11

Build your first rocket

FEATURE

ost model rockets follow the

basic flight process that’s been

unchanged since the Space Race.

A motor accelerates the rocket

upwards. At some point, the engine

stops burning – the rocket then

slows, and falls to earth. A parachute is deployed

and glides the craft down as safely as possible.

However, since SpaceX pioneered vertical landing

(where a second burn of the engines slows the

rocket down, allowing the rocket to land vertically

on the pad), hobbyist rocketeers have been keen

to emulate this feat.

Joe Barnard is attempting to do this using solid-

fuel rockets, and regularly uploading videos on his

progress to YouTube at: hsmag.cc/pZALEA. These

engines are cheap and simple to use, but don’t have

any control over the thrust. Once they’re lit, they

keep burning until they’re spent, unlike hybrid or liquid

engines that can vary their thrust. This means that it

has to be lit at exactly the right moment (or at least

within about 20 ms of the right moment) in order to

land smoothly.

PRACTICE MAKES PERFECT

“It’s not perfect, but as soon as you start adding

actual throttle control, everything gets about 1000

times harder because then you need plumbing, you

need much stricter safety procedures. If you’re willing

to accept that – just by luck – some of your flights

aren’t going to work, then you can get really close

with solids.”

While the amount of thrust can’t change, the

direction can. Joe developed a thrust vector control

system that can angle the motor in order to keep the

rocket upright as it takes off and returns to earth.

In order to simplify the problem, Joe’s currently

working on just the landing, by dropping rockets

from drones.

“I think I’m getting pretty close to getting it. I don’t

know if it’s going to be a couple more tests, or if it’s

going to be another three years. We’ll see.”

Joe’s work is unashamedly inspired by SpaceX.

In fact, Joe first started working on thrust vector in

order to hopefully impress SpaceX enough to get a job

there. He’s no longer working towards this aim, but

you can still see this inspiration in some of his rockets,

including the 1/48th scale model of a Falcon Heavy that

he’s working on, complete with thrust vectoring in the

boosters and second stage.

Looking to recreate Joe’s style of rocket? He sells

the Signal thrust vectoring system, which comprises

a flight computer and 3D-printed mount that uses two

9 g servos to control the motor. He’s also publishing a

series of videos, entitled ‘Landing Model Rockets’, that

go through the technicalities of doing exactly this.

M

Meet the maker attempting

to land model rockets

JOE BARNARD

Below

The electron rocket

that Joe’s been

attempting to land

vertically. Note that

the fins are on the

top to help stability

when coming down