{
 "generated_utc": "2026-08-11T05:27:37Z",
 "gfs_cycle_utc": "2026-08-11T00:00:00Z",
 "model": {
  "source": "NCEP GFS 0.50 degree",
  "vertical_coordinate": "constant density (isopycnic)",
  "horizon_hours": 494.5,
  "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_20260811_00Z.csv.gz",
  "trajectories_geojson_gz": "PBA_forecast_20260811_00Z.geojson.gz"
 },
 "counts": {
  "flights": 28,
  "members": 9,
  "rows": 131184
 },
 "flights": [
  {
   "callsign": "AG6NS-23",
   "flight_id": "AG6NS-23_2026-02-07",
   "payload_type": "WSPR",
   "seed_time": "2026-08-11 01:23:40",
   "seed_lat": -45.1875,
   "seed_lon": -138.20832,
   "seed_alt_m": 12300.0,
   "seed_age_h": 3.94,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 3,
   "nominal_end": {
    "valid_time": "2026-08-18 01:00:00",
    "lat": -60.9112,
    "lon": 161.7035,
    "alt_m": 12562.6
   },
   "member_spread_deg": {
    "lat": 32.64,
    "lon": 348.19
   },
   "member_spread_now_deg": {
    "lat": 0.56,
    "lon": 1.38
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "BSS53",
   "flight_id": "BSS53_2026-03-09",
   "payload_type": "WSPR",
   "seed_time": "2026-08-10 20:48:19",
   "seed_lat": 48.79167,
   "seed_lon": -33.95833,
   "seed_alt_m": 12620.0,
   "seed_age_h": 8.53,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-17 23:45:00",
    "lat": 57.39218,
    "lon": 126.31951,
    "alt_m": 12665.8
   },
   "member_spread_deg": {
    "lat": 15.86,
    "lon": 56.51
   },
   "member_spread_now_deg": {
    "lat": 0.77,
    "lon": 4.2
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "BSS54",
   "flight_id": "BSS54_2026-07-09",
   "payload_type": "WSPR",
   "seed_time": "2026-08-11 02:45:18",
   "seed_lat": 46.66667,
   "seed_lon": 116.08333,
   "seed_alt_m": 14120.0,
   "seed_age_h": 2.58,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 1,
   "nominal_end": {
    "valid_time": "2026-08-18 02:15:00",
    "lat": 26.21013,
    "lon": 155.72426,
    "alt_m": 14551.1
   },
   "member_spread_deg": {
    "lat": 26.69,
    "lon": 25.28
   },
   "member_spread_now_deg": {
    "lat": 0.88,
    "lon": 1.86
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "DG2GG-23",
   "flight_id": "DG2GG-23_2026-05-23",
   "payload_type": "WSPR",
   "seed_time": "2026-08-10 18:54:00",
   "seed_lat": 41.20833,
   "seed_lon": -43.79167,
   "seed_alt_m": 12880.0,
   "seed_age_h": 10.43,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-17 23:30:00",
    "lat": 44.27125,
    "lon": 105.98268,
    "alt_m": 12648.4
   },
   "member_spread_deg": {
    "lat": 5.66,
    "lon": 52.77
   },
   "member_spread_now_deg": {
    "lat": 0.9,
    "lon": 3.46
   },
   "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": 29.03,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 1,
   "nominal_end": {
    "valid_time": "2026-08-17 23:45:00",
    "lat": 18.84432,
    "lon": -111.78826,
    "alt_m": 14083.4
   },
   "member_spread_deg": {
    "lat": 24.37,
    "lon": 40.72
   },
   "member_spread_now_deg": {
    "lat": 10.75,
    "lon": 10.8
   },
   "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": 168.38,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-17 23:30:00",
    "lat": 50.47853,
    "lon": -25.88923,
    "alt_m": 13315.6
   },
   "member_spread_deg": {
    "lat": 62.28,
    "lon": 256.29
   },
   "member_spread_now_deg": {
    "lat": 48.73,
    "lon": 277.33
   },
   "display_as": "region",
   "display_reason": "member_spread"
  },
  {
   "callsign": "DG2GG-30",
   "flight_id": "DG2GG-30_2026-08-07",
   "payload_type": "WSPR",
