SolarStratos reaches 24,500 feet during its flight campaign: promising results, with significant improvements to come
SolarStratos’s latest flight campaign from Payerne stands as a compelling demonstration of the aircraft’s maturity. Better than expected in terms of energy performance, rich in technical and regulatory validations, it paves the way for a series of developments that could push the boundaries of the solar aircraft even further. Here is the assessment, and what lies ahead.
Efficiency above expectations
The SolarStratos team has just wrapped up another remarkable flight campaign from Payerne. The headline result: 24,500 feet reached, and this with batteries at the end of their life. Even better, actual energy consumption proved to be lower than what the SolarStratos team had anticipated, which is a very encouraging sign regarding the overall efficiency of the aircraft.
Understanding the performance: two avenues being explored
To confirm and understand this performance, two avenues are being explored. The first is to entrust the batteries to a partner engineering school in order to precisely measure their residual State of Health (SOH). The second: a new flight campaign planned before the summer, during which the aircraft will perform full discharge and recharge cycles — batteries fully depleted, then fully recharged using chargers where the charging energy will be precisely measured. The goal: to understand exactly what goes in and out of the batteries, and to validate the hypothesis of better-than-expected efficiency.
2,500 more feet in sight
On the technical side, the campaign was also an opportunity to validate a long-awaited development: the airbrake. The team is pleased with it; all that remains is to paint it. Several aerodynamic optimizations have also been identified for the coming months: landing gear fairing, work on the tail wheel drag, work under the ailerons, and integration of the GoPro cameras into the fairing. Modest in appearance, these adjustments hold significant potential: up to 10% additional efficiency for the same energy, equivalent to about 2,500 extra feet. A dedicated performance campaign will then be organized to precisely measure the gains in climb rate.
Regulatory green light: FOCA validates the inspection
Another piece of good news: FOCA has validated its regulatory inspection.
Next campaign: two-seater configuration, Starlink tests and telemetry on the agenda
The next flight campaign promises to be busy. On the agenda: first two-seater flight with Olivier de Sybourg, Director of Operations, to validate the dual controls, new Starlink link tests, telemetry tests, and assessment of the robustness of communications under degraded conditions (5G loss, Starlink loss).
THA Project
And beyond that, the project that now crystallizes the team’s ambitions: THA — Très Haute Altitude (Very High Altitude). The goal is to demonstrate that it is possible to operate in the stratosphere safely, initially without a pressurized suit, in order to precisely establish the physiological limits of very high-altitude flight. This project will be led by the SolarStratos expedition physician, Professor Patrick Schoetker.
One step at a time, but every step resolutely upward.
Post of the month – First flight of the year
Discover in pictures the first flight of the HB-SXA this year. Click on this link !
