The Duncan Download Blog: Business Aviation Advice & Observations

Falcon: Special Commercial Program for F900EX S-Duct

Posted by Diane Heiserman on Fri, Jun 21, 2013 @ 12:12 PM

Contributed by Kevin Bornhorst, Airframe Tech Rep.

Pulled Spot Welds in S Duct

Multiple pulled Spot Welds in inner skin of the Falcon 900EX S-Duct.


Dassault issued Falcon Service Advisory FSA900EX-54-10-02-R5 in 2009 after receiving reports from F900EX operators about a brown discoloration and in some cases a distortion of sections of the S-duct inner skin.

The suspected cause of the discoloration is the overheating of the S-duct due to sustained use of the anti-ice power in cruise above 30,000 feet. Dassault has issued the AFM Temporary Change No. 61 that modifies procedures regarding the use of the override mode for engine #2 and wing anti-ice. They also added a check of the rivet condition inside the S-duct to the basic inspection

The distortion of the inner skins of the S-duct was determined to be an overpressure due to an excessively open HP valve, combined with a high N1 setting. Dassault has modified the design of Section #1 of the S-Duct to correct the distortion. Since the introduction of this redesign, the number of distortion reports has significantly reduced. 

Special Commercial Program

I want to remind Falcon 900EX operators that Dassault Falcon has a Special Commercial Program for the Falcon Service Advisory FSA900EX-54-10-02-R5 that extends the warranty on materials and provides a discount program for parts if exchanged prior to failure.


This program is for F900EX S-duct Sections 1, 2 and 3 that are made of 2024 aluminum alloy and is limited only to the correction of the discoloration and distortion issues discussed above.


  • Material warranty is extended from five to 10 years.
  • Labor warranty is extended from six months to 3 years.
  • No repair will be done on a part under warranty. Any section with cracks will be systematically exchanged with a new part.


  • If your F900EX is six year old or less, you will get a 50% discount off the regular new part price.
  • If your F900EX is 12 years old or less, you will get a 25% discount off the regular new part price.

If you have any questions about this FSA, don’t hesitate to ask me or any of the other Duncan Aviation Falcon Tech Reps.

Kevin Bornhorst is an Airframe Tech Rep located at Duncan Aviation's Battle Creek, MI, facility. He specializes in the Falcon airframe. His aviation career began in 1982.

Tags: Airframe Maintenance, Falcon

Falcon Aircraft Fuel Tank Management

Posted by Diane Heiserman on Wed, Apr 03, 2013 @ 08:00 AM

Contributed by Ron Grose, Airframe Tech Rep

There are two facts operators should be aware of when it comes to fuel:

contaminated fuel filter

Example of a contaminated fuel filter due to microbial growth.

  1. All hydrocarbon fuels have micro-organisms that live and grow in them and these bugs release sulphur-based by-products into the fuel.
  2. All hydrocarbon fuels have water in them which, when combined with the sulphur-based by-products, release sulphuric acid into the fuel.

To help eliminate the damage which can be inflicted into the fuel tanks by these bugs, operators need to perform a couple simple processes. 1) Sump the fuel tanks on a regular basis, weekly if necessary, to remove the water and debris left from the bugs and; 2) Perform the “Fuel Contamination Detection Test” (MP 28-00-00-280-801) at every “A” inspection or more often if needed, such as in a tropical environment.

If the “Fuel Contamination Detection Test” detects a high concentration of microbiological contamination, or if the operator suspects receiving a contaminated load of fuel, Dassault recommends treatment of the fuel with Biobor JF or Kathon FP 1.5 as directed by MP 28-00-00-910-803: “Treatment of Fuel System Contamination.” Dassault has revised this procedure by eliminating the “preventative treatment” option of these biocides. They only recommend the full “lethal dosage” treatment as directed by the MP.

Note: Fuel anti-icing products, such as Prist, are known to slow the development of micro-organisms but do not eliminate these bugs. This is the reason to use Biobor or Kathon only.

During the accomplishment of the “C” inspection, we recommend the removal of all of the fuel tank sump drain valves to inspect for corrosion of the valves/mating surface along with replacement of the seals in these drain valves. Since the fuel quantity probes are removed during this inspection, to perform the borescope inspection of the fuel tanks, this is a good time to inspect the probes and wire connections to them to ensure the connections are clean and installed properly to prevent future fuel quantity indication issues. Even though Dassault does not have a requirement to perform a calibration check of the fuel quantity system, Duncan Aviation recommends performing a capacitance, insulation, and calibration check at this inspection to ensure the quantity indication system is properly calibrated.

These recommendations will help operators maintain the fuel tanks correctly to eliminate costly repairs along with fuel quantity issues in the future.

Duncan Aviation is a Dassault Authorized Airframe Service Center offering complete airframe maintenance services, specializing in major and minor airframe inspections as well as heavy structural repair and modifications.

Ron Grose is an airframe tech rep at Duncan Aviation's Lincoln, NE, facility, specializing in the Dassault Falcon airframe. Ron is often sought after to speak about technical issues common to business aircraft and has particpated in several OEM advisory boards.

