{
 "generated_utc": "2026-07-27T17:24:57Z",
 "gfs_cycle_utc": "2026-07-27T12:00:00Z",
 "model": {
  "source": "NCEP GFS 0.50 degree",
  "vertical_coordinate": "constant density (isopycnic)",
  "horizon_hours": 168.0,
  "output_interval_min": 30,
  "integration_step_s": 900,
  "wind_field_interval_h": 3
 },
 "staleness": {
  "fresh_seed_max_h": 24.0,
  "served_until_h": 168.0,
  "note": "A trajectory is served for seven days after the last real fix and then the flight disappears. 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."
 },
 "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_20260727_12Z.csv.gz",
  "trajectories_geojson_gz": "PBA_forecast_20260727_12Z.geojson.gz"
 },
 "counts": {
  "flights": 34,
  "members": 9,
  "rows": 102870
 },
 "flights": [
  {
   "callsign": "AG6NS-23",
   "flight_id": "AG6NS-23_2026-02-07",
   "payload_type": "WSPR",
   "seed_time": "2026-07-27 15:38:40",
   "seed_lat": -56.95834,
   "seed_lon": -9.49999,
   "seed_alt_m": 12360.0,
   "seed_age_h": 1.69,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 3,
   "nominal_end": {
    "valid_time": "2026-08-03 15:15:00",
    "lat": -47.38979,
    "lon": -79.21117,
    "alt_m": 12432.8
   },
   "member_spread_deg": {
    "lat": 30.17,
    "lon": 75.87
   }
  },
  {
   "callsign": "BSS52",
   "flight_id": "BSS52_2025-12-25",
   "payload_type": "WSPR",
   "seed_time": "2026-07-24 17:39:48",
   "seed_lat": 59.97917,
   "seed_lon": 4.08333,
   "seed_alt_m": 13000.0,
   "seed_age_h": 71.67,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-07-31 17:15:00",
    "lat": 70.5275,
    "lon": 155.22255,
    "alt_m": 12704.1
   },
   "member_spread_deg": {
    "lat": 18.02,
    "lon": 70.48
   }
  },
  {
   "callsign": "BSS53",
   "flight_id": "BSS53_2026-03-09",
   "payload_type": "WSPR",
   "seed_time": "2026-07-27 16:51:18",
   "seed_lat": 44.9375,
   "seed_lon": -27.875,
   "seed_alt_m": 12960.0,
   "seed_age_h": 0.48,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-03 16:15:00",
    "lat": 65.78237,
    "lon": 176.63276,
    "alt_m": 12848.5
   },
   "member_spread_deg": {
    "lat": 20.46,
    "lon": 110.25
   }
  },
  {
   "callsign": "BSS54",
   "flight_id": "BSS54_2026-07-09",
   "payload_type": "WSPR",
   "seed_time": "2026-07-27 17:02:48",
   "seed_lat": 44.75,
   "seed_lon": -124.16667,
   "seed_alt_m": 14060.0,
   "seed_age_h": 0.29,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 1,
   "nominal_end": {
    "valid_time": "2026-08-03 17:00:00",
    "lat": 31.28592,
    "lon": -45.87548,
    "alt_m": 14532.4
   },
   "member_spread_deg": {
    "lat": 28.05,
    "lon": 167.57
   }
  },
  {
   "callsign": "DG2GG-23",
   "flight_id": "DG2GG-23_2026-05-23",
   "payload_type": "WSPR",
   "seed_time": "2026-07-27 04:09:00",
   "seed_lat": 52.16667,
   "seed_lon": -169.125,
   "seed_alt_m": 13020.0,
   "seed_age_h": 13.18,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-03 03:45:00",
    "lat": 27.09045,
    "lon": -99.7656,
    "alt_m": 13159.8
   },
   "member_spread_deg": {
    "lat": 15.62,
    "lon": 350.14
   }
  },
  {
   "callsign": "DG2GG-25",
   "flight_id": "DG2GG-25_2026-06-15",
   "payload_type": "WSPR",
   "seed_time": "2026-07-25 07:22:00",
   "seed_lat": 68.97917,
