{
 "generated_utc": "2026-09-21T23:27:43Z",
 "gfs_cycle_utc": "2026-09-21T18:00:00Z",
 "model": {
  "source": "NCEP GFS 0.50 degree",
  "vertical_coordinate": "constant density (isopycnic)",
  "horizon_hours": 476.0,
  "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_20260921_18Z.csv.gz",
  "trajectories_geojson_gz": "PBA_forecast_20260921_18Z.geojson.gz"
 },
 "counts": {
  "flights": 48,
  "members": 9,
  "rows": 202104
 },
 "flights": [
  {
   "callsign": "AE4ZZ-22",
   "flight_id": "AE4ZZ-22_2026-09-19",
   "payload_type": "WSPR",
   "seed_time": "2026-09-21 18:53:45",
   "seed_lat": 38.41662,
   "seed_lon": -69.49996,
   "seed_alt_m": 13560.0,
   "seed_age_h": 4.44,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-09-28 18:30:00",
    "lat": 38.42476,
    "lon": 43.91409,
    "alt_m": 13277.6
   },
   "member_spread_deg": {
    "lat": 26.56,
    "lon": 100.15
   },
   "member_spread_now_deg": {
    "lat": 0.26,
    "lon": 1.88
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "AG6NS-23",
   "flight_id": "AG6NS-23_2026-02-07",
   "payload_type": "WSPR",
   "seed_time": "2026-09-21 16:53:40",
   "seed_lat": -67.52083,
   "seed_lon": -38.83332,
   "seed_alt_m": 12270.0,
   "seed_age_h": 6.44,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 3,
   "nominal_end": {
    "valid_time": "2026-09-28 17:30:00",
    "lat": -58.78131,
    "lon": -11.80304,
    "alt_m": 12404.5
   },
   "member_spread_deg": {
    "lat": 8.01,
    "lon": 109.03
   },
   "member_spread_now_deg": {
    "lat": 2.28,
    "lon": 2.62
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "BSS52",
   "flight_id": "BSS52_2025-12-25",
   "payload_type": "WSPR",
   "seed_time": "2026-09-21 22:49:18",
   "seed_lat": 43.45833,
   "seed_lon": 174.0,
   "seed_alt_m": 13580.0,
   "seed_age_h": 0.51,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-09-28 22:15:00",
    "lat": 25.46327,
    "lon": -149.72814,
    "alt_m": 13711.4
   },
   "member_spread_deg": {
    "lat": 21.81,
    "lon": 349.4
   },
   "member_spread_now_deg": {
    "lat": 0.34,
    "lon": 0.07
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "BSS53",
   "flight_id": "BSS53_2026-03-09",
   "payload_type": "WSPR",
   "seed_time": "2026-09-21 22:46:48",
   "seed_lat": 51.25,
   "seed_lon": 146.33333,
   "seed_alt_m": 12450.0,
   "seed_age_h": 0.55,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-09-28 22:15:00",
    "lat": 27.5522,
    "lon": -2.53673,
    "alt_m": 13277.0
   },
   "member_spread_deg": {
    "lat": 40.76,
    "lon": 185.41
   },
   "member_spread_now_deg": {
    "lat": 0.09,
    "lon": 0.14
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "BSS54",
   "flight_id": "BSS54_2026-07-09",
   "payload_type": "WSPR",
   "seed_time": "2026-09-18 15:23:18",
   "seed_lat": 40.79167,
   "seed_lon": 19.75,
   "seed_alt_m": 14090.0,
   "seed_age_h": 79.95,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-09-28 17:30:00",
    "lat": 45.06943,
    "lon": -104.86042,
    "alt_m": 13734.8
   },
   "member_spread_deg": {
    "lat": 23.38,
    "lon": 334.51
   },
   "member_spread_now_deg": {
    "lat": 12.04,
    "lon": 40.42
   },
   "display_as": "region",
   "display_reason": "seed_age"
  },
  {
   "callsign": "BZ-7",
   "flight_id": "BZ-7_2026-08-06",
   "payload_type": "WSPR",
   "seed_time": "2026-09-20 07:29:00",
   "seed_lat": 31.91667,
   "seed_lon": 0.95833,
   "seed_alt_m": 11580.0,
   "seed_age_h": 39.85,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-09-28 17:30:00",
