SMC/Watch Duties

1

SAROPSSearch And Rescue Optimal Planning System

SMC/Watch Duties, Rescue 21, Etc.

J. R. Frost

U. S. Coast GuardOffice of Search and Rescue (CG-534)

2

SMC/Watch Duties

• SAR, especially Search, is HARD—not easy• “Information Sparse” Environment• Aggressive Pursuit

– Use All Available Information—What Does It All Mean?– Investigate, Investigate, Investigate– Follow Lines of Evidence– Think “Outside the Box”– Keep Facts Separate From Assumptions– Avoid “Scenario Lock” and “Scatterbrained” Ideas– Take the Survivor’s Side– Do Not Give Up Easily—ACTSUS Tough Decision

3

Rescue 21

• FM “Lock-on” Properties

– Audio Files—Squelch Broken to Not Broken

– Strongest Signal at Receiver Always “Wins”

– Voice Signals From Multiple Transmitters & Directions May Be In The Same Audio File

• Tropospheric Ducting– Can Cause “Over The Horizon” Reception

From Very Distant Transmitters

4

Rescue 21Voice vs. DF Reception

• RFF DF Antenna Configurations & Heights– Top Mount vs. Side Mount– DF Receive Usually Above Voice Receive– Voice Receive Antenna Is “High Gain”

• Pre-Amplifier Between Antenna & Receiver

– DF Receive Antenna Is “Low Gain”• No Pre-Amplifier Between Antenna & Receiver

– Voice & DF Reception Ranges Are Usually About The Same

– Antenna Heights Are Tabulated

5

Rescue 21Voice/DF Correlation

• Voice & DF Sub-systems Independent

• Voice & LOB Are Correlated When Both Sub-systems Receive A Signal—– At The Same RFF

– On The Same Frequency

– At The Same Time

• Cannot Absolutely Guarantee Each Sub-system Is “Hearing” Same Transmitter– R21 Does Not “Fingerprint” Transmitters

6

Rescue 21What Does It All Mean?

• LOBs Must Always Be Evaluated For:– Relevance

• Does The Associated Audio File Contain Signals From Multiple Sources?

• If Multiple LOBs, Which Go With Which Signal?• Do The LOBs Make Sense In Light Of Other

Information, Including Range Rings?

– Reliability• Direction Relative To Tower for Side-Mount DF

Antennas• Signal Quality

7

Rescue 21What Does It All Mean?

R21 Best VHF-FM System Yet

BUT…

R21 IS NOT INFALLIBLE!

8

Actual R21 Mayday Sector Charleston

MISLE Case #520353

040954Q SEP 10

“Jacksonville… Mayday, Mayday, Mayday. We are going down off the coast of … Captain Bulldog, this is Coast Guard Sector Jacksonville, over…and a half miles out. Thirty-eight foot Fountain. If we…Maritime Center, Maritime Center, this is Hood. Do you read me?”

9

10

Mayday Call Heard Only On Mt Pleasant RFF

11

First LOB (259T) Found That Was Associated With Audio File

12

Second LOB (213T) Found That Was Also Associated With Audio File

13

Scenario Based on 213T LOB

14

A-1 (Helo), B-1 (Helo), B-2 (Boat) Completed with NEGRESPOS for 38-ft Boat = 99%, POS for PIW w/o PFD = 21%

ACTSUS 041849Q SEP 10

15

Actual R21 Mayday Sector Charleston

MISLE Case #520353

• Why NEGRES?– Failure To Detect Search Object That Was

Present In The Areas?– No Detectable Search Object Present In The

Areas?– Searching In The Wrong Place?

• Why ACTSUS Less Than 9 Hours After Distress Broadcast?– About one hour before sunset

16

Mt Pleasant Reception Range For 30-ft Transmitter Antenna

17

Mt Pleasant & Port Royal Reception Ranges For 30-ft Transmitter Antenna

18

Mt Pleasant, Port Royal & McClellanville Reception RangesFor 30-ft Transmitter Antenna

19

30-ft Reception & Radio Horizon Rings For All Three RFFs

20

Range Ring AnalysisSee USCG Addendum 3.4.15.3(a)(3)c and 3.4.15.3(a)(4)c.

21

LOB & Range Ring Analysis ScenariosSee USCG Addendum 3.4.15.3(a)(3)c and 3.4.15.3(a)(4)c.

22LOB Scenario Weight = 1 (Very Unlikely)

Range Ring Analysis Scenario Weight = 10 (Almost Certain)

23SAROPS Search Plan for 1 Hour After Mayday

Conditional POS: 38-ft Cuddy Cabin 73%, Swamped 36%, PIW 5%

24Distress Incident Position 041000Q SEP 10

(Reconstructed From Survivor Debrief)

25Capsized Boat, 7 Survivors Located and Rescued 050600Q SEP 10

(4 Adults, 3 Children, Ages from 5 to 62. Adrift 20 Hours.)

