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1 INTRODUCTION

On the morning of 1 October 2015, the U.S.-flagged

containership El Faro foundered and sank

approximately 40 nautical miles northeast of Acklins

and Crooked Island, Bahamas, while sailing close to

er Research and Development Center, Vicksburg, Mississippi, United States

U.S. National Transportation Safety Board’s (NTSB) recommendations was for the National Oceanic and

Atmospheric Administration (NOAA) to explore increasing the collection of weather data from ships in order

Most commercial ships (in particular those subject to the International Maritime Organization's (IMO) Safety of

Life and Sea (SOLAS) convention) have a Class A AIS transceiver installed to comply with mandatory carriage

requirements. Many vessels not required to carry AIS equipment voluntarily install AIS transceivers (either

Class A or B). All of these AIS transceivers (except for the Class B “CS”) can be used to transmit an AIS message

8 (broadcast binary message) by sending the transceiver an appropriately formatted NMEA sentence (BBM).

Weather data can be embedded in an AIS application-specific message (ASM) carried by the AIS message 8 and

automatically transmitted by the ship. This transmission can be received by terrestrial AIS stations (when in

range) or by satellite AIS receivers. The AIS weather data can then be converted into the appropriate format and

of use to other researchers monitoring climate change or other environmental factors. By leveraging this

equipment aboard the ship transmitted weather data at 3-minute intervals. Several different ASM formats were

tested, including two developed specifically for this test to improve satellite reception. This report will discuss

the concept, the demonstrations, and the results to date including the efficacy of the various ASM formats.

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possible weather forecasts and advisories to keep

mariners safe" and included the following

recommendation addressed to the National Oceanic

and Atmospheric Administration (NOAA):

Coordinate with the National Weather Service, vessel

operators, automatic identification system (AIS) service

providers, and required onboard technology vendors to

metadata, by satellite and land-based receivers, to global

meteorological authorities via the Global

Telecommunication System with acceptable time delay.

component of the World Meteorological Organization

However, this data is submitted infrequently,

typically four times per day and is primarily a manual

automate and increase the frequency of data submittal

application that receives sensor data and converts it

the ship's installed AIS transceiver.

collision avoidance, provision of vessel traffic services

from shore authorities, and allowing coastal states to

including weather, water levels, lock queues,

navigation restrictions, etc. [8-10]. It could also be

used to transmit weather information from ship to

shore.

2 AIS WEATHER TRANSMISSIONS CONCEPT

There are three main components needed on the ship

to generate and send an AIS weather message:

1 A source of weather data presented in a

recognized industry standard.

2 An AIS transceiver.

database.

This complete system is shown in Figure 1.

The best source of real-time weather data is from a

digital weather station because it generates the data

automatically at up to a 1 Hz interval. There are

numerous commercial options on the market that

measure barometric pressure, wind (speed and

wind speed and direction, pressure, air temperature,

TurboWin sentences via a USB connection. The

weather station data can be directly read by a

computer process and converted into an AIS message.

Data from the weather station can be accumulated

(averaged) and sent automatically without mariner

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Most commercial ships (in particular those subject

to the International Maritime Organization's (IMO)

Class A AIS transceiver [13] installed to comply with

running on the same computer as TurboWin, or if

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Monitor process running on a computer at Alion

parsed and put into a text file (see Figure 8).

Some lessons learned from this initial prototype:

− The system worked as planned.

− The installation of the weather station and laptop

− We found that the ship's pilot port was not

correctly wired. This is a common problem

part of the connection so any installation needs to

be prepared for the possibility that the wires are

reversed. It might be worth creating an inline wire-

types of errors in the future.

9) during their winter cruise from 12 January through

manually entered weather data from ship;

− demonstrate the ability to receive the data from

terrestrial and satellite receivers; and

− demonstrate the ability to decode and save the

data in various formats.

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to the ship's AIS Class A transceiver via the pilot port

for transmission every three minutes. The software

creating the messages created a log file of every

and whether the transmission from the ship's

within range. The USCG provides the U.S. Army

Corps of Engineers (USACE) with a live feed of their

data; this was filtered to only collect messages

logged and parsed to extract the weather observation

of the data they received from TS Kennedy. Another

Table 1) to assess the differences between them. These

three ASMs are all part of existing standards. Mid-

were transmitted along with the initial three.

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Figure 12 shows the locations of all transmissions

from the KENNEDY. The ship regularly transmitted

message 1s are plotted as yellow •s (but not visible at

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the entire cruise, and are plotted as black •’s.

intervals. These are indicated in Figure 12 with the

the southbound transit where the software was not

zoomed in on the ship's track north of Cuba, the

different reports are more visible (except for the red

and magenta + which are under the black +).

1

Typically message 27s would not be transmitted within range of a

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message 3’s were received at a higher percentage

(though still low). After consultation with the satellite

AIS message 27 was the best by far; this is because

these messages are only 96 bits long and more

importantly, are transmitted on two different VHF

AIS traffic on channels AIS1 and AIS2.

we determined that we had also been receiving some

messages via terrestrial receivers, which skewed these

received via satellite). We also discovered that due to

duplicate message 27s; these duplicates have been

Table 3 and Table 4 were calculated.

5 CONCLUSIONS

It is clear from the data reviewed thus far from this

messages is less data. The largest message (ASM FI

33) carries the most met/hydro data and also has time

stamps for each data element allowing for the most

information transfer. This message however, does not

noted that although the percentage of messages

vessel would typically send (i.e., 4).

6 RECOMMENDATIONS/FUTURE

position from the AIS message 27s.

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− Additional ship testing is planned, using a larger

reception on trans-oceanic voyages may also

increase satellite reception for multi-slot messages,

commercial vessels

− Gathering feedback and concerns from vessel and

shipping company personnel

− Gathering more data to test reception from other

terrestrial and satellite sources

− For the additional ship testing, a small embedded

processor will be used to assess the feasibility of

REFERENCES