VK-7 - Rocketarium

This is a flying semi-scale model of the Viking sounding rocket, which was developed by the US to provide a better vehicle than the German V2. In the 1950's, several of the Viking rockets were designed and flown by the US Navy. As part of a scientific mission, the Viking 7 climbed to 136 miles, and beat the altitude record of the V2. This rocket flies to more reasonable altitudes on a cluster of 2 model rocket motors. Try two B's for a smaller launch site, or go wild with two C motors. And if you are really brave, go for 2 x Klima D9...!

Multi-motor, or "cluster"
A "cluster" is a group of two or more motors, which are all ignited at the same time. The total thrust is the sum of the thrusts of each motor. Therefore, a group of small engines can lift a heavy rocket without the need to buy a larger engine.
Let's do some math: 2 B4-4 engines are equivalent to a C8 engine, 2 x B6-4 are equal to a C12, 2xC6-5 are the same of a D12.
Selecting different engine types allows you to fly in small fields, or send the model out of sight in a larger space.

Features:

• Over 73 cm Tall, 2-Motor Cluster Kit. Uses B, C or D9 Klima Motors, or Estes B and C.
• Comes with Ejection Baffle (no wadding required) and decals
• The kit includes illustrated instructions, motor mount kit with plywood cluster centering rings, body tubes, sturdy coupler, bands, nose cone, pre-cut basswood fins and 45 cm pre-assembled plastic parachute.
• There are three bands which go across the rocket's airframe to add detail to the model. Small rectangles glued on the fins, to add even more detail.
• Requires 5 mm Launch Rod, Intermediate Assembly Skills Required.

Some information on launching multi-engine models

To launch This rocket requires a launch pad and an electric launch controller, just like any other rocket model. But firing multiple motors at the same time is more difficult than firing a single motor. First, you need a launch controller with a battery that can supply a higher current than the usual 6 volt or 9 volt battery.
Then a 12 volt launch controller, such as the Aerotech Interlock Controller or the Estes PS II, is highly recommended, as you will be wiring three igniters in parallel. A parallel connection of three igniters requires three times the current of a single igniter. If the battery cannot supply enough current, only one motor may fire, and the rocket will follow an arcing trajectory that will almost certainly lead to a crash.

If you do not have a powerful battery or a suitable launch controller, you can use Tapematch and Stage Ignters, with just a low current starter, such as the Klima Igniter. Using this setup the ignition is perfect every time, even with the standard Estes launch controls. Read how to use the Tapematch and Stage Igniters on the respective product pages.