SURVEY NEWS FROM SONARDYNE
In search of
Liberty Bell 7
The mission to find NASAs
missing space capsule
EHF or MF:
Its your choice Pharos
The new light in
Photograph courtesy of The Discovery Channel
Towing the line
New transponder aids long-range towfish tracking
In search of Liberty Bell Why Big
They said it would never be found. But 38 years after it sank on splashdown,
and with the help of the latest acoustic positioning technology from Sonardyne,
NASAs Liberty Bell 7 space capsule has been recovered.
It was discovered sitting
upright on the sandy seabed 3 The exceptional performance
miles below with, to the team’s of the Big Head USBL
amazement, a discarded Coke transceiver is due to its unique
can lying a few feet away. ability to listen downward or
beind the surface vessel. This
Capsule recovery took some enables it to avoid signal
eight hours of slow and interference from the surface
Photograph courtesy of The Discovery Channel vessel itself and to focus
cautious lifting during which
attention on incoming signals
the Big Head USBL transceiver
from the seabed below or
T he spacecraft had
been lying in 16,000 ft of
water some 300 miles off Cape
meant that the system had to
delivered to the survey team
within ten days.
tracked the ROV acoustically
by providing range and
bearing between the surface
In doing so, a very high signal
Canaveral having flooded ship and a Sonardyne 7823 to noise ratio can be achieved,
moments after astronaut Virgil Capsule Recovery transponder on the vehicle. allowing operators to work in
“Gus” Grissom had been The capsule’s recovery deeper water and in many
winched to safety. followed a towfish scan of a “We acoustically cases, using their existing
24 square mile search grid tracked a depres- inventories of transponders.
which identified eighty
In an expedition funded by sor in 16,000 ft – I Big Head is now in use for
The Discovery Channel, possible seabed targets. The
first one to be investigated by
don’t think that deep ROV and long range
Oceaneering International Inc.
in Houston was contracted to
has ever been towfish tracking (See Page 4).
conduct the search and recovery done before”.
and a two man team from John
Reviewing the system’s
E. Chance & Associates; Chris
performance after the event, To mark the introduction of Son
Gladwin and Brad Chaumont,
were sub-contracted to provide
the John E. Chance surveyors COMPATT transponder, an in-w
were enthusiastic. “I was
the necessary survey and frequency capabilities was rece
really happy with the
Sonardyne Big Head USBL
Because of the extreme water
transceiver and the high
power transponder,” said
T he new transponder,
Type 7901, integrates
the long range capabilities
depths, Sonardyne’s recently
Chris Gladwin “the system
launched “Big Head” USBL
Photograph courtesy of The Discovery Channel
(upto 3kms) of the MF band
Ocean Explorer 6000 side-scan
never missed a beat.”
transceiver was supplied as the with the higher accuracy
sonar search vehicle used to locate
best acoustic solution for the Magellen 725 ROV
Liberty Bell 7 (±5cm) of EHF equipment, in
Brad Chaumont was equally
providing the precise ROV a single subsea housing that
pleased; he added “The
positioning demanded by the though, proved to be the is only slightly longer than a
Sonardyne system worked
project. Tight deadlines also historic 8-foot tall Liberty Bell conventional Mk4 COMPATTS
Pharos Lite is the first product to be released from Sonardynes next generation
acoustic navigation software development program. Pharos Lite has been
designed for basic Long Baseline (LBL) tracking projects and can be used to
track simultaneously a single ROV and a surface support vessel.
Pharos is the result of a Pharos Lite post operation analysis.
major investment by Pharos Lite is the basic LBL Position data can also be
Sonardyne. Aimed at navigation version with features passed to other navigation
achieving a generic approach that include; baseline systems in ASCII format
to navigation software, it is calibration, single ROV using a serial port.
being presented as a family tracking and data logging.
of software building blocks Survey and Construction
that can be used to construct The intermediate and calibration methods such as
advanced software systems Grid-on-Grid and single
a wide range of tracking and
are called Pharos Survey and transponder Box-In are also
Pharos Construction. supported.
The system has been Pharos Survey is able to track
Pharos Construction is
designed to ensure compatibility
Job Configuration Display designed for large offshore
with all current and planned
Operators can monitor all construction and field
Sonardyne acoustic transceivers
measured acoustic ranges, development projects where
and beacons in addition to
the position quality at each field wide arrays are required
other positioning sensors. to track multiple subsea
update and any alarms
generated by the system via vehicles at the same time.