   "seed_time": "2026-08-11 03:26:00",
   "seed_lat": 54.16667,
   "seed_lon": 124.625,
   "seed_alt_m": 12620.0,
   "seed_age_h": 1.9,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-18 03:00:00",
    "lat": 49.04843,
    "lon": -48.12396,
    "alt_m": 12799.1
   },
   "member_spread_deg": {
    "lat": 53.98,
    "lon": 351.52
   },
   "member_spread_now_deg": {
    "lat": 0.54,
    "lon": 1.25
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "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": 326.65,
   "float_reliable": false,
   "dead_reckoned": true,
   "levels_spanned": 4,
   "nominal_end": {
    "valid_time": "2026-08-17 23:45:00",
    "lat": 40.72886,
    "lon": -177.11054,
    "alt_m": 9334.6
   },
   "member_spread_deg": {
    "lat": 39.37,
    "lon": 339.24
   },
   "member_spread_now_deg": {
    "lat": 55.49,
    "lon": 245.75
   },
   "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": 309.73,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 3,
   "nominal_end": {
    "valid_time": "2026-08-17 23:30:00",
    "lat": 68.7655,
    "lon": 89.73809,
    "alt_m": 12203.1
   },
   "member_spread_deg": {
    "lat": 37.48,
    "lon": 268.16
   },
   "member_spread_now_deg": {
    "lat": 35.79,
    "lon": 252.99
   },
   "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": 309.88,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 3,
   "nominal_end": {
    "valid_time": "2026-08-17 23:30:00",
    "lat": 41.55732,
    "lon": -13.27674,
    "alt_m": 12768.2
   },
   "member_spread_deg": {
    "lat": 42.85,
    "lon": 198.96
   },
   "member_spread_now_deg": {
    "lat": 29.53,
    "lon": 100.1
   },
   "display_as": "region",
   "display_reason": "member_spread"
  },
  {
   "callsign": "DN3LEO-13",
   "flight_id": "DN3LEO-13_2026-04-12",
   "payload_type": "WSPR",
   "seed_time": "2026-08-10 19:28:00",
   "seed_lat": 61.41667,
   "seed_lon": -27.58333,
   "seed_alt_m": 12260.0,
   "seed_age_h": 9.87,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 3,
   "nominal_end": {
    "valid_time": "2026-08-17 23:30:00",
    "lat": 82.16567,
    "lon": -137.04381,
    "alt_m": 11981.2
   },
   "member_spread_deg": {
    "lat": 26.02,
    "lon": 268.07
   },
   "member_spread_now_deg": {
    "lat": 1.57,
    "lon": 12.67
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "EI6BFW-18",
   "flight_id": "EI6BFW-18_2026-07-25",
   "payload_type": "WSPR",
   "seed_time": "2026-08-11 01:43:00",
   "seed_lat": 71.95833,
   "seed_lon": -121.25,
   "seed_alt_m": 12650.0,
   "seed_age_h": 3.62,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-18 01:15:00",
    "lat": 60.89505,
    "lon": -66.99205,
    "alt_m": 12387.3
   },
   "member_spread_deg": {
    "lat": 9.23,
    "lon": 39.53
   },
   "member_spread_now_deg": {
    "lat": 1.11,
    "lon": 3.72
   },
   "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": 25.57,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-17 23:45:00",
    "lat": 20.41477,
    "lon": -89.65003,
    "alt_m": 13499.4
   },
   "member_spread_deg": {
    "lat": 56.16,
    "lon": 283.35
   },
   "member_spread_now_deg": {
    "lat": 10.93,
    "lon": 17.04
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "KC3LBR-449",
   "flight_id": "KC3LBR-449_2026-07-06",
   "payload_type": "WSPR",
   "seed_time": "2026-08-10 21:47:18",
   "seed_lat": 48.875,
   "seed_lon": -36.33333,
   "seed_alt_m": 13470.0,
   "seed_age_h": 7.55,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-17 23:45:00",
    "lat": 57.00992,
    "lon": 108.66146,