   "seed_lon": 68.16667,
   "seed_alt_m": 12990.0,
   "seed_age_h": 57.97,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-01 06:45:00",
    "lat": 76.68181,
    "lon": -109.53647,
    "alt_m": 12759.5
   },
   "member_spread_deg": {
    "lat": 32.54,
    "lon": 82.79
   }
  },
  {
   "callsign": "DG2GG-27",
   "flight_id": "DG2GG-27_2026-07-04",
   "payload_type": "WSPR",
   "seed_time": "2026-07-27 08:58:00",
   "seed_lat": 56.29167,
   "seed_lon": 111.625,
   "seed_alt_m": 13140.0,
   "seed_age_h": 8.37,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-03 08:30:00",
    "lat": 57.91131,
    "lon": -81.22795,
    "alt_m": 13266.6
   },
   "member_spread_deg": {
    "lat": 37.94,
    "lon": 346.03
   }
  },
  {
   "callsign": "DJ2DS-34",
   "flight_id": "DJ2DS-34_2026-04-22",
   "payload_type": "WSPR",
   "seed_time": "2026-07-27 16:51:00",
   "seed_lat": 34.64583,
   "seed_lon": -80.5,
   "seed_alt_m": 13690.0,
   "seed_age_h": 0.48,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-03 16:15:00",
    "lat": 38.46892,
    "lon": -115.89709,
    "alt_m": 13893.1
   },
   "member_spread_deg": {
    "lat": 41.57,
    "lon": 248.47
   }
  },
  {
   "callsign": "DL0MMZ",
   "flight_id": "DL0MMZ_2026-07-24",
   "payload_type": "OTHER",
   "seed_time": "2026-07-25 15:59:04",
   "seed_lat": 36.60802,
   "seed_lon": 30.46457,
   "seed_alt_m": 8441.0,
   "seed_age_h": 49.35,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 4,
   "nominal_end": {
    "valid_time": "2026-08-01 15:30:00",
    "lat": 55.88695,
    "lon": 121.25343,
    "alt_m": 8498.4
   },
   "member_spread_deg": {
    "lat": 34.45,
    "lon": 45.4
   }
  },
  {
   "callsign": "DL0MZ-493",
   "flight_id": "DL0MZ-493_2026-07-25",
   "payload_type": "WSPR",
   "seed_time": "2026-07-26 16:06:01",
   "seed_lat": 49.625,
   "seed_lon": 25.08333,
   "seed_alt_m": 12400.0,
   "seed_age_h": 25.23,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 3,
   "nominal_end": {
    "valid_time": "2026-08-02 15:30:00",
    "lat": 48.74615,
    "lon": -164.87979,
    "alt_m": 12267.2
   },
   "member_spread_deg": {
    "lat": 23.7,
    "lon": 351.28
   }
  },
  {
   "callsign": "DL0MZ-493e",
   "flight_id": "DL0MZ-493e_2026-07-25",
   "payload_type": "WSPR",
   "seed_time": "2026-07-26 16:06:02",
   "seed_lat": 49.63134,
   "seed_lon": 25.11007,
   "seed_alt_m": 12400.0,
   "seed_age_h": 25.23,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 3,
   "nominal_end": {
    "valid_time": "2026-08-02 15:30:00",
    "lat": 46.35672,
    "lon": -157.63112,
    "alt_m": 12276.6
   },
   "member_spread_deg": {
    "lat": 24.34,
    "lon": 356.37
   }
  },
  {
   "callsign": "DN3LEO-13",
   "flight_id": "DN3LEO-13_2026-04-12",
   "payload_type": "WSPR",
   "seed_time": "2026-07-27 16:53:00",
   "seed_lat": 69.9375,
   "seed_lon": -43.125,
   "seed_alt_m": 12390.0,
   "seed_age_h": 0.45,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 3,
   "nominal_end": {
    "valid_time": "2026-08-03 17:00:00",
    "lat": 46.47609,
    "lon": 70.05237,
    "alt_m": 12357.4
   },
   "member_spread_deg": {
    "lat": 29.65,
    "lon": 210.9
   }
  },
  {
   "callsign": "DO3GU-40",
   "flight_id": "DO3GU-40_2026-06-19",
   "payload_type": "WSPR",
