Interim launch system

A comparative investigation of a ground and air launch of LEO-bound microsatellites

“…This launch option can be conducted worldwide although practically, some ground infrastructure and base is still needed which could potentially limit the inclination access and launch location; this is addressed in Section 4.3. In cases where a ground launch shares the launch site with other vehicles, an air launch mitigates this challenge as it can be operated independently of scheduling predicaments of such scenarios [Sarigul-Klijn, 2000]. In addition, an air launch could conceivably be conducted from any airport with appropriate runway length and propellant loading facilities, if needed, whereas this would not be possible for a ground launch even if the infrastructure was available given the associated noise and sonic boom [Donahue, 2004].…”

“…Payload mass difference % 448.6 43.1 Although the case herein was based on existing rocket motors with a prescribed structural mass, the effect described above increases the design safety margin instead of introducing design flexibility [Bonometti, 2006]. Moreover, given the simplified abort modes inherent to an air launch as further discussed in Section 4.11, an air launch system mitigates the relatively high abort loads which increase a vehicle's structural mass [Sarigul-Klijn, 2000].…”

“…According to [Sarigul-Klijn, 2000], infant mortality is a major contributor to launch vehicle failures. Since the highest probability of failure is at first use, warranties typically accompany new products due to infant mortality.…”

“…Since the highest probability of failure is at first use, warranties typically accompany new products due to infant mortality. As a result, this promotes a reusable system to minimize such failure sources and in turn provides the opportunity for incremental testing to further mitigate failures, improve safety and ultimately reduce insurance costs [Sarigul-Klijn, 2000]. Although the air launched alternative is not fully reusable, the carrier aircraft's reusability has the potential to deliver the benefits enumerated above.…”

“…Since the carrier aircraft can commute to the desired launch position, this introduces the opportunity to reach any orbital inclination such as that of the ISS without a plane change, eliminates waiting time for the desired orbital plane to pass above the ground launch site and enables one orbit rendezvous. As a result, for human missions, crews spend less time in the launch vehicle, approximately 1.5 hours, which reduces electrical power along with environment control and life support system requirements and in turn, maximizes payload mass [Sarigul-Klijn, 2000]. Ultimately, an air launch exhibits fewer delays since specific launch windows can be accessed directly, thereby minimizing waiting time [Sarigul-Klijn, 2006].…”