Birdi vs Propeller for Mining and Quarry Sites (2026)

TL;DR: Birdi (birdi.io) and Propeller both measure stockpiles and compare surveys on mine and quarry sites. Propeller is built around earthworks, with its own ground control hardware, machine telematics and mine planning exports. Birdi is built around getting the survey number, the imagery and the prism data to everyone who needs them, in one shared map.

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Key takeaways

• Accuracy comes from ground control, not the brand. Birdi publishes 2 to 4 cm vertical accuracy with RTK and well-distributed ground control, and Propeller says its PPK workflow can reach 3 cm with its recommended equipment.
• Consistency matters as much as accuracy. In Propeller's own test of 20 measurements of one stockpile, results varied 2.3% on average, falling to 0.8% when boundaries were drawn the same way each time.
• Tonnage carries a second error. According to Birdi's help center, a density of 1.6 against 1.8 t/m³ is a 12% swing in tonnes. The density you use matters as much as the volume.
• Drones are accurate enough for stockpiles. According to a 2022 study at a quarry in Malawi, a drone survey came within 2.6% of a stockpile's true volume. It also took 64% less time than a tape survey.
• Propeller has the stronger reviews and hardware. It holds 4.8 from 20 reviews on Capterra, and its AeroPoints and DirtMate cover ground control and haul fleets.

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What is the difference between Birdi and Propeller?

Propeller is a specialist earthworks and mining platform, with its own ground control hardware, PPK, fleet telematics and mine planning exports. Birdi is a shared geospatial workspace. It offers the same stockpile volumes and survey comparisons, plus 360 photos, prism points and documents in one map for engineers, finance and consultants. Both process in the cloud.

So the question is less "which measures better" and more "who needs the number". A survey team running daily reconciliation against the fleet leans Propeller. A site where the survey result has to reach a quarry manager, an accountant, a tailings consultant and an auditor leans Birdi. Every fact below was checked on each vendor's own site or help center on September 24, 2026.

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How do Birdi and Propeller compare, row by row?

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Which is more accurate for stockpile volumes?

Neither is inherently more accurate. Both reach centimeter-level results with good ground control, and both say so. Birdi publishes 2 to 4 cm vertical accuracy with RTK and three to five well-distributed ground control points. Propeller says its PPK workflow with recommended equipment can reach 3 cm. The capture method, not the platform, sets the limit.

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What each vendor publishes

Birdi publishes a full table by capture method. With standard GPS and no ground control, it expects 5 to 15 cm. It calls that "not appropriate for elevation or volume analysis." With RTK alone, it expects 3 to 8 cm, and a difference of up to 10 to 15 cm between two RTK-only surveys is "considered normal." With RTK and well-distributed ground control, both accuracy and repeatability improve to about 2 to 5 cm. For the detail, see our guide to drone data accuracy.

Propeller builds its accuracy around hardware. Its AeroPoints are smart ground control points with dual-frequency GNSS, and its PPK workflow corrects the drone's own positions. In addition, Propeller publishes a useful consistency test: 20 measurements of the same stockpile varied 2.3% on average, and 0.8% when boundaries were drawn tightly every time.

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What the independent evidence says

The research supports both approaches. According to a 2018 study in Remote Sensing, accuracy improves as ground control points increase and are spread evenly, across 3,465 combinations tested on a 1,200-hectare site. According to a 2022 study at Njuli quarry in Malawi, a drone survey measured a stockpile within 2.6% of its true volume, inside the ±3% the authors treat as acceptable. It also took 35 minutes against 97 for a tape survey.

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Why tonnage needs its own check

Tonnage multiplies the volume by a density, so it carries two errors. Birdi's help center gives the example: a density of 1.6 against 1.8 t/m³ is a 12% swing. For monitoring, a library density is fine. For an invoice, a royalty return or a haulage contract, both vendors let you enter a density measured from your own material.

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How does each compare stockpiles between surveys?

Both compare two surveys directly. In Birdi, you set the earlier survey's elevation model as the base on the latest map. The volume then measures what moved between flights, in cubic meters and tonnes. In Propeller, a cut and fill measurement compares the selected survey with the previous one, or with the design.