   "seed_time": "2026-07-24 12:15:47",
   "seed_lat": 71.20833,
   "seed_lon": 93.16667,
   "seed_alt_m": 15164.0,
   "seed_age_h": 77.07,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-07-31 11:45:00",
    "lat": 61.98652,
    "lon": 169.08927,
    "alt_m": 15013.8
   },
   "member_spread_deg": {
    "lat": 23.82,
    "lon": 344.21
   }
  },
  {
   "callsign": "EI6BFW-18",
   "flight_id": "EI6BFW-18_2026-07-25",
   "payload_type": "WSPR",
   "seed_time": "2026-07-27 06:03:00",
   "seed_lat": 52.6875,
   "seed_lon": 26.41667,
   "seed_alt_m": 12890.0,
   "seed_age_h": 11.28,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-03 05:30:00",
    "lat": 51.08982,
    "lon": -151.49171,
    "alt_m": 12537.3
   },
   "member_spread_deg": {
    "lat": 34.81,
    "lon": 358.87
   }
  },
  {
   "callsign": "K0PEA-28",
   "flight_id": "K0PEA-28_2026-01-07",
   "payload_type": "WSPR",
   "seed_time": "2026-07-23 12:15:25",
   "seed_lat": 49.85411,
   "seed_lon": 24.91668,
   "seed_alt_m": 13360.0,
   "seed_age_h": 101.08,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-07-30 11:45:00",
    "lat": 54.75202,
    "lon": 80.49587,
    "alt_m": 13630.7
   },
   "member_spread_deg": {
    "lat": 16.23,
    "lon": 321.16
   }
  },
  {
   "callsign": "K5NOT-11",
   "flight_id": "K5NOT-11_2026-06-20",
   "payload_type": "WSPR",
   "seed_time": "2026-07-27 16:50:37",
   "seed_lat": 35.31244,
   "seed_lon": -79.04167,
   "seed_alt_m": 13120.0,
   "seed_age_h": 0.49,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-03 16:15:00",
    "lat": 54.37555,
    "lon": 98.16908,
    "alt_m": 12716.9
   },
   "member_spread_deg": {
    "lat": 39.32,
    "lon": 239.99
   }
  },
  {
   "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": 10.9,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-03 06:00:00",
    "lat": 27.51969,
    "lon": 134.96634,
    "alt_m": 13085.1
   },
   "member_spread_deg": {
    "lat": 36.73,
    "lon": 323.77
   }
  },
  {
   "callsign": "KC3LBR-449",
   "flight_id": "KC3LBR-449_2026-07-06",
   "payload_type": "WSPR",
   "seed_time": "2026-07-27 16:57:03",
   "seed_lat": 80.45833,
   "seed_lon": 83.20833,
   "seed_alt_m": 13040.0,
   "seed_age_h": 0.38,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-03 17:00:00",
    "lat": 63.51892,
    "lon": -138.52784,
    "alt_m": 13456.0
   },
   "member_spread_deg": {
    "lat": 32.48,
    "lon": 162.57
   }
  },
  {
   "callsign": "KC3LBR-485",
   "flight_id": "KC3LBR-485_2026-03-19",
   "payload_type": "WSPR",
   "seed_time": "2026-07-27 10:54:48",
   "seed_lat": 58.91667,
   "seed_lon": -3.41667,
   "seed_alt_m": 12700.0,
   "seed_age_h": 6.42,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-03 10:30:00",
    "lat": 51.52677,
    "lon": 69.22618,
    "alt_m": 12801.9
   },
   "member_spread_deg": {
    "lat": 20.95,
    "lon": 114.67
   }
  },
  {
   "callsign": "KC5TRB-1",
   "flight_id": "KC5TRB-1_2026-06-20",
   "payload_type": "WSPR",
   "seed_time": "2026-07-27 16:55:43",
   "seed_lat": 51.20828,
   "seed_lon": -42.74997,
   "seed_alt_m": 13000.0,
   "seed_age_h": 0.41,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-03 17:00:00",
    "lat": 50.93549,
    "lon": 116.53706,
    "alt_m": 12967.0
   },
   "member_spread_deg": {
