Thursday, January 7, 2016

My First High Power Rocket

I've just purchased my first true high power rocket kit: the Aerobee 150A, by Mad Cow Rocketry, from

My Estes Pro Series II rockets could technically be flown as high power rockets. Their 29mm motor mounts would allow me to install a small H motor. But they are generally considered mid power "model" rockets.

The Aerobee 150A has a 38mm motor mount - a high power mount. At 38mm, there is a wide selection of motors you can use to fly to different altitudes, and with a motor adapter, you can still use the smaller 29mm motors.

JonRocket only had one left in stock, and since I've been shopping there for over a year, I've accrued a lot of rewards points. When you buy from JonRocket, you get some points with every purchase, and each point is worth one dollar toward future purchases.

I only recently found this out - so I got this large kit, which normally sells for nearly $70, for only 18 bucks! Too good to pass up.

The Aerobee 150A was a NASA sounding rocket from the 1960s, and was part of the whole Aerobee "family" of sounding rockets.

The Aeorbee 150 sounding rocket - different from the Aerobee 150A rocket (see below)

Mad Cow has a great reputation for good quality kits. I won't be able to fly this rocket until I get a Level 1 high power certification. But I want to set this aside and do a little homework before I build it.

Here's another article from a 1997 edition of High Power Rocketry magazine on the Aerobee family of rockets. The 150A (which was similar to the 150, but with four fins instead of three) has its own section. Finding scale data on historic rockets can sometimes be difficult. I'd like to see what I can find out about what colors this rocket was before I build.

I also need to do some research on what's called dual deployment, a method in HPR of deploying the recovery system using altimeters rather than just an ejection charge in the rocket motor. Instead of simply having one big parachute come out when the rocket is at apogee, and instead of relying on an ejection charge built into the rocket motor as with model rocketry, in dual deployment, there are two ejection charges, controlled by an electronic, barometric altimeter. The first charge fires at apogee - the highest point in the rocket's flight - and the rocket descends on a small drogue parachute. This stabilizes the rocket's descent, and brings it down quickly to a lower altitude. But that's not really enough for a soft landing.

At a lower altitude, the altimeter causes a second ejection charge to fire, which deploys the main parachute. This chute is large enough to bring the rocket down to a soft touchdown.

A diagram of the flight events in a dual deployment rocket. From

The main reason for dual deployment is to keep the rocket from drifting too far for successful recovery. If it came down on one big chute from apogee, like a small model rocket, a high-flying, high power rocket might drift very, very far.

Also, some rocketeers like the added complexity of building a system with two events. And, of course, the altimeter will tell you how high the rocket flew, once you recover it.

I understand the basics, but have never tried it myself, so I've got some homework to do. In the mean time, I have tons of low and mid power rockets to finish building.

In any case, I'm pretty excited to have this large rocket on its way to my house.

Like my Facebook page for blog updates and extra stuff.

No comments:

Post a Comment