More scale modeling...

Hawk missiles on their launcher (Click to enlarge).

At the December HARA meeting, Elliot Laramie gave a tech talk on the Hawk anti-aircraft missile, which was first deployed way back in 1959. Despite being nearly 60 years old, the missile system has undergone improvements over the years - the last major one being in 1995 - and is still in use by several countries, including Egypt, Israel, Saudi Arabia, Turkey, South Korea, and Greece. The U.S. phased out the Hawk in favor of the much more capable - and way more expensive - Patriot in 2002. However, the cost of the Patriot is such that many countries with Hawks are opting to go with far cheaper upgrades to their existing missiles rather than buy Patriots. This is for good reason - the Hawk has proven itself to be a decent anti-aircraft weapon over the years, with over 80 kills. Jane's gives a single shot kill probability of 85% for the 1995 Hawk. However, as any missile man could tell you, Hawks are launched in pairs or more, adding to the lethality of the system.

There have only been a few flying scale kits of the Hawk produced - Estes produced a not-even-close-looking Army Hawk from 1990 to 1992, and The Launch Pad put out a much better kit of the MIM-23A version, but this one is very hard to find with the company now out of business. However, scratch builders have better luck, as Peter Alway gives plans and tips in his "Scale Bash" booklet for constructing a Hawk in one of 4 different sizes (BT-5, BT-20, BT-50, and BT-55). This Hawk information is shown in the scanned image below.

Hawk page from Peter Alway's "Scale Bash" (Click to enlarge).

Acting on a whim, I took the dimensions from Peter's BT-55 version and entered them into Open Rocket. I found that the rocket required a lot of nose weight - 70 grams - to get a decent margin of stability with a D12 motor. This amount of weight jives pretty well with the Alway notes, which state that the CG needs to be 9.4" from the nose; my CG is 9.0" from the nose with a D12-5. I went with a 24 mm motor mount because you can always adapt down to smaller sizes, and because I liked the performance (900 feet) on the D12.

Open Rocket sim of a BT-55 based Hawk (Click to enlarge).

Open Rocket rendering of Hawk in flight (Click to enlarge).

I suppose that I must add this rocket to the build list, given that I went to the trouble of simming it in Open Rocket and also because it would make a nice addition to my collection of scale models. If you happen to be interested in building one for yourself, my Open Rocket file can be downloaded from here.

Warm December launch at Pegasus...

(Warning - this is a long post with many pictures)

Some of the activity at Pegasus field this Saturday; the Jurassic TARC team is in the foreground (Click to enlarge).

Huntsville has been experiencing a period of warm weather with little wind of late - a phase that is projected to end this Tuesday. Yesterday's conditions were so good, they positively demanded that rockets be put in the air, forcing me and Duane to join some of our colleagues and a couple of TARC teams at the field for some flying fun. We arrived at noon, and the next couple of hours saw a lot of activity, so much so that I had a hard time keeping up with it. What follows is a brief summary of that launch, which I figured I'd better post before I forget many of the details.

Duane giving advice to some members of Jurassic TARC (Click to enlarge).

"Velocity Raptor" on the pad (Click to enlarge).

"America" is launched (Click to enlarge).

The Falcons setting up their range table (Click to enlarge).

The two TARC teams turning out onto Pegasus yesterday were both familiar, being Duane's Falcon Rocketeers and Jurassic TARC from Pope John Paul II High School. Saturday saw their first practice flights, with each team getting one - and only one - flight in. Jurassic TARC launched first, and their "Velocity Raptor" rocket struggled to reach 691 feet on an Aerotech F42. Might have had something to do with the too-short 4 second delay, which also caused the shock cord to pull loose from its mount, sending Velocity Raptor back to the Mesozoic Era. The Falcon Rocketeers had their rocket - the red, white, and blue "America" - ready a few minutes later. The F42-8 motor powered it to an altitude very close to the goal - 808 feet - but the payload section pulled free of the sustainer, causing the payload to tumble to Earth. It too was out of action; hopefully these teams can overcome the bad mojo next time out.

"Fat Chance" starts its first successful flight (Click to enlarge).

Speaking of Duane, he only flew one bird. Determined to show that he could actually have a rocket land safely, he brought out "Fat Chance", equipped with a new shock cord mounting system. Fat Chance put in a beautifully straight flight to 862 feet on a F32-6, and held together at ejection. Both parts of the rocket made a gentle landing under parachute, and we congratulated Duane on breaking his curse (which seems to have transferred to his TARC teams).

Allen launches his Estes Patriot (Click to enlarge).

The Mammoth leaves the rod with camera and
telemetry active (Click to enlarge).

Frame from the Mammoth's onboard HD camera (Click to enlarge).

Another frame from the Mammoth camera (Click to enlarge).

The Inductor leaves the rod, its Aerotech D10 leaving a trail of black smoke (Click to enlarge).

