Status – U.S. Maritime Backup Issues

• Session 2 , 28 October 2002– Status & Plans of LORAN-C Service Providers

31st Annual Convention & Technical

Symposiumof the

International LORAN Association

Crowne Plaza Washington National Airport

Status – U.S. Maritime Backup Issues

• FY2002 U.S. LORAN-C Performance– LCDR Max Caruso, USCG

NAVCEN Western Operations Officer

• Synchronization to UTC

– Gene SchlechteNAVCEN Operations Planning Division

• Maritime Backup Assessment– CAPT Curtis Dubay, USCG

NAVCEN Commanding Officer

FY02 LORAN-C Performance

A year of recapitalization and system modernization

FY02 LORAN-C Performance

• LORAN-C Availability Review for the Period 1 October 2001 to 1 October 2002

• The LORAN Operations Information System (LOIS 2 NT) was used to generate this report

• LT Bob Berger and CWO Scott McDonald, NAVCEN LORAN Planning Branch provided the data analysis

LORAN-C AVAILABILITY FY02

99.46% 99.82% 99.95% 99.89% 99.90% 99.95% 99.88% 99.87% 99.84%

98.00%98.20%98.40%98.60%98.80%99.00%99.20%99.40%99.60%99.80%

100.00%

GOA-7960 SEUS-7980

NOCUS-8290

GLKS-8970

SOCUS-9610

USWC-9940

NEUS-9960

NORPAC-9990

LORAN-CTOTALFY02

Tok NC SC PC

LOIS DATA GOA 7960 Oct 1, 01 – Oct 1, 02

GOA (7960) Availability FY0299.46%

93.00%

93.50%

94.00%

94.50%

95.00%

95.50%

96.00%

96.50%

97.00%

97.50%

98.00%

98.50%

99.00%

99.50%

100.00%

M-Tok

X-Narrow Cape

Y-Shoal Cove

Z-Port Clarence

FY TOTAL

SEUS (7980) Availability FY0299.82%

98.00%

98.20%

98.40%

98.60%

98.80%

99.00%

99.20%

99.40%

99.60%

99.80%

100.00%

M-Malone

W-Grangeville

X-Raymondville

Y-Jupiter

Z-Carolina Beach

FY TOTAL

NOCUS (8290) Availability FY0299.95%

99.00%

99.20%

99.40%

99.60%

99.80%

100.00%

M-Havre

W-Baudette

X-Gillette

Y-Williams Lake (CCG)

