once in a while.
Speaking of which, I'm going to get a pack of MMX, a pack of 1/4A3-3Ts, a pack of 1/2A3-4Ts, and a pack of B6-2s.

Tuesday, February 24, 2009

WAC Corporal

It's finished and flight-ready.. just needs some paint.
She's 13.25" long, .54" in diameter, and therefore roughly a 1:21.8 scale model. This guy is crazy enough to build a full-scale one though: a foot in diameter and 24'1" long. Using the data from here, I can calculate the motor types (equivalent) of the original:
Tiny Tim booster: 222kN for 0.6s = 133200 Ns, or a Q222000 (62.6% Q)(solid fuel; that much energy in that short a time period is basically a barely controlled explosion. No wonder those things made good ground-attack rockets in WWII)
WAC Corporal: 6.7kN for 47s = 314900 Ns, or an R6700 (92.2% R) (liquid-fuel; this burnt very slowly like a hybrid motor)

SpaceShipOne again!

I got the nose cone back yesterday.... the shock cord snapped at the nose cone shoulder on Sunday night and it fell down... into the middle of a briar patch. I went in and got it back though.
It'll fly again with a new shock cord... and a smaller parachute.

Monday, February 23, 2009

Orange Crate O' Death

My next project, as found on EMRR:

A D and E powered boost glider, made from an orange crate. Or in my case, a clementine crate. No idea how it'll fly, But it'd rock on an E15-4 composite.

Also, in case anyone wondered, the chemical formula for APCP (Ammonium Perchlorate Composite Propellant) is NH4ClO4, and because it decomposes below the point of melting, it releases enough oxygen, like blackpowder, to burn sans on the moon. Imagine sending a G-motor rocket into orbit.... course, there's not much you can do in the way of recovery systems...
APCP on Wikipedia

Sunday, February 22, 2009

Launch Report #22

Good weather, new motors, and some crappy results:

First came the newly repaired Gauchito on an A10-3T. It flew straight to about 200 feet, ejected the nose cone, and failed to eject the 16" chute I'd stuffed in it (just to try for duration). It came down ballistic but safe a few feet from my dad about 20' from the pad. Score so far: chutes: 0/1

Next came Rama on a C6-3. It chuffed on the pad, fully ignited off the pad and pointed 20° uprange, arced over, and ejected about 1 foot off the ground. Two fins are broken off, but amazingly that tough 3" mailing tube took no damage. It'll fly again, but only once, and on a composite D that'll get it safely OUT of here. Chutes: 0/2

Next was the OV10 on a B6-2. It launched straight and high on a B6-2, ejected around apogee, and came screaming in at about 50 feet per second. The motor tube was bent and the glider in three pieces; I didn't try to repair it, but merely took 2 pieces of the motor tube, the 4 centering rings, the engine hook, the balsa nosecone, and some good bits of balsa and put them in my parts box. RIP. Chutes 0/2; gliders 0/1.

Fourth came the Orbital Transport on a B6-4. It was underpowered and too long a delay; it reached its peak around 250 feet up and ejected about 20 feet off the ground. The glider just made it off the booster and hit undamaged but without a glide; the booster broke off one upper vertical stab and one drooped wingtip; both are now repaired. The motor mount was launched upwards out of the rocket; it landed a few seconds later unharmed. It is reglued with plenty of wood glue. Chutes 0/3; gliders 0/2.

Fifth came the Comanche-3 on a C6-0 / A8-3 combo with the C6 inside a heavy D12 casing in the 24mm stage to make it heavier and keep it on the field. The approximate sequence of events:

The C6 booster ignites and launches it smoothly off the pad. It burns for 1.7 seconds, then stages. The A8-3 ignites and sends the sustainer on its way. The C6 inside the D12-0 is popped out of the booster and falls away, reaching the ground in about 5 seconds. 3.5 seconds after ignition, the A8 ejects right around apogee at between 700 and 1000 feet. It is kicked backwards out of the rocket and falls away, lost to the grass. The nose cone snaps the knot attaches to it and falls away. the streamers fail to come out; without nose cone, motor, or deployed streamers the body is very stable and comes in ballistic. It core sample right around when the nose cone hits; it takes a 1" sample of the soft earth but is totally undamaged. About 5 seconds later, after a good 15-20 seconds, the big, light 24mm booster - sans motor casings, finally touches down. All within 150 feet of the pad. The Comanche-3 is undamaged and will fly again, maybe even on that combo. Chutes 0/3; gliders 0/2; streamers 0/1.

In total, I've flown 91 motors on 78 flights on 38 different rockets (and separate boosters) for a total of 412.42 Ns - a 28.9% I (Over a quarter of the way to a J!), equalling 4.53 per motor (81.3% B) and 5.29 per flight (5.7% C). I also updated my spreadsheet to automatically do those calculations for me.

The SpaceShipOne nose cone is still hanging in the tree, but with the nasty wind tonight maybe it'll snap free.

Goodnight, all.

Mozzie Finished!

Well, except for the paint job....

I got all three fins glued on - solid, with lots of wood glue - and the launch lugs on. They're 1/4" lugs, but I placed them far enough apart that it won't wobble too much on my 3/16" rod. I also tied on the nose cone with a double square knot and threaded the parachute and protector onto the thick nylon chock cord. It's roughly 20" tall, about 11oz unloaded, and ready for paint. It's almost exactly a 5x upscale of the original mosquito. It'll fly to about 300 feet on a D12-3 or about 450 on a D12-0 / D12-3 combo. (I've changed my TIRASP-93 to sim 2-stage rockets).

I've also repaired the 2 broken-off fins from the Orbital Transport (from a launch yesterday, report coming) and reglued its engine mount.

The Alexi Leonov has a new 18mm motor mount with one reused centering ring and one new one made from cardboard.