    "lat": 40.22553,
    "lon": 111.56426,
    "alt_m": 11227.8
   },
   "member_spread_deg": {
    "lat": 31.44,
    "lon": 307.13
   },
   "member_spread_now_deg": {
    "lat": 2.64,
    "lon": 20.86
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "DF7PN-427",
   "flight_id": "DF7PN-427_2026-08-03",
   "payload_type": "WSPR",
   "seed_time": "2026-09-21 06:04:31",
   "seed_lat": 45.25,
   "seed_lon": 106.33333,
   "seed_alt_m": 12200.0,
   "seed_age_h": 17.26,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 3,
   "nominal_end": {
    "valid_time": "2026-09-28 17:30:00",
    "lat": 37.46763,
    "lon": -69.40954,
    "alt_m": 12140.2
   },
   "member_spread_deg": {
    "lat": 32.6,
    "lon": 177.92
   },
   "member_spread_now_deg": {
    "lat": 3.37,
    "lon": 3.52
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "DF7PN-427e",
   "flight_id": "DF7PN-427e_2026-08-03",
   "payload_type": "WSPR",
   "seed_time": "2026-09-20 04:45:02",
   "seed_lat": 44.90608,
   "seed_lon": 79.22761,
   "seed_alt_m": 12240.0,
   "seed_age_h": 42.58,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 3,
   "nominal_end": {
    "valid_time": "2026-09-28 17:45:00",
    "lat": 49.81121,
    "lon": -39.16503,
    "alt_m": 12212.9
   },
   "member_spread_deg": {
    "lat": 36.57,
    "lon": 181.81
   },
   "member_spread_now_deg": {
    "lat": 1.33,
    "lon": 4.47
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "DG2GG-30",
   "flight_id": "DG2GG-30_2026-08-07",
   "payload_type": "WSPR",
   "seed_time": "2026-09-21 07:06:00",
   "seed_lat": 62.91667,
   "seed_lon": 23.0,
   "seed_alt_m": 11970.0,
   "seed_age_h": 16.23,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 3,
   "nominal_end": {
    "valid_time": "2026-09-28 17:30:00",
    "lat": 51.95902,
    "lon": 69.59704,
    "alt_m": 12806.8
   },
   "member_spread_deg": {
    "lat": 25.27,
    "lon": 90.23
   },
   "member_spread_now_deg": {
    "lat": 1.18,
    "lon": 2.25
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "DG2GG-31",
   "flight_id": "DG2GG-31_2026-08-13",
   "payload_type": "WSPR",
   "seed_time": "2026-09-21 10:17:00",
   "seed_lat": 39.79167,
   "seed_lon": 73.16667,
   "seed_alt_m": 13180.0,
   "seed_age_h": 13.05,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-09-28 17:45:00",
    "lat": 52.92173,
    "lon": -38.04691,
    "alt_m": 12664.3
   },
   "member_spread_deg": {
    "lat": 22.22,
    "lon": 90.79
   },
   "member_spread_now_deg": {
    "lat": 0.89,
    "lon": 2.69
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "DG2GG-32",
   "flight_id": "DG2GG-32_2026-09-03",
   "payload_type": "WSPR",
   "seed_time": "2026-09-21 07:46:00",
   "seed_lat": 43.47917,
   "seed_lon": 76.75,
   "seed_alt_m": 13400.0,
   "seed_age_h": 15.57,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-09-28 17:45:00",
    "lat": 67.70755,
    "lon": -91.77477,
    "alt_m": 12950.8
   },
   "member_spread_deg": {
    "lat": 13.88,
    "lon": 61.15
   },
   "member_spread_now_deg": {
    "lat": 0.96,
    "lon": 2.39
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "DG2GG-34",
   "flight_id": "DG2GG-34_2026-09-15",
   "payload_type": "WSPR",
   "seed_time": "2026-09-21 06:15:00",
   "seed_lat": 43.35417,
   "seed_lon": 129.79167,
   "seed_alt_m": 13080.0,
   "seed_age_h": 17.08,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-09-28 17:45:00",
    "lat": 36.87045,
    "lon": -111.69169,