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In Birdi

Birdi calls this the Base DEM method. You reuse the same polygon from the earlier survey, set the earlier surface as the base, and calculate. The result reads as cut, fill and net volume between the two flights, and assigning a material adds tonnes. The table view exports it as a CSV or a branded PDF. Recalculating overwrites the previous result, so Birdi advises exporting after each survey to build a history. For the whole site, a difference grid colors every change in elevation between two surfaces, on Growth and Ultimate. Our guide to reconciling stockpile volumes walks through the monthly routine.

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In Propeller

Propeller's surface comparison tool covers cut and fill from the previous survey, cut and fill to design, bench volumes and area progress. Its mining page describes daily reconciliation, AI-assisted stockpile detection and a shrink and swell calculator. With DirtMate on the haul fleet, measurements can use predefined timeframes such as today or last week.

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Getting a comparison you can trust

The rule is the same on both platforms: use the same ground control on every survey. Birdi stores a site's GCPs as a reference set, versioned each time you re-survey, and carries it into every new map of that site. Propeller's AeroPoints do the same job as hardware. See our guide to ground control and volumetric reporting.

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Which is better for tailings and slope monitoring?

It depends on what you monitor. Propeller's mining tools include tailings storage facility fill rate tracking and slope gradient maps for audits. Birdi, on its Ultimate plan, stores prism reference sets against the site and shows each prism with its status. Difference grids then show movement between surveys.

In Birdi, a prism set is uploaded from a CSV template and kept as versions, one per re-survey. Each point carries a status of active, warning, destroyed or planned, and a change of status shows on every map of that site. Stacking two difference grids shows whether movement is speeding up or slowing down. These are tools for the engineer doing the assessment, not an automatic alert, and the tailings consultant still makes the call. For the wider context, see our explainer on tailings dam monitoring.

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What do Propeller users say?

Propeller's public reviews are strongly positive. It holds 4.8 from 20 reviews on Capterra, and 11 of the 20 praise its ease of use. Complaints are scattered rather than repeated: 3 of 20 mention navigation or interface friction, and 2 mention processing time or crashes. G2's summary lists cost as a complaint.

One 2025 reviewer wrote: "We use Propeller Aero on a daily basis. All aspects of our company use the portal." Another, in 2024, found the interface "can be intimidating" at first. The pool is small, so read these as individual experiences rather than a verdict.

Birdi has 5 reviews on Capterra, all rated 5, which is too few to show a pattern. The complaints that appear are small bugs when switching between 2D, 3D and media views, and a wish for more drone-specific algorithms. We could not read Reddit or G2's full review pages for this comparison.

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When should you choose Propeller, and when Birdi?

Choose Propeller when the survey team owns the workflow and the job is earthworks: daily reconciliation, ground control hardware, haul fleet data and exports to mine planning software. Choose Birdi when the number has to reach people outside the survey team, such as finance, operations, consultants and auditors, alongside imagery, 360 photos and prism data in one map.

In more detail:

• Survey-led quarry or mine running daily volumes against the fleet: Propeller.
• Site that wants ground control hardware in the box: Propeller, with AeroPoints.
• Monthly production reporting shared with finance and operations: Birdi, with the Base DEM comparison and a tonnage export.
• Tailings and embankment monitoring alongside site imagery: Birdi, with prism reference sets on Ultimate.
• Australian site with no drone capacity of its own: Birdi's capture network, for Ultimate customers in Australia, paid per capture.

Many sites could run both: Propeller for the survey team, and a shared map for everyone else. For how Birdi approaches mine sites, see Birdi for mining and resources.

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Frequently asked questions

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How accurate is Propeller for stockpiles?

Propeller says its PPK workflow with recommended equipment can reach 3 cm accuracy. In its own test, 20 measurements of one stockpile varied 2.3% on average, falling to 0.8% when boundaries were drawn tightly each time. Accuracy depends mainly on ground control and on measuring the same way on every survey.

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Do I need AeroPoints to use Propeller?

No. Propeller also imports surveys processed elsewhere, through its Bring Your Own Data credits. AeroPoints are its own smart ground control points, built to simplify survey-grade control. Standalone users pay an annual AeroPoints processing subscription of $999 per group, which is included with a platform or PPK license.

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Can Birdi calculate stockpile tonnage?

