A Scottish aerospace start-up that goes by the name of Orbital Access, has recently unveiled plans to base it’s aircraft mothership at Malta’a Luqa airport.
Take a moment to process just how cool that sentence is.
By slinging the rocket under it’s carrier aircraft and flying it up to an altitude of around 40,000 feet, the entire first stage of launch, complete with a rocket engine and very heavy fuel can be totally eliminated from the equation, reducing costs significantly.
Although 40,000 feet, or 12km, might seem like a minuscule distance compared to the 2,000 kilometers of altitude satellites need to achieve a low earth orbit, 75% of the atmosphere’s mass is contained below this altitude, meaning that air resistance is greatly decreased once you get above this point.
Orbital Access plans to develop the system as a more cost effective competitor to a traditional rocket launch, where the entire flight is completed by the rocket itself.
Traditionally, rockets like this have tended to be staged, since the majority of weight in a rocket is the fuel to propel it. As this fuel burns, most of the rocket empties, adding extra weight. This is then jettisoned in a series of stages.
American aerospace company Orbital ATK already operates the similar Pegasus launch system, which has delivered 38 satellites to orbit, the last of which was in December 2016.
Additionally, having an aircraft to move your launch site around has more advantages: you can actively steer around weather, and as you get above the troposphere, the lowest portion of the atmosphere below which most of the earth’s weather occurs, this ceases to be a problem all together.
Citing the growing number of private space launches, company director Edmund Arcadian estimated that around 5,000 satellites a year globally could be launched in a few years. Citing the airport’s already existing infrastructural, and fairly long runway, around 1 flight per week is currently envisioned.
A typical sortie would most likely include a take off from Luqa, followed by an easterly route over either the Mediterranean or the Sahara desert – both of which are sparsely populated. An easterly launch direction is preferred because earth already rotates in this direction, giving the rocket a free boost. The Sahara is also close to the equator, which rotates a full 500km/h faster than the earth’s polar regions, meaning space companies will often try and choose equatorial launch sites – or with an air launch capability like this, equatorial adjacent.