I've been working on a scale WAC Corporal / Tiny Tim with a 13mm motor mount from plans from the NAR guidebook. I've got the fins and body tubes cut, the motor mount assembled, a shock cord and streamer ready, and the complex interstage coupler done. It's made of 2 pieces of 13mm motor casing, 3 sections of 1/16" dowel (a toothpick), masking tape, and 6mm tube - in this case, a translucent piece from an old floss dispenser. I'd already made the balsa nosecone about 3 weeks ago.

Now on to do that launch report...

Saturday, February 21, 2009


I opened the cheap mini digital camera that will soon go in a payload bay, and it even works, but 2 things are not good:
1) The circuit board is too big for a BT-60 payload tube.... I'll need BT-70 or probably BT-80.... oh well.
2) The software installs on my computer, but the device drivers won't.... so right now I can't get any pictures off it...grrr.

Friday, February 20, 2009

Mozzie Building

I actually found some time to assemble half of it today. In roughly chronological order:
  • Tested the 18" ripstop nylon parachute. It's amazing: folds into a tiny ball, has nice thick, long shroud lines that don't tangle, unfolds perfectly in cold weather, and is a nice deep purple that will stand out against blue sky, clouds, grass, etc. Far better than Estes chutes, and not ridiculously priced if you buy it alone: $12.50 for an 18" chute and a 9" flameproof parachute protector that functionally replaces wadding.

  • Glued a heavy screw inside the hollow in the nose cone for balance; then glued the thick eye bolt and its plywood holder disk on. Solidly on. I am using wood glue throughout rather than suggested epoxy, but I have no doubt that it'll hold together.

  • Assembled the motor mount. Glued the two plywood centering rings on, then cut excess off the forward end of the mount per the instructions to make room for the recovery system. Even so, room is tight. I wish the nose cone shoulder was just a hair shorter.

  • Made a 29mm to 24mm adapter from 3" of 24mm tubing, three 24mm-29mm centering rings, and half an inch of the extra motor mount tubing. I'll get a picture up sometime. The adapter and the motor are both held in place for flight by a quick wrap of masking tape. The adapter will be perfect for motors like D12-3s and a 24/40 reload casing with reloads like D15-4s and E11-3s.

  • Attached the Kevlar shock cord to the longer nylon cord and the motor mount. It's held solidly in place, far better than an Estes-style mount. Together, there's over 6' of shock cord. I like the look of a rocket dangling far under its chute on a long shock cord; it makes the rocket look bigger. (Estes-size rockets will use about twice the body length of rubber band shock cord, while a typical L3 rocket might use 150' - ten times the body length.)

  • Glued in the motor mount, and put a fillet on the back end. I'll glue in the fins and launch lugs and attach the nose cone tomorrow; I might even fly it Sunday. Then again, it's Saturday about 5 minutes.

*Goes to bed*

Launch Report #21

I flew my new 3" diameter 13mm saucer. It went to about 50 feet on an A3-4T and ejected just above the ground. Only half the clap cap blew out, though... odd.
I'm up to 73 flights on 85 motors for 381.92 Ns (19.4% I), which is 4.49 Ns (79.6% B) per motor and 5.23 Ns (4.6% C) per flight.
More later. I'm gonna build that Mozzie now...

Wednesday, February 18, 2009

Update on Life

Computer is still kinda touchy, so I'm using my parents' desktop.
1) I cut the booster tubes for the Orbital Fatass and glued them in - now all I gotta do is glue the wings on, attach the nose cone and chute, and fly. Update at 8:15 pm: It's the wings are glued on and I moved the glider hook assembly so it'll be more stable and the glider won't flop around so much. The shock cord mount is currently gluing...
2) Repaired the motor mount on Gauchito; it'll fly soon on an A10-3T.
3) I gotta get a pack of MMX and a pack of 1/4A3-3Ts for my smaller rockets
4) Aerotech has opened their Value Rockets web store. They're trying to bring mid-power composite motors to the masses and I think it's awesome:
3-packs of D10-3/5/7s and D21-4/7s for 15.90 (18mm)
3-packs of E15-4/7/Ps and E30-4/7s for 18.90 (24mm)
18/20 RMS hardware for 29.90
24/40 RMS hardware for 34.90
24/60 RMS hardware for 39.90
18/20 reload 3-packs for 7.90
24/40: 16.90 for D, 22.90 for E, and 26.90 for F 3-packs
24/60: 19.90 for 2-packs of F reloads
Plus a complete starter set with Mantis pad (normally $115 alone), launch controller, and 29mm rockets for 99.90
5) My motor order came today. Except for the E30-4 which is out of stock and was just taken off my motor. I guess I'll just get a 3-pack instead...
6) Between the Orbital Fatass booster tubes, new motor mount for the Gauchito, the Mosquito, and a few other things, I've already used 18" of BT-5. Wow.
More later.

Tuesday, February 17, 2009


My Apogee order arrived today... yay stuff! Everything is there and umdamaged. I'm impressed with the size of the Mozzie kit. I made a real-size Mosquito out of BT-5, a thrust ring, 3 fins, a launch lug, and the BNC I already made. Glued and painted in the famous red-and-yellow livery. I also glued some on my Orbital Transport. More tomorrow morning.

Computer Problems

My laptop is currently almost nonfunctional right now; almost anything causes it to crash. So... my blogging will be a bit light till I can get it fixed. it doesn't appear to be a virus, but rather some sort of software / hardware / system problem. I'm planning on calling tech support soon so hopefully within a few days everything will be good.

