Air-integrated (AI) computers
offer a menu of features, such as
calculating remaining air and bottom
time by monitoring air consumption.
They can even modify
the decompression schedule
according to the workload. For
example, if the computer detects
that a diver is breathing heavily at
depth, the model considers that
the diver is actually taking on additional
nitrogen, and may call for
shortened no-decompression limits
or extra decompression time.
AI models currently account
for more than a quarter of new
high-end computer sales in the
U.S., according to industry
experts. Jim Clymer of Suunto says
their Cobra is their best-selling
computer. Joe Stella, VP of
Scubapro/Uwatec, reports that
the top four or five selling computers
either are air-integrated or
watch style (some of which, like
Uwatec’s Aladin Air 2, can also
read tank pressure through electrical
transmissions from the tank
valve to the computer).
But they’re not perfect. Our recent poll of Undercurrent subscribers
unearthed a number of
aggravating incidents involving
screwy readouts, battery malfunctions,
and loss of tank pressure
transmission. (Note: some of these
reports involve older models, no
longer being distributed. Many are
also no longer being serviced).
When Good Displays Go Bad
If a computer’s display disappears
or becomes erratic, the causes
can be tough to diagnose. Joe
DiDia (Novi, MI) has had three
Oceanic Data Plus II units fail “with very little dive time on
them.” Oceanic replaced each unit
in a timely manner. During a trip
to Cozumel, one unit failed during
the first dive – the display would
only flash “On – Off.” On the second day, the second computer
failed the same way and two years
later, in Grand Cayman, his
replacement failed as the others
had. Though his warranty had
expired, “they replaced the third
unit without issue.”
“It’s my experience that more divers lose a dive due
to integrated failure than any other reason.” |
Alan Sankowski and his wife
(Hoffman Estates, IL) took a pair of
Suunto Cobra AIs on the Komodo
Dancer and experienced one nonrecurring
depth-reading problem
with each computer. They dive
almost identical profiles and check
each other’s computers throughout
each dive. “On our fourth dive,” recalls Sankowski, “I was surprised
to see my wife 10 feet below our
agreed max depth. After we had
both ascended a few feet, my computer
was reading eight feet deeper
than hers.” The crew lent the Sankowskis another computer and
during the dive the difference grew
until her computer showed eight
feet deeper. The computer that registered
deeper also showed more
nitrogen loading. “It appeared that
while the depth readings were inaccurate,
all of the algorithms seemed
to be functioning correctly,”
Sankowski reports. On more than
30 subsequent dives, both computers
behaved correctly.
The Sankowskis’ dive shop
returned the Cobras to Suunto.
No problems were found, and the
computers were returned. Says
Sankowski, “A large part of confidence
in one’s equipment is mental.
Since we did not experience any
problems in the last 30-plus dives,
I’ve become less concerned with the
reliability of the computers, and
more inclined to believe that the
problem was a one-time issue.”
The wrist strap on Bruce
Eanet’s (Washington, DC) Oceanic
Data Max Pro Air/Nitrox hoseless
computer broke when he was getting
back in the dive boat Akumal.
He didn’t lose his computer and got
a replacement strap from Oceanic.
But, Eanet says, that for a computer
that costs nearly $1,000, “There
should be no issue with the band
breaking after only three years.”
Hoseless Interruptus
Hoseless AI models rely on a
small battery-operated transmitter
on the first stage high-pressure
port to send pressure readings to
the console or wrist-mounted computer.
Suunto’s Jim Clymer says
that hoseless models are making
“steady increases” in share of the
AI market. And why not? One less
hose to worry about, and one less
gauge to fumble with. It’s a great
concept … when it works.
Dale Treadway’s (Omaha, NE)
Uwatec Air Z 02 wrist model
worked fine for two years, until it
stopped receiving the signal from its transmitter. He switched to his
“old backup Suunto EON” AI,
using his Uwatec as a backup. It
worked intermittently, but would
go for three or four minutes without
receiving a signal. He learned
from Uwatec that the electronics
of his Sea & Sea YS 90 Auto Strobe
interfered with the signal to his
computer. “Seems reasonable,” he
says, since he never had a problem
until he began using the strobe.
“The electronics of his Sea & Sea YS 90 Auto
Strobe interfered with the signal to his computer.” |
A strobe was also fingered as
the culprit when Greg Cruz
(Saratoga, CA) reported problems
getting his Oceanic Data Trans Plus
to consistently connect to the transmitter.
“Half the time I would get it
to connect and many times during
the dive it would lose the connection.”
It worked fine back at his dive
shop, so they determined his problem
might have been due to using
a strobe. On a subsequent trip the
computer twice worked at the surface
then failed at depth. Oceanic
sent him a refurbished unit, which
again lost transmission at depth. He
is now on his third unit, which has
managed to stay on during a couple
of dives, “Although,” says Cruz,
“it reads the water temp at a comfortable
99 degrees.”
