The Duncan Download Blog: Business Aviation Advice & Observations

Duncan Aviation's New Hangar Open House is a Success!

Posted by Diane Heiserman on Thu, Jul 17, 2014 @ 11:20 AM

New Hangar Open House

Attendees listened to Chairman Emeritus Robert Duncan review the company's past, present projects and the future of Duncan Aviation. 

On Tuesday, July 15, Duncan Aviation welcomed more than 200 customers, industry partners and local dignitaries to an all-day open house event in their newest maintenance hangar and largest expansion project in Lincoln, Nebraska.
Customers attended informational sessions, toured the Lincoln facility and visited with industry vendors and OEMs. The fun continued into an evening reception with music, food, drinks.

Duncan Aviation's President Aaron Hilkemann and Chairman Emeritus Robert Duncan, welcomed everyone briefly explaning the company's efforts to construct a hangar that would help prevent physical waste, increase energy efficiency and improve productivity saving money for the company and Duncan Aviation customers.

Click to view a time-lapse video of the hangar construction. 

Thanks Again to Our Event Sponsors

















Two Most Common Failures of the APS-80 Autopilot System

Posted by Duncan Download Blog on Tue, Jul 15, 2014 @ 09:00 AM



Larry  Troyer, Duncan Aviation Avionics Instrument Tech Rep, troublshoots the two most common causes of APS-80 Autopilot System failure. 

The autopilot / flight director system is a complicated system that is common in aircraft from light twins to corporate jets. 

  1. FGC-80- (Flight Director)
  2. APC-80
  3. APA-80

The FGC-80- (Flight Director) processes all lateral/vertical signal inputs depending on the selected mode. It controls the position of the command bars in the Flight Directory Indicator and sends commands to the APC-80. APC-80 receives and processes commands from the Flight Director computer and passes them on to the APA-80, which drives the individual servo motors to control aircraft flight.

Two Most Common Failures

1.   Autopilot intermittently disengages during flight

Most likely cause is the APC or APA. These computers have multiple internal dc power supplies that tend to get out of tolerance or fail completely. They can be temperature sensitive (hot or cold) failing at one specific temperature.


  • If you are able to duplicate the discrepancy on the ground, it is possible to isolate the faulty computer by heating or cooling each box individually.
  • Engage the autopilot on the ground and manually override the controls in pitch or roll. If the autopilot disconnects, the most likely cause is in the APA due to faulty torque monitors.

2.   Autopilot will not engage


When the autopilot won't engage, the APA and APC is still most likely the cause. However because of the extensive internal computer monitoring, there are many other things that could be contributing to the failure. When activating the lever to engage the autopilot, the system automatically initiates a self-test routine. During this self-test a dc voltage is sent to the two NAC-80 accelerometers that in turn generate a fixed signal back to the APA. A correct signal is required to successfully pass the self-test. The NAC-80s also put out a valid flag which is monitored in the APP-80 control head as a condition for engagement.

Other conditions required before the autopilot will engage:

  • Valid vertical gyro
  • Valid from the yaw damper computer
  • Correct part number status on both computers (APA & APC)
  • Continuity thru the yoke disconnect switch

If you have access to a breakout box or logic monitor it helps to isolate the problem down to a box or aircraft problem. Other wise the majority of the times engage problems are caused by either the APC-80 or the APA-80 computers.

More Autopilot Squawk Solutions on the Duncan Download

Troubleshooting Business Aircraft Autopilot: Altitude Hold INOP

Troubleshooting Autopilot-Induced Control Surface Oscillations

3 Things to Look for in a Business Aircraft Autopilot Support Team

Diode Short Can Disengage Learjet 35A Autopilot


Tags: Avionics & Instruments, Squawk Solution, Troubleshooting

Aviation Nondestructive Testing

Posted by Duncan Download Blog on Thu, Jul 10, 2014 @ 11:09 AM


Fluorescent magnetic particle inspection on a generator dampener plate.

Nondestructive testing, or NDT, is a method of testing for defects in materials without destruction of the materials.

There is some form of NDT testing on nearly every aircraft inspection. It is often required to test aircraft parts, assemblies and other materials to determine if useful life remains or if cracks or corrosion hide below the surfaces.

Eddy current, dye penetrant, ultrasonic and magnetic particle inspections are all NDT methods used for required NDT testing. For major structural inspections on several aircraft models, NDT x-rays are required.

Duncan Aviation has one of the highest skilled in-house non-destructive testing teams in the industry. All technicians are trained and certified for basic Falcon NDT and several certified for advanced Falcon NDT testing. 

It is what they do full-time every day, day in and day out. They do not divide their time with other areas and work NDT part-time. 

The team currently has 8 certified NDT technicians, but to meet increasing demands, both internal and external, more certified NDT technicians are being added. 