Sunday, February 15, 2009

Big motors in little rockets

There seems to be a trend of taking small, fat rockets designed for small motors and sticking really big motors in them. A selection of modded Estes kits:
Patriot: 18mm to 24mm
Bullpup: 18mm to 24mm
Big Daddy: 24mm to 29mm: #1, #2, #3
Baby Bertha: 18mm to 24mm
Super Big Bertha: 24mm to 38mm
Fat Boy: 18mm to 29mm
Fat-Ass-Tron Sprint: a Fat Boy converted to use 38mm motors to push it into the transonic range
Beg Bertha: modified to use "Pitfield" motors, which were fairly large E blackpowder motors labeled as Fs. They included an F72-0 (really E15-0) booster motor.
Big Bad Bertha: A Big Bertha modified to use 38mm motors and to go supersonic.
I hope to add to those ranks with my modified Big Bertha, which'll use 24mm and 29mm motors.


1) Great progress on the Orbital Transport. I cut the 5 balsa parts for the glider and assembled it. Because my only supply of BT-20 (till my Apogee order gets here) is 5.5" long rather than the 7" of the original, I modified the wings slightly to fit. I used barely any noseweight; a 1.5g slug of metal from my scrap bin and about 1g or clay worked well. I'm glad I made my own balsa tailcone / nozzle assembly rather than the paper of the original. It is far more durable than paper and was easier for me to make, plus the hole in the center allows for me to use a dowel-based booster for glide testing. The glide ratio is about 1.5 feet forward for every foot of glide at around 12 fps.

I also cut the wings of the booster out of 3/32" balsa. So far, I have the main wing sections, strakes, outer-wing flop panels, and canards. I think the Orbital Transport must have been inspired by the XB-70 Valkyrie. The resemblance is striking: long body; small canards, large delta wing, engines in sleek group(s) underneath the wings, and both flop-down wingtips and 2 large vertical stabilizers.

2) Repaired 16" orange parachute. It was burnt a bit on Rama's ill-fated last flight. There are 3 1cm holes from the ejection gasses, which don't really effect its performance. However, the ejection gasses also burnt the shroud lines. When I tested it today, both lines snapped. I replaced them with extra string and all is good.
Since I first posted this:

3) Made a 13mm balsa nose cone for a Mosquito clone. I'll fly it on MMX, and maybe once on a full A on a cloudless, windless day with several spotters, like at CATO.

4) Cut the aft wing section, ventral fins, dorsal fins, and some-little-reinforcement-bit-that-goes-on-top-of-the-wings. Now I've cut all the balsa for it except the ramjet pods.

Saturday, February 14, 2009

A Modest Proposal

Continuing on the theme of an earlier post, this is an open letter I plan to send to Estes. Any comments are welcome and will be integrated into the letter.

A Modest Proposal for Estes Industries

I recognize a number of needs - gaps in current motor selection - in the realm of low power motors, where Estes is the primary force and largest producer of motors. These include more booster motors, particularly in the type-A range; longer delays available on certain motors for use on very small and contest rockets; the return of smaller 24mm motors, larger booster motors for heavy model rockets and smaller mid-power rockets, and a greater variety of 1/2A and A motors. I also recognize that Estes has a unique position: the ability to introduce more varied, and perhaps less popular, motors while still turning a healthy profit, but also a need to produce motors that are popular and profitable. I believe that the suggestions I have here strike a healthy balance.
Stage 1: Replacement of Mini Motors.
The A10-3T and A3-4T are almost identical; of all current Estes products, only the Lucky Seven can use one (the A10-3T) but not the other. Instead, one, preferably the A3, should be replaced with an A10-0T booster motor, which from my experience is the single most-wanted non-production motor. It allows fliers to fly both 13mm and, with a simple adapter, 18mm rockets with 2 or even 3 stages in much smaller fields than with the current booster motor selection. In addition, the A10-0T uses the same propellant and nozzle configuration as the currently produced A10-3T and would be fairly easy to certify.
Additionally, the 1/2A6-2 motor is an almost useless and rarely-used motor. Very few 18mm kits use it; all that do are minimum-diameter models which would fly equally well on the more-common A8-3 and/or 1/2A3-2T. It should either be supplemented with the currently-OOP 1/2A6-0 and 1/2A6-4, which together make a useful set, or dicontinued entirely to open a slot in production for another motor - preferably an A8-0. Like the A10-0T, the A8-0 is extremely desired, useful for smaller fields, and will be easy to certify with the A8-3 and A8-5 already in production. These two changes would make many rocketeers happy, particularly the BARs desiring the smaller motors of their youths, and yet keep the current number of motors the same.
Stage 2: Booster Motors
Besides the two type-A booster motors already mentioned, several other booster motors are also highly desired, especially by the BARs who make up an increasingly large segment of the model rocketry market. These include the B6-0, C11-0, and E9-0.
The B6-0, similar to the A booster motors, is desired for small rockets and large fields. The C11-0 is also good for rocket like the Comanche-3; I would far prefer to buy a pack of C11-0s, a pack of B6-0s, and a pack of A8-5s and fly it thrice than only flying it on two stages for fear of losing it, or flying it on a D12-0 / C6-0 / A8-5 combination and standing a high chance of losing the upper stage.
The E9-0 is desired for a different reason: lifting larger and heavier rockets, particularly those with payloads. Currently, the D12-0 is the largest production booster motor, but is is limited to just 14 ounces at liftoff. An E9 or even E15 booster could lift far more and help narrow the gap between the current D12 and the F and G motors required for electronic staging.
Stage 3: The return of the C11s
The C11s are a sorely missed motor set; they were excellent for flying 24mm motors - which require larger rockets and therefore generate more profits - in smaller fields. Almost any rocket short of a heavy mid-power rocket will be lost from a football field on a D12 in even light winds, whereas it would be recoverable with a C11.
Stage 4: More Upper-stage Motors
With Quest having a limited selection and Apogee no longer producing its 10.5mm and 13mm micro motors, Estes is the primary source for 1/4A to D contest motors. However, for very light rockets for events like Altitude, Streamer Duration, and Parachute duration, the current upper-stage motors have insufficient delays. On a B4 or B6, an 18mm model with low drag may require as much as a 7.5-second optimum delay; using a B6-6 may rob it of up to 100 feet of altitude at ejection. On a C6 or D12, some require as much as a 9-second delay; for an E9, up to 10 seconds. I do realize, however, that for C6, D12, and E9 motors, the delay is already the largest that fits in the casing. However, were it available, I would happily buy a D12-9 in a 95mm long case or a B4-6 or B6-8. I also realize that contest-type motors like these are not Estes's specialty and would not be particularly profitable.