    "alt_m": 13281.2
   },
   "member_spread_deg": {
    "lat": 40.22,
    "lon": 352.63
   },
   "member_spread_now_deg": {
    "lat": 5.84,
    "lon": 10.32
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "DO3GU-44",
   "flight_id": "DO3GU-44_2026-07-29",
   "payload_type": "WSPR",
   "seed_time": "2026-09-18 13:18:43",
   "seed_lat": 35.89583,
   "seed_lon": -76.25,
   "seed_alt_m": 15219.0,
   "seed_age_h": 82.02,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-09-28 17:45:00",
    "lat": 17.16308,
    "lon": -37.96613,
    "alt_m": 15229.1
   },
   "member_spread_deg": {
    "lat": 49.11,
    "lon": 116.06
   },
   "member_spread_now_deg": {
    "lat": 11.67,
    "lon": 18.95
   },
   "display_as": "region",
   "display_reason": "seed_age"
  },
  {
   "callsign": "DO3GU-48",
   "flight_id": "DO3GU-48_2026-09-08",
   "payload_type": "WSPR",
   "seed_time": "2026-09-18 07:36:22",
   "seed_lat": 68.0,
   "seed_lon": 83.29167,
   "seed_alt_m": 14417.0,
   "seed_age_h": 87.73,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-09-28 17:30:00",
    "lat": 69.31917,
    "lon": -72.53597,
    "alt_m": 14215.9
   },
   "member_spread_deg": {
    "lat": 8.85,
    "lon": 79.45
   },
   "member_spread_now_deg": {
    "lat": 6.25,
    "lon": 21.08
   },
   "display_as": "region",
   "display_reason": "seed_age"
  },
  {
   "callsign": "DO3GU-49",
   "flight_id": "DO3GU-49_2026-09-15",
   "payload_type": "WSPR",
   "seed_time": "2026-09-19 12:40:28",
   "seed_lat": 39.83333,
   "seed_lon": 60.66667,
   "seed_alt_m": 13990.0,
   "seed_age_h": 58.66,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 1,
   "nominal_end": {
    "valid_time": "2026-09-28 17:45:00",
    "lat": 34.13732,
    "lon": -115.05186,
    "alt_m": 14101.2
   },
   "member_spread_deg": {
    "lat": 45.08,
    "lon": 107.6
   },
   "member_spread_now_deg": {
    "lat": 5.64,
    "lon": 40.56
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "DO3GU-8",
   "flight_id": "DO3GU-8_2026-08-12",
   "payload_type": "APRS",
   "seed_time": "2026-09-18 08:14:06",
   "seed_lat": 42.27058,
   "seed_lon": 26.24284,
   "seed_alt_m": 14576.0,
   "seed_age_h": 87.1,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-09-28 17:45:00",
    "lat": 61.17325,
    "lon": -75.19332,
    "alt_m": 13977.2
   },
   "member_spread_deg": {
    "lat": 28.33,
    "lon": 94.69
   },
   "member_spread_now_deg": {
    "lat": 5.72,
    "lon": 20.71
   },
   "display_as": "region",
   "display_reason": "seed_age"
  },
  {
   "callsign": "EI6BFW-18",
   "flight_id": "EI6BFW-18_2026-07-25",
   "payload_type": "WSPR",
   "seed_time": "2026-09-21 22:28:00",
   "seed_lat": 34.45833,
   "seed_lon": -94.08333,
   "seed_alt_m": 13530.0,
   "seed_age_h": 0.87,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-09-28 22:00:00",
    "lat": 46.02431,
    "lon": 127.20991,
    "alt_m": 12890.5
   },
   "member_spread_deg": {
    "lat": 30.89,
    "lon": 168.74
   },
   "member_spread_now_deg": {
    "lat": 0.1,
    "lon": 0.16
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "I1RFQ",
   "flight_id": "I1RFQ_2026-09-06",
   "payload_type": "WSPR",
   "seed_time": "2026-09-10 05:25:00",
   "seed_lat": 48.52083,
   "seed_lon": 159.54167,
   "seed_alt_m": 12130.0,
   "seed_age_h": 281.92,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 3,
   "nominal_end": {
    "valid_time": "2026-09-28 17:30:00",
    "lat": 25.09907,
    "lon": -50.24534,
    "alt_m": 12794.0
