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Virgin Galactic 02

As I watched the livestream of Virgin Galactic's second commercial flight on YouTube, I couldn't help but wonder what its passengers were seeing out of the windows...

Looking at the Data

After the flight concluded, I looked up its track log on FlightAware, curious to see how the unusual altitudes would be represented. Not too surprisingly, altitudes above controlled airspace (i.e., above 60,000' - FL600, the "cieling" of "Class A" airspace - where no clear standard exists for reporting altitudes AFAIK) were just reported as 0 - i.e., missing values.

This was pretty clearly represented on their Altitude vs. Speed summary chart:

AeroAPI Altitude vs. Speed Summary

Another quickly evident "feature" of the track logs is that it doesn't capture True Air Speed (TAS), only "Groundspeed". Even though SpaceShipTwo was traveling at Mach 3 (through the atmosphere), over the ground she was going pretty slowly...

Creating the Visualization

Because it was easy to find SpaceShipTwo's "N" (aka "tail") number, being clearly visible in the livestream and elsewhere across the Internet, formulating the flightvisualizer command was a nobrainer.

I opted to use the --saveArtifacts option since I realized (see above) that I'd need to manually insert (a guess at) those missing altitudes above FL600 which weren't available in FlightAware's response, in an intermediary step:

$ fviz tracks --saveArtifacts --flightCount 1 \
  --tailNumber N202VG --cutoffTime 2023-08-10T10:00:00-06:00

See the zero altitudes:

$ cat fvt_VGX3-1691670738-sw-1757p.json | jq -c ".positions[] | {altitude: .altitude, timestamp: .timestamp}" | more
...
{"altitude":448,"timestamp":"2023-08-10T15:17:07Z"}
{"altitude":0,"timestamp":"2023-08-10T15:19:17Z"}
{"altitude":0,"timestamp":"2023-08-10T15:19:33Z"}
{"altitude":0,"timestamp":"2023-08-10T15:19:51Z"}
{"altitude":0,"timestamp":"2023-08-10T15:20:09Z"}
{"altitude":0,"timestamp":"2023-08-10T15:20:26Z"}
{"altitude":0,"timestamp":"2023-08-10T15:20:44Z"}
{"altitude":0,"timestamp":"2023-08-10T15:21:00Z"}
{"altitude":0,"timestamp":"2023-08-10T15:21:17Z"}
{"altitude":620,"timestamp":"2023-08-10T15:22:18Z"}
...

After replacing the 0 values with those from an approximation of a parabolic trajectory of the flight, confirming:

$ cat fvt_VGX3-1691670738-sw-1757p-withascent.json | jq -c ".positions[] | {altitude: .altitude, timestamp: .timestamp}" | more
...
{"altitude":448,"timestamp":"2023-08-10T15:17:07Z"}
{"altitude":1500,"timestamp":"2023-08-10T15:19:17Z"}
{"altitude":2350,"timestamp":"2023-08-10T15:19:33Z"}
{"altitude":2736,"timestamp":"2023-08-10T15:19:51Z"}
{"altitude":2858,"timestamp":"2023-08-10T15:20:09Z"}
{"altitude":2749,"timestamp":"2023-08-10T15:20:26Z"}
{"altitude":2590,"timestamp":"2023-08-10T15:20:44Z"}
{"altitude":2037,"timestamp":"2023-08-10T15:21:00Z"}
{"altitude":1218,"timestamp":"2023-08-10T15:21:17Z"}
{"altitude":620,"timestamp":"2023-08-10T15:22:18Z"}
...

Launch the Visualization in Google Earth

Once the manual "fixup" of the AeroAPI track log was ready, the visualization could be created & launched into Google Earth.

See this for yourself!

  • In order to "see" this visualization for yourself - even without running the flightvisualizer commands described below - just "drag & drop" file named fvk_N202VG_230810143103Z-53328Z_camera-path-vector-withascent.kmz from the artifacts folder into a running Google Earth on Desktop!
$ fviz tracks --launch --layers camera,path,vector \
  --fromArtifacts fvt_VGX3-1691670738-sw-1757p-withascent.json

Here are some screenshots I took during my visualization:

Shape of the Path

It was pretty amazing to see the "shape" of the flight path with the "Path Track" enabled:

Shape of the Path

View From The Top

Using the Google Earth controls to look around while "flying" the flight path from a first-person perspective (after clicking on "Camera View") gave me a good idea of what the passengers might have seen from their windows:

View From The Apogee

Though the view from the apogee didn't match my expectations of "what Earth should look like from space," it certainly was high up enough to give me pause - especially when I imagine being physically there - and to end any question I might have had about the Earth's being flat! ;-)