{
 "generated_utc": "2026-08-10T05:27:36Z",
 "gfs_cycle_utc": "2026-08-10T00:00:00Z",
 "model": {
  "source": "NCEP GFS 0.50 degree",
  "vertical_coordinate": "constant density (isopycnic)",
  "horizon_hours": 497.0,
  "output_interval_min": 30,
  "integration_step_s": 900,
  "wind_field_interval_h": 3
 },
 "staleness": {
  "fresh_seed_max_h": 24.0,
  "served_until_h": 336.0,
  "track_max_age_h": 72.0,
  "region_spread_deg": 60.0,
  "note": "A trajectory is served for 336 h after the last real fix and then the flight disappears. That matches the archive's own bridging limit: 23% of flights go quiet for over a week and are then heard again, so a shorter window drops balloons that are still flying. Past dead_reckoned flights the balloon has not been heard from since seed_time, so its present position is a prediction too -- the silent period is reconstructed from GFS analyses of weather that has already happened, which is why wind_source distinguishes analysis from forecast. Use display_as, not seed_age_h, to decide how to draw a flight: 'track' means the members still agree and a line is meaningful, 'region' means draw the member envelope instead because the nominal member is no better than any other."
 },
 "members": {
  "offsets_m": [
   -2000,
   -1500,
   -1000,
   -500,
   0,
   500,
   1000,
   1500,
   2000
  ],
  "nominal_offset_m": 0,
  "note": "Each member is seeded at the last observed altitude plus its offset and then conserves the density it started with. The ladder is a sensitivity fan, not a probability distribution: adjacent members diverge by roughly 1,200 km over seven days. levels_spanned reports how many GFS levels the fan actually straddles, usually 2 or 3."
 },
 "files": {
  "trajectories_csv_gz": "PBA_forecast_20260810_00Z.csv.gz",
  "trajectories_geojson_gz": "PBA_forecast_20260810_00Z.geojson.gz"
 },
 "counts": {
  "flights": 29,
  "members": 9,
  "rows": 140769
 },
 "flights": [
  {
   "callsign": "AG6NS-23",
   "flight_id": "AG6NS-23_2026-02-07",
   "payload_type": "WSPR",
   "seed_time": "2026-08-10 02:53:40",
   "seed_lat": -54.9375,
   "seed_lon": -164.20832,
   "seed_alt_m": 12540.0,
   "seed_age_h": 2.44,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-17 02:30:00",
    "lat": -42.03006,
    "lon": 77.37878,
    "alt_m": 12385.0
   },
   "member_spread_deg": {
    "lat": 29.73,
    "lon": 296.36
   },
   "member_spread_now_deg": {
    "lat": 0.73,
    "lon": 0.67
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "BSS53",
   "flight_id": "BSS53_2026-03-09",
   "payload_type": "WSPR",
   "seed_time": "2026-08-09 21:05:19",
   "seed_lat": 49.47917,
   "seed_lon": -40.5,
   "seed_alt_m": 12650.0,
   "seed_age_h": 8.25,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-16 23:30:00",
    "lat": 62.81985,
    "lon": 74.14689,
    "alt_m": 12776.6
   },
   "member_spread_deg": {
    "lat": 20.8,
    "lon": 59.38
   },
   "member_spread_now_deg": {
    "lat": 2.85,
    "lon": 7.37
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "BSS54",
   "flight_id": "BSS54_2026-07-09",
   "payload_type": "WSPR",
   "seed_time": "2026-08-10 04:38:19",
   "seed_lat": 46.25,
   "seed_lon": 91.375,
   "seed_alt_m": 14240.0,
   "seed_age_h": 0.7,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-17 04:15:00",
    "lat": 28.69222,
    "lon": 134.94456,
    "alt_m": 14576.4
   },
   "member_spread_deg": {
    "lat": 29.6,
    "lon": 331.95
   },
   "member_spread_now_deg": {
    "lat": 0.14,
    "lon": 0.36
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "DG2GG-23",
   "flight_id": "DG2GG-23_2026-05-23",
   "payload_type": "WSPR",
   "seed_time": "2026-08-09 21:09:00",
   "seed_lat": 42.33333,
   "seed_lon": -67.79167,
   "seed_alt_m": 12980.0,
