Estes is having a photo contest!

All you have to do is to mosey over to their web site and submit an image of yourself - or someone else - launching a rocket. The grand prize is $575 dollars in rocket goodies. You can only submit one entry and the contest ends on July 19.

The grand prize in the estes photo contest.

I have lots of rocket pics, dating back years. So one would think I would have many, many images to choose from. Turns out, if I

1. strictly adhere to an image of myself or someone else launching a rocket, and
2. spare the public the horror of a selfie

there's not so much. I have lots of rocket launch pics, but not that many with people pressing the button. Been focussing on the rocket, ya know. Anyway, I did narrow it down to one of the below - which one would you have submitted?

Returning a veteran to duty...

In 1972, Cox (which was then a separate company from Estes) offered a line of all-plastic ready-to-fly model rockets, many of which were scale models. My rocket builds looked like crap back then, so I was all about good looking birds that I could fly immediately after taking them out of the box. Thus I acquired my first Cox model rocket, the red and white Honest John. It was not a member of my fleet very long, borne away by the wind after being lofted to altitude on a C6-5 (My fleet was very small in Jr. High - I was in the "stick the biggest motor you can into it" phase, which meant most of my rockets sailed away well beyond the bounds of our small neighborhood flying field). A few years later I bought a Cox 1/125th scale Saturn 1B, which made several flights on dual C6-3's. Being all plastic, it was rather heavy, at about 6 ounces. One did not dare attempt to fly it on a single 18 mm Estes or Centuri motor - they simply did not have the power to loft the Saturn.

The Cox Saturn 1B, released in 1972 (Click to enlarge).

Flash forward to 1989... I had been introduced to composites at NARAM 30 the year before, and I was eager to try some of these motors out. The Saturn 1B had miraculously managed to hang in there with me, and I thought that it might be the perfect vehicle to try out one of the 18 mm Aerotech E25's (I had considered sticking one in an Alpha, but figured it would be an embarrassing shredsville). So I gathered together my compadres and we trekked out to a field just outside Gainesville, Florida for my momentous entry into the world of composite rocketry. The Saturn was placed on the pad, the count given, and the launch button pressed.

It took off like a bat out of Hades, riding a pillar of white fire, accompanied by a very satisfying roar.

There was much applause - until the shock cord broke.

The large bottom part of the rocket descended safely under the parachute, but the upper piece (LEM shroud, service and command module, and LES) tumbled to the ground. Naturally, the escape tower broke off on impact. "No problem" I thought - "I'll just glue the escape tower back on." However, an inspection of the lower part of the Saturn showed that it too had suffered damage - but not from hitting the ground. The heat of the Aerotech motor had melted one side of the model, and a piece of the upper bulkhead was missing, blown away by the ejection charge. The interior looked like I had dumped a bag of soot into it. Apparently, the Aerotech motor was too much for the rocket, in a lot of ways.

I still have an old Aerotech E25, similar to the one that scorched/melted my Saturn.
Don't know what to do with it, but it has to be something special (Click to enlarge).

And so I consigned my injured Saturn 1B to the box of misfit rockets, where it has lain for 30 years.

The Apollo 11 50th anniversary is next month, and, like many of my kind, I have purchased a 1/200th scale  ready-to-fly Saturn V from Estes. It has a couple of things in common with the Cox Saturn 1B - 1) it's all plastic, and 2) it's a pig, weighing 4.5 ounces without motor. Estes recommends only a C6-3, but the weight of this rocket is well above the maximum lift-off weight for a C6 listed in the Estes catalog (4.0 ounces - the Saturn V would weigh in at 5.3 ounces with a C6-3 loaded). So my model will fly on an an Aerotech D10-3W or a Quest D16-4.

The melted part of my Saturn (Click to enlarge).

The damage to the forward bulkhead (Click to enlarge).