Tags: Airframe Maintenance, Falcon

Avoid Escalating Aircraft Maintenance Fees with Firm Fixed Pricing

Posted by Diane Heiserman on Tue, May 08, 2012 @ 06:00 AM

Contributed by Dale Hawkins, airframe service sales rep.

Business Aircraft Maintenance

Business aircraft budgets are tight. Firm Fixed Pricing gives more control over maintenance expenses.

When it comes to business aircraft maintenance costs, most operators are able to effectively budget what they want to spend on interior, paint, and avionics. But when it comes to airframe maintenance, there are many unknowns. Even a well-educated guess can still result in the Director of Maintenance (DOM) having to explain why the aircraft maintenance costs came in higher than expected. Firm Fixed Pricing offers business aviation customers a guaranteed labor price for scheduled inspection packages, giving more control over maintenance expenses.

How does Firm-Fix Pricing work?  

An MRO offering Firm Fixed Pricing agrees to perform scheduled inspections and all discrepancies noted as a result of these inspections at a predetermined fixed price. The price includes the inspection labor (often called flat rate), miscellaneous parts needed for the inspection, labor for discrepancies noted as a result of the inspection (unknowns) and all consumables. Due to continuous price fluctuations, major parts or outside vendor services are not included in Firm Fixed Pricing.

With all the unknowns, how is an MRO able to offer Firm Fixed Pricing?

Knowledge and experience is the only way a qualified MRO is able to offer Firm Fixed Pricing. Through years of performing the same airframe inspections over and over, innovations are discovered, efficiencies are gained and valuable historical data is collected; reducing the risk of a guaranteed labor rate.

Why aren’t more MROs offering Firm Fixed Pricing?

Simply put, the potential risk of losing profit margins is just too high. The majority of the reluctance stems from the unknown possibility of discovering major corrosion damage during an airframe inspection. A discovery of this type is not uncommon and can escalate the cost and extend the downtime of any airframe inspection.

Minor airframe corrosion is covered under the Firm Fixed Pricing program and corrosion that requires Engineering Services from the OEM are offered at an exceptionally discounted rate.

Firm Fixed Pricing for Falcon Airframe

Duncan Aviation has been offering Firm Fixed Pricing on Falcon airframes for six years. Since then many Duncan Aviation customers have taken advantage of the guaranteed labor rate. Here’s what a few have had to say.

Ken Peartree, Hewlett Packard DOM — “No other company was willing to use such a creative approach. It was great for us!"

Joe Sasser, DOM — "I challenged Duncan Aviation to create this program as I believe the industry is moving that direction. We performed two separate C inspections on our Falcon 50 and 900EX. We were very pleased with the team's performance and our accounting department loved knowing where we stood before performing the work."

Chuck Baker, Greenleaf DOM— "I have maintained this aircraft for many years, but never been to this level of an inspection. I really don't know what will be found. I do suspect there will be some S-duct cracking and possibly some tank corrosion. Given that, we believe Duncan's Firm Fixed is the way to go!”

Bottom line for us is simple. Duncan Aviation has a tremendous amount of history and expertise with all Dassault airframes that we are willing to take the risk for our customers.

Our relationships with our customers are very important to us. We continually look for ways to enhance and improve their Duncan Aviation experience and are challenging our other teams to pursue offers of Firm Fixed Pricing for other airframe types. Stay tuned.

Let's Talk Firm Fixed Pricing at EBACE

Dale is attending European Business Aviation Convention and Exhibition (EBACE) in Geneva, Switzerland, May 14 – 16. If you have any questions or want to talk about Firm Fixed Pricing for you next Falcon inspection, schedule an appointment with Dale or stop by Duncan Aviation’s stand #456.

Dale Hawkins is an Airframe Service Sales Rep at Duncan Aviation’sBattle Creek,MI, facility. He specializes in the Falcon and Hawker airframes. His aviation career began in 1981.

Tags: Airframe Maintenance, Falcon, firm fixed pricing, airframe corrosion

First Falcon 7X 48-Mos Telescopic Duct Inspections Coming Due

Posted by Diane Heiserman on Fri, Feb 17, 2012 @ 03:10 PM

Contributed by Jerry Cable, Accessories Rep

Falcon 7X 48-Month Telescopic Duct Inspection

Rick Kastl, Duncan Aviation Master Accessories Tech performs a Chapter 5 requirement on Falcon 7X telescoping tubes.

One of the first calendar inspections for the Falcon 7X is the 48-Month Telescopic Duct Inspection. This inspection requires the leak testing, deflection-force testing and extension-force testing of the three telescoping tubes found in each wing of the 7X.

I was contacted recently by a Senior Aircraft Maintenance Manager for one of the first Falcon 7X aircraft registered in the United States seeking assistance in complying with this Chapter 5 requirement. Being a relatively new model aircraft, this was first time I had received a request of this type. Just like all new model aircraft, the tooling and capabilities aren't always available when the first aircraft comes off the line. Oftentimes, they are developed when operators' demands dictate it.