26Case had been re-opened based on overdue report from wife of O/O

042206Q SEP 10. Searches conducted thru the night.

27

SAROPSCorrecting Frequent User Errors

• TIME Issues– SAROPS Is A Time-Based Simulation

– Tip: When Adding SRUs, Move Time Slider To Desired CST If Not Already There.

– Tip: Searches May Be Planned For Any Period of Time Contained Between Drift Start Time and SIM End Time + 12 Hours Without Re-running SIM.

– Always Use Planner! It Helps Avoid Errors From Time Mismatches, Eases Tracking Of Previous Searches.

– Avoid Using “Patterns Tool” Outside of “Runs.”

28

29


• Uncertainty Issues– Zero Position Error Is Never A Good Idea.

– Very Small Position Error Is Usually Not A Good Idea.

– Zero Time Error Is Often Not A Good Idea.

– Non-zero Default Uncertainties for Positions (1.0 NM Probable Error) and Times (+/- 1.0 Hours) Are Coming.

30


• Search Planning Epochs– Change Search Epochs (Go To Subsequent

Search) At Day/Night Boundaries, or

– Change Search Epochs Every 12 Hours, or

– Change Search Epochs When Desired.

– Avoid Search (Pattern) Assignments That Contain Sunset or Sunrise Whenever Feasible.

– New Interactive Planner Will Address Many Planning Issues Now Handled Awkwardly.

31


• Search Object Types – Use Multiple Search Object Types Initially As

Appropriate, Not Always Just One.

– Do Not Wait For Searches For Larger Search Objects To Fail Before Considering Smaller Search Objects.

– Adjust Search Object Type Weights To Reflect Relative Likelihood Of Each Type

– Use Check Boxes On SRU Properties Screen To Force Optimization Of Searches For Search Objects At Highest Risk.

32

33


• Search Object Types (Continued) – Leeway Is Important!

• Choose Search Object Types Carefully

• Leeway Differences Will Eventually Separate Objects By Type

– Detection Properties (Primarily Size) Are Important!

• Choose and Enter Dimensions Carefully

• Get Actual Dimensions Whenever Feasible

• Adjust Dimensions for Swamped/Capsized Boats (Next Version of SAROPS Will Provide Automatic Adjustment)

34

35

36

37


• Environmental Data– Deploy SLDMBs Early And Often!

• The Only Wasted SLDMBs Are The Ones Not Used!

• “Activate” Deployed SLDMBs

• Use SLDMB Trajectories To Select Best EDS Surface Current Product

– Edit Area of Interest (AOI)

• Default AOI Buffer Is Generous—Reduced Dimensions More Appropriate In Most Cases

• At Tools>Options>SAROPS>Run Parameters, Adjust AOI Buffer Speed Down To 2 or Even 1 Knots As Search Extends Beyond One Day (24 Hours)

38

39


• Save & Export Cases Early & Often• Get Help Earlier Rather Than Later

– Small Problems Tend to Compound

– SAROPS Help Desk, CG-534

• Practice, Practice, Practice– General Proficiency

– Learning What SAROPS Can Do

– Learning More About How SAROPS Works

40

SAROPSScenario Review

• Scenario Definition: Description of events up to and including the possible distress incident positions and times.

• Scenario Analysis & Development Is A Critical Success Factor!

• Last Known Position (LKP)– Distress Incident Position & Uncertainty– Distress Incident Time & Uncertainty

41


• LKP + Dead Reckoning (LKP + DR)– Distress Incident Time Known (No Uncertainty)

– Previous Position/Time & Uncertainty For Each

– Course/Speed & Uncertainty For Each Since Previous Position

• Area– Bounded Region Containing Distress Incident

– Distress Incident Time & Uncertainty

42


• Voyage– Must be Complete From a Place of Safety to a Place

of Safety– Each “Particle” Given Its Own Unique Voyage Plan– Ordered List of Positions and Areas Connected by

Transit Legs with Min, Cruise, and Max Speeds– Loiter or “Dwell” Times & Uncertainties Allowed at

All Intermediate Locations – Distress Occurs After Departure, Before ETA– Loitering at Departure and Destination (“Safe”)

Locations NOT Allowed

43


• New Line of Bearing (LOB)– Statistical Distribution of Distress Incident Positions

Based On Bearing Uncertainty and Minimum and Maximum Ranges from Observer’s Position

– Ellipses for R21 “Fixes” (a.k.a. “Areas of Uncertainty”)

• New Flare– Bounded Region (“Area”) Containing Estimated

Location of an Observed Flare’s Source

– Bounds are Based on Min/Max Bearings & Min/Max Ranges from Observer’s Position

44

SAROPS TEAM U.S. Coast Guard

CG-534 CG-761 CG-64 C3CEN OSC National SAR School R&DC

Contractors

Northrop Grumman Metron Applied Science Associates

Other Federal

USN NOAA NGA

Thank you!Questions?

J. R. [email protected]

+1 202-372-2081

Documents

SMC/Watch Duties