However the thought of switching from a BP to a composite motor brought to mind my old Saturn 1B, so I dug it out of the box for a dust-off and a new inspection. After all, it would be a nice add if I could fix it up and fly it on the Apollo anniversary. The damage was as I remembered, but I figured gluing the escape tower (which was taped to the rocket - a rare bit of organization) would be easy with Plastic Weld and I could prevent further melting by installing a stuffer tube inside the model. This will preclude flying the Saturn on dual motors, but there are now plenty of 18 mm composites, so no great loss. I Frankensteined a stuffer out of a length of BT-20, with segments of BT50 and ST-10 at each end (the BT50 and ST10 tubes were chosen because they fit the bottom and top bulkhead openings). The stuffer tube was glued in using 15 minute epoxy - while this dried, I glued on the tower using Plastic Weld. The final steps in the repair were attaching a new shock cord to the pre-fab attach points and adding a few grams of clay in the nose to compensate for the weight of the tubes.

Assembled stuffer tube
(Click to enlarge).

Installed in the Saturn (Click to enlarge).

She's now ready to fly - I think I'll be using an Aerotech D21-4 for the flight.

The repaired Saturn 1B
(Click to enlarge).

July is looking to be a very fun month!

Oeuf and Ool

As I mentioned in my previous post, I have started designing and building my rockets for this year's Geezer TARC. The first of these, Oeuf (french for "egg"), is an Alpha-like model based on the Centuri ST-18 body tube (minimum diameter for a regulation TARC egg). It's powered by up to 4 18mm motors, though OpenRocket is saying two D motors will be sufficient, provided I don't exceed the design weight. If I do,  I can always put A, B, or C motors in the other two tubes - Oeuf ain't nothing if not flexible. Right now, she's waiting for her first primer coat to dry.

OpenRocket visualization of Oeuf during dual motor thrust (Click to enlarge).

I have just started work on the second design, called "Ool" after the name for food in one of my favorite movies, "Caveman." Ool is a 3 finned BT-55 to BT-70 rocket, propelled by a single 24 mm motor. She's designed light, a tad over 200 grams without motor, and will sport the Apogee conformal rail guides - a first for one of my rockets. OpenRocket is projecting that a single E12 will provide more than enough juice to make 800 feet; thrust-to-weight is an acceptable 4.7:1, close enough to the magic 5:1. Motor mount is assembled, body tube spirals have been filled, and the balsa fins have been cut and skinned. I originally had smaller fins, but they struck me as too small, even though the sim was telling me the static stability margin was 1.5 without the egg and altimeter. So I upscaled them by 125%, which appeased my rocket instincts and improved the stability margin up to 2.1 without the payloads.

Visualization of Ool under E12 power (Click to enlarge).

Yeah, I know Open Rocket said it was stable, but I have seen too many TARC rockets that were rated as stable by the sim go very squirrelly after leaving the rail. Not going to happen with one of my birds.

I hope to have the fins on Ool tomorrow and to apply primer sometime during the upcoming week. Depends on if we can get a break in the recent bout of stormy weather.

Geezer TARC has started!

Now that the rules have been released for the 2020 TARC competition, the annual Geezer TARC contest can begin. I'm looking forward to it, and encourage anyone interested to participate. Who knows? You might be crowned the new TARC Geezer, or maybe even win the coveted Skunk trophy, given to the contestant with the biggest mess…er, most interesting rocket or flight.

The rules are the same as those for the 2020 TARC challenge (link to rules) with the following exceptions:

1) Geezer TARC begins with the announcement of the 2020 rules in May and ends with the contestants’ rockets being launched at a single event (date TBD, probably on a Saturday on or near the start of the college football season in September).

2) The altitude goal shall be 800 feet and the duration goal shall be 40-43 seconds. Geezer TARC was never intended to simulate Nationals, the focus being on what it takes to qualify. This practice will be continued this year, as it will help the mentors guide the local teams in their practice and qualification flights. Besides, we have enough trouble hitting the altitude mark even if we explicitly design for it.