Scubapro’s Joe Stella told
Undercurrent that electrical interference
can be eliminated by moving
the computer away from the electrical
source. For instance, a retractor
can keep a console model away
from a strobe or electric scooter. If
you dive with a wrist mounted AI,
try holding your strobe in your
other hand. Uwatec claims that its
“unique transmission technology”
ensures that if a signal is interrupted
by camera or strobe flashes, the
signal is reinstated in five seconds. Besides electrical interference,
there seem to be lots of other ways
data transmission can be interrupted.
Gary Nagel (Greenfield, WI) has
replaced his Oceanic Data Trans
Plus twice. The first time he used
his hoseless Oceanic, in Cozumel,
Nagel lost tank pressure transmission.
He replaced the batteries –
they cost twice the US price,
another good argument for always bringing spares – but they didn’t
solve the problem. Leisure Pro
replaced it without argument.
After a second failure and replacement,
Nagel said, “Although I
always got tank pressure readings
at home when testing the computer,
it never acted right when I went
diving. I decided to crank the
transmitter just a little tighter into
the first stage. Bingo, end of problem.”
Nagel points out that
Oceanic’s owner’s manual neglects
to mention how tight the transmitter
needs to be. “They should
include a ‘trouble shooting’ section
in their manual. It would stop
a lot of exchanges.” He used a
wrench for a reliably tight fit.
Mark Berger (San Diego, CA)
has gone through three transmitters
for his wrist-mounted Oceanic
DataTrans Plus. “They were
replaced without a problem during
warranty,” he notes, but the last one
cost him $75. “You never know
when they are going to go south.
But you can usually tell at the beginning
of a dive if you are going to
have a problem. (It will not link with
the receiver).” Berger says when his
tank pressure hits 300 psi, his Data
Trans Plus shuts down the time display
for the dive and flashes “GAS
ALERT” along with depth and amount of remaining air. This usually
makes it impossible to time his
safety stop. Berger points out that
the unit’s time display only has two
digits. “On occasion I like to do a
shallow dive that will last more than
99 minutes,” he notes, “and that is as
far as the computer can record.”
Otherwise, he finds the computer
easy to read with lots of information.
Anticipating a trip to the Turks
& Caicos, Kim DeWitt and her husband
(Evansville, IN) bought new
Oceanic AIs. They found that at
times, the signal was lost, “and it
required that the unit be held near
the main transmitter for a minimum
of four seconds to reestablish
communications.” This required a
“contortion with full gear and getting
your hand up over your head
backwards and holding it steady for
four seconds.” The DeWitts also
found that after the computers
went into sleep mode between
dives it was sometimes necessary to
get them wet before they reactivated.
They’re now using Suunto
Cobra console models.
Donald Wilson’s wrist mounted
Suunto Vytec occasionally locks
out after the pressure drops to zero
when changing tanks. The display
reads “fail,” and he is unable to
reset the computer for several
hours. It still shows depth, temperature
and time, but does not show
tank pressure, nor does it record
and save dynamic dive details. “The
owner’s manual, like all owner’s
manuals, a semi-disaster, does not
show the way out of this dilemma,
nor has anyone at Aqualung
[Suunto’s U.S. distributor] been
able to help me,” says Wilson.
Such experiences have soured
some dive professionals like Randy
Jordan, proprietor of Jupiter Dive
Center in Florida. Jordan makes
more than 600 dives a year, and is
familiar with all kinds of equipment.
“I often see people with integrated
units miss dives because
their unit went out. This means they lost their computer and their
submersible pressure gauge.” In
fact, he adds, “it’s my experience
that more divers lose a dive due to
integrated failure than any other
reason.” He has spotted many
hoseless integrated users turning
their tanks on and off a couple of
times before the transmitter makes
contact. Although divers say they
like the compactness of a hoseless
integrated computer, Jordan points
out that they often have to carry a
backup pressure gauge, in case the
unit fails. He says, “I carry several
lines that have integrated units and
I have chosen not to sell them.”
Dive industry marketers, of
course, defend the reliability of
their hoseless models. Uwatec’s
Stella says, “We get little negative
feedback on our hoseless category,”
and adds that his company, one of the first to offer hoseless computers,
will be bringing out a three-mix
model for technical diving that will
use different transmitters for each
of three different gases.
Suunto, says Jim Clymer, uses a
proprietary analog signal (similar
to a heart rate monitor), which is
less complex than competitors’
digital technology. Clymer says this
signal will be restored quickly if it’s
interrupted.
Suunto, by the way, is the leading
U.S. seller of dive computers
according to Leisure Trends, which
studies retail sell-through at participating
independent dive shops. For
the 12 months ending last June,
Suunto accounted for 46% of all
units sold. Oceanic was second with
a 25% market share, and Uwatec
came in third at 12%.