   },
   "member_spread_deg": {
    "lat": 63.02,
    "lon": 187.45
   },
   "member_spread_now_deg": {
    "lat": 32.45,
    "lon": 234.62
   },
   "display_as": "region",
   "display_reason": "member_spread"
  },
  {
   "callsign": "KC3LBR-485",
   "flight_id": "KC3LBR-485_2026-03-19",
   "payload_type": "WSPR",
   "seed_time": "2026-09-15 23:15:47",
   "seed_lat": 26.64583,
   "seed_lon": -149.20833,
   "seed_alt_m": 13760.0,
   "seed_age_h": 144.07,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-09-28 17:45:00",
    "lat": 25.91558,
    "lon": -21.07231,
    "alt_m": 13903.6
   },
   "member_spread_deg": {
    "lat": 29.29,
    "lon": 219.82
   },
   "member_spread_now_deg": {
    "lat": 42.22,
    "lon": 96.17
   },
   "display_as": "region",
   "display_reason": "member_spread"
  },
  {
   "callsign": "KC5TRB-1",
   "flight_id": "KC5TRB-1_2026-06-20",
   "payload_type": "WSPR",
   "seed_time": "2026-09-20 04:55:43",
   "seed_lat": 47.10411,
   "seed_lon": 148.79169,
   "seed_alt_m": 13000.0,
   "seed_age_h": 42.41,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-09-28 17:30:00",
    "lat": 43.68999,
    "lon": -60.10211,
    "alt_m": 12994.7
   },
   "member_spread_deg": {
    "lat": 18.3,
    "lon": 74.75
   },
   "member_spread_now_deg": {
    "lat": 7.37,
    "lon": 355.35
   },
   "display_as": "region",
   "display_reason": "member_spread"
  },
  {
   "callsign": "KD7FXO-1",
   "flight_id": "KD7FXO-1_2026-08-02",
   "payload_type": "WSPR",
   "seed_time": "2026-09-12 06:05:00",
   "seed_lat": 45.47917,
   "seed_lon": 159.375,
   "seed_alt_m": 12660.0,
   "seed_age_h": 233.25,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-09-28 17:30:00",
    "lat": 45.60759,
    "lon": -158.54068,
    "alt_m": 12381.7
   },
   "member_spread_deg": {
    "lat": 28.14,
    "lon": 304.67
   },
   "member_spread_now_deg": {
    "lat": 27.68,
    "lon": 190.47
   },
   "display_as": "region",
   "display_reason": "member_spread"
  },
  {
   "callsign": "KE8RES-8",
   "flight_id": "KE8RES-8_2026-06-20",
   "payload_type": "WSPR",
   "seed_time": "2026-09-13 13:01:00",
   "seed_lat": 42.0625,
   "seed_lon": 28.04167,
   "seed_alt_m": 12700.0,
   "seed_age_h": 202.32,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-09-28 17:30:00",
    "lat": 59.71632,
    "lon": 58.2259,
    "alt_m": 12763.4
   },
   "member_spread_deg": {
    "lat": 43.57,
    "lon": 197.04
   },
   "member_spread_now_deg": {
    "lat": 12.71,
    "lon": 83.66
   },
   "display_as": "region",
   "display_reason": "member_spread"
  },
  {
   "callsign": "KI6DS-11",
   "flight_id": "KI6DS-11_2026-02-03",
   "payload_type": "WSPR",
   "seed_time": "2026-09-21 22:55:45",
   "seed_lat": 55.16661,
   "seed_lon": -162.58331,
   "seed_alt_m": 12840.0,
   "seed_age_h": 0.41,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-09-28 23:00:00",
    "lat": 62.96495,
    "lon": -25.82168,
    "alt_m": 12617.5
   },
   "member_spread_deg": {
    "lat": 5.83,
    "lon": 7.8
   },
   "member_spread_now_deg": {
    "lat": 0.06,
    "lon": 0.1
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "KJ4AWK-1",
   "flight_id": "KJ4AWK-1_2026-08-22",
   "payload_type": "APRS",
   "seed_time": "2026-09-13 11:22:57",
   "seed_lat": 73.68216,
   "seed_lon": 37.14858,
   "seed_alt_m": 12487.0,
   "seed_age_h": 203.95,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-09-28 17:30:00",
    "lat": 76.77088,
    "lon": 11.49824,
    "alt_m": 12047.4