3) Each contestant may enter up to two rockets. These rockets may not fly before the official launch date, and the score shall be determined by the first flight of each on that date. The contestant's score shall be the better of the two flights, or the score of one flight if only one rocket is entered.

4) Contestants must use one of the regulation TARC altimeters (APRA, PNUT, or Firefly) as the "official" measure of altitude. A re-flight will be allowed in the event of an altimeter malfunction, provided the flyer can demonstrate it was not his or her fault (i.e., did not forget to turn it on or provide vent holes to the outside). The altimeter used to record altitude may be used for no other purpose, though the use of a Jolly Logic Chute Release or other altimeter type/flight computer is permitted for flight control.

5) There is only one rocket per design, and there are no test or sub-scale flights permitted for the design. Its merit will be judged solely by the rocket’s performance at the contest launch. If two rockets are entered, they must be of substantially different design - different number of motors, fins, or something major - an inch shorter or taller does not constitute a substantial difference, nor does the same design at a different scale.

I am in the midst of building my first design - an Alpha-esque, 4 motor beauty I call "Oeuf." That's french for egg, and it also sounds like what I may mutter if one or more motors fail to ignite. Still working on design #2.

Let the fun begin!

A new season and a new name...

The 2019 TARC rules were released the evening of Nationals, and I must say that there were a couple of surprises. First was TARC now stands for something else - no longer "Team America Rocketry Challenge", it is now "The American Rocketry Challenge" And with the new name comes a new logo:

The qualification flight goals are fairly simple - single egg to 800 feet and down in 40 to 43 seconds. Rocket has to be painted and at least 25.6 inches long; all parts must come down together under parachute. This is easily accomplished with an E motor, so I was wondering what the catch was until I saw the rules governing Nationals. There's where the second, and biggest, surprise lay. Used to be the first round at Nationals was simply a repeat of the qualification flight marks - no longer. Teams making it to Virginia this year will have to meet a first round altitude goal of either 775 or 825 feet and duration intervals of 39-42 or 41-44 seconds, depending on the results of a coin toss. Nefarious, as this will require the teams to know how to adjust their rocket's altitude in order to have a chance at making it to round 2. This means they are going to have to make extensive use of their flight data - or come up with 3 models, one for each altitude mark.

So what would be my advice to the local teams?

1) Focus on getting good qualification scores - In order to win, you have to first make it to Nationals. Get them done as early as possible!
2) Record everything pertaining to the flight - weather, weights, launch rail angle - everything. Use a PNUT altimeter to get a complete flight record.
3) Learn how to interpret the data! Figure out how to adjust the rocket or rail to consistently achieve the desired altitude. Possible changes include

• Ballast weight
• Rail angle
• Nose cone shape

I can't emphasize #3 enough - our teams in the Huntsville area spend plenty of time practicing (to the point that they run out of motors), but often it seems like they are just randomly putting rockets into the air. Data is logged but not used. That will need to change if they are to advance to Nationals this year.

Time to break out the math skills!

Goodbye Pegasus!

You can see the construction going on at the former Pegasus field behind the Urban Astronauts, who are holding
their rocket high after completing their TARC qualification flights.

Well, my last post couldn't have been more wrong - Life took a significant downturn starting the first of the year, and I'm only now to the point where I can turn my attention back to my rockets. I did spend time with the local TARC teams this winter and spring - can't shirk my duty as a TARC observer - but my stuff languished on the workbench. Hopefully things are stabilized; I could use a little more fun!

Anyway, we have lost Pegasus field - at least the good western part of it. Construction on the Blue Origin rocket engine factory began in earnest in January, which put an end to all flying there. Some of the TARC teams found another field on the northeast side of Research Park - which is now plowed - while others made do with the smaller field across the road from our former launch site. It was able to accommodate TARC flights - barely - and we didn't loose any rockets to trees. I suppose the good news is that we are still able to fly low/mid power birds in Research Park, but I must confess to missing flying at Pegasus. However, if you are going to loose a field, having a rocket plant built on top of it is a better reason than most.

If only the weather would cool down a bit...