Scenario 9 - Morning Constellation
Shift Turnover Notes
Section titled “Shift Turnover Notes”Date: Wednesday 17 March, 0600 Local (Galway runs UTC in March) Station: GW-01 Galway, Ireland - NATS Europe (planning authority for the network) Operator on Duty: You, qualified, solo Site Lead: Not on shift. The qualified operator holds the console. SH-02 Shetland: Fiona MacLeod, on console for the 06:19 pass, then outside on the feed heater until 07:00 Customer: Erik Halvorsen, Nordic Maritime Watch (standing collect on the 06:18 SAR-1 window)
Evening shift’s last contact was the 22:41 SAR-2 pass; modem 1 is still on 1,370 and the analyzer is at its default. Overnight quiet, no contacts worked. GW-01 reference locked all night, no holdover, amplifier idle. Six contacts on the board for the day, none allocated. The Nordic Maritime Watch standing collect is on the board as priority 1 at 06:18.
Both sites want a full sweep before anything is committed: board, reference, receive chain, transmit chain. Plan is unbuilt. First window is in eighteen minutes.
- Night shift (turnover log, 0554)
Fiona (text, 0607):
“On console since half five and I’ve not touched the equipment, so what your console shows for my site is what I’ve got. I’ll take the seventy-three at 06:19 myself - I want eyes on the pedestal through the top - and then I’m outside on the heater cable till seven. The half-past SAR-2 is yours from there. Modem’s on 1414 for mine; don’t move it till I’m off.”
Standing Tasking NMW-STD-2027-03
Section titled “Standing Tasking NMW-STD-2027-03”| Item | Value |
|---|---|
| Customer | Erik Halvorsen, Nordic Maritime Watch |
| Requirement | MERIDIAN-SAR-1 imagery from the 06:18 Galway window, every day this week |
| Priority | 1 |
| Delivery | Decoded frames on the pass; customer status at the end of the morning windows |
| Customer preference | Coverage and commitment. He does not read C/N figures. |
Today’s Contacts (epoch 06:00:00 UTC, 0° horizon)
Section titled “Today’s Contacts (epoch 06:00:00 UTC, 0° horizon)”| Contact ID | Satellite | Horizon | Opens | Closes | Priority |
|---|---|---|---|---|---|
| M-SAR1-GW | MERIDIAN-SAR-1 | Galway, 30° pass | 06:18:00 | 06:27:30 | 1 |
| M-SAR1-SH | MERIDIAN-SAR-1 | Shetland, 73° pass | 06:19:10 | 06:29:10 | 2 |
| M-SAR2-SH | MERIDIAN-SAR-2 | Shetland, 23° pass | 06:30:00 | 06:39:20 | 1 |
| M-SAR2-GW | MERIDIAN-SAR-2 | Galway, 25° pass | 06:32:00 | 06:41:20 | 1 |
| M-SAR1-GW-2 | MERIDIAN-SAR-1 | Galway, second orbit, 18° | 07:49:50 | 07:59:00 | 3 |
| M-SAR2-SH-2 | MERIDIAN-SAR-2 | Shetland, second orbit, 5° graze | 08:02:00 | 08:08:10 | 3 |
Priority 1 and 2 contacts must be assigned for the plan to read DECONFLICTED. The two priority 3 second-orbit contacts may be assigned or left unassigned; that is a planning decision, and the customer will be told which way it went.
