Give Your Battery The Credit It Deserves

August 2021

An aircraft’s battery is one of the highest-maintenance components on board. Not many other items are due every three months or 100 hours. And for flight departments with heavy flight schedules, such as charter services or air ambulances, batteries could require the aircraft to be down nearly every month.

Yet this workhorse of a unit is continually ignored, left idle and unused for long periods, pushed hard with low levels, and occasionally allowed to deep discharge. Through it all, it is expected to function without fail.

And it is cursed when, during that one critical flight when the company’s president is on board, the battery will not crank, and the aircraft and passengers are stranded.

Although the first reaction may be to fault the battery, most premature battery failures can be attributed to one thing…human error. 

Buy The Correct Battery

Regularly, Duncan Aviation tech reps field phone calls from operators frustrated that their batteries have not provided the long life that was advertised when they purchased them.

A premature failure does not always indicate a defect or fault on the part of the battery but rather on the operator for not purchasing the correct type of battery required for their flying schedule.  

A well-maintained sealed lead acid battery can provide three to five years of dedicated service.  On the other hand, a NICAD, or nickel-cadmium battery can have a life span of 8-10 years on average but requires more periodic maintenance.

The best battery purchase for a charter company, air ambulance, or any operation that flies short, frequent one- and two-hour flights many times a day or week is a NICAD. Sealed lead acid batteries are also a great option, but they are not designed to function with this type of heavy use for a long time.

Extreme temperatures also impact the longevity and effectiveness of battery life. Suppose you fly primarily in extreme cold and hot climates, such as the northern territories of Canada or along the equator. In that case, NICAD is a hard-working battery and will provide the best performance.

Having the correct battery for your flight operation will not prevent premature failure. They still require regular maintenance and care.

Shut The Lights Off

If I could give you just one piece of advice, it is this. Most battery problems can be avoided if the last one out of the cockpit would simply shut off the lights.

The number one reason aircraft batteries fail at start-up is because they were allowed to deep discharge overnight when the master switch was left on.

An overnight deep discharge is especially devastating for lead acid batteries. When a small charge is left to pull from these batteries, even for just a few days, the cells are destroyed. There is no alternative but to replace them.

Make sure all the switches are off before putting the aircraft to bed. It takes only a few seconds to shut it down, but many pilots miss that step. 

If powering down the aircraft continues to be a problem, we suggest changing to a NICAD battery. NICAD batteries will still need to charge before the aircraft is able to take flight, but the deep discharge does not do any immediate harm. However, constant discharge and recharging on a battery will take its toll.

You may think an aircraft battery is a simple purchase. However, based on the number of batteries that come to Duncan Aviation for maintenance and repair, it is a purchase that should be taken more seriously. The battery shop at our Lincoln MRO facility alone sees up to 150 batteries each week.

Duncan Aviation Battery Team

The Lincoln facility more than doubled its battery service space to nearly 1,400-square-feet, adding a new battery cooler, twice as much bench space, and advanced test sets including 2400w programmable DC electronic load banks, lead-acid analyzers, and main NiCad charger analyzers.

We also added battery shops at both of Duncan Aviation’s Battle Creek and Provo MRO locations. All three locations have every test set, battery charger, and capacity gauge available to perform capacity checks, testing, and maintenance for every aircraft battery in service on today’s business aircraft, along with dedicated rooms for both lead-acid and NiCad battery services.

All of the main Duncan Aviation Satellite locations can offer a form of main ship and emergency power battery capabilities.

Batteries need to be given more credit in the successful operation of your aircraft. Think about it. They are the first component to engage an aircraft’s electrical system and the last line of defense before everything shuts down in an emergency.

You want them to work.

You need them to work.

Getting The Most Out Of Your Aircraft Battery:

• Make sure the master switch is in the off position before shutting down the aircraft and walking away.
• When on the ground, disconnect the aircraft batteries and use ground batteries.
• Use ground power assist at start-up.
• Perform periodic voltage and visual inspections. There should be no excessive voltage difference between cells, electrolyte build-up or bulging cells.
• Don’t ignore inspection requirements.

For more information about your aircraft’s batteries, contact Jerry Cable, Duncan Aviation Accessories Tech Rep at +1 402.479.8112 or via email at Jerry.Cable@DuncanAviation.com