   },
   "member_spread_deg": {
    "lat": 34.34,
    "lon": 345.9
   },
   "member_spread_now_deg": {
    "lat": 17.39,
    "lon": 315.4
   },
   "display_as": "region",
   "display_reason": "member_spread"
  },
  {
   "callsign": "KO4VAQ-1",
   "flight_id": "KO4VAQ-1_2026-09-07",
   "payload_type": "WSPR",
   "seed_time": "2026-09-21 18:23:25",
   "seed_lat": 33.35411,
   "seed_lon": -147.87499,
   "seed_alt_m": 13240.0,
   "seed_age_h": 4.94,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-09-28 18:00:00",
    "lat": 28.87653,
    "lon": 0.70296,
    "alt_m": 13222.2
   },
   "member_spread_deg": {
    "lat": 24.85,
    "lon": 42.83
   },
   "member_spread_now_deg": {
    "lat": 0.56,
    "lon": 4.01
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "KS4VA-27",
   "flight_id": "KS4VA-27_2026-08-29",
   "payload_type": "WSPR",
   "seed_time": "2026-09-20 17:01:27",
   "seed_lat": 22.39578,
   "seed_lon": 15.66669,
   "seed_alt_m": 15250.0,
   "seed_age_h": 30.31,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-09-28 17:30:00",
    "lat": 28.37034,
    "lon": 147.62813,
    "alt_m": 15307.8
   },
   "member_spread_deg": {
    "lat": 10.97,
    "lon": 319.24
   },
   "member_spread_now_deg": {
    "lat": 4.63,
    "lon": 7.66
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "N0MPM-31",
   "flight_id": "N0MPM-31_2026-04-16",
   "payload_type": "WSPR",
   "seed_time": "2026-09-21 06:33:19",
   "seed_lat": 47.37495,
   "seed_lon": 103.37502,
   "seed_alt_m": 13900.0,
   "seed_age_h": 16.78,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 1,
   "nominal_end": {
    "valid_time": "2026-09-28 17:30:00",
    "lat": 42.31442,
    "lon": -71.6679,
    "alt_m": 14121.9
   },
   "member_spread_deg": {
    "lat": 49.6,
    "lon": 236.52
   },
   "member_spread_now_deg": {
    "lat": 0.76,
    "lon": 8.67
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "N4TVV-4",
   "flight_id": "N4TVV-4_2026-09-05",
   "payload_type": "APRS",
   "seed_time": "2026-09-21 23:04:25",
   "seed_lat": 46.07866,
   "seed_lon": 146.924,
   "seed_alt_m": 12696.0,
   "seed_age_h": 0.26,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-09-28 23:00:00",
    "lat": 3.62437,
    "lon": 101.91412,
    "alt_m": 13227.8
   },
   "member_spread_deg": {
    "lat": 45.7,
    "lon": 356.73
   },
   "member_spread_now_deg": {
    "lat": 0.23,
    "lon": 0.29
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "NE9JJ-11",
   "flight_id": "NE9JJ-11_2026-09-11",
   "payload_type": "WSPR",
   "seed_time": "2026-09-21 22:23:00",
   "seed_lat": 29.54167,
   "seed_lon": 179.83333,
   "seed_alt_m": 13140.0,
   "seed_age_h": 0.95,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-09-28 22:00:00",
    "lat": 42.51248,
    "lon": -11.35532,
    "alt_m": 12814.4
   },
   "member_spread_deg": {
    "lat": 23.12,
    "lon": 84.35
   },
   "member_spread_now_deg": {
    "lat": 0.54,
    "lon": 0.38
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "NQ1W-6",
   "flight_id": "NQ1W-6_2026-09-11",
   "payload_type": "WSPR",
   "seed_time": "2026-09-21 05:41:00",
   "seed_lat": 39.77083,
   "seed_lon": 105.16667,
   "seed_alt_m": 13060.0,
   "seed_age_h": 17.65,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-09-28 17:45:00",
    "lat": 38.51803,
    "lon": -155.84102,
    "alt_m": 13219.9
   },
   "member_spread_deg": {
    "lat": 31.35,
    "lon": 337.85
   },
   "member_spread_now_deg": {
    "lat": 2.89,
    "lon": 7.47