Update: I'll also add a suggestion to include 5 igniter plugs with the 4-packs of mini motors. It's nice to have an extra plug - it's easy to lose them - and currently 18mm and 24mm come with 4 - 1 extra, but mini motors do not.

(Insert obligatory salutory remarks here)

The Build Stack

Currently under construction:
Orbital Transport

Kits coming:
Madcow Mozzie

Need repairs, have parts:
RNGbane the Valkyrie
Gilder 2 (lost tail fin yesterday while glide testing)

Need repairs, parts coming:
Alexi Leonov

Planned scratch builds:
13mm saucer, 3" diameter
29mm saucer, 12" diameter
24mm saucer, 8" diameter (smaller than the previous one; designed for use as a lower stage)
18mmx2 cluster*
24mm machbuster**
13mm superroc***
13mm minimum diameter streamer duration / general flying rocket****
13mm WAC Corporal / Tiny Tim (design from NAR Guidebook)
MMX monocopter

Kits, not yet ordered, plan to build stock:
Dr. Zooch Saturn 1B
Dr. Zooch Saturn V
Apogee Heli-roc

Kits, not yet ordered, plan to modify:
Big Bertha*****
Estes Patriot (payload section and bulkhead)
Apogee Aspire (18mm adapter and 3/16 launch lugs)

Not very likely, but dream of getting:
Madcow Patriot
Madcow Momba or Cowabunga
Semroc Orbital Transport
Estes D-Region Tomahawk

*18mmx2 cluster: A pair of 18mm tubes about 18" long, inside an oval-squished 29mm tube 13" long. For a sort of dual deployment: a B6-4 with a streamer for slowing and stabilization in one tube, and a B6-6 with a parachute for lower, safer deployment in the other.

** 24mm Machbuster: A simple upscale of MMD, with a 24mm mount for a G80 or F55 (or similar), plywood fins, and one hell of an attitude. It'll also be a little longer, probably 18", for more stability with small fins.

*** 13mm superroc: a way to use up some of that 13mm tubing and tube couplers. For competition, 1/4A superrocs can be 25-50cm (10" to 20")(one 18" tube plus a 4-caliber NC max); 1/2A superrocs can be 50-100cm (20" to 39")(two 18" tubes plus NC max) and A superrocs 75-150cm (30" to 59")(up to 3 18" tubes plus NC max). I'll probably go for a 36" body and 2" NC, reaching 96 cm, good for 1/2A and A competition, yet not too long to carry and store.

**** 13mm general flier: currently my 13mm fleet is a monocopter, the medium-width but heavy Jinx, the fat but light Gauchito, the heavy and possibly unstable Cohete, and the heavy, short, and non-aerodynamic Rokit. None are thin, light, and sleek; i.e., good for streamer duration contests, general flying on 1/4A and 1/2A motors, or use as an upper stage (the Jinx gets burned by the staging blast because it's too fat). This'll be a basic, 10" long, 13mm model with swept fins and a largish streamer. It'll also be able to fly on MMX in my yard if I wish.

***** Big Bertha: Modified to take 29mm motors. Or maybe only 24mm motors, like Es and Fs. Like here, or here. I won't try a G (2900+ feet; questionable on a 3000' AGL waiver) or H (a mile plus, definitely illegal in CT), but an F will get me 2000 feet or so, okay on a windless day at CATO, and an E will get me about 1400' (E30, E9) to 1600' (E15). A D12-5 gets 930 feet with ejection right at apogee; 18mm composite D21-4s and D10-5s perform similarly for three to five times the cost. As a comparison, the recommended C6-5 gets 540 feet (500 at ejection; the recommended delay is 4 secs), 260 on a B6-2 or -4; 250 on a B4, and about 100 on the not-recommended A8-3 and A10-3T. (All simulations performed on the modified RASP-93 running on my calculator). I'll replace the stock 18" chute (12 fps descent; gone on anything above a C) with a 12" chute (17 fps) or 8" (26 fps; 250 foot drift from 1000 feet in a 5mph wind) chute, or even a large streamer for E and F flights. All fins will be reinforced with lots of wood glue; I'll put both 1/8" and 1/4" lugs on it.
I think I'll call it the Badass Bertha.

Friday, February 13, 2009

Launch Report #20

I built an 18mm monocopter and flew it twice on A8-3s....
It needs more of a B or C.
The first flight, the motor flew through the motor mount and flew 20 feet across the lawn. On the second, the motor stayed in but it didn't get above 3 feet. Sigh.
Oh, and a warning: with a fresh 6V lantern battery, an Estes continuity light bulb passes enough current to fire and Estes igniter. Adding a 100-ohm resistor in series with the bulb should make it safe.

Mystery Affliction solved?

So right now, I don't think my mystery affliction was really anything at all, and I don't think the two parts were related. The blisters on my toe have mostly disappeared, and I realized that they were exactly to be expected from wearing tight shoes, like when I wore a too-small pair for 11 hours on January 31st to the Berklee Jazz Festival.

Then, on Monday, I scratched my hand on a bit of plastic on a shelf at work, and I recalled doing the same thing, worse, right before the little blisters on my hand appeared. Since the scratch was right on the knuckle, every time I moved my hands stuff could get in and infect it a bit. Both parts are going away now.