   "seed_age_h": 8.18,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-16 23:45:00",
    "lat": 44.62641,
    "lon": 34.12441,
    "alt_m": 12695.2
   },
   "member_spread_deg": {
    "lat": 22.54,
    "lon": 166.13
   },
   "member_spread_now_deg": {
    "lat": 0.95,
    "lon": 2.11
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "DG2GG-27",
   "flight_id": "DG2GG-27_2026-07-04",
   "payload_type": "WSPR",
   "seed_time": "2026-08-10 00:18:00",
   "seed_lat": 17.10417,
   "seed_lon": -113.33333,
   "seed_alt_m": 14010.0,
   "seed_age_h": 5.03,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 1,
   "nominal_end": {
    "valid_time": "2026-08-16 23:45:00",
    "lat": -2.37708,
    "lon": -122.71583,
    "alt_m": 14040.2
   },
   "member_spread_deg": {
    "lat": 23.47,
    "lon": 48.85
   },
   "member_spread_now_deg": {
    "lat": 1.04,
    "lon": 1.31
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "DG2GG-29",
   "flight_id": "DG2GG-29_2026-07-28",
   "payload_type": "WSPR",
   "seed_time": "2026-08-04 04:57:00",
   "seed_lat": 46.91667,
   "seed_lon": 165.25,
   "seed_alt_m": 13380.0,
   "seed_age_h": 144.38,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-16 23:30:00",
    "lat": 31.13644,
    "lon": -22.22296,
    "alt_m": 13583.2
   },
   "member_spread_deg": {
    "lat": 74.74,
    "lon": 237.44
   },
   "member_spread_now_deg": {
    "lat": 48.06,
    "lon": 305.96
   },
   "display_as": "region",
   "display_reason": "member_spread"
  },
  {
   "callsign": "DJ2DS-34",
   "flight_id": "DJ2DS-34_2026-04-22",
   "payload_type": "WSPR",
   "seed_time": "2026-07-28 14:41:00",
   "seed_lat": 30.70833,
   "seed_lon": -70.5,
   "seed_alt_m": 9190.0,
   "seed_age_h": 302.65,
   "float_reliable": false,
   "dead_reckoned": true,
   "levels_spanned": 4,
   "nominal_end": {
    "valid_time": "2026-08-16 23:45:00",
    "lat": 18.4595,
    "lon": 107.43991,
    "alt_m": 9089.9
   },
   "member_spread_deg": {
    "lat": 47.49,
    "lon": 340.05
   },
   "member_spread_now_deg": {
    "lat": 43.03,
    "lon": 145.79
   },
   "display_as": "region",
   "display_reason": "member_spread"
  },
  {
   "callsign": "DL0MZ-493",
   "flight_id": "DL0MZ-493_2026-07-25",
   "payload_type": "WSPR",
   "seed_time": "2026-07-29 07:36:01",
   "seed_lat": 64.20833,
   "seed_lon": 58.16667,
   "seed_alt_m": 12170.0,
   "seed_age_h": 285.73,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 3,
   "nominal_end": {
    "valid_time": "2026-08-16 23:30:00",
    "lat": 68.93569,
    "lon": 47.30958,
    "alt_m": 11943.5
   },
   "member_spread_deg": {
    "lat": 61.64,
    "lon": 333.19
   },
   "member_spread_now_deg": {
    "lat": 43.23,
    "lon": 231.65
   },
   "display_as": "region",
   "display_reason": "member_spread"
  },
  {
   "callsign": "DL0MZ-493e",
   "flight_id": "DL0MZ-493e_2026-07-25",
   "payload_type": "WSPR",
   "seed_time": "2026-07-29 07:27:02",
   "seed_lat": 64.15625,
   "seed_lon": 58.08889,
   "seed_alt_m": 12170.0,
   "seed_age_h": 285.88,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 3,
   "nominal_end": {
    "valid_time": "2026-08-16 23:30:00",
    "lat": 34.51352,
    "lon": -38.81341,
    "alt_m": 12629.6
   },
   "member_spread_deg": {
    "lat": 51.2,
    "lon": 183.83
   },
   "member_spread_now_deg": {
    "lat": 36.75,
    "lon": 102.1
   },
   "display_as": "region",
   "display_reason": "member_spread"
  },
  {
   "callsign": "DN3LEO-13",
   "flight_id": "DN3LEO-13_2026-04-12",
   "payload_type": "WSPR",
   "seed_time": "2026-08-09 20:58:00",
   "seed_lat": 58.9375,
   "seed_lon": -41.125,
   "seed_alt_m": 12340.0,
   "seed_age_h": 8.37,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 3,
   "nominal_end": {