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "PE2BZ-11",
   "flight_id": "PE2BZ-11_2026-09-16",
   "payload_type": "APRS",
   "seed_time": "2026-09-21 15:59:27",
   "seed_lat": 42.46633,
   "seed_lon": -3.77642,
   "seed_alt_m": 12840.0,
   "seed_age_h": 7.34,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-09-28 17:30:00",
    "lat": 37.87291,
    "lon": 74.12947,
    "alt_m": 12398.1
   },
   "member_spread_deg": {
    "lat": 18.89,
    "lon": 71.58
   },
   "member_spread_now_deg": {
    "lat": 2.27,
    "lon": 0.99
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "SP0LND-12",
   "flight_id": "SP0LND-12_2026-09-19",
   "payload_type": "APRS",
   "seed_time": "2026-09-21 14:14:07",
   "seed_lat": 64.99734,
   "seed_lon": 26.84733,
   "seed_alt_m": 13239.0,
   "seed_age_h": 9.1,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-09-28 17:45:00",
    "lat": 48.83867,
    "lon": 23.37563,
    "alt_m": 13731.2
   },
   "member_spread_deg": {
    "lat": 18.1,
    "lon": 94.79
   },
   "member_spread_now_deg": {
    "lat": 0.4,
    "lon": 0.4
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "SP0LND-13",
   "flight_id": "SP0LND-13_2026-08-13",
   "payload_type": "APRS",
   "seed_time": "2026-09-15 14:54:25",
   "seed_lat": 53.91942,
   "seed_lon": -95.70808,
   "seed_alt_m": 13217.0,
   "seed_age_h": 152.43,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-09-28 17:30:00",
    "lat": 41.60619,
    "lon": 35.42795,
    "alt_m": 13563.6
   },
   "member_spread_deg": {
    "lat": 37.24,
    "lon": 294.8
   },
   "member_spread_now_deg": {
    "lat": 41.27,
    "lon": 330.34
   },
   "display_as": "region",
   "display_reason": "member_spread"
  },
  {
   "callsign": "SP0LND-14",
   "flight_id": "SP0LND-14_2026-09-09",
   "payload_type": "APRS",
   "seed_time": "2026-09-13 10:47:50",
   "seed_lat": 71.62158,
   "seed_lon": 24.96141,
   "seed_alt_m": 13354.0,
   "seed_age_h": 204.54,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-09-28 17:45:00",
    "lat": 65.83202,
    "lon": -46.15238,
    "alt_m": 12927.5
   },
   "member_spread_deg": {
    "lat": 25.56,
    "lon": 259.23
   },
   "member_spread_now_deg": {
    "lat": 38.85,
    "lon": 266.47
   },
   "display_as": "region",
   "display_reason": "member_spread"
  },
  {
   "callsign": "SP0LND-15",
   "flight_id": "SP0LND-15_2026-09-16",
   "payload_type": "APRS",
   "seed_time": "2026-09-17 07:31:21",
   "seed_lat": 46.4615,
   "seed_lon": 27.87242,
   "seed_alt_m": 14195.0,
   "seed_age_h": 111.81,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-09-28 17:30:00",
    "lat": 23.40203,
    "lon": -89.35666,
    "alt_m": 14645.6
   },
   "member_spread_deg": {
    "lat": 46.76,
    "lon": 99.74
   },
   "member_spread_now_deg": {
    "lat": 7.28,
    "lon": 50.09
   },
   "display_as": "region",
   "display_reason": "seed_age"
  },
  {
   "callsign": "SP0LND-39",
   "flight_id": "SP0LND-39_2026-08-27",
   "payload_type": "WSPR",
   "seed_time": "2026-09-21 17:55:00",
   "seed_lat": 61.45833,
   "seed_lon": -111.41667,
   "seed_alt_m": 13550.0,
   "seed_age_h": 5.42,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-09-28 17:30:00",
    "lat": 47.58365,
    "lon": 129.76037,
    "alt_m": 13534.1
   },
   "member_spread_deg": {
    "lat": 34.42,
    "lon": 127.65
   },
   "member_spread_now_deg": {
    "lat": 0.7,
    "lon": 7.36
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "SP0LND-6",
   "flight_id": "SP0LND-6_2026-09-06",