Overlaps
Section titled “Overlaps”| Pair | Overlap | Constraint |
|---|---|---|
| M-SAR1-GW and M-SAR1-SH | 06:19:10 to 06:27:30 | Cannot both sit on one site |
| M-SAR2-SH and M-SAR2-GW | 06:32:00 to 06:39:20 | Cannot both sit on one site |
Who flies what
Section titled “Who flies what”| Contact | Site | Operator |
|---|---|---|
| M-SAR1-GW 06:18 | GW-01 | You. Erik’s collect. |
| M-SAR1-SH 06:19 | SH-02 | Fiona, on her own console. Leave her modem on 1,414 until she is off. |
| M-SAR2-SH 06:30 | SH-02 | You, remote from this console. Fiona is outside from 06:29. SH-02 has no unattended-pass sign-off yet; it needs a human. |
| M-SAR2-GW 06:32 | GW-01 | Galway, unattended. Armed by you before you leave the console; checked by you when you are back, before it sets at 06:41. |
Pass Plan
Section titled “Pass Plan”Galway horizon (5° mask)
Section titled “Galway horizon (5° mask)”| Contact | AOS | Rise az | Max Elevation | LOS | Track |
|---|---|---|---|---|---|
| MERIDIAN-SAR-1 #1 | 06:18:00 | 143° | 30.5° at 06:22:47, 716 km | 06:27:33 (az 355°) | Northbound, 9.5 min |
| MERIDIAN-SAR-2 #1 | 06:32:00 | 006° | 25.2° at 06:36:43, 823 km | 06:41:22 (az 224°) | Southbound, 9.4 min, unattended |
| MERIDIAN-SAR-1 #2 | 07:49:51 | 200° | 18.3° at 07:54:23, 1,021 km | 07:58:58 | Second orbit, P3 |
| MERIDIAN-SAR-2 #2 | 08:04:53 | 341° | 2.1° | 08:09:14 | Graze; below the Galway mask |
Shetland horizon (5° mask)
Section titled “Shetland horizon (5° mask)”| Contact | AOS | Rise az | Max Elevation | LOS | Track |
|---|---|---|---|---|---|
| MERIDIAN-SAR-1 #1 | 06:19:07 | 167° | 72.8° at 06:24:05, 409 km | 06:29:04 (az 344°) | Northbound, 9.9 min, Fiona’s |
| MERIDIAN-SAR-2 #1 | 06:30:00 | 011° | 23.0° at 06:34:38, 879 km | 06:39:17 (az 233°) | Southbound, 9.3 min, yours, remote |
| MERIDIAN-SAR-2 #2 | 08:01:59 | 001° | 4.8° | 08:08:10 | Graze, P3 |
The second-orbit contacts are ninety minutes out. Once the morning passes are worked the scheduler will offer to skip ahead; the skip stops two minutes before the next pass at either site and is refused while a timed step is running. A skip taken before the morning windows are worked forfeits them.
Expected numbers
Section titled “Expected numbers”| Pass | Decode window | Peak C/N |
|---|---|---|
| SAR-1 from Galway, 30° | C/N ≥ 8 dB about 06:20:30 to 06:25:00 | ~11 dB at 06:22:47 |
| SAR-2 from Shetland, 23° | C/N ≥ 7 dB about 06:32:50 to 06:36:20 | ~9.7 dB at 06:34:38 |
| SAR-2 from Galway, 25° (unattended) | C/N ≥ 8 dB about 06:34:30 to 06:38:30; still ≥ 6 dB past 06:39 | ~10 dB at 06:36:43 |
Shetland’s SAR-2 peak is about a decibel under Galway’s for the same bird: 879 km against 823 km, and two degrees lower. Every dB of difference between two sites should be explained by range and elevation.
Fiona’s 73° pass peaks at 409 km. Against Galway’s 716 km that is 20 log(716 / 409) = 4.9 dB less path loss, and almost no atmosphere that steep: about 16 dB at the top before the pedestal has its say. 73° is still tracking on a 10°/s pedestal; the keyhole is the last few degrees to the zenith.
Morning Sweeps
Section titled “Morning Sweeps”Four checks per site, both from this console. SH-02 is checked with Shetland selected in the asset tree; Fiona has not touched her equipment, so its panels show what she has.
| Check | Reads on | Nominal | GW-01 action | SH-02 action |
|---|---|---|---|---|
| Board | Dashboard | Only the RX AGC no-carrier warning (empty sky, not a fault) | Confirm | Confirm. A board with nothing tripped on a remote site says nothing about configuration; the next three checks do. |
| Reference | GPS Timing | GPSDO locked, 9 satellites, holdover clear | Confirm | Confirm; the GNSS antenna up there has been flaky in the wind |
| Receive chain | RX Analysis | LNB 13,100 MHz LO, reference locked, 60 K, thermally stable | Retune modem 1 from 1,370 to 1,414 MHz; analyzer centre 1,389 MHz, span 2 MHz | Read the LNB. Leave modem 1 on 1,414; it is Fiona’s SAR-1 carrier until 06:29 |
| Transmit chain | TX Chain | BUC on external reference, current normal, under 70 °C; HPA output disabled | Confirm cold: powered, locked, disabled | Confirm cold |
Link Parameters
Section titled “Link Parameters”LNB high-side at both sites: IF = LO − RF (13,100 MHz LO).
| Signal | RF (MHz) | IF (MHz) | Format |
|---|---|---|---|
| SAR-1 imagery downlink | 11,686 | 1,414 | QPSK 3/4, 36 MHz |
| SAR-1 telemetry beacon | 11,711 | 1,389 | CW |
| SAR-2 imagery downlink | 11,730 | 1,370 | QPSK 3/4, 36 MHz |
| SAR-2 telemetry beacon | 11,703 | 1,397 | CW |
All passes are receive-only. The delivery standard is 8 dB or better held with the modem locked on a Galway-class pass; Shetland’s lower SAR-2 pass is held at 7 dB. Digital links are a cliff, not a slope: above threshold the frames are the frames.