Capabilities in Lincoln, Nebraska, are being expanded to include Bombardier Global and Embraer aircraft. And an NDT lab will open soon in Provo Utah. 

Duncan Aviation believes that being prepared to meet the smallest needs of every customer has the biggest impact and has invested millions of dollars in tools, equipment and talent to quickly and efficiently provide for required aviation maintenance services.

Keep reading about Duncan Aviation’s  NDT capabilities  and what sets us apart from other MRO service providers.

Tags: Airframe Maintenance

Don't Forget The Pre-Buy 6

Posted by Duncan Download Blog on Wed, Jul 02, 2014 @ 02:42 PM

When buying or selling an aircraft, nothing can be more stressful than the "moment of truth"–that point in the transaction where the buyer and seller are presented with the aircraft squawk list and it is time for them to negotiate and finalize. Partnering with a service provider who knows how to clearly present its findings and communicate well with all parties involved can allow the key players to breathe a bit easier.

"Pre-purchase evaluations are complex, there’s no way around it," says Tim Klenke, an airframe service sales representative with Duncan Aviation. "Stress can be tempered somewhat, though, when the pre-buy evaluation occurs at a facility with a good reputation, excellent communication and integrity."

Pre-purchase events and aircraft purchases are uncharted territory for many operators. There are a lot of people involved, lots of choices to make and usually some surprises along the way.  

Here are Tim's suggestions on what to look for when selecting a service provider for a pre-buy evaluation.

Top 6 Things When Selecting a Pre-Buy Provider

  1. Reputation. How is the facility viewed within the industry?
  2. Experience. How many pre-buys does a facility perform? Do the buyer and seller feel comfortable with the provider and have confidence in the provider’s ability to understand and execute the pre-buy according to the terms and conditions of the buyer/seller agreement?
  3. Post pre-buy capabilities. Can the facility perform interior work, exterior paint, avionics upgrades and larger inspections?
  4. Import/export proficiency. Does the facility have these services if the airplane is coming from or going overseas?
  5. Communication. This skill is critical in pre-buys; everything must be crystal clear and understandable for all parties – buyers, sellers, brokers, lawyers and the service facility.
  6. Technical support. Does the facility offer in-house Technical Representatives for each model airplane who can engage quickly with OEMs and teams to resolve unexpected issues without disruption in schedule?

Pre-Buy Services For Buyers & Sellers

Duncan Aviation's only focus during a pre-buy evaluation is to provide the most accurate assessment on the condition of an aircraft to the buyer and seller. Our comprehensive services allow us to correct most discrepancy repairs in-house.

For more information about Duncan Aviation Pre-Buy Services, give Tim a call. 

Tags: Airframe Maintenance, Aircraft Sales

Want to Earn 5X AVTRIP Points? Stop at Duncan Aviation!

Posted by Duncan Download Blog on Fri, Jun 27, 2014 @ 08:00 AM


open-house2Fly in on Tuesday, July 15, and celebrate the opening of Duncan Aviation’s newest maintenance hangar facility with special events, including:

  • Informational sessions
  • Vendor displays
  • Evening reception with music, food, drinks and great conversation

View the full agenda at

Fly in any time during July 14-18 and receive FIVE TIMES the AVTRIP* points on contract, retail or maintenance purchases.  Make certain to tour our brand new maintenance facility during your fuel stop.

In June of 2014, Duncan Aviation completed the largest expansion project its Lincoln, Nebraska, campus has ever seen. The 175,000-square-foot facility will be comprised of two 40,000-square-foot maintenance hangars and a 95,000-square-foot office and shop space.

The expansion comes in response to customer requests and changing customer needs. As the industry continues to shift toward larger business aircraft, a trend fueled by technological advances and increased globalization, Duncan Aviation’s previous hangars were unable to accommodate the volume of maintenance, modifications and completions work our customers require.

*How Do AVTRIP Rewards Work? 

  • Earn two (2) points per gallon or 1 point for every 2 liters each time you refuel at an FBO offering the AVTRIP rewards program.
  • Points are awarded on retail and contract fuel purchases at participating Avfuel branded locations.
  • Earn 1 point for every dollar on any international service arranged with Avplan Trip Support.
  •  AVTRIP offers frequent promotions for bonus points and has many non-fuel earning opportunities - so points accumulate fast.

 Find out more or sign up for AVTRIP at


Tags: Announcements, Duncan Aviation - Lincoln


Posted by Duncan Download Blog on Wed, Jun 25, 2014 @ 10:29 AM

Aircraft paint can beautifully reflect hours of painstaking care and preparation—or it can cover a multitude of sins. The trouble is, you can’t always tell which applies to your aircraft until long after the job is finished.


