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, [email protected]
• LORAN Support Unit (Technical)– Mike Campbell, [email protected]
• Program Manager’s Staff (Policy)– LCDR John Merrill, [email protected]
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