    "valid_time": "2026-08-16 23:30:00",
    "lat": 76.7114,
    "lon": -106.40257,
    "alt_m": 12079.0
   },
   "member_spread_deg": {
    "lat": 28.79,
    "lon": 283.32
   },
   "member_spread_now_deg": {
    "lat": 0.59,
    "lon": 3.35
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "EI6BFW-18",
   "flight_id": "EI6BFW-18_2026-07-25",
   "payload_type": "WSPR",
   "seed_time": "2026-08-10 00:43:00",
   "seed_lat": 69.25,
   "seed_lon": -116.95833,
   "seed_alt_m": 12677.0,
   "seed_age_h": 4.62,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-17 00:15:00",
    "lat": 69.0914,
    "lon": -85.63528,
    "alt_m": 12263.9
   },
   "member_spread_deg": {
    "lat": 13.29,
    "lon": 44.92
   },
   "member_spread_now_deg": {
    "lat": 1.88,
    "lon": 0.47
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "K5NOT-11",
   "flight_id": "K5NOT-11_2026-06-20",
   "payload_type": "WSPR",
   "seed_time": "2026-08-10 03:45:37",
   "seed_lat": 33.04161,
   "seed_lon": 175.83333,
   "seed_alt_m": 13420.0,
   "seed_age_h": 1.57,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-17 03:15:00",
    "lat": 32.66918,
    "lon": -118.13168,
    "alt_m": 13440.7
   },
   "member_spread_deg": {
    "lat": 39.11,
    "lon": 313.74
   },
   "member_spread_now_deg": {
    "lat": 0.58,
    "lon": 0.92
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "K9YO-23",
   "flight_id": "K9YO-23_2026-07-13",
   "payload_type": "WSPR",
   "seed_time": "2026-07-27 06:25:49",
   "seed_lat": 52.5833,
   "seed_lon": 125.16663,
   "seed_alt_m": 12840.0,
   "seed_age_h": 334.9,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-16 23:30:00",
    "lat": 43.44353,
    "lon": -72.32475,
    "alt_m": 13008.1
   },
   "member_spread_deg": {
    "lat": 56.82,
    "lon": 249.56
   },
   "member_spread_now_deg": {
    "lat": 63.31,
    "lon": 324.23
   },
   "display_as": "region",
   "display_reason": "member_spread"
  },
  {
   "callsign": "KC3LBR-449",
   "flight_id": "KC3LBR-449_2026-07-06",
   "payload_type": "WSPR",
   "seed_time": "2026-08-09 22:47:18",
   "seed_lat": 52.66667,
   "seed_lon": -45.625,
   "seed_alt_m": 13360.0,
   "seed_age_h": 6.55,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-16 23:45:00",
    "lat": 72.69829,
    "lon": 94.65109,
    "alt_m": 13506.1
   },
   "member_spread_deg": {
    "lat": 29.99,
    "lon": 48.06
   },
   "member_spread_now_deg": {
    "lat": 1.37,
    "lon": 2.12
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "KC3LBR-485",
   "flight_id": "KC3LBR-485_2026-03-19",
   "payload_type": "WSPR",
   "seed_time": "2026-07-28 09:08:18",
   "seed_lat": 50.14583,
   "seed_lon": 23.375,
   "seed_alt_m": 12850.0,
   "seed_age_h": 308.2,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-16 23:45:00",
    "lat": 65.28112,
    "lon": -2.61074,
    "alt_m": 12695.4
   },
   "member_spread_deg": {
    "lat": 38.66,
    "lon": 240.41
   },
   "member_spread_now_deg": {
    "lat": 31.57,
    "lon": 315.23
   },
   "display_as": "region",
   "display_reason": "member_spread"
  },
  {
   "callsign": "KC5TRB-1",
   "flight_id": "KC5TRB-1_2026-06-20",
   "payload_type": "WSPR",
   "seed_time": "2026-08-09 17:55:43",
   "seed_lat": 63.54161,
   "seed_lon": -33.7083,
   "seed_alt_m": 12600.0,
   "seed_age_h": 11.41,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-16 23:30:00",
    "lat": 56.84556,
    "lon": 64.22137,
    "alt_m": 12301.4
   },
   "member_spread_deg": {
    "lat": 26.6,
    "lon": 56.98
   },
   "member_spread_now_deg": {
    "lat": 0.51,
    "lon": 1.49
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "KD7FXO-1",
   "flight_id": "KD7FXO-1_2026-08-02",
   "payload_type": "WSPR",
   "seed_time": "2026-08-09 19:25:00",
   "seed_lat": 35.89583,