According to George Bajo, completions sales representative for Duncan Aviation, “Anyone can shoot a glossy coat of paint. But the value is in the details.”  

He goes on to suggest operators conduct a visual inspection for dirt specs in the paint finish as one identifier of a quality job. “While a few dirt specs should be expected, a large number is cause for concern.”

The attention to detail at the sealed windows and cleanliness of the painted landing gear are also evidence of a job done right. New stair treads, dressed boots, wiped down wheels and wheel wells, painting inside of gear doors, radome boots that don’t yellow and erosion tape are also extras that customers should expect.

“It’s all about the details,” George says. “That’s what you pay for.”

Duncan Aviation Field Guides

To help aircraft owners identify a quality paint job and decide when to take an aircraft in for a touchup or full repaint, Duncan Aviation industry experts answer questions about pressing paint maintenance issues in the recently updated “More Than Skin Deep: Paint Maintenance and Turbine Aircraft Value” field guide.

This field guide explores routine maintenance and turbine aircraft market value, paint processes, and criteria to consider when selecting an aircraft paint service provider.

Paint Maintenance Topics
  • Paint Maintenance Topics
  • How to Recognize A Quality Aircraft Paint Finish
  • How Long Does Aircraft Paint Last?
  • Routine Maintenance & Paint Integrity
  • Aircraft Paint Services

Duncan Aviation's field guides address topics of importance to business aircraft operators around the globe and are written by our very own technical experts.

These documents are available as free PDF downloads. 



Tags: Aircraft Sales, Paint Refurbishment

4 Tips on Military Transition to Civilian Employment

Posted by Diane Heiserman on Wed, Jun 18, 2014 @ 03:24 PM

Military Departure Advice

Getting out of the military soon? If you are interested in beginning or continuing your aviation career with Duncan Aviation, we offer a few tips on transitioning from military service to civilian employment. This advice comes directly from Duncan Aviation employees.

Plan early

Don’t wait until four weeks before your departure date to begin preparing your resume. As soon as you make the decision to leave the military, begin planning your transition. Resume Writing Tips.

Use all available resources

Today’s technology allows almost anyone to search and apply for employment nearly everywhere in the world. Take advantage of the internet; utilize all resources your branch of the military has to offer and network with military friends and other connections. Military Transition Assistance FAQ.

Narrow the scope of your job search

Knowing what you want to do or where you want to live can help you focus your efforts & conduct a more controlled & effective search. Do you want to stay in a particular geographic area or focus on a targeted occupation?

Use proper terminology

When creating a resume and filling out applications, do not assume that the corporate recruiter will understand military terminology. Be clear on how your military training can translate into the job for which you are interviewing.

Putting Your Military Skills to Good Use

For many years at Duncan Aviation, some of our best employees and mechanics have been trained by and served for our country. As a matter of fact, more than 25% of our employees serve or have served in the armed services. Almost every branch of the military is represented at Duncan Aviation in departments and shops such as airframe maintenance, avionics install, turbine engine services and engineering, to name a few.

Although entering civilian employment will be a major life adjustment, there are many things at Duncan Aviation that will remain the same: attention to the details of your work, focus on getting the job done right and the support from fellow employees. We are proud of our employees and the quality workmanship they put into the products and services we offer.

We strongly encourage military personnel to apply for career opportunities.

Duncan Aviation is an equal opportunity workplace and an affirmative action employer.

Tags: Careers & Recruiting, Videos

What Business Aircraft is the Right Business Aircraft For you?..

Posted by Duncan Download Blog on Tue, Jun 10, 2014 @ 05:08 PM

Market-Update_blogOne of the hardest decisions to make when purchasing a business aircraft is to purchase the make and model that is right for you and your business needs. The last thing you need is to take off on your first business flight and discover your aircraft does not fully meet your requirements.

A full schedule with multiple passengers for long hours requires an aircraft with appropriate cabin capacity and fuel range. Anything less will result in frequent refueling stops and a lot time sitting on the tarmac.

However, buying a long-range jet for short infrequent flights will result in higher than necessary operating costs.

Identifying the right aircraft for you is can be a complicated process. With more than 80 make model business aircraft to choose from, how do you narrow the field to make the right decision?  

You Need A Tool

  • A tool that breaks down all the available business aircraft by category, available features and many other details
  • A tool that helps to prioritize your business needs and desires, narrowing the pool of appropriate aircraft
  • A tool that would simplify the investigation of the market place, identifying several available options that meet your needs

 Yeah...Here Is That Tool

And if you still have questions...these are the guys that can help you!


