GeoEye’s 3D Airport Mapping for NGA Using Stereo Satellite Imagery

At the close of June, GeoEye revealed that it had secured another contract from the National Geospatial-Intelligence Agency (NGA). Unlike traditional imagery agreements, this contract focuses specifically on generating 3D datasets for airports worldwide. The announcement highlights a long-standing capability: through its acquisition of Space Imaging, GeoEye has been delivering similar 3D airfield products to NGA since 1999.

Stereo Satellite Imaging as the Foundation

According to Dejan Damjanovic, GeoEye’s program manager for airfield and harbor mapping, the key enabler of this capability lies in stereo satellite imagery. Satellites such as IKONOS—and previously OrbView-3—are able to capture stereo image pairs nearly simultaneously. Not all satellite systems offer this functionality.

Other sensors typically collect one image and then wait for a later orbital pass to acquire a second view of the same location. This time gap can introduce inconsistencies due to changing landscape features, shifting shadows, or cloud cover. IKONOS, by contrast, captures stereo pairs in rapid succession, preserving consistency and enhancing elevation accuracy.

Although the raw data returned from the satellite include elevation (Z) values associated with each pixel, further processing is required. For NGA, the deliverables must be formatted as 3D shapefiles and must comply with strict mapping standards established by NGA and international bodies such as ANSI, EUROCAE, and RTCA. Damjanovic participates in standards development, which he believes gives GeoEye a competitive advantage in meeting specification requirements.

For data extraction, GeoEye, NGA, and the Federal Aviation Administration (FAA) rely on BAE Systems’ Socet Set software, a photogrammetric tool widely used for stereo analysis and 3D modeling.

Enhancing Aviation Safety

The purpose of the 3D airport databases is straightforward: improving flight safety. Detailed terrain and obstacle information enables analysts to evaluate approach and departure paths with greater precision. Organizations such as FlightSafety use these datasets to construct flight simulators, allowing pilots to familiarize themselves with airport environments and potential hazards before operating there.

The broader initiative, known as the Stereo Airfield Collection program, traces its origins to a tragic event in 1996. U.S. Secretary of Commerce Ron Brown and several corporate executives were killed when their Air Force aircraft struck mountainous terrain during approach to Dubrovnik Airport in Croatia. The incident underscored the need for accurate, globally consistent 3D airfield data.

Prior to the commercialization of such efforts, similar products were derived from classified imagery. Today, commercial satellite providers collect stereo data and produce standardized 3D models for governmental use.

Why Not LiDAR?

High-resolution 3D data can also be collected using LiDAR technology. However, Damjanovic notes that the airports under NGA review are dispersed globally. While LiDAR resources are widely available in the United States, international coverage is far less consistent. Moreover, variations between LiDAR systems can produce datasets that differ in structure and quality, even when they meet technical requirements.

Using a single satellite sensor ensures that all airport models are generated from the same platform, enhancing uniformity and comparability across the global database.

Operational Scale and Workflow

Under the latest contract—its third for global 3D airport mapping—GeoEye is tasked with modeling 365 airports. IKONOS revisits the same geographic location approximately every three days, theoretically allowing each airport to be imaged multiple times annually. However, cloud cover limits the number of usable acquisitions.

To optimize collection efficiency, GeoEye applies a global cloud model to determine when imaging conditions are favorable. If clouds obscure a target location, the satellite may instead capture imagery of an alternate site. Typically, each airport can be successfully captured within a one- to two-month timeframe.

A team of approximately 15 to 20 specialists oversees the production of the 365 airport models, managing image acquisition, processing, quality control, and standards compliance.

Expanding Applications and Future Directions

Global air traffic growth is increasingly concentrated in developing regions. As passenger volumes rise, the demand for accurate 3D airfield mapping in these areas is expected to grow. Airports with heavier traffic may also require more frequent updates to maintain current hazard assessments.

Beyond aviation, similar 3D modeling techniques are finding applications in maritime environments. Ports and harbors—where navigation risks parallel those of aviation—represent another sector with growing demand for stereo-derived terrain and infrastructure models.

Additionally, stereo satellite imagery supports broader 3D modeling needs, including detailed representations of buildings and complex structures. While aviation safety remains a primary driver, the underlying technology enables diverse geospatial applications wherever accurate elevation and structural information are required.

In combining stereo satellite capabilities, standardized extraction workflows, and strict compliance with international mapping standards, GeoEye’s work for NGA demonstrates how commercial geospatial technology contributes directly to global transportation safety.