I placed both orders at around 9 last night...
A bit before noon (before 10:00 mountain time), Apogee sent me an email with a question about my order, which cleared up a question I had about the free pack of nose cones. If you use the coupon code from the NAR guidebook to get the free pack of 24mm nose cones, don;t put them in your cart, but just use the code on checkout. As of 3:18 pm, my order from Hobbylinc shipped from Georgia. Customer service is impressive on both fronts.

Thursday, February 12, 2009


From Apogee:
Madcow Mozzie
Tubes o'plenty
Rings o'plenty
3-pack of 24mm PNCs -(the coupon code from the NAR Guidebook didn't work - I'll have to contact Apogee about that.)

From Hobbylinc:
A8-3 (2 packs)
C6-0 (2)
E30-4 Blue Thunder - for the Mozzie

All for about 180 bucks including shipping. A helluvalotta money, but 31 motors, including an E composite - the biggest, most powerful, and most expensive motor I've ever bought, plus a bunch of tubes, a bunch of parts, and 3 nose cones and a big parachute.


I got most of it back...
This morning I noted that it wasn't in the tree.....This afternoon I went and got it out of the bushes. The main body is undamaged. The motor as usual took a while to get out, but the rest of the body is undamaged except for a few missing decals and a broken shock cord mount. The shock cord didn't break, but merely pulled out of the paper mount. This means the nose cone and chute will stay up for a while. Fortunately, both are waterproof - only the rubber band shock cord and cotton shroud lines - which are replacable and them breaking will free the rest from the tree. If I can at least get the nose cone back, then SS1 will fly again. If not, And I can't get a replacement cheap, then it'll be retired. Unless... I get another one, use the extra tail cone as a tube coupler to lengthen it, and have an extra-long SS1.


is on tonight on Sci-fi! I gotta watch it of course, and I can cause I get to stay up late now. More later, maybe.

Tuesday, February 10, 2009


Gonna spend a bunch on rocketry soon:
Madcow 2.6" Mozzie: a 4.88x upscale of the classic tiny Estes kit. It takes 29mm motors but will fly on stuff as small as a D12-3. That means I can fly it to 200 feet and get it back for 3 bucks at the local field, on an E15 or E30 to 700 feet at CATO, or an F (1200 feet, risky but safe with the 18" chute) or a G if I'm crazy, or even an H to around 3000 feet at a BIG HPR field.

Bunch o' tubes: 6x 18" 13mm, 6x 18" 18mm, 6x 18" 24mm, 6x 13" 29mm. All for 26 bucks.
Bunch o' rings: 10.5mm/13mm, 10.5mm/18mm, 13mm/18mm, 18mm/24mm, and 24mm/29mm centering rings; 13mm, 18mm, 24mm, and 29mm couplers; and 1/8" and 1/4" launch lugs. All the stuff I need for proper motor mounts and maybe a 24mm superroc.
Plus a 3-pack of 24mm nose cones for being an NAR member and a 32" plastic parachute, which is not only the largest plastic parachute available for model rockets but too big for any or my current rockets...good for a 29mm saucer maybe, to see how slow I can get something to come down and still recover safely.

D12-3 - for the Mozzie
E30-4 - a Blue Thunder kick for the Mozzie

That's 23 motors, 1 rocket, 402 inches of body tube, a bunch of rings and things, 3 nose cones, and one big-ass chute, for around 150 bucks total including shipping. I've had good experiences with Hobbylinc on two previous orders and Apogee is renowned for its customer service, so I'll have all my junk within about 2 weeks.


I've got most of a rocket simulation program done. It can calculate the basic flight parameters on a variety of motors using RASP-93 code from the Handbook of Model Rocketry, calculate descent speed, time aloft, and drift on recovery, and display time-thrust curves for a variety of motors. Plus, my previous design program is integrated, as will be CP calculations soon. So far I have A6, A8, B4, B6, C6, and D21 18mm motors and D12, E15, and E30 24mm motors. I'll add 6mm MMX, 13mm 1/4A3, 1/2A3, A3, and A10, 18mm D10, and 24mm E6 and E9s soon. The simulator seems fairly accurate. It took few revisions to work perfectly: rearranging the motor selection so the thrust data would be routed properly, adjusting the algorithm to match time and thrust, and a few other minor tweaks. Except for a different and smaller motor set, it matches the behavior of RASP-93 perfectly. All in about 3K of memory. If anyone has a TI-84 or 83, maybe an 89, then I'll be glad to send you a text file with the code.

Monday, February 9, 2009

New Quest NE MMX Motors

Apparently Quest has introduced a new type or MicroMaxx motor called NE-no ejection. It appears to be a plugged motor for saucer-type models like IT, rather than a full booster motor. It's already NAR certified and only sold through Quest's website.I can't imagine too much of a market for it in MMX-only models, as being plugged limits its use to saucers and clusters (cause there's no way a MMX motor could lift staging electronics) or maybe really advanced stuff like rocket gliders or monocopters. However, It'd make a perfect outboard in a cluster of stuff like the Saturn 1B and V and hte Russian N1 / proton type boosters. Except for the scale models, I can't picture it having a heck of a lot of contest use. Still, I'm glad to see development with the 6mm motors. Especially since they come with actual Quest Q2 pyrogen-tipped igniters rather than the hard-to-fire hot wire igniters the normal ones come with.

Computer Problems

My computer has been a bit funky for the last few days....That's why I haven't been blogging much. It crashed twice when superfetch - a Vista application that helps load application files faster - stopped working. Withing 10 seconds, both times, I got a Blue Screen of Death Error. The second time, after it crashed, I ran Disk cleanup and defragged. Disk cleanup deleted 5 GIGS of program files and cookies. I suspect that a majority were .kml and .xml files for Google Earth - I've been running flight sim on it a lot since june without deleting all the downloaded files. Hopefully all will be well now.
Computer problems always scare me and this one is no exception. I'm a bit down right now, but all should be fine in a day or so.

