DHC-6 Twin Otter STC SA03971AT Approved to Install Concorde Batteries

Concorde announces FAA approval of STC SA03971AT to replace nickel-cadmium main and auxiliary batteries on DHC-6-1, DHC-6-100, DHC-6-200, and DHC-6-300 vintage aircraft.


WEST COVINA, CA -- Concorde is pleased to have the RG-380E/60L selected as the Original Equipment battery for Viking Air Limited new production DHC-6-400 aircraft. Concorde is also pleased to announce FAA approval of STC SA03971AT to replace nickel-cadmium main and auxiliary batteries on DHC-6-1, DHC-6-100, DHC-6-200, and DHC-6-300 vintage aircraft.

The STC provides for the replacement of the heavy duty main 40Ah nickel-cadmium or AN-3150 lead-acid battery and/or the nickel-cadmium auxiliary battery.  The main battery can be replaced with either of Concorde’s popular RG-380E/44 (42Ah) or higher capacity RG-380E/60L (48Ah) battery for cold weather operations. If the aircraft has not been modified for removal of the auxiliary battery, the original nickel-cadmium auxiliary battery can be replaced with the new RG-300 (3.3Ah). 

RG-380E/44, RG-380E/60L and RG-300 are all TSO authorized and as such, have passed rigorous TSO-C173 testing for duty cycle, electrical performance, temperature extremes, shock/vibration and environmental requirements. Concorde’s valve regulated lead acid (VRLA) recombinant gas (RG®) absorbed glass mat (AGM) technology has been proven as reliable, durable and safe for over 30 years.  Superior performance can be attributed to unique design features such as proprietary PolyGuard® separators (an additional layer of protection against shorting, unique to Concorde) robust plate construction, over the cell wall intercell connections for reduced internal resistance and a commitment to quality standards.

The advantages of converting from nickel-cadmium to Concorde’s RG® Series batteries include lower cost of acquisition, zero maintenance and reduced battery costs per flight hour. Concorde batteries do not require deep cycling to remove the “memory effects” seen in nickel-cadmium batteries, do not require water or electrolyte replenishment and have no risk of thermal runaway.

With the benefit of RG® Series batteries shipping Hazmat Exempt, transportation is more cost effective regardless of whether shipping by land, sea or air.

Concorde designs and manufactures over 90 models of Original Equipment and direct replacement batteries for fixed wing and rotary aircraft and has a reputation for designing application specific solutions. Concorde batteries are installed as original Equipment by the majority of aircraft manufactures and adopted by military aircraft operators worldwide.

Manufacturing safe, durable and reliable Military and Commercial TSO, FAA-PMA and OEM certified aircraft batteries for over 30 years. 

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