Model 3328 Special

Patent Pending

GPU Starting Unit Model 3328 Special
  • GPU Starting Unit Model 3328 Special
  • GPU Starting Unit Model 3328 Special
  • GPU Starting Unit Model 3328 Special

These StartPac are designed for ground use to perform repeated engine starting functions. When connected to AC power, the depleted batteries can be charged in four hours with the built-in battery chargers.

This turbine starting unit is designed to provide superior starting for large turbine engines including the TPE 331.

Batteries have no memory effect and can be recharged at any time. Made in the USA.

Start Pac also offers a wide selection of ground power units and starting units for portable power and portable power supplies, such as the classic yellow aircraft starter unit. Browse our website to discover our extensive product line or visit our tutorial section to learn more about our power supply products. Have a question or need assistance with your order? Start Pac provides customer service support via phone and email, making it easy to find the yellow GPU or railroad locomotive starter unit you’re looking for.

The Model 3328 Special is a powerful 28V unit designed for repeated engine starting requirements.


  • 78 Amp Hours at 10 hour rate
  • 28.5 Volt DC-30.5 Volts at rest
  • Sealed cells non-hazardous
  • Valve regulated high amperage output lead acid
  • 2800 Peak amps
    Power supply/charger

  • 6 built in chargers for faster recharge time
  • Battery recharge time from depletion is approximately 3-4 hours
  • AC Input- 110 Volt or 220 Volts

  • 250 Amps maximum continuous DC load

Load vs. Time (click to view larger)
3328 Special Load vs Time Curve

Voltage Drop vs. Load (click to view larger)
3328 Special Voltage Drop vs Load Curve

The following dimensions apply to each of the 3300s:
38″x21″x20″ Handle Height 48″.

All Start Pac™ products come with a 1-year warranty on workmanship and materials. Batteries are cycle-dependent and therefore are not covered under this warranty.

Please handle this unit in a responsible manner. Start Pac™ is not responsible for damages caused by misuse or neglect.

This GPU is rated at 2800 peak starting amps and is a full 28 volt battery pack (28.5 volt, to be exact). Due to the extra starting power provided by the 28.5 Volt batteries, turbine engines will experience faster, cooler starts and extended turbine life. This model is primarily designed for superior starts on large turbine engines and the Garrett TPE 331.

This airplane starting unit can be configured for 110 Volt or 220 Volt AC input. This unit weighs 225 lbs./102 kilos.

Always recharge the GPU until the green light appears and leave it plugged in when not in use. If a heater is installed, turn unit off but leave plugged in.

Avoid discharging the batteries completely as damage to the cells can result leading to reduced capacity and premature battery failure.

Always recharge batteries soon after use.

There are approximately thirty 110 volt and thirty 220 volt NEMA plugs in use. Also, customers have various receptacle at their hangars and MRO facilities and may require specific AC cord length to meet their requirements. Due to these facts, we do not automatically provide AC power cords. If you provide the NEMA plug number and specify the AC power cord length you require we will build a cord to be shipped with your unit for a small fee.


For technical assistance, contact Jim Wurth, Chief Engineer/Product Designer/Pilot, directly at (928) 231-4536, toll free at (844) 901-9987 or via email at