Allen brought a slew of rockets to fly, and their performances did not disappoint. His A10 powered Sonoma (an Estes Sequoia with adapted decals) led off, followed by his venerable semi-scale Patriot on a B6-4.  He then launched his Mammoth on an F42, which was fitted out with a Missile Works T3  tracker system and an HD video camera. The T3 worked well, and the camera recorded some decent onboard video, which you can view here. A flight of his finless induction rocket (the "Inductor") was next; the Aerotech D10 motor chuffed quite a bit before building enough thrust to loft the model, which started doing a big loop in the sky at motor burnout. 

The QCC Explorer rides the fire of a D12
(Click to enlarge).

The Fletcher clears the rod on an A10
(Click to enlarge).

Allen's Skydart II on the pad (Click to enlarge).

Liftoff on the B6-4 (Click to enlarge).

The Skydart glides in for a landing (Click to enlarge).

Frame from the HD camera on the QCC Explorer (Click to enlarge).

The video camera got another workout taped to the side of Allen's Estes QCC Explorer, which went surprisingly high on a D12. However, I would have to say his most impressive flight was made by his Estes Skydart II; powered by a B6-4, the model flew arrow straight, with ejection of the power pod occurring right at apogee. The Skydart settled into shallow glide, moving in a wide lazy circle over the field for about 30 seconds. It was the best flight I have ever witnessed a Skydart make, and I congratulated Allen on his trimming skills. He also flew his Estes Fletcher (painted camouflage) on an A10, and risked his QCC Explorer on an Estes E9, but those flights - good as they were - were nowhere near as awesome as that of the Skydart.

"Purple Pink" is launched (Click to enlarge).

"Starshooter" clears the pad on a B6 (Click to enlarge).

Razor's A3 motor ignites (Click to enlarge).

"Shockwave" heads up into the sky (Click to enlarge).

Marc's Screaming Mimi on a D12 (Click to enlarge).

Big Bertha rises majestically on a C6 (Click to enlarge).

Marc had his son and daughter along for this launch, and it was his daughter's "Purple Pink" which started his series, flying on a B6-4. That same motor pushed his son's "Starshooter" (an Estes Make It Take It) off the pad, after which Marc's scratch built orange "Razor" took to the blue on an A3-4T. Also scratch built, "Shockwave" was up next, grabbing some decent air on a B6. His last two flights were those of an Estes Screaming Mimi on a D12 (despite 4 noise makers, that rocket almost never makes any audible screams on the way up), and a very nice black Big Bertha powered by a C6-5. There were no recovery failures -  Marc and family retired from the field happy, with all models intact.

James' School Rocket lifts off (Click to enlarge).

Yellow Walmart scratch build gets going
(Click to enlarge).

James' Orange Walmart rocket starts its voyage on an E9 (Click to enlarge). 

One of the JPII team members, James, had three rockets to fly. The first was that of a Balsa Machining 3" School Rocket, which lifted off on an E9-4. Unfortunately, the orange model caught the Duane curse, and the upper motor tube centering ring pulled out of the model. The nose cone drifted gently to the ground, whereas the sustainer plummeted straight down, being saved from total obliteration only due to impacting into a pile of soft mulch by the road - very lucky. James also flew a couple of similar rockets (one orange and one yellow) made from body tubes and materials bought at a local Walmart. These put in very good performances on Estes E9's, deploying their homemade parachutes for safe landings. I must say that I was surprise by the fact that there was not a single CATO out of all those E motors flown on Saturday.

Vince's Quest Starfire on a B6 (Click to enlarge).

The A10 in the MoonGo ignites (Click to enlarge).

Vince gets the Enterprise ready for launch (Click to enlarge).

The Enterprise leaves the pad, with a clothespin caught in its tractor beam (Click to enlarge).

The Enterprise descends under its parachutes as Vince starts his recovery trek (Click to enlarge).

Vince also brought along a few rockets; a venerable Quest Starfire was first off the pad, riding the thrust of the popular B6-4 motor.  Next was the much anticipated flight of his Estes Starship Enterprise, the long "atmospheric probe" being painted to look like phaser beams. The Enterprise did not quite achieve warp on the C6-3, but the flight was very nice, with the parachute deploying to ensure a safe landing on the grass. An inspection of the pad showed that the motor's thrust had destroyed the clothespin used as a standoff, which I captured flying behind the model in a cell phone pic. His last flight was that of a Semroc MoonGo, which was up and gone on an A10-3T.

Methinks the rod needs adjusting, else the Airwalker
may stray far away  (Click to enlarge).

My Stellar Photon Probe looking all pretty before
launch (Click to enlarge).

Duane launches my Estes Asteroid Hunter (Click to enlarge).

And what did I fly, you may ask? I put three in the air, all powered by B6-4's - my Estes Airwalker,  my orange and white clone of the Centuri Stellar Photon Probe, and an obscure out-of-production Estes RTF - the Asteroid Hunter. Everything went well, including parachute deployments. I probably should have brought along a few more models, considering that the weather is going to be sucky cold for the foreseeable future, but I suppose that's why we have winter coats.

And that, good readers, is the short story of the two hour December 2nd launch at Pegasus field. Sunny, warm, and windless, we shall probably not see its like until Spring.