Avionics News July 2015 - 58

THE STANDBY POWER DILEMMA

available to drive critical systems for 30 minutes in the event
both alternators are lost.
Similar constructs are available for retrofit under suppleproviding varying amounts of protection to the pilot in case of
mental type certificates by B&C and other suppliers, though
electrical problems. For the general aviation cockpit upgrading
some involve a second full-capacity alternator and its drive.
to glass from analog, multiple standby-power options exist.
Then there's the RAT, or ram air turbine - an option avail
available for retrofit to light GA aircraft under multiple STCs.
Integral standby power
Basic Aircraft Products makes two versions of these windAspen Avionics' top PFD and MFD
driven alternators, both of which
both contain a standby battery to keep
function similarly.
the screen and sensors working in the
The RAT system is mounted in
BY WORKING WITH THE
event of a loss of electrical power;
the wing with an activation control
AIRCRAFT OWNER ON A
the company also offers an additional
in the cockpit; activating the system
STAGGERED UPGRADE
standby battery. Most systems offered
drops the RAT down below the wing
PATH TO ALL DIGITAL, THE
for experimental aircraft include an
where high-pressure airflow spins
OWNER GETS TO TAKE ON
option to connect a standby battery -
the turbine attached to the alterna
alternaTHE
CHANGE
IN
BITES
AT
where, that is, the battery isn't already
tor. The BPE-14 delivers 6 amps
standard equipment.
ANNUAL INSPECTIONS
of 14-volt power at an airspeed of
Airliners and business-turbine
85 miles per hour; the larger, more- POSSIBLY AT HIGHER
aircraft generally employ a standby
powerful BPE-14/28 can deliver
TOTAL COSTS, BUT WITH
power system in addition to redundant
up to 12 amps of 28-volt power,
SMALLER INDIVIDUAL
generating sources.
or 18 amps of 14-volt power, at a
PAYMENTS. AND MANY
True Blue Power, a division of Midtrue
airspeed of 150 knots. Several
AVAILABLE OPTIONS
Continent Instrument Co. Inc., offers
popular GA aircraft are covered by
EXIST TO INCORPORATE
what was one of the first standby batBPE's STC, among them the Beech
STANDBY POWER EFFORT
teries employing new Nanophosphate
Bonanza, Cessna 182, 206 and 210,
DURING THE FINAL STEP
lithium-ion cell technology in place of
Mooney M20 (A-R), and Piper's
OF THE PANEL'S DIGITAL
older technologies such as sealed leadPA-28 and PA-32.
CONVERSION.
acid or nickel-cadmium alternatives.
By and large, all these options
Several other avionics-system
can be retrofitted in some manner,
manufacturers also offer their own
though like the factory standby
combinations of electrical-power redundancy for their glass
systems, usually at capacities far reduced from the main
cockpits. Thank the emergence of safer, smaller lithium-ion
system. Avionics shops might consider the following options
batteries as a viable source for standby power - and envifor aircraft owners and pilots.
ably light weights for the power they provide.
In many ways, an additional battery offers the lowest-cost,
Stand-alone standby batteries
simplest approach to enjoying standby power in a general
Depending on the main bus construction, adding an alteraviation aircraft lacking such redundancy.
native battery may be as simple as replacing the charging
regulator with one that can keep charged both the main-ship
Standby generating power
and standby batteries - and something to make the switch
Several vendors offer standby alternator systems, includwhen the need arises.
ing B&C Specialty Products of Newton, Kansas. B&C offers
A second battery may be the simplest option for meeta 20-amp standby alternator long used in Beechcraft and
ing regulatory and common-sense requirements for power
other aircraft.
redundancy, and the FAA provides guidance on how a secB&C's own solid-state voltage regulator handles the
ond or standby battery can qualify.
main-ship power-regulation chores and brings online the
Options include adding a second bus on the charging sysstandby alternator when the main ship system fails, alerting
tem and a switch to manually add the standby battery power
the pilot with an annunciator light in the panel. A secondary
along with a more-limited connection to aircraft devices
battery also is installed on the alternative bus, with power
with nothing more than the minimum needed: One PFD and
Continued from page 57

AVIONICS NEWS

JULY

2015

Table of Contents for the Digital Edition of Avionics News July 2015