Yes. After Birdi calculates a volume, you assign a material from its library, or enter your own density, and tonnage appears beside the cubic meters. It works on single stockpiles, on several at once, and on AI-detected stockpiles. For invoices or royalties, Birdi recommends a density measured from your own material.

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Which is better for quarries, Propeller or Birdi?

Propeller is the stronger fit for a survey-led quarry that runs daily volumes, uses its ground control hardware and tracks the haul fleet. Birdi is the stronger fit where production numbers, imagery and prism data have to reach managers, finance, consultants and auditors who never open survey software.

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Can I compare two drone surveys to measure material moved?

Yes, on both. In Birdi, you set an earlier survey's elevation model as the base surface and measure the change, in cubic meters and tonnes. In Propeller, a cut and fill measurement compares a survey with the previous one or with the design. Use the same ground control on both surveys, or the difference includes survey noise.

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About the author

This comparison was written by the Birdi team. Birdi (birdi.io) is a geospatial AI workspace that mining, quarry and construction teams use to share survey results, drone imagery and monitoring data in one map. We checked every product fact against each vendor's own site or help center on September 24, 2026, and counted the reviews ourselves.

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Related reading

• Stockpile volume software compared: the wider set of stockpile platforms.
• Four platforms compared: Propeller, DroneDeploy, Pix4D and Birdi head to head.
• Propeller alternatives: other options for teams weighing Propeller.
• Tailings dam monitoring software: platforms for monitoring tailings storage.

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Sources

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Research and standards

1. Sanz-Ablanedo, E., Chandler, J.H., Rodríguez-Pérez, J.R. and Ordóñez, C. "Accuracy of Unmanned Aerial Vehicle (UAV) and SfM Photogrammetry Survey as a Function of the Number and Location of Ground Control Points Used." Remote Sensing 10(10), 1606, 2018. https://doi.org/10.3390/rs10101606
2. Matsimbe, J., Mdolo, W., Kapachika, C., Musonda, I. and Dinka, M. "Comparative utilization of drone technology vs. traditional methods in open pit stockpile volumetric computation: A case of Njuli Quarry, Malawi." Frontiers in Built Environment, November 3, 2022. https://doi.org/10.3389/fbuil.2022.1037487
3. Abdullah, Qassim A. "The ASPRS Positional Accuracy Standards, Edition 2." LIDAR Magazine, October 6, 2023. https://lidarmag.com/2023/10/06/the-asprs-positional-accuracy-standards-edition-2/

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Birdi

4. Birdi. "Pricing." Checked September 24, 2026. https://www.birdi.io/pricing
5. Birdi Help Center. "How accurate are my maps?"; "How to use the volumetric calculator"; "How accurate is the volumetric calculator?"; "How to compare stockpile volumes between two surveys"; "Difference grids"; "How to use Sites"; "How to upload GCP and prism reference sets"; "Working with reference points"; "Stockpile AI Detect to a volumetric report"; "User seats, roles and permissions." https://help.birdi.io/en/articles/13837409 · /10416417 · /10504763 · /16591511 · /16726906 · /16767430 · /16768238 · /16768386 · /13456551 · /11091551

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Propeller

6. Propeller. "Mining," "AeroPoints" and "Propeller PPK." Checked September 21 and 24, 2026. https://www.propelleraero.com/mining/ · https://www.propelleraero.com/aeropoints/ · https://www.propelleraero.com/propeller-ppk/
7. Propeller Help Center. "How to Get Consistent Stockpile Measurements" (August 6, 2026); "Surface comparisons and volume measurements in Propeller" (May 28, 2026); "Measuring Stockpiles: The Basics" (February 24, 2026); "How To Share and Manage Access To a Site" (July 9, 2026); AeroPoints subscription (July 29, 2026). https://help.propelleraero.com/hc/en-us/articles/19384273061399 · /19384053844631 · /19383873966487 · /19384064976407 · /19383553319703

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Reviews

8. Capterra. Propeller Aero (20 reviews) and Birdi (5). Read September 21, 2026. https://www.capterra.com/p/179319/Propeller-Platform/reviews/ · https://www.capterra.com/p/10026509/Birdi/reviews/
9. G2. Review summary for Propeller Aero (search snippet only). Read September 21, 2026. https://www.g2.com/products/propeller-aero/reviews

Review counts are small. Reddit, G2's full review pages and TrustRadius could not be read for this comparison.