   "seed_lon": -28.16667,
   "seed_alt_m": 13120.0,
   "seed_age_h": 9.92,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-16 23:30:00",
    "lat": 41.66134,
    "lon": 34.19084,
    "alt_m": 12657.5
   },
   "member_spread_deg": {
    "lat": 16.1,
    "lon": 42.22
   },
   "member_spread_now_deg": {
    "lat": 1.12,
    "lon": 2.46
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "KE8RES-8",
   "flight_id": "KE8RES-8_2026-06-20",
   "payload_type": "WSPR",
   "seed_time": "2026-08-09 22:31:00",
   "seed_lat": 57.5625,
   "seed_lon": -97.66667,
   "seed_alt_m": 12060.0,
   "seed_age_h": 6.82,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 3,
   "nominal_end": {
    "valid_time": "2026-08-16 23:30:00",
    "lat": 70.14371,
    "lon": -48.46419,
    "alt_m": 12025.0
   },
   "member_spread_deg": {
    "lat": 11.58,
    "lon": 53.07
   },
   "member_spread_now_deg": {
    "lat": 0.77,
    "lon": 2.52
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "KE9DAB-11",
   "flight_id": "KE9DAB-11_2026-07-29",
   "payload_type": "WSPR",
   "seed_time": "2026-08-10 04:41:00",
   "seed_lat": 47.14583,
   "seed_lon": 64.08333,
   "seed_alt_m": 12170.0,
   "seed_age_h": 0.65,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 3,
   "nominal_end": {
    "valid_time": "2026-08-17 04:15:00",
    "lat": 44.28709,
    "lon": -161.04776,
    "alt_m": 12414.9
   },
   "member_spread_deg": {
    "lat": 29.75,
    "lon": 337.7
   },
   "member_spread_now_deg": {
    "lat": 0.08,
    "lon": 0.41
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "KI1TEN-1",
   "flight_id": "KI1TEN-1_2026-07-23",
   "payload_type": "WSPR",
   "seed_time": "2026-08-01 22:55:27",
   "seed_lat": 23.95828,
   "seed_lon": -104.12496,
   "seed_alt_m": 12380.0,
   "seed_age_h": 198.41,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 3,
   "nominal_end": {
    "valid_time": "2026-08-16 23:30:00",
    "lat": 5.19659,
    "lon": -101.6026,
    "alt_m": 12374.7
   },
   "member_spread_deg": {
    "lat": 20.58,
    "lon": 99.49
   },
   "member_spread_now_deg": {
    "lat": 18.92,
    "lon": 29.88
   },
   "display_as": "region",
   "display_reason": "seed_age"
  },
  {
   "callsign": "KI6DS-11",
   "flight_id": "KI6DS-11_2026-02-03",
   "payload_type": "WSPR",
   "seed_time": "2026-08-09 19:25:45",
   "seed_lat": 59.56245,
   "seed_lon": -24.12498,
   "seed_alt_m": 13390.0,
   "seed_age_h": 9.9,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-16 23:30:00",
    "lat": 64.34934,
    "lon": 125.16331,
    "alt_m": 13260.4
   },
   "member_spread_deg": {
    "lat": 26.02,
    "lon": 286.62
   },
   "member_spread_now_deg": {
    "lat": 3.58,
    "lon": 13.56
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "SP2ROC-41",
   "flight_id": "SP2ROC-41_2026-01-25",
   "payload_type": "WSPR",
   "seed_time": "2026-08-10 04:33:00",
   "seed_lat": 47.77083,
   "seed_lon": -179.45833,
   "seed_alt_m": 16040.0,
   "seed_age_h": 0.78,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 1,
   "nominal_end": {
    "valid_time": "2026-08-17 04:00:00",
    "lat": 39.95895,
    "lon": -162.8101,
    "alt_m": 16237.8
   },
   "member_spread_deg": {
    "lat": 45.22,
    "lon": 345.2
   },
   "member_spread_now_deg": {
    "lat": 0.38,
    "lon": 0.18
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "SP6MPL-34",
   "flight_id": "SP6MPL-34_2025-12-03",
   "payload_type": "WSPR",
   "seed_time": "2026-07-31 18:52:00",
   "seed_lat": 74.5625,
   "seed_lon": -160.0,
   "seed_alt_m": 12890.0,
   "seed_age_h": 226.47,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-16 23:45:00",
    "lat": 57.03181,
    "lon": -96.49485,
    "alt_m": 13142.0
   },
   "member_spread_deg": {
    "lat": 29.87,
    "lon": 278.6