FY TOTAL

0

50

100

150

200

Equipment Communication Personnel Natural Power Catastrophe Authorized

Rate: 8290 NOCUS 01 Oct 2001 to 01 Oct 2002

Minu

tes

M-Havre

V

W-Baudette

X-Gillette

Y-WilliamsLake

Z

NOCUS (8290) UUT by Cause

GLKS (8970) Availability FY0299.89%

98.00%

98.20%

98.40%

98.60%

98.80%

99.00%

99.20%

99.40%

99.60%

99.80%

100.00%

M-Dana

W-Malone

X-Seneca

Y-Baudette

Z-Boise City

FY TOTAL

0

100

200

300

400

500

600

700

800

900

Equipment Communication Personnel Natural Power Catastrophe Authorized

Rate: 8970 GLKS 01 Oct 2001 to 01 Oct 2002

Minu

tes

M-Dana

V

W-Malone

X-Seneca

Y-Baudette

Z-BoiseCity

GLKS (8970) UUT by Cause

SOCUS (9610) Availability FY0299.90%

98.50%

98.80%

99.10%

99.40%

99.70%

100.00%

M-Boise City

V-Gillette

W-Searchlight

X-Las Cruses

Y-Raymondville

Z-Grangeville

FY TOTAL

0

100

200

300

400

500

600

700

800

Equipment Communication Personnel Natural Power Catastrophe Authorized

Rate: 9610 SOCUS 01 Oct 2001 to 01 Oct 2002

Minu

tes

M-BoiseCity

V-Gillette

W-Searchlight

X-LasCruces

Y-Raymondville

Z-Grangeville

SOCUS (9610) UUT by Cause

USWC (9940) Availability FY0299.95%

98.00%

98.20%

98.40%

98.60%

98.80%

99.00%

99.20%

99.40%

99.60%

99.80%

100.00%

M-Fallon

W-George

X-Middletown

Y-Searchlight

FY TOTAL

0

50

100

150

200

250

300

Equipment Communication Personnel Natural Power Catastrophe Authorized

Rate: 9940 USWC 01 Oct 2001 to 01 Oct 2002

Minu

tes

M-Fallon

V

W-George

X-Middletown

Y-Searchlight

Z

USWC (9940) UUT by Cause

NEUS (9960) Availability FY0299.88%

98.00%

98.20%

98.40%

98.60%

98.80%

99.00%

99.20%

99.40%

99.60%

99.80%

100.00%

M-Seneca

W-Caribou

X-Nantucket

Y-Carolina Beach

Z-Dana

FY TOTAL

0

200

400

600

800

1000

1200

1400

Equipment Communication Personnel Natural Power Catastrophe Authorized

Rate: 9960 NEUS 01 Oct 2001 to 01 Oct 2002

Minu

tes

M-Seneca

V

W-Caribou

X-Nantucket

Y-CarolinaBeach

Z-Dana

NEUS (9960) UUT by Cause

NORPAC (9990) Availability FY0299.87%

97.00%

97.20%

97.40%

97.60%

97.80%

98.00%

98.20%

98.40%

98.60%

98.80%

99.00%

99.20%

99.40%

99.60%

99.80%

100.00%

M-ST. Paul

X-Attu

Y-Port Clarence

Z-Narrow cape

FY TOTAL

0

200

400

600

800

1000

1200

Equipment Communication Personnel Natural Power Catastrophe Authorized

Rate: 9990 NORPAC 01 Oct 2001 to 01 Oct 2002

Min

utes

M-St.Paul

V

W

X-Attu

Y-PortClarence

Z-Narrow Cape

NORPAC (9990) UUT by Cause

99.46% 99.82% 99.95% 99.89% 99.90% 99.95% 99.88% 99.87% 99.84%

98.00%

98.20%

98.40%98.60%

98.80%

99.00%

99.20%

99.40%99.60%

99.80%

100.00%

GOA-7960 SEUS-7980

NOCUS-8290

GLKS-8970

SOCUS-9610

USWC-9940

NEUS-9960

NORPAC-9990

LORAN-CTOTALFY02

FY02 LORAN-C AVAILABILITY

99.46% 99.95% 99.97% 99.96% 99.96% 99.97% 99.98% 99.88% 99.89%

98.00%

98.20%

98.40%98.60%

98.80%

99.00%

99.20%

99.40%99.60%

99.80%

100.00%

GOA-7960 SEUS-7980

NOCUS-8290

GLKS-8970

SOCUS-9610

USWC-9940

NEUS-9960

NORPAC-9990

LORAN-CTOTALFY02

FY02 AVAILABILITY (less AUTM)

FY02 AVAILABILITY (less AUTM & Solar)

99.978%99.979%99.981%99.970%99.965%99.983%99.957%99.995% 99.98%

98.000%

98.200%

98.400%98.600%

98.800%

99.000%

99.200%

99.400%99.600%

99.800%

100.000%

GOA-7960

SEUS-7980

NOCUS-8290

GLKS-8970

SOCUS-9610

USWC-9940

NEUS-9960

NORPAC-9990

LORAN-CTOTALFY02

Status – U.S. Maritime Backup Issues

• FY2002 U.S. LORAN-C Performance– LCDR Max Caruso, USCG

NAVCEN Western Operations Officer

• Synchronization to UTC

– Gene SchlechteNAVCEN Operations Planning Division

• Maritime Backup Assessment– CAPT Curtis Dubay, USCG

NAVCEN Commanding Officer

LORAN Synchronization to UTC

• Time Of Transmission Measurement (TOTM) Project started at LSU in late 1990s

• 1997 - TOTM equipment installed at Williams Lake

• Now - TTM installed at every US Master including the two in Alaska.

LORAN Synchronization to UTC

• US Public Law 100-223, Section 310 requires the control the transmission of LORAN signals to within +/- 100 nanoseconds of UTC at times of coincidence (TOC).

• The Coast Guard has worked with USNO to steer LORAN transmissions to UTC

• USNO monitors & measures LORAN time differences (TD) in far field to determine difference between LORAN Chain & UTC