   "payload_type": "APRS",
   "seed_time": "2026-09-21 01:02:23",
   "seed_lat": 44.55234,
   "seed_lon": -123.39266,
   "seed_alt_m": 14174.0,
   "seed_age_h": 22.29,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-09-28 17:30:00",
    "lat": 35.07365,
    "lon": 1.07508,
    "alt_m": 14216.5
   },
   "member_spread_deg": {
    "lat": 22.98,
    "lon": 70.54
   },
   "member_spread_now_deg": {
    "lat": 6.45,
    "lon": 7.39
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "SP0LND-9",
   "flight_id": "SP0LND-9_2026-08-27",
   "payload_type": "APRS",
   "seed_time": "2026-09-13 15:15:20",
   "seed_lat": 42.07925,
   "seed_lon": 23.58366,
   "seed_alt_m": 13938.0,
   "seed_age_h": 200.08,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 1,
   "nominal_end": {
    "valid_time": "2026-09-28 17:45:00",
    "lat": 14.06851,
    "lon": 16.60724,
    "alt_m": 14665.3
   },
   "member_spread_deg": {
    "lat": 61.33,
    "lon": 85.37
   },
   "member_spread_now_deg": {
    "lat": 14.07,
    "lon": 93.49
   },
   "display_as": "region",
   "display_reason": "member_spread"
  },
  {
   "callsign": "SP2ROC-41",
   "flight_id": "SP2ROC-41_2026-01-25",
   "payload_type": "WSPR",
   "seed_time": "2026-09-21 10:21:00",
   "seed_lat": 63.02083,
   "seed_lon": 64.125,
   "seed_alt_m": 15400.0,
   "seed_age_h": 12.98,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-09-28 17:45:00",
    "lat": 47.51382,
    "lon": -155.63275,
    "alt_m": 15195.1
   },
   "member_spread_deg": {
    "lat": 10.19,
    "lon": 347.08
   },
   "member_spread_now_deg": {
    "lat": 1.65,
    "lon": 2.42
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "SP6MPL-32",
   "flight_id": "SP6MPL-32_2026-01-23",
   "payload_type": "WSPR",
   "seed_time": "2026-09-21 12:32:00",
   "seed_lat": 33.70835,
   "seed_lon": 31.70833,
   "seed_alt_m": 14040.0,
   "seed_age_h": 10.8,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 1,
   "nominal_end": {
    "valid_time": "2026-09-28 17:30:00",
    "lat": 53.18891,
    "lon": -77.50395,
    "alt_m": 13472.4
   },
   "member_spread_deg": {
    "lat": 28.16,
    "lon": 282.73
   },
   "member_spread_now_deg": {
    "lat": 0.8,
    "lon": 3.65
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "SP6MPL-34",
   "flight_id": "SP6MPL-34_2025-12-03",
   "payload_type": "WSPR",
   "seed_time": "2026-09-21 21:57:00",
   "seed_lat": 46.1875,
   "seed_lon": -114.75,
   "seed_alt_m": 13730.0,
   "seed_age_h": 1.38,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-09-28 21:30:00",
    "lat": 29.0943,
    "lon": 8.98852,
    "alt_m": 14055.0
   },
   "member_spread_deg": {
    "lat": 15.92,
    "lon": 49.32
   },
   "member_spread_now_deg": {
    "lat": 0.2,
    "lon": 0.46
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "VE3VRO-34",
   "flight_id": "VE3VRO-34_2026-07-30",
   "payload_type": "WSPR",
   "seed_time": "2026-09-15 04:40:00",
   "seed_lat": 72.0,
   "seed_lon": 103.25,
   "seed_alt_m": 12430.0,
   "seed_age_h": 162.67,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-09-28 17:45:00",
    "lat": 72.14838,
    "lon": 96.53634,
    "alt_m": 12016.8
   },
   "member_spread_deg": {
    "lat": 23.16,
    "lon": 232.49
   },
   "member_spread_now_deg": {
    "lat": 16.68,
    "lon": 281.46
   },
   "display_as": "region",
   "display_reason": "member_spread"
  },
  {
   "callsign": "VE3VRO-36",
   "flight_id": "VE3VRO-36_2026-07-30",
   "payload_type": "WSPR",