    "alt_m": 13383.9
   },
   "member_spread_deg": {
    "lat": 21.68,
    "lon": 69.17
   },
   "member_spread_now_deg": {
    "lat": 0.61,
    "lon": 2.69
   },
   "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": 332.2,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-17 23:45:00",
    "lat": 44.8371,
    "lon": -2.42461,
    "alt_m": 13016.3
   },
   "member_spread_deg": {
    "lat": 50.91,
    "lon": 225.62
   },
   "member_spread_now_deg": {
    "lat": 45.25,
    "lon": 334.67
   },
   "display_as": "region",
   "display_reason": "member_spread"
  },
  {
   "callsign": "KC5TRB-1",
   "flight_id": "KC5TRB-1_2026-06-20",
   "payload_type": "WSPR",
   "seed_time": "2026-08-10 16:58:13",
   "seed_lat": 63.49995,
   "seed_lon": -28.5833,
   "seed_alt_m": 12660.0,
   "seed_age_h": 12.36,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-17 23:30:00",
    "lat": 54.55526,
    "lon": 58.00627,
    "alt_m": 12520.0
   },
   "member_spread_deg": {
    "lat": 13.38,
    "lon": 79.38
   },
   "member_spread_now_deg": {
    "lat": 0.94,
    "lon": 8.98
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "KD7FXO-1",
   "flight_id": "KD7FXO-1_2026-08-02",
   "payload_type": "WSPR",
   "seed_time": "2026-08-10 19:30:00",
   "seed_lat": 37.70833,
   "seed_lon": -17.875,
   "seed_alt_m": 13130.0,
   "seed_age_h": 9.83,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-17 23:30:00",
    "lat": 45.1284,
    "lon": 89.65173,
    "alt_m": 12768.7
   },
   "member_spread_deg": {
    "lat": 11.38,
    "lon": 82.2
   },
   "member_spread_now_deg": {
    "lat": 1.05,
    "lon": 1.87
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "KE8RES-8",
   "flight_id": "KE8RES-8_2026-06-20",
   "payload_type": "WSPR",
   "seed_time": "2026-08-10 22:16:00",
   "seed_lat": 54.5625,
   "seed_lon": -84.79167,
   "seed_alt_m": 12000.0,
   "seed_age_h": 7.07,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 3,
   "nominal_end": {
    "valid_time": "2026-08-17 23:45:00",
    "lat": 71.92258,
    "lon": -8.44832,
    "alt_m": 12186.3
   },
   "member_spread_deg": {
    "lat": 36.59,
    "lon": 108.57
   },
   "member_spread_now_deg": {
    "lat": 0.8,
    "lon": 1.87
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "KE9DAB-11",
   "flight_id": "KE9DAB-11_2026-07-29",
   "payload_type": "WSPR",
   "seed_time": "2026-08-11 04:06:00",
   "seed_lat": 49.3125,
   "seed_lon": 81.45833,
   "seed_alt_m": 12120.0,
   "seed_age_h": 1.23,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 3,
   "nominal_end": {
    "valid_time": "2026-08-18 03:30:00",
    "lat": 28.7681,
    "lon": -145.73488,
    "alt_m": 12498.2
   },
   "member_spread_deg": {
    "lat": 42.25,
    "lon": 66.03
   },
   "member_spread_now_deg": {
    "lat": 0.12,
    "lon": 0.71
   },
   "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": 222.41,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 3,
   "nominal_end": {
    "valid_time": "2026-08-17 23:30:00",
    "lat": 7.66504,
    "lon": -111.77348,
    "alt_m": 12350.7
   },
   "member_spread_deg": {
    "lat": 23.61,
    "lon": 109.45
   },
   "member_spread_now_deg": {
    "lat": 18.53,
    "lon": 42.92
   },
   "display_as": "region",
   "display_reason": "seed_age"
  },
  {
   "callsign": "KI6DS-11",
   "flight_id": "KI6DS-11_2026-02-03",
   "payload_type": "WSPR",
   "seed_time": "2026-08-10 17:35:45",
   "seed_lat": 55.70828,
   "seed_lon": 5.41669,
   "seed_alt_m": 13480.0,
   "seed_age_h": 11.74,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-17 23:30:00",