Equipment Status at Turnover
Section titled “Equipment Status at Turnover”GW-01 Galway
Section titled “GW-01 Galway”| Equipment | Status | Notes |
|---|---|---|
| 4 m Ku tracker | Powered, manual, parked az 5° / el 3° | Program-track slews to the 143° rise; SAR-2 is armed on program-track before you leave |
| LNB | 13,100 MHz LO, reference locked | Stable |
| GPSDO | Locked, 9 satellites | Verify, do not assume |
| RX modem 1 | 1,370 MHz / 36 MHz / QPSK 3/4 | Evening shift’s SAR-2 carrier. Retune to 1,414 for the collect; back to 1,370 to arm SAR-2 |
| Spectrum analyzer | 1,414 MHz centre, 60 MHz span | Move to the SAR-1 beacon, 1,389 MHz, 2 MHz span |
| BUC / HPA | No drive / output disabled | No uplink tasking this shift |
| Contact Plan console | Six contacts, none allocated | Reads UNALLOCATED |
SH-02 Shetland
Section titled “SH-02 Shetland”| Equipment | Status | Notes |
|---|---|---|
| 4 m Ku tracker | Powered, manual, parked az 5° / el 3° | Fiona program-tracks SAR-1 from 06:19; you program-track SAR-2 from 06:29 |
| LNB | 13,100 MHz LO, reference locked | Stable |
| GPSDO | Locked, 9 satellites | Confirm from here |
| RX modem 1 | 1,414 MHz / 36 MHz / QPSK 3/4 | Fiona’s. Retune to 1,370 MHz after 06:29, not before |
| Spectrum analyzer | 1,414 MHz centre, 60 MHz span | Move to the SAR-2 beacon, 1,397 MHz, after 06:29 |
| BUC / HPA | No drive / output disabled | No uplink tasking |
Shift Checklist
Section titled “Shift Checklist”Galway sweep (06:00 – 06:07)
Section titled “Galway sweep (06:00 – 06:07)”- Brief read; six contacts, who flies what, and the plan rule understood
- Dashboard: only the RX AGC no-carrier warning on GW-01 (noise only, empty sky); no faults
- GPS Timing: GW-01 GPSDO locked, not in holdover
- RX Analysis: LNB 13,100 / stable; modem 1 to 1,414 MHz; analyzer 1,389 MHz, 2 MHz span
- TX Chain: BUC on reference, current normal, HPA output disabled
The plan (06:07 – 06:10)
Section titled “The plan (06:07 – 06:10)”- M-SAR1-GW and M-SAR2-GW on GW-01; M-SAR1-SH and M-SAR2-SH on SH-02; reads DECONFLICTED
- Second-orbit contacts: decision made, either way
Shetland sweep (06:10 – 06:17)
Section titled “Shetland sweep (06:10 – 06:17)”- SH-02 selected; Dashboard: only the RX AGC no-carrier warning, no faults
- GPS Timing: SH-02 GPSDO locked, not in holdover
- RX Analysis: SH-02 LNB 13,100 / stable; modem left on 1,414
- TX Chain: SH-02 BUC on reference, under 70 °C; HPA output disabled
SAR-1 from Galway (06:18 – 06:27)
Section titled “SAR-1 from Galway (06:18 – 06:27)”- GW-01 selected; program-track MERIDIAN-SAR-1; beacon on RX analysis
- Modem locked on 1,414 MHz, C/N ≥ 8 dB through culmination
Arm Galway, take Shetland (06:23 – 06:30)
Section titled “Arm Galway, take Shetland (06:23 – 06:30)”- GW-01: modem 1 to 1,370 MHz; program-track target MERIDIAN-SAR-2
- 06:29, SH-02 selected: modem 1 to 1,370 MHz; analyzer centre 1,397 MHz
- SH-02 program-track MERIDIAN-SAR-2; imagery carrier on Shetland’s RX analysis
SAR-2 from Shetland (06:30 – 06:39)
Section titled “SAR-2 from Shetland (06:30 – 06:39)”- SH-02 modem locked on 1,370 MHz, C/N ≥ 7 dB through culmination (06:34:38)
Back to Galway (06:37 – 06:41)
Section titled “Back to Galway (06:37 – 06:41)”- GW-01 selected before 06:41: pedestal program-track locked on SAR-2, modem locked, C/N ≥ 6 dB on the way down
After LOS
Section titled “After LOS”- Morning report and customer status to Erik: what was captured, what is committed, what is best-effort
End of Briefing
Section titled “End of Briefing”Nobody built this plan for you and nobody is going to check it before Fiona flies her half of it. The sweeps are the difference between a plan and a hope; the plan is the difference between two sites and one; and the unattended pass is the difference between a network and two consoles.
Erik wants one sentence at 06:42. Make sure it is true.
Good luck.