Sunday, February 8, 2009


As my friends may know, I'm in the LHS Jazz Band. Today, we got to play as part of the opening ceremony / viewing event for the Extreme Makeover Home Edition which came to our area to help the Girard family, who lost their father, son, and home in a few horrible months. We got to play our set on one of the largest and fanciest stages in the area - where they have had some of the biggest names in music - and we got treated basically like celebrities. I'd like to thank the MGM Grand casino for having us and treating us so well....and I'd like to thank the academy.

Maps of the internet

Very Cool.
One is already set as my desktop.

Saturday, February 7, 2009

Launch Report #19: A sacrifice to the rocket gods

Today was the warmest day so far of the year - 48°, and less than 2" of snow on the ground. It, unfortunately, turned out to be a crappy day for rocketry.

I used my new 6V battery for all launches. It worked great, but I need to get a new light bulb for it.
First was the body of Frankenstein on an A8-3 carrying an SR-71 nose cone modified to be a lifting body It rose about 30 or 40 feet, burnt out, fell back to the snow, hesitated a second, then spit out the motor upon ejection. Nothing was damaged. I'll make an 18" long booster for the lifting body with extra-large fins.

Frankenstein, however, has a date with death. As part of a deal with a friend, it'll be launched into oblivion on either a C6-0/C6-7 or D12-0/C6-7 combo, with the entire forward body tube full of pink tracking powder. I hope to launch it high enough to never see it again but still see the brightly-colored cloud.

Next came Rama on a C6-3:

This picture, excellently taken by my dad, looks good, but it arced over starting during thrust (heavy rocket + 10 mph winds + underpowered fatass = disaster) as ejected just before impact. Nothing was damaged, but now I'll either convert it to a 24mm mount, try a D21-4, or only launch it in very calm conditions.

Here's me loading Alexi Leonov:

A few things to be seen in the photo: using a towel as a working surface for winter rocketry, the extension cord 'plugged in' to the 6V lantern battery, and SS1 sitting on the lid of the copy paper box I use to transport rockets.

Fly me to the moon...

Here's Alexi Leonov taking off on a B6-0. Unfortunately, I forgot to insert the second stage motor.....
Fortunately, the booster motor kicked the booster stage off, pushed the nose cone off the sustainer, and kicked the chute out so both pieces came down safely. Inside the payload bay was a sonic finder consisting of a beeper from an old motherboard and a 3V battery.

On its second flight of the day on a C6-0 / A8-5 combo:

That was the one perfect flight of the day. Ejection was just past, and both parts touched down safely although the chute didn't deploy. The upper stage motor mount was fried by the two booster motors and must be replaced before it can fly again.

Finally came SpaceShipOne on a C6-3. Forgetting how light it is and how high it goes on a C, I stuffed a 24" homemade chute in it. Ejection was perfect; it fell for a few seconds before the chute deployed and then away it went. It drifted forever on the 24" chute - across the field, over the street, and into a tree, 60 feet up.

I can't climb the tree or use a ladder, and both shotgun recovery (shoot the branch off the tree) and chainsaw recovery (chop down the tree) aren't gonna happen in someone else's yard, it's stuck for now. The rubber band shock cord will break in a few weeks, so I can hope to get the plastic tail cone and nose cone back at least; by then the body tube, motor mount, and fins will be mush or warped beyond repair. The string plastic parachute and cotton shroud lines might stay up for months or years.

The homeowners weren't home, so I didn't go too close to look, but it looks to be well-tangled. I'll stop by tomorrow and either leave a note or talk to the homeowners. This was my first sacrifice to the rocket-eating trees (previously the digester of Charlie Brown's kite); everything else has either come back safely or crashed.

Total damage of the day: 1 crashed but undamaged, 1 crashed, slightly crumpled, and way underpowered, 1 with a charred MMT, and one in a fine tall fucking oak tree.

Current totals: 375.12 Ns (14.1% I) total, 70 flights on 82 motors, 4.57 Ns (82.8% B) per motor and 5.36 (7.2% C) per flight.

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Launch Report #18: Spiraling Pyrotechnics

I flew the Whirling Dervish twice today, both on A3-4Ts. It's a great motor for it, although it does eject on the ground. Both flights used my new 6V battery. It fires Estes igniters almost instantly; although slowly when cold. The first launch was around 3 pm after school. I had added a 6" or so extension to the wing. It flew about 20 feet up and 40 sideways, making a nice thop-thop-thop sound. It unfortunately alsi rebroke the launch pad. I have thoroughly reglued it, but I'll get an Estes E pad on an Aerotech Mantis pad sometime soon for a better replacement that can take MPR motors, particularly Es for flying a 29mm rocket at my main flying field.
For my second flight, I stuck a 4" length of 1/8" hollow aluminum rod into a chunk of 2x44 for the pad for a 2" usable rod; I put a 1" piece of plastic straw on to limit the rod to 1" and keep the monocopter from hitting the pad. I flew it around 6:30 at night; it was dark except for moonlight. I'd left the 6V lantern battery out in 10° weather for too long, so I had to bring it in to let it warm up first. It still ignited slowly because the cold battery didn't produce much amperage because the cold slowed down the chemical reaction. It was rather awesome in the dark; it rose to about 15 feet under power then fell back to earth. I'd never done a night launch before. Monocopters are good for flying in the dark as they're low, loud, firey, easily found, and would make for AWESOME pictures. The ejection on the ground was rather spectacular. I'm starting on an 18mm version now.
So far: 76 motors on 65 flights. 339.92 Ns, 6.23% I, total, equaling 4.47 (82.8% B) per motor and 5.23 (4.6% C) per flight.

