Pascal Bonderer used to spend half a day on site every month, walking a 50-acre Swiss construction site with a GPS receiver, placing and measuring ground control points before and after each drone flight. The physical markers were the only way to get the accuracy his earthworks volumetrics required — and the most error-prone part of the whole workflow. Now he clicks a few inputs in WingtraCLOUD, flies a 40-minute mission, and gets the same number, without a single ground marker deployed.
In the Wingtra case study, Bonderer described the appeal plainly: the GCP workflow introduces variability — every time a different operator places targets, you get drift. SURVEY61 removes that entirely.
Wingtra, a Zurich-based drone company, announced the SURVEY61 sensor on February 12, 2026, alongside the WingtraRAY platform, a fixed-wing VTOL drone that takes off and lands vertically but flies like an airplane during the survey run. The combination is what Wingtra calls the first commercially viable, GCP-free surveying system at survey-grade accuracy — no pre-positioned ground markers, no post-flight GPS tie-in, just the drone, its onboard GNSS receiver, and cloud processing.
The technical foundation is PPK, or Post-Processed Kinematics. During flight, the SURVEY61's 61-megapixel full-frame sensor — a 35-millimeter low-distortion lens in nadir mount, per KorecGroup's technical breakdown — captures imagery while a GNSS receiver logs satellite position data at every shot. After landing, that data is processed against known base station positions in WingtraCLOUD to compute corrected camera positions — producing absolute accuracy of around 1 to 3 centimeters, Wingtra says. GCPs, in this workflow, become optional rather than mandatory.
The claim is technically credible rather than speculative. Bonderer's monthly survey data from the Sportwelt Gossau complex in St. Gallen, Switzerland — publicly visible on Wingtra's data portal — shows 1.1 centimeter per pixel ground sample distance and 1 centimeter absolute accuracy at a 90-meter flight height across 15.7 hectares. Those numbers were achieved without a single ground control point.
WingtraRAY's design matters here. Because it can hover and circle — unlike a pure fixed-wing drone — it handles active construction sites where a plane-style approach would be useless. It also carries FAA Category 3 parachute approval for operations over people, which Wingtra says clears it for flights without waiver paperwork across roughly 98 percent of U.S. land — per AmeriSurv, the only platform in its class with that designation. For U.S. commercial drone operators, the GCP problem is compounded by the regulatory one: operations over people require waivers that most operators simply avoid dealing with.
The efficiency numbers are Wingtra's own, and they know it. For a 50-acre site, fieldwork drops from four hours to 40 minutes, according to Wingtra's announcement on AmeriSurv. Labor cost per acre falls by roughly 60 percent. Repeat volumetric surveys show up to 70 percent fewer discrepancies — because the GCP-free workflow eliminates the variability introduced when different operators place ground targets inconsistently across visits. A 250-acre earthworks site needs about 10 minutes of airtime; WingtraCLOUD processes the data in around two hours.
Julian Surber, senior product manager at Wingtra, described the significance plainly in a press statement: "Until now, surveyors had to spend significant time setting up and measuring GCPs before every flight — a process that can introduce errors and requires multiple people on site. SURVEY61 changes the economics of survey-grade mapping by removing that step entirely."
Wingtra is not the only company chasing GCP-free surveying — DJI has offered PPK workflows for years, and competitors like senseFly have marketed similar approaches. What Wingtra appears to have refined is the integration: the sensor resolution, the platform's operational simplicity, and the end-to-end cloud pipeline that makes the workflow viable for a mid-size construction contractor doing monthly volumetric surveys rather than a specialist photogrammetrist running occasional high-precision campaigns.
The efficiency and accuracy claims are Wingtra's to prove over time. Bonderer's data is a validation data point, not an independent study. But for an industry where GCP setup has been a known bottleneck — eaten labor hours, introduced operator-dependent error, required specialized knowledge — solving it at the platform level is a genuine workflow change, even if the underlying GNSS technique is not new.
What matters for now is the person standing next to the drone. Bonderer's half-day on site is now 40 minutes. The markers are gone. The number is cleaner. That's not a revolution. It's a better Tuesday.
