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Well-Known Member
Jan 19, 2009
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This is the Readers Digest version of the LOC Viper III review (the full review with pictures will be up on EMRR soon):

The LOC Viper III is my third LOC kit and I purchased it for the 24mm x 3 cluster aspect. I wanted a cluster rocket that could fly on D12's and E9's and the Viper III fit the bill.

The Viper III is a 47.5" tall rocket based on a 2.6" airframe with the cluster of motor tubes sticking out of the bottom. The three fins are attached at the joints of the motor tubes. Nothing terribly fancy about the rocket.

As I said, this rocket is simple to build. Here's what you do:

* Glue Motor Tubes together
* Glue Centering Rings on Motor Tubes
* Glue Motor Tubes into Body Tube
* Glue on Fins
* Attach Shock Cord Mount
* Attach Shock Cord and Parachute
* Attach Nose Cone
* Finish

That is it, really!

LOC recommends three of the following motors: D12-5, D21-7, E9-6, E15-7, E30-10, and F21-8.

LOC indicates the rocket should weigh 16 ounces.

I added a piece of Nomex® heatshield and prepared for its first flight on D12-7's.

Using my Estes Command Controller on 14.4V all three motors ignited and lifted the Viper III to an excellent first flight. The flight was perfectly straight and it was a perfect apogee at ejection. Recovery was good with a fairly fast descent rate on the smaller parachute.

I felt the rocket would life fine on three C11-3's so I gave that a try. Unfortunately only two ignited and lifted the rocket to about 25 feet, it turned and then a few feet from the ground ejected. There was no damage.

The third flight was on three E9-6's. Varooom! This was great! Straight and good altitude. It was still heading up, but not at a fast pace when the ejection charge popped the parachute. The fast descent rate helps to keep it from drifting off.

What a nice flier on Estes motors! The descent rate is fast, but the rocket is sturdy and can take it.

The rocket is super simple to build. You can get away with wood glue (or Omni) except you should use epoxy for the shock cord mount. This is the type of rocket that can give the Estes-motor flier an entrance kit into LOC/Precision. That can be a stepping stone into mid to high power. Definitely a kit to consider.
nice paint job!

also one of my favorites,,I fly it atleast once at every launch
Ohh, I like your paint job better and your decal/lettering job.

It's a keeper, eh?


On the last flight of my ViperIII, the combined ejection charge blew a hole in the brand-new Nomex heat shield. Did you note any damage on yours?

No, but only using Estes motors. If you are using composites, they have a bigger punch. I'm only (3) flights on the Viper.
The Viper III is one of my favorite rockets, Nick. I fly it almost every time out now.

My standard engine combo these days is the E9-8, which makes for a really nice launch. To date I've flown it 9 times using the following combos...

(4x) E9-8
(2x) E30-7T
F12-5J (call me psycho)

Every flight has been great, although I had a separation on the maiden flight (Mar 00) on E30s. On the E9-6 flight only two motors lit and it still flew great. The F12 was done on a dare, with my 24mm casing plus two borrowed ones and some homemade igniters that were hot enough to light the Blackjack motors. That flight was an AWESOME one!

Built mostly stock. I added one of those brass bolt anchors between the three motor tubes during the build so I can use positive motor retention. Still in primer, a little worse for wear from 4+ years and one cross-country move, but still a FUN rocket.

A Viper IV is on my list...