    "lat": 28.71,
    "lon": 104.66
   }
  },
  {
   "callsign": "KE8RES-8",
   "flight_id": "KE8RES-8_2026-06-20",
   "payload_type": "WSPR",
   "seed_time": "2026-07-27 16:46:00",
   "seed_lat": 61.45833,
   "seed_lon": -146.04167,
   "seed_alt_m": 12340.0,
   "seed_age_h": 0.57,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 3,
   "nominal_end": {
    "valid_time": "2026-08-03 16:15:00",
    "lat": 53.23679,
    "lon": -121.75745,
    "alt_m": 12527.2
   },
   "member_spread_deg": {
    "lat": 9.69,
    "lon": 118.47
   }
  },
  {
   "callsign": "KI1TEN-1",
   "flight_id": "KI1TEN-1_2026-07-23",
   "payload_type": "WSPR",
   "seed_time": "2026-07-27 16:55:27",
   "seed_lat": 43.83329,
   "seed_lon": -110.91663,
   "seed_alt_m": 12140.0,
   "seed_age_h": 0.41,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 3,
   "nominal_end": {
    "valid_time": "2026-08-03 17:00:00",
    "lat": 36.03242,
    "lon": -104.4677,
    "alt_m": 12201.7
   },
   "member_spread_deg": {
    "lat": 10.39,
    "lon": 33.93
   }
  },
  {
   "callsign": "KI6DS-11",
   "flight_id": "KI6DS-11_2026-02-03",
   "payload_type": "WSPR",
   "seed_time": "2026-07-27 16:55:45",
   "seed_lat": 59.12495,
   "seed_lon": -54.29165,
   "seed_alt_m": 13600.0,
   "seed_age_h": 0.41,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-03 17:00:00",
    "lat": 65.61028,
    "lon": 113.0219,
    "alt_m": 13265.4
   },
   "member_spread_deg": {
    "lat": 30.32,
    "lon": 259.58
   }
  },
  {
   "callsign": "N0MPM-31",
   "flight_id": "N0MPM-31_2026-04-16",
   "payload_type": "WSPR",
   "seed_time": "2026-07-21 23:53:19",
   "seed_lat": -24.02088,
   "seed_lon": -135.08331,
   "seed_alt_m": 14600.0,
   "seed_age_h": 137.45,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-07-28 23:30:00",
    "lat": -19.16002,
    "lon": 12.02111,
    "alt_m": 14550.6
   },
   "member_spread_deg": {
    "lat": 31.04,
    "lon": 115.63
   }
  },
  {
   "callsign": "PC4L-11",
   "flight_id": "PC4L-11_2026-07-16",
   "payload_type": "APRS",
   "seed_time": "2026-07-26 12:46:26",
   "seed_lat": 42.93908,
   "seed_lon": 39.39383,
   "seed_alt_m": 11696.0,
   "seed_age_h": 28.56,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 3,
   "nominal_end": {
    "valid_time": "2026-08-02 12:15:00",
    "lat": 44.72481,
    "lon": 126.03166,
    "alt_m": 12189.0
   },
   "member_spread_deg": {
    "lat": 27.12,
    "lon": 341.05
   }
  },
  {
   "callsign": "SP0LND-6",
   "flight_id": "SP0LND-6_2026-07-25",
   "payload_type": "APRS",
   "seed_time": "2026-07-26 13:19:17",
   "seed_lat": 44.85792,
   "seed_lon": 29.04891,
   "seed_alt_m": 13803.0,
   "seed_age_h": 28.01,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-02 12:45:00",
    "lat": 61.42021,
    "lon": 178.76646,
    "alt_m": 13702.6
   },
   "member_spread_deg": {
    "lat": 11.87,
    "lon": 355.7
   }
  },
  {
   "callsign": "SP2ROC-1",
   "flight_id": "SP2ROC-1_2026-03-14",
   "payload_type": "APRS",
   "seed_time": "2026-07-22 14:00:27",
   "seed_lat": 40.10083,
   "seed_lon": 44.614,
   "seed_alt_m": 14644.0,
   "seed_age_h": 123.33,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-07-29 13:30:00",
    "lat": 23.03001,
    "lon": 70.97765,
    "alt_m": 14876.1
   },
