Approach

Reliable. Valuable. Achievable.

Prismatic’s success with Unmanned Aerial Vehicles (UAVs) and small satellites has been achieved through the application of simple to understand – but demanding to pursue – principles for both the technical and management challenges. The Zephyr programme, set up by Paul Brooks, Jon Dixon, Darryl Sergison and Chris Kelleher in 2002 remains the only successful HALE UAV program to date. The challenges of persistent flight in the thin, cold stratospheric environment are therefore obviously demanding and there is no magic – so how did we succeed when everyone else (to date) has failed?

Technical

The technical principles can be summarised in two generic approaches, “Design for the operation. This means that the the system is designed for its nominal operating environment and the small periods of time when the environment is significantly different (launch and recovery) are events that need to be managed within the design, not designed for. This principle drives the necessary optimisation of mass and efficiency to enable such low power flight for long endurance.

“Design as a satellite.”

A second critical element to our success was the background of the team in satellites, specifically small satellites such as TopSat, STRV and TSX-5 (MWIR). The key point about satellites is that they have to operate in a very harsh environment for many years with no ability to repair or even see the satellite once it has been launched. This leads to a strict approach on design, qualification, acceptance and testing, which, with our significant experience, is well understood by Prismatic, was unknown to the aircraft industry that was developing other UAV systems. Over the years, Prismatic has enhanced this approach to include the essential requirements of aircraft design, build and operations that also allow UAVs to be accepted by the aviation authorities, a community that has an outstanding track record for air safety, proven over decades of manned flight.

Management

As important as the technical approach is the management. Jonathan Dixon and Paul Brooks started the Zephyr Programme with very clear views win how to manage difficult, technical developments based on over a decade of small satellite projects. Whilst this started with the simplest premise that the team needed to be a co-located, small incubator (the definition of incubator being – if you were inside you were not allowed out, and if you were outside you were not allowed in), the management principles have been extended over the years to a set of “Rules”. Embodied in the “Small book of Management”, these rules – with additions and adaptations – still apply to Prismatic’s activities today, noting that such rules have to conform to their own Rule 14 and the Pirates of the Caribbean – “It’s more what you would call guidelines than actual rules.”

Result

The result of Prismatic’s unique approach is clear as shown by this summary of UAV endurance and mass.   Longer duration and lower mass means lower through life costs.

Bringing COTS back to aerospace

One of the key benefits of combining our experience of satellites and UAVs has been the opportunity to utilise the best of both domains in terms of technology and approach. In addition to bring spacecraft approaches to UAVs to ensure reliable, long duration and extremely efficient operation, we are now bringing Commercial off the shelf (COTS) technologies from the UAV, power and mobile electronics industries back to the satellite field. The huge volumes associated with these markets lead to highly reliable and consistent devices that, when carefully managed for the same environment, provide much more capable systems.