Thursday, February 5, 2009

Google problems

From yesterday afternoon till today I had problems with Google....couldn't get to the search page or my gmail, sign into blogger to post, or use google earth. It appeared to be local - resetting the router seemed to do it, and a friend a mile away using the same ISP could still get to google. No other web pages were affected, except for the Questionable Content site, which now also works. I had 8 emails - a record for me.
By the way, this is my 200th post in 242 days. That's 0.826 a day, or about 300 per year, although my frequency is increasing.

Tuesday, February 3, 2009

Mystery Affliction

Anyone have any idea what this is:
For about 2 weeks I have had 3 blisters on my right pinky toe. No coming, no going, just appeared there one night. Don't really hurt. Two are small; one is larger and has a pea-size volume of fluid inside. All are pink. During the same time, I've had several smaller fluid-filled bumps on the inner-most knuckle on my right middle finger. Don't hurt, don't change, just are. This is truly a WTF? affliction.

Launch Report #18

I am one crazy bastard. I flew an untested rocket with an untested ignition system. In my yard, which is far too small to fly an A3-4T in. In a blinding snowstorm. I have found the zen of winter rocketry.
My rationale: I wanted to test the new ignition system I built. I had to do it in my yard as the roads were nasty. I didn't have any MMX motors; the smallest I had were A8-3, A3-4T, and A10-3Ts. I didn't want to fly my 18mm saucer cause on an A8-3, which I have too many of, it'd go about 20 feet and that's boring. So I decided to build a monocopter, a funky thing with a motor on one side and a tilted wing on the other.... check out the collection on EMRR here. All it took was an index card for the motor tube, a few pieces of balsa, and a drilled hole for the launch lug... And I have the whirling dervish.
I set up real quick to fly it. I used a 2" long piece of 1.8" metal rod for the launch rod... monocopters don't need much. It ignited quickly, spin rapidly, rose to 2 feet off the ground, and landed 10 feet from the pad. I turns out, between a too-small wing and catching on the pad, it ripped part of the base off its mountings, flung it 5 feet, and burnt out before it could go very high. A bit of krazy glue and the base is fine. The Whirling Dervish will fly again, on an A10-3T for a faster start and more altitude, witha larger wing to get it off the pad, and a straw underneath on a slightly longer rod so it won't hit the pad.
So far: 335.2 Ns (4.75% I) total. just about the same per-flight and per-motor.

New ignition system

I finally got it all hooked up today...6V lantern battery attached to an old power cord, attached to an old Estes launch system. It fires Estes igniters in under half a second. I can probably use plain 30+ gauge wire as hot wire igniters, especially for MMX motors, and fire 2 or 3 motor clusters using Estes low-current igniters. With another 6V battery hooked up, I can even fire composite motors with Aerotech Copperhead igniters. Unfortunately, the stock bulb is burned out, so I'll have to get a new one at Radioshack or something.
I gave it a nasty test today - firing an igniter in a snowstorm at 30°F. It worked great. More details in the above launch report.

A Funny Guide to Skeptic Etiquette

Via Cocktail Physics comes this funny guide to being nice to those who are not as scientifically skeptical and intelligent as you, by Allyson Beatrice. It's a nice guide for social situtations, and also funny as hell. A few quotes:

Eventually, she tried exorcism (to which my only reply was, “Uh, don’t you have to be Catholic for that?” because seriously, what else can you say?)

About astrology:
You do realize that Jupiter and some random stars have no effect at all on you, right? I mean, why is it that you’re protected from the magical personality rays of the constellations when you’re buried a few inches deep in flesh and fat, but the second you come screaming out of your mom, the magical personality rays pierce through the brick, mortar, insulation, tile, and electrical wiring of to the third floor maternity ward of the hospital in which you have emerged to touch you with the magical essence of “Taurus,” you stubborn little baby bull!

One of my neighbors joined me for a drink one night and launched into an excited explanation of astral-projection. She had spent close to a grand on classes and had her first out-of-body experience. I have no poker face. None. It’s not that she didn’t have the money for such things, she makes plenty of dough and could just have easily spent it on new shoes without hurting her savings account. But she wanted to talk about this revelation, and my response was, “Sweetie, you had a hallucination. You paid a ridiculous sum of money to have a hallucination. You can get a bag of ‘shrooms for a tenth of what you just spent, and had enough cash left over to buy new shoes, too!”

This devolved into an argument on the “science” of astral-projection, and she swore that she has read many studies on how it is a fact, A FACT, that one’s mind can ski on out of one’s body and, I dunno, look up ladies’ skirts on the escalator at the mall.

She also has this marvelous quote that's not funny but very meaningful:
I told her that the universe is wonderful enough on its own. Space, stars, planets, black holes, galaxies, suns. The fact that out of all the elemental soup, people like us have evolved to walk and talk and create art, music, white wine, patent leather stacked mary jane shoes, Cocoa Puffs cereal, truck nutz, chocolate chip cookies, surf boards, and the Neiman Marcus cosmetics department is AMAZING. All by itself. Saying, “god did it” is heartbreaking. It pisses on the sheer wonderousness of it all, you know? I don’t need more.

Visual Simulation Program

I've written a neat program for TI-84 series calculators to visually simulate the appearance of rockets. It can do conical and ogive nose cones, body tubes, transition sections and tail cones, quadrilateral and triangular fins, gaps in the body, and side pods with nose and tail cones. I can sim stuff up to 37.5 units long. I've managed to do odd stuff like multistaged rockets like Comanche-3 and Alexi Leonov, top views of gliders, a nice-looking Patriot, and even really cool ones like the old Estes Trident.
If anyone wants the code, drop me a line with a comment or my email as linked at the bottom, and I'll send you a text file with the code.
Next comes code for launch lugs, glider hooks, and pods on one rather than both sides of the body.