   "seed_time": "2026-09-21 19:51:00",
   "seed_lat": 46.625,
   "seed_lon": -64.0,
   "seed_alt_m": 12910.0,
   "seed_age_h": 3.48,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-09-28 19:15:00",
    "lat": 43.51123,
    "lon": 56.94792,
    "alt_m": 12833.6
   },
   "member_spread_deg": {
    "lat": 11.11,
    "lon": 117.31
   },
   "member_spread_now_deg": {
    "lat": 0.53,
    "lon": 3.26
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "W0RBO-12",
   "flight_id": "W0RBO-12_2026-05-02",
   "payload_type": "WSPR",
   "seed_time": "2026-09-08 21:35:23",
   "seed_lat": 52.33328,
   "seed_lon": -95.95831,
   "seed_alt_m": 12860.0,
   "seed_age_h": 313.74,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-09-28 17:30:00",
    "lat": 59.38517,
    "lon": 79.22235,
    "alt_m": 13042.1
   },
   "member_spread_deg": {
    "lat": 38.17,
    "lon": 191.92
   },
   "member_spread_now_deg": {
    "lat": 43.98,
    "lon": 334.29
   },
   "display_as": "region",
   "display_reason": "member_spread"
  },
  {
   "callsign": "W5AJ-1",
   "flight_id": "W5AJ-1_2026-08-02",
   "payload_type": "WSPR",
   "seed_time": "2026-09-14 19:55:29",
   "seed_lat": 59.41661,
   "seed_lon": -58.74997,
   "seed_alt_m": 11480.0,
   "seed_age_h": 171.41,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-09-28 17:30:00",
    "lat": 64.6639,
    "lon": 25.64704,
    "alt_m": 12121.7
   },
   "member_spread_deg": {
    "lat": 44.39,
    "lon": 306.03
   },
   "member_spread_now_deg": {
    "lat": 7.35,
    "lon": 88.29
   },
   "display_as": "region",
   "display_reason": "member_spread"
  },
  {
   "callsign": "W7EEU-11",
   "flight_id": "W7EEU-11_2026-08-23",
   "payload_type": "APRS",
   "seed_time": "2026-09-19 14:28:59",
   "seed_lat": 63.95584,
   "seed_lon": 16.81967,
   "seed_alt_m": 11926.0,
   "seed_age_h": 56.85,
   "float_reliable": true,
   "dead_reckoned": true,
   "levels_spanned": 3,
   "nominal_end": {
    "valid_time": "2026-09-28 17:30:00",
    "lat": 56.35314,
    "lon": -36.34829,
    "alt_m": 11729.6
   },
   "member_spread_deg": {
    "lat": 22.72,
    "lon": 349.41
   },
   "member_spread_now_deg": {
    "lat": 8.24,
    "lon": 52.88
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "WD4CFN-21",
   "flight_id": "WD4CFN-21_2026-09-13",
   "payload_type": "WSPR",
   "seed_time": "2026-09-21 15:50:33",
   "seed_lat": 22.52075,
   "seed_lon": -20.99989,
   "seed_alt_m": 13260.0,
   "seed_age_h": 7.49,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 2,
   "nominal_end": {
    "valid_time": "2026-09-28 17:45:00",
    "lat": 45.395,
    "lon": 172.0623,
    "alt_m": 13088.6
   },
   "member_spread_deg": {
    "lat": 28.26,
    "lon": 146.06
   },
   "member_spread_now_deg": {
    "lat": 1.52,
    "lon": 2.14
   },
   "display_as": "track",
   "display_reason": "fresh"
  },
  {
   "callsign": "ZS6WBT-1",
   "flight_id": "ZS6WBT-1_2026-08-19",
   "payload_type": "WSPR",
   "seed_time": "2026-09-21 22:18:30",
   "seed_lat": -13.35417,
   "seed_lon": 157.5,
   "seed_alt_m": 15973.0,
   "seed_age_h": 1.03,
   "float_reliable": true,
   "dead_reckoned": false,
   "levels_spanned": 1,
   "nominal_end": {
    "valid_time": "2026-09-28 21:45:00",
    "lat": -20.8835,
    "lon": -154.96504,
    "alt_m": 15836.0
   },
   "member_spread_deg": {
    "lat": 26.65,
    "lon": 355.3
   },
   "member_spread_now_deg": {
    "lat": 0.15,
    "lon": 0.39
   },
   "display_as": "track",
   "display_reason": "fresh"
  }
 ]
}