North American Loran-C System

DESTIN

MIDLAND

WHIDBEY ISLAND

FAIRBANKS

COLD BAY

GEORGE

NARROW CAPE

SHOAL COVE

GILLETE

NANTUCKET

CARIBOU

LSU

GREAT FALLS

GRAND JUNCTION

GRANGEVILLEMALONE

CAROLINA BEACH

MONTAGUE

LUMSDEN

COMFORT COVE

ST. ANTHONY

DUNBAR FOREST

BAUDETTE

HAVRESPOKANE

PORT HARDY

SAND SPIT

JUNEAU

TOK

GALENA

PORT CLARENCE

SPRUCE CAPE

ST. PAULPETROPAVLOVSK, RUSSIA

ALEXANDROVSK, RUSSIA

WILLIAMS LAKE

MEDICAL LAKE

PT. PINOS

NAVCENDETPETALUMA

PT. CABRILLO

MIDDLETOWN

FALLON

SEARCHLIGHT

LAS CRUCES

BISMARK

BOISE CITY

LITTLE ROCK

DANA

NEW ORLEANS

JUPITER INLET

MAYPORT

NAVCENALEXANDRIA

PLUMBROOK SANDY HOOK

CAPE ELIZABETHSENECA

CAPE RACE

FOX HARBOR

RAYMONDVILLE

ATTU

CONTROL SITE

TRANSMITTER STATION

PCMS SITE

USNO Monitor

Time of Transmission System

• Provides a means to monitor Loran transmissions directly at the transmitting antenna.– Eliminates propagation path uncertainties

making +/- 100 nanosecond control possible

Cesium at Master stationsUTC at USNO

Time of Transmission System

GPS Time

TTM Installation at Master Station

-500

0

500

1000

1500

2000

1-A

ug-0

2

5-A

ug-0

2

9-A

ug-0

2

13-A

ug-0

2

17-A

ug-0

2

21-A

ug-0

2

25-A

ug-0

2

29-A

ug-0

2

2-Se

p-02

6-Se

p-02

10-S

ep-0

2

14-S

ep-0

2

18-S

ep-0

2

22-S

ep-0

2

26-S

ep-0

2

30-S

ep-0

2

4-O

ct-0

2

8-O

ct-0

2

12-O

ct-0

2

16-O

ct-0

2

20-O

ct-0

2

24-O

ct-0

2

28-O

ct-0

2

1-No

v-02

5-No

v-02

9-No

v-02

nano

seco

nds

Time Step TTM Freq Adj

SOCUS (9610) TTM Data Plot 15JUL -13OCT 2002

26-Sep-02 0 -14 4.9691512 1946 24 -500 194627-Sep-02 10 -14 4.9832037 1960 25 -490 196028-Sep-02 20 -15 5.0001888 1977 24 -480 197729-Sep-02 40 -15 5.0155024 1992 22 -460 199230-Sep-02 60 -12 5.0206963 1997 22 -440 1997

1-Oct-02 70 -12 -430 NO TTM DUE TO LSU WORKING WITH LCCS2-Oct-02 70 -15 4.5811858 1558 51 -430 15583-Oct-02 4.0339589 1011 21 10114-Oct-02 60 -11 4.0377648 1014 19 -440 10145-Oct-02 80 -13 4.0415557 1018 20 -420 10186-Oct-02 100 -15 4.0468340 1024 21 -400 10247-Oct-02 100 -13 4.0510420 1028 19 -400 10288-Oct-02 90 -12 -410 NO TTM RECAL DONE9-Oct-02 100 -12 5.0608118 2037 20 -400 2037 NEW T1 27.088251

10-Oct-02 110 -12 -390 NO TTM ROUTER INSTALLED11-Oct-02 130 -12 5.0732075 2049 20 -370 204912-Oct-02 150 -13 5.1007104 2077 23 -350 207713-Oct-02 160 -16 5.1086631 2085 22 -340 208514-Oct-02 170 -19 5.1086402 2085 21 -330 208515-Oct-02 5.1316179 2108 20 2108

Cells in red are equations and are to be copied (no data entry).

