What is a TSO?
An FAA Technical Standard Order (TSO) means the part is qualified to a Minimum Operational Performance Standard (MOPS) for specified materials, parts and appliances utilized on civil aircraft.
A TSO authorized part qualifies as an airworthy component.
What is TSO-C173?
This particular TSO is for manufacturers of permanently installed rechargeable lead acid aircraft batteries and nickel-cadmium aircraft batteries.
What type of aircraft batteries does TSO-C173 apply to?
TSO-C173 applies to permanently installed batteries providing power for aircraft equipment including emergency and standby systems and electrical power to start aircraft engines or auxiliary power units.
Can a TSO authorized battery be installed on any aircraft?
The TSO battery can be installed on an aircraft only after showing that the airworthiness requirements (certification basis) of a specific aircraft model are met by the TSO battery. A separate FAA approval may be required to install the battery on an aircraft.
What is the difference between TSO authorization and PMA approval?
TSO authorization means the battery is qualified as an airworthy component and can be installed in any aircraft by showing that the requirements (certification basis) of the specific aircraft model are met by the TSO battery.
PMA's are application specific, i.e. the approval applies only to the specific aircraft model number(s) for which the battery is approved.
What are the benefits of a TSO authorized battery?
Airframe manufacturers seeking Type Certification of an aircraft will save time and certification costs by selecting a TSO authorized battery that has already met FAA TSO-C173 standards and is qualified as an airworthy part.
STC applicants will also save time and certification costs when selecting a TSO authorized battery.
End users selecting a TSO authorized battery that meets the requirements of their airplane have the advantage of a qualified airworthy battery when altering their aircraft without the need of a PMA specifying their aircraft model number.
What does TSO authorization mean to the manufacturer of a TSO part?
TSO authorization is an FAA production approval to manufacture a specific part (battery) and sell it for installation in any qualifying aircraft.
What is a qualifying aircraft?
A qualifying aircraft is an aircraft having battery requirements that are met by the TSO authorized battery.
What does it mean when a battery is marked with TSO authorization?
When a battery is marked with TSO authorization that means it has met the Minimum Operational Performance Standard (MOPS) of the TSO specifications. TSO specifications are independent of the battery's intended installation on an aircraft.
What requirements has a TSO authorized battery met?
A TSO authorized battery has successfully met the requirements of TSO-C173 and RTCA/DO-293.
What are some of the requirements included in TSO-C173 & RTCA/DO-293? Electrical performance: Capacity and power ratings at various temperatures, charge and discharge characteristics, life cycle testing, charge acceptance, charge retention, recovery from deep discharge and shelf life.
Safety: Short circuit, induced destructive overcharge (thermal runaway), insulation resistance, dielectric strength, explosion containment, strength of component parts (handles and connectors).
Environmental characteristics: Operational and crash safety, shock, vibration, altitude, temperature shock, humidity, salt spray, fluid contamination and fungus resistance.
Refer to the User Declaration of Design Performance (DDP) for a specific battery to see a complete list of requirements and tests performed. DDP's can be found at: www.concordebattery.com on the "Literature, Manuals and Technical Information" page.
What kind of FAA approval is required to install the TSO battery? Original Equipment:
If the TSO authorized battery is Original Equipment, it can be installed.
The TSO authorized battery can be installed with a STC that specifies the TSO authorized battery.
Form 337 Field Approval: (The installer should consult with their local airworthiness authority to determine if/when a Form 337 is required).
If the TSO authorized battery is equal to the original certified design battery listed in the "Illustrated Parts Catalog" (IPC), the battery may be installed using FAA Form 337.
If the TSO authorized battery is equal to the original certified design battery installed with FAA approval, the battery may be installed using FAA Form 337.
Refer to AC 43.13-2B: Aircraft Alterations
Refer to AC 43-210: Procedures and Check List for Field Approvals
Which Instructions for Continued Airworthiness should the customer use?