    "lat": 63.32948,
    "lon": 131.5541,
    "alt_m": 13121.8
   },
   "member_spread_deg": {
    "lat": 32.98,
    "lon": 310.36
   },
   "member_spread_now_deg": {
    "lat": 2.71,
    "lon": 10.21
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "SP2ROC-41",
   "flight_id": "SP2ROC-41_2026-01-25",
   "payload_type": "WSPR",
   "seed_time": "2026-08-11 04:48:30",
   "seed_lat": 37.41667,
   "seed_lon": 178.70833,
   "seed_alt_m": 16270.0,
   "seed_age_h": 0.53,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 1,
   "nominal_end": {
    "valid_time": "2026-08-18 04:15:00",
    "lat": 10.75091,
    "lon": 103.93074,
    "alt_m": 16745.9
   },
   "member_spread_deg": {
    "lat": 52.19,
    "lon": 327.49
   },
   "member_spread_now_deg": {
    "lat": 0.03,
    "lon": 0.14
   },
   "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": 250.47,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-17 23:45:00",
    "lat": 52.54937,
    "lon": -67.0577,
    "alt_m": 13012.7
   },
   "member_spread_deg": {
    "lat": 31.59,
    "lon": 291.91
   },
   "member_spread_now_deg": {
    "lat": 30.09,
    "lon": 339.23
   },
   "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": 169.24,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-17 23:30:00",
    "lat": 44.49504,
    "lon": 111.56969,
    "alt_m": 12762.2
   },
   "member_spread_deg": {
    "lat": 31.81,
    "lon": 267.27
   },
   "member_spread_now_deg": {
    "lat": 24.17,
    "lon": 328.53
   },
   "display_as": "region",
   "display_reason": "member_spread"
  },
  {
   "callsign": "VE3VRO-36",
   "flight_id": "VE3VRO-36_2026-07-30",
   "payload_type": "WSPR",
   "seed_time": "2026-08-11 00:51:00",
   "seed_lat": 49.16667,
   "seed_lon": 117.375,
   "seed_alt_m": 13220.0,
   "seed_age_h": 4.48,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-18 00:15:00",
    "lat": 26.1208,
    "lon": 165.67992,
    "alt_m": 13581.7
   },
   "member_spread_deg": {
    "lat": 27.63,
    "lon": 344.41
   },
   "member_spread_now_deg": {
    "lat": 0.49,
    "lon": 5.32
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "W0RBO-12",
   "flight_id": "W0RBO-12_2026-05-02",
   "payload_type": "WSPR",
   "seed_time": "2026-08-11 04:55:23",
   "seed_lat": 52.64578,
   "seed_lon": 82.37502,
   "seed_alt_m": 13480.0,
   "seed_age_h": 0.41,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-08-18 05:00:00",
    "lat": 56.35528,
    "lon": -143.46973,
    "alt_m": 13418.5
   },
   "member_spread_deg": {
    "lat": 35.89,
    "lon": 346.3
   },
   "member_spread_now_deg": {
    "lat": 0.02,
    "lon": 0.14
   },
   "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": 264.77,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 3,
   "nominal_end": {
    "valid_time": "2026-08-17 23:30:00",
    "lat": -7.80807,
    "lon": 41.26713,
    "alt_m": 12622.1
   },
   "member_spread_deg": {
    "lat": 33.78,
    "lon": 301.7
   },
   "member_spread_now_deg": {
    "lat": 25.59,
    "lon": 216.58
   },
   "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 06:11:00",
   "seed_lat": -23.0,
   "seed_lon": 114.875,
   "seed_alt_m": 15730.0,
   "seed_age_h": 23.15,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 1,
   "nominal_end": {
    "valid_time": "2026-08-17 23:45:00",
    "lat": -17.43732,
    "lon": -110.44454,
    "alt_m": 15717.5
   },
   "member_spread_deg": {
    "lat": 37.3,
    "lon": 310.16
   },
   "member_spread_now_deg": {
    "lat": 6.29,
    "lon": 24.76
   },
   "display_as": "track",
   "display_reason": "fresh"
  }
 ]
}