Date9610

USNOGPST2 MeanTTMTOTM Sigma

Time StepUSNO-TSTOTM-TS

Adj MarkerFreq Adjust/Remarks

SOCUS (9610) TTM Log Sheet

200

-1200

-1100

-1000

-900

-800

-700

-600

-500

-400

-300

-200

-100

0

100

200

15-J

ul-0

2

18-J

ul-0

2

21-J

ul-0

2

24-J

ul-0

2

27-J

ul-0

2

30-J

ul-0

2

02-A

ug-0

2

05-A

ug-0

2

08-A

ug-0

2

11-A

ug-0

2

14-A

ug-0

2

17-A

ug-0

2

20-A

ug-0

2

23-A

ug-0

2

26-A

ug-0

2

29-A

ug-0

2

01-S

ep-0

2

04-S

ep-0

2

07-S

ep-0

2

10-S

ep-0

2

13-S

ep-0

2

16-S

ep-0

2

19-S

ep-0

2

22-S

ep-0

2

25-S

ep-0

2

28-S

ep-0

2

01-O

ct-0

2

04-O

ct-0

2

07-O

ct-0

2

10-O

ct-0

2

13-O

ct-0

2

nano

seco

nds

Time Step TTM Freq Adjust

NEUS (9960) TTM Data Plot 15JUL -13OCT 2002

NEUS (9960) TTM Data Plot 15JUL -13OCT 2002

200

y = 1.3647x - 931.14

-1200

-1100

-1000

-900

-800

-700

-600

-500

-400

-300

-200

-100

0

100

200

15-J

ul-02

18-J

ul-02

21-J

ul-02

24-J

ul-02

27-J

ul-02

30-J

ul-02

2-Au

g-02

5-Au

g-02

8-Au

g-02

11-A

ug-0

2

14-A

ug-0

2

17-A

ug-0

2

20-A

ug-0

2

23-A

ug-0

2

26-A

ug-0

2

29-A

ug-0

2

1-Se

p-02

4-Se

p-02

7-Se

p-02

10-S

ep-0

2

13-S

ep-0

2

16-S

ep-0

2

19-S

ep-0

2

22-S

ep-0

2

25-S

ep-0

2

28-S

ep-0

2

1-Oc

t-02

4-Oc

t-02

7-Oc

t-02

10-O

ct-0

2

13-O

ct-0

2

nano

seco

nds

Time Step TTM-TS Freq Adj Linear (TTM-TS)

= T2 Raw Data Avg + T1 Cal - Pulse Tracking Point - Cable Delays (all in nanoseconds)

= ( 5108.6631+ 27088.251 - 30000 - 112 ) = 2085 nanoseconds

TTM Calculation

• TTM Formula for USCG installation:

• Sample TTM Calculation for NEUS (9960) on 13 October 2002:

Summary of UTC Measured Offsets

• The following offsets have been established utilizing the installed TTM equipment:

– NOCUS (8290-M): +2.3 usec

– NORPAC (9990-M): +2.5 usec

– SOCUS (9610-M): +1.8 usec

– USWC (9940-M): +1.3 usec

– GOA (7960-M): +1.2 usec

– GLKS (8970-M): -0.4 usec

– SEUS (7980- M): +0.1 usec

– NEUS (9960-M): +0.02 usec

Plan to Remove LORAN UTC Offsets

• NAVCEN is planning to time step one chain per week– starting with the West Coast Chains– then East coast chains – last will be the two Alaskan chains

• We will send advance user notice before a Chain time step

• We Plan to insert one time step for each chain on a Tuesday at 0900 Local time

• The time step amount (in microseconds) will be included in the user notice

• This process is considered to be the least problematic for the timing/legacy user.

USCG LORAN TTM Contacts

• Navigation Center (Operations Planning)– LT Bob Berger, RBerger@navcen.uscg.mil

• LORAN Support Unit (Technical)– Mike Campbell, MCampbell@lsu.uscg.mil

• Program Manager’s Staff (Policy)– LCDR John Merrill, JMerrill@comdt.uscg.mil

Status – U.S. Maritime Backup Issues

• FY2002 U.S. LORAN-C Performance– LCDR Max Caruso, USCG

NAVCEN Western Operations Officer

• Synchronization to UTC

– Gene SchlechteNAVCEN Operations Planning Division

• Maritime Backup Assessment– CAPT Curtis Dubay, USCG

NAVCEN Commanding Officer

Maritime Assessment

Volpe Study shows vulnerability of GPS

Maritime modes concur

Current infrastructure satisfactory

E-navigation poses growing vulnerability

Maritime Assessment

Future vision – “System of systems” that incorporates adequate backups

Conventional navigation capability,

Regulatory procedures,

Development of alternate “e-inputs”

Maritime Assessment

Two Safety Critical Applications

Harbor, harbor approach, and constricted waterways

• Total reliance on DGPS is a concern

Automatic Identification System (AIS)

• Positioning and timing are concerns

Maritime Assessment

Comments on Study Recommendations Continue LORAN-C modernization

• Assess capabilities of “enhanced LORAN”

Certification of GPS receivers• By July 2002, a maritime certification program will be in

place under SOLAS

• USCG participation in domestic and international standards setting bodies

Maritime Assessment

Backup System Initiatives

Leverage FAA’s LNAV LORAN study

Partner with industry to analyze enhanced LORAN capabilities

Develop & assess integrated maritime receiver technology

Status – U.S. Maritime Backup Issues

• Session 2 , 28 October 2002– Status & Plans of LORAN-C Service Providers

31st Annual Convention & Technical

Symposiumof the

International LORAN Association

Crowne Plaza Washington National Airport