Monday, February 2, 2009

Launch Report #17

It got up to 48° yesterday, so I celebrated by going out and flying more rockets. I flew 6 rockets on 6 motors on 6 flights; no 2-stage flights and only my glider separated.
All of these pictures but two have been modified with the 'I'm feeling lucky' process in Picasa; it makes the picture clearer but slightly off in color and texture and sacrifices some detail. As always, click to embiggen.
First came Jinx on an A10-3T; a prefect flight to about 250 ft, although the chute didn't deploy, it was just fine.
Second came my Glider #2 on an A8-3. This is too long a delay for it, but I didn't want to risk it on a C6-3 and I was out of B6-2s. I but a spacer in the hook so it stays on the pod all the way to ejection; this worked well.

It arced over after about 2 seconds of delay, ejected nicely at around 150 feet, and separated cleanly; in 4 flights I've never had a red baron - tangle - with this pod even though it's rather short. The glider flew well - about 15 seconds and 300 linear feet - and I caught it perfectly half a second before landing.

My Rokit - a joke made out of an old engine casing and fins that look taped on - flew nicely on a A10-3T despite its weight; it'd estimate 250 feet or so. The string shock cord snapped below the streamer; the body came in ballistic while the nose cone came down slowly on the streamer. I replaced the shock cord with 1/4" elastic and took 1/4" of crushed tubing off the top of the body.

Here's it just building up thrust about 0.05 second after ignition. This is the unmodified version...
And this the filtered version. Notice how the processing made the picture more aesthetically pleasing but because of the single very bright spot made the rocket very dark and made the picture a tad grainy.

Next came the Wizard on an A8-3. I managed to track it all the way to apogee, ejection, and back; before I had never done that even on an A8-3. I will soon drill out an 18mm casing to accept 13mm motors to fly it on a 1/2A3-2/4T. The 2-second delay will be too short; the -4 too long. I'll get the -2 pack so I can fly them in the Jinx and Gauchito.

OV10 on the pad.....

And again... I had to position the clothespin perfectly so it wouldn't snag the tail; I had to readjust it twice bacause of the wind, which by that time was around 5 mph in gusts.
It boosted straight and fast on a B6-2, but the pod didn't slide back and it came in ballistic. I'll have to reglue the engine block, nose cone, and both centering rings, but everything is ok. I might modify it so the pod will lock better in glide position.

The newly rebuilt Screaming Yellow Zonker! on the pad. The spin fin is the one behind on the left; the launch lug is behind the fin on the right - I didn't want to put it originally on the spinning sustainer - now the yellow main body - for fear of unbalancing it.

The unmodified version of it under full thrust on the pad..
And modified. The igniter is still burning fiercely! I plan to buy a cheap tarp to ward against grass fires during the summer. Since the rocket is mmoving around 30 mph and it moved about 1.5" during the picture, I can deduce that the shutter speed on the DSLR (digital single-lens reflex) is about 1/250th of a second on the action setting.
The SYZ! made a nice thop-thop-thop sound during boost and it spun all the way up till ejection. It boosted fairly straight despite the wind - a trademark of spun rockets - to around 800 feet or so. Ejection was nice, around apogee but I'm not sure as it was just a black dot. The streamer unfurled nicely and it landed about 400 feet away, just 30 feet from the menacing treeline. I think a B6-4 will be a better match for this for a nice spin but safer, closer landings.
Since September 29, 2008, I have flown 32 distinct rockets - 29 rockets and 3 boosters that don't go with a certain rocket - on 56 flights on 73 motors for 333.32 total Ns - almost exactly 1/3 of the way to 1000 and a 4.2% I total impulse. That's 4.57 Ns (82.8% B) per motor and 5.95 Ns (19% C) per flight.

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Sunday, February 1, 2009


Saw Venus in broad daylight today....hud the sun behind a building, found the moon, and looked halfway in between them... nice way to find it today. It was an almost invisible white dot, barely brighter than the surrounding sky.
Also, for those local folks, it IS possible to see both casinos at once...from about 500 feet of I-395 around here. I suspect there may be somewhere in Ledyard also; I'll try sometime.

Mach My Day - New Colors!

I did some color work on my machbuster - red forward body, and red, yellow, and black alternating opposite their colored fins on the lower section. That should make it easier to spot on descent if it survives.
I also put my address, name, email, and this blog's address on it... so if you happen to find a small; red-white-yellow-and black rocket either near Ledyard Middle School field or near White's Farm in Durham, drop me a line.
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Notes From the Lab

Did a lot in the last few hours...

1) Made a 2-caliber parabolic 18mm balsa nose cone for the Orbital Transport. Pretty good, but about half a millimeter lopsided.

2) Made a small hollow balsa tail cone for the glider to replace the paper shroud in the original. Again, a bit lopsided but nice-looking.

3) Sanded and CA-sealed the BNC-20 I bought for the OV10 but have since replaced. I'll use it on something that doesn't put a lot of stress on the nose cone, i.e, doesn't glide.

4) Made 3 13mm and 10 6mm engine blocks out of old motor casings and dowels. The 6mm ones require drilling out a 1/4" dowel with a 9/64" drill bit... tricky. The secret is to spin the dowel in a drill and hand-hold the bit.

5) Combined wood glue, balsa sawdust, and water to make a paste. Put it inside an 18mm casing to try and made an artificial wood bulkhead.

6) Mixed old motor nozzles, water, and some carbon from the motors. It smells nasty. Put outside to set.

7) Print out balsa fin pattern, cut dowel, launch lug, connector tube for the Orbital Transport. I've now got the main body tube, BNC-50, motor mount, launch lug, glider tube, glider NC, glider tail cone / fake nozzle; dowel, tube and standoff for connecting glider and booster; and the 4 ramjet tubes ready. Balsa cutting tomorrow.

Estes NC-5 Shapes

Because there's no good pictoral guide...I've decided to make one. NC-20, 50, etc coming soon.
A shape-rocket chart is here.
Plans and pictures from JimZ and Ye Olde Rocket Plans.
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