   "member_spread_deg": {
    "lat": 25.56,
    "lon": 43.34
   }
  },
  {
   "callsign": "SP2ROC-41",
   "flight_id": "SP2ROC-41_2026-01-25",
   "payload_type": "WSPR",
   "seed_time": "2026-07-27 16:46:00",
   "seed_lat": 50.70833,
   "seed_lon": -22.875,
   "seed_alt_m": 15740.0,
   "seed_age_h": 0.57,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 1,
   "nominal_end": {
    "valid_time": "2026-08-03 16:15:00",
    "lat": 68.498,
    "lon": 100.52311,
    "alt_m": 15521.0
   },
   "member_spread_deg": {
    "lat": 17.98,
    "lon": 149.66
   }
  },
  {
   "callsign": "SP6MPL-32",
   "flight_id": "SP6MPL-32_2026-01-23",
   "payload_type": "WSPR",
   "seed_time": "2026-07-21 03:17:00",
   "seed_lat": -22.31248,
   "seed_lon": 162.875,
   "seed_alt_m": 14160.0,
   "seed_age_h": 158.05,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 1,
   "nominal_end": {
    "valid_time": "2026-07-28 02:45:00",
    "lat": -12.58669,
    "lon": -109.39824,
    "alt_m": 14351.5
   },
   "member_spread_deg": {
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    "lon": 349.9
   }
  },
  {
   "callsign": "SP6MPL-34",
   "flight_id": "SP6MPL-34_2025-12-03",
   "payload_type": "WSPR",
   "seed_time": "2026-07-27 06:57:00",
   "seed_lat": 70.5,
   "seed_lon": 159.16667,
   "seed_alt_m": 13340.0,
   "seed_age_h": 10.38,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-03 06:30:00",
    "lat": 59.39041,
    "lon": -105.11922,
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   },
   "member_spread_deg": {
    "lat": 16.63,
    "lon": 77.44
   }
  },
  {
   "callsign": "W0DLK-1",
   "flight_id": "W0DLK-1_2026-06-20",
   "payload_type": "WSPR",
   "seed_time": "2026-07-21 06:43:47",
   "seed_lat": 46.18745,
   "seed_lon": 121.75004,
   "seed_alt_m": 12630.0,
   "seed_age_h": 154.6,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-07-28 06:15:00",
    "lat": 40.68546,
    "lon": -165.43552,
    "alt_m": 13066.3
   },
   "member_spread_deg": {
    "lat": 28.26,
    "lon": 345.01
   }
  },
  {
   "callsign": "YU9OMT-1",
   "flight_id": "YU9OMT-1_2026-05-24",
   "payload_type": "WSPR",
   "seed_time": "2026-07-26 12:50:00",
   "seed_lat": 39.60417,
   "seed_lon": 35.08336,
   "seed_alt_m": 11370.0,
   "seed_age_h": 28.5,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-02 12:15:00",
    "lat": 50.66633,
    "lon": 151.64443,
    "alt_m": 11384.1
   },
   "member_spread_deg": {
    "lat": 31.12,
    "lon": 332.53
   }
  },
  {
   "callsign": "ZS6SRC-37",
   "flight_id": "ZS6SRC-37_2026-07-15",
   "payload_type": "WSPR",
   "seed_time": "2026-07-27 14:19:00",
   "seed_lat": -23.25,
   "seed_lon": 17.04167,
   "seed_alt_m": 12190.0,
   "seed_age_h": 3.02,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 3,
   "nominal_end": {
    "valid_time": "2026-08-03 13:45:00",
    "lat": -17.78325,
    "lon": -57.09573,
    "alt_m": 12569.1
   },
   "member_spread_deg": {
    "lat": 13.84,
    "lon": 76.36
   }
  },
  {
   "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": 2.0,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-03 14:45:00",
    "lat": -14.59509,
    "lon": -151.92648,
    "alt_m": 13126.7
   },
   "member_spread_deg": {
    "lat": 20.12,
    "lon": 297.38
   }
  }
 ]
}