Duncan Aviation Aircraft Sales Representatives

Tags: Aircraft Sales

Duncan Aviaton: Breaking Ground Across Six Decades

Posted by Diane Heiserman on Fri, Jun 06, 2014 @ 01:15 PM

Duncan Aviation was established in 1956 by business aviation pioneer Donald Duncan. It began as a Beechcraft Dealership in Omaha, Nebraska. Then in 1963 the operation moved to Lincoln, where it put down deep roots and experienced aggressive growth that has spanned across six decades.

Today Duncan Aviation is the largest family-owned premier resource for business aircraft maintenance service in the world. 

Let's take a look back and see the ground-breaking expansion of Duncan Aviation in Lincoln, Nebraska.

1960s & 70s

Duncan Aviation circa 1963 1977DArial_blog-1Duncan Aviation put down roots at the newly established Lincoln, Nebraska, Municipal Airport (LNK) in 1963. During the 1970s, they continued to expand and grow along the east side of the airport with a new maintenance hangar. 

Read more about Duncan Aviation's history and how is was established in the 50th Anniversary Duncan Debrief

Duncan Aviation circa 2000




In 2000, Duncan Aviation opened two new large hangars to accomodate the largest aricraft of the time, including the Bombardier Challenger and Gulfstream. The construction project also included much needed shop and storage space.  



In the fall of 2011, Duncan Aviation broke ground again. This time on a 45,000-square-foot paint facility on the south end of the ramp. It will accommadate the largest business aircraft in use today, including Bombardier's Global Express and Dassault's Falcon 7X. It was official opened in the Spring of 2012. You can read more about this state-of-the-art paint facility in the Fall 2012 Duncan Debrief

Watch custom paint time-lapse video.


The latest ground-breaking for Duncan Aviaton came in the Fall of 2012 on a 175,000-square-foot facility that is comprised of two 40,000-square-foot maintenance hangars and a 95,000-square-foot office and shop space.

In July of this year, Duncan Aviation will host an Open House to members of the business aviation community to celebrate the opening of it's latest and largest construction project in Lincoln, Nebraska. 

Watch time-lapse construction video

We are proud and invite you to come and celebrate with us. Go here, for more information and to register to attend.  


Tags: Announcements, Duncan Aviation - Lincoln

Duncan Aviation's New Hangar Goes Green

Posted by Duncan Download Blog on Wed, Jun 04, 2014 @ 12:29 PM

Duncan Aviation new business aircraft maintenance hangarThis summer, Duncan Aviation will complete the largest expansion project its Lincoln, Nebraska, campus has ever seen. The 175,000-square-foot facility will be comprised of two 40,000-square-foot maintenance hangars and a 95,000-square-foot office and shop space.

As the industry continued to trend toward larger business aircraft, Duncan Aviation recognized their current hangars would soon be unable to accommodate the volume of maintenance, modifications and completions work their customers requested and required. This industry shift is fueled by technological advances and increased globalization

Chief Operating Officer, Jeff Lake said the company decided to build now because the size and number of aircraft they are working on and will continue to work on simply did not fit well in the current hangar space.  

“We anticipated this trend, which is why we invested in the new 45,000-square-foot aircraft paint facility two years ago. Now it was time to support the maintenance side,” Lake said.

Duncan Aviation already boasts a row of hangars that dot the runway at Lincoln’s Municipal airport. Now as the expansion is nearing completion, they will add two more.

To view the progress through photos and a time lapse video, visit

To get information and register to attend the Open House Celebration, go here.  

Going Green

When Duncan Aviation’s Senior Team decided it was time to invest in a new, larger hangar facility, they wanted to ensure it was of the highest quality, just like the aircraft services provided inside. That priority also aligned well with the company’s desire to make “green” decisions whenever possible.

“Things that are good for the environment are good for our employees, and that translates into an excellent experience for customers as well,” Lake said.

Kyle Link, Tectonic Management Group, Inc.’s designer/builder senior project manager for the expansion said the materials and design elements chosen are a new concept in hangar environment. From the LED lighting that senses daylight and automatically dims itself to the radiant floor heating, it’s top of the line.

“You can’t cost effectively dim fluorescent lights. You would have to shut off individual bulbs. But LED lights can be dimmed gradually, saving energy and making it less apparent to team members,” Link said. That combined with the skylights and windows, makes the hangar brighter with all the lights off than any of the other hangars with every bulb lit.

During construction, Duncan Aviation made deliberate decisions to go above and beyond the energy code and choose more cost and energy-saving options such as skylights, sidewall daylight panels and radiant floor heat.

“It was really an easy decision to invest a bit more up front and do what’s right for our environment, especially if it means we’ll save money in the long run,” Lake said. “With as quickly as technology changes, we need to be a bit ahead of the game.”

Read more about Duncan Aviation’s Green Hangar in the Spring 2014 Duncan Debrief.

Tags: Airframe Maintenance, Announcements


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