   },
   "member_spread_now_deg": {
    "lat": 15.81,
    "lon": 324.61
   },
   "display_as": "region",
   "display_reason": "member_spread"
  },
  {
   "callsign": "SP6MPL-9",
   "flight_id": "SP6MPL-9_2026-08-02",
   "payload_type": "APRS",
   "seed_time": "2026-08-04 04:05:45",
   "seed_lat": 45.52942,
   "seed_lon": 75.286,
   "seed_alt_m": 12836.0,
   "seed_age_h": 145.24,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-16 23:30:00",
    "lat": 50.64239,
    "lon": 76.95749,
    "alt_m": 12503.2
   },
   "member_spread_deg": {
    "lat": 30.32,
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   },
   "member_spread_now_deg": {
    "lat": 23.97,
    "lon": 336.91
   },
   "display_as": "region",
   "display_reason": "member_spread"
  },
  {
   "callsign": "VE3VRO-36",
   "flight_id": "VE3VRO-36_2026-07-30",
   "payload_type": "WSPR",
   "seed_time": "2026-08-10 04:11:00",
   "seed_lat": 45.47917,
   "seed_lon": 96.54167,
   "seed_alt_m": 13170.0,
   "seed_age_h": 1.15,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-17 03:45:00",
    "lat": 18.71791,
    "lon": -169.32713,
    "alt_m": 13613.9
   },
   "member_spread_deg": {
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   },
   "member_spread_now_deg": {
    "lat": 0.36,
    "lon": 0.43
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "W0RBO-12",
   "flight_id": "W0RBO-12_2026-05-02",
   "payload_type": "WSPR",
   "seed_time": "2026-08-10 04:55:23",
   "seed_lat": 45.60411,
   "seed_lon": 69.87502,
   "seed_alt_m": 13480.0,
   "seed_age_h": 0.41,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-17 05:00:00",
    "lat": 50.15361,
    "lon": -122.65882,
    "alt_m": 13470.8
   },
   "member_spread_deg": {
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    "lon": 353.66
   },
   "member_spread_now_deg": {
    "lat": 0.1,
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   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "ZS6SRC-37",
   "flight_id": "ZS6SRC-37_2026-07-15",
   "payload_type": "WSPR",
   "seed_time": "2026-07-31 04:34:00",
   "seed_lat": -23.70833,
   "seed_lon": 149.29167,
   "seed_alt_m": 12380.0,
   "seed_age_h": 240.77,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 3,
   "nominal_end": {
    "valid_time": "2026-08-16 23:30:00",
    "lat": -2.39717,
    "lon": 27.2723,
    "alt_m": 12633.5
   },
   "member_spread_deg": {
    "lat": 41.66,
    "lon": 271.85
   },
   "member_spread_now_deg": {
    "lat": 19.47,
    "lon": 162.78
   },
   "display_as": "region",
   "display_reason": "member_spread"
  },
  {
   "callsign": "ZS6SRC-39",
   "flight_id": "ZS6SRC-39_2026-08-05",
   "payload_type": "WSPR",
   "seed_time": "2026-08-10 04:51:00",
   "seed_lat": -23.20833,
   "seed_lon": 113.0,
   "seed_alt_m": 15720.0,
   "seed_age_h": 0.48,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 1,
   "nominal_end": {
    "valid_time": "2026-08-17 04:15:00",
    "lat": -11.44123,
    "lon": -139.00317,
    "alt_m": 15844.5
   },
   "member_spread_deg": {
    "lat": 36.49,
    "lon": 300.18
   },
   "member_spread_now_deg": {
    "lat": 0.23,
    "lon": 0.57
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "ZS6SRC-84",
   "flight_id": "ZS6SRC-84_2026-07-12",
   "payload_type": "WSPR",
   "seed_time": "2026-07-27 15:20:00",
   "seed_lat": -7.75,
   "seed_lon": 8.375,
   "seed_alt_m": 13090.0,
   "seed_age_h": 326.0,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-16 23:45:00",
    "lat": 0.55242,
    "lon": -14.27625,
    "alt_m": 13155.1
   },
   "member_spread_deg": {
    "lat": 65.73,
    "lon": 180.61
   },
   "member_spread_now_deg": {
    "lat": 28.63,
    "lon": 273.63
   },
   "display_as": "region",
   "display_reason": "member_spread"
  }
 ]
}