There will be three versions a series of text displays. All Navigation Display
of Pharos for the offshore measured and calculated two subsea vehicles in the Pharos Construction will be
survey and construction data, alarms and events are same navigation cycle and the total field development
markets with Pharos Lite logged to a single log file support up to 14 beacons in an solution when combined with
being the first to be released. which can be replayed for array. Additional array Sonardyne LBL hardware.
nch for Dual Band COMPATT the system’s ability to function
in both frequencies simultaneously.
nardynes new Dual Band The launch event was held This brings the potential benefit
of providing positioning for a
onboard Swire’s Pacific
water demonstration of its multi- An acoustic shield to overcome
Buccaneer in Aberdeen Harbour. ship’s DP control while enabling
ently held in Aberdeen subsea tasks that need the
the effects of ROV noise on
the performance of remote LBL
The demonstration showed higher accuracy to be conducted
transceivers is now available.
how the transponder could be at the same time in EHF.
calibrated in MF, which gives
the range necessary for The Sonardyne shield rejects
The versatility of the new dual noise interference coming
deepwater operations, but
band COMPATT can also be from below ROV-mounted
could also provide precise
valuable when working in busy transceivers in favour of
seabed positioning in EHF.
It is depth rated to 2,500 areas when two vessels may transponder signals from the side.
metres and has a fully Several of the visitors who need to complete tasks using This results in longer ranges
instrumented endcap with release. attended were impressed by the same array at the same time. and more stable positioning.
Towing the Line Office
Enabling towfish to be more effectively positioned on deepwater surveys has Information
been a growing problem. New tracking techniques and transponders, used Head Office
recently on a Mediterranean survey, are helping to provide a solution. International Ltd.
Traditionally, when a towfish Blackbushe Business Park,
has been used in deepwater, Yateley, Hampshire,
GU46 6GD, UK
the long layback has meant
Tel: +44 (0)1252 872288
that accurate acoustic positioning Fax: +44 (0)1252 876100
has only been possible by Email: firstname.lastname@example.org
deploying a chase boat to sail
above the towfish. Sonardyne
This can be quite costly, so when In addition, a ‘cut-down’ (Below) The ‘cutdown’ 7823 was Unit 14, Claymore Drive,
used in Responder mode to enable Bridge of Don, Aberdeen,
Gardline Surveys approached version of a Sonardyne’s Type fast position updates of the ROTV. AB23 8GD, UK
Sonardyne for method that 7823 High Power Transponder/ Tel: +44 (0)1224 707875
would allow their Focus ROTV Responder with a directional Fax: +44 (0)1224 707876
towfish to be positioned with an beam pattern (±15°) was
accuracy better than 1% of slant supplied, mounted in a special USA
range, without using a second frame on the Focus. Sonardyne Inc.
vessel, we took up the challenge.
11210 Steeplecrest Drive
The transponder was ‘cut down’ transponder to be used at lower Houston, Texas 77065, USA.
The solution proposed was to a size suitable for the towfish frequencies which are better Tel: +1 281 890 2120
based around Sonardyne’s suited to the transceiver and Fax: +1 281 890 7047
by eliminating the internal
proven Big Head USBL battery pack , with power instead required long ranges.
transceiver which is able to being drawn from the vehicle. Singapore
ignore ship-generated noise in During the survey, this Sonardyne Asia
combination of equipment Pte. Ltd.
favour of acoustic signals Changes were also made to the
Second Floor, 35 Loyang Crescent,
allowed slant ranges of over
coming from great distances. USBL software to allow the Singapore 509012.
3,000 metres to be achieved Tel: +65 542 1911
and the team’s accuracy
USBL reels them in requirements met. Analysis
Fax: +65 542 6937
has since showed that ranges of
The versatility of Sonardynne require USBL as an acoustic Brazil
over 5,000 metres could be Sonardyne Brazil Ltda.
USBL as a construction reference for station keeping
obtained under similar conditions. Alameda do AÇude,
survey positioning tool is now during maintenance operations
470-Novo Cavaleiros, Macaé,
recognised in the cable lay or plough tracking during cable RJ, Brazil 27930-310
With the use of versatile
market place. operations. Seven vessels that Tel: +55 (0)24 773 4155
transponders such as the 7823
Fax: +55 (0)24 773 3989
now have Sonardyne USBL are and Super Sub-Mini, supplied Email: email@example.com
The growing world-wide either owned or operated by for an earlier phase of the
demand for laying and Global Marine. Systems have Norway
project, an entirely new range Aqauadyne AS.
maintaining also been supplied of options is created for Solbråveien 41,
telecommunications to Havila, Tyco, survey companies wanting to N1370 Asker, Norway.
cables has in turn TeleDenmark and Tel: +47 66 90 03 30
work economically with
Fax: +47 66 90 01 41
fuelled demand recently Alcatel for towfish in deepwater by Email: firstname.lastname@example.org
for specialist their new build tracking them directly from
vessels. These CS Cable Installer cable layers the tow vessel.