With help from Todd Hoffman, Phu Ngyun and Mark Lepkey of Duncan Aviation’s Machine Shop and Duncan Aviation Accessory Master Tech Rich Kastl, we have been successful in engineering the necessary tooling and test rigs using the Falcon 7X maintenance manual and a set of new 7X tubes.

Duncan Aviation facilities in Lincoln, NE, and Battle Creek, MI, are both Dassault Falcon Authorized Heavy Service Centers authorized to perform all major and minor aircraft inspections and repairs on all Falcon models.

Jerry Cable is an Accessory Tech Rep located at Duncan Aviation's Lincoln, Nebr., facility. He specializes in around the clock assistance with troubleshooting and accessory related technical questions. His aviation career began in 1991

Tags: Parts & Accessories, Falcon

Duncan Aviation Technicians Travel the World in 2011

Posted by Diane Heiserman on Wed, Jan 25, 2012 @ 10:04 AM

In 2011, Duncan Aviation team members made hundreds of trips around the world providing AOG services. While providing the most-needed AOG services to our customers on nearly every Continent, team members also took in some local culture, food and sites.

Berlin, Germany

Berlin, Germany

In March, Scott Shefke, Challenger/Global Tech Rep, traveled to Berlin,Germany, to perform and assess the viability of restoring a Challenger CL 604 to airworthiness status. The project included performing engine boroscopes, performance runs, system operations checks, fuel sampling and general condition of aircraft.

“Berlin is a magnificent city to visit,” says Scott. “It is rich with history.”

Cairo, Egypt

Cairo, Egypt

In Cairo, Egypt, Dan Soderstrom, Master Turbine Engine Mechanic, and Bill Walker, Engine Tech Rep, were in the right place at the right time when one project turned into two. While troubleshooting a faulty fuel control unit on a Hawker 800XP, a local Hawker 850XP operator approached them for assistance in fixing leaking starter/generator seals.

Both Dan and Bill said that everyone they had contact with in Egypt were very nice and helpful. Dan hopes to have more opportunity to see the great city if he gets the chance to go in the future.  

Bordeaux, France

St. Emilion, France

Ron Grose, Falcon Tech Rep, attended the annual Falcon 7X Steering Committee meeting in May, in Bordeaux, France, a beautiful old city located in southwestern France along the Garonne River, surrounded by elite vineyards. As a member of the steering committee, Ron and others oversee the development of the scheduled maintenance program for the Falcon 7X aircraft.

One of Ron’s favorite places to visit was the small village of Saint Emilion. It is a 1,700 year old village which was, at one time, surrounded by a large moat used for protection against the warring tribes. This quaint village had narrow cobblestone streets, great restaurants and many wine tasting shops.

Brisbane, Australia

Brisbane, Australia

Duncan Aviation Fuel System Lead Technician, Jon Abrahamsen, took a week long trip to Australia in May. He was dispatched to repair a wing junction plate fuel leak on a Falcon 2000EX.

Jon used one of his days to drive two hours down to Surfers Paradise, a large tourist beach. He also took the train downtown to the south shore for dinner and a couple of local beers. Jon says the area was beautiful.

Shanghai, China

Shanghai, China

Scott Howell, Airframe Lead Mechanic, along with three other fellow Duncan Aviation team members, traveled to Shanghai, China to complete a crucial fix on a Falcon 7X. Getting tools and equipment through customs posed a challenge, but the team stuck to the task, completing the project early.

On the first full day of their trip, the group made their way to The Bund, a mile long street lined with shopping. A local gentleman led them beyond the glamour of these stores to another area. Here, they had the adventure of walking up steep wooden stairs, entering into random people’s homes, where they bargained with local merchants for various items. It is an experience they will not soon forget. Scott describes the city’s transportation as very convenient and clean. The food was not what he would have suspected, but enjoyed trying the various delicacies of the region. 

Santo Domingo, Dominican Republic

Ned Shanks, Engine Rapid Response Tech out of Fort Lauderdale, FL, made a trip to Santo Domingo, Chile, in October to assist a customer. The #1 engine on their Lear 35 would not start. Having seen this squawk many times before, Ned suspected there was an issue with the aircraft’s igniter box and prepared for his trip with this in mind. This was a very important job because the aircraft was an air ambulance and was scheduled to fly a sick infant back to the United States for medical care.

After arriving, clearing Customs and making it to the aircraft, Ned quickly discovered his suspicions were correct, a failed igniter box. As soon as he complied with the removal and replacement of the box, ground runs and required paperwork, they were airborne and on their way back to Ft. Lauderdale. Shortly after arrival back home, the aircraft was prepped and sent out on another rescue mission.

Tags: Learjet, Falcon, AOG, Hawker, Challenger

Second Falcon 900 Winglet Installation Completed in Battle Creek

Posted by Diane Heiserman on Thu, Jan 19, 2012 @ 01:38 PM

Contributed by Alan Monk, Airframe Service Sales Rep.

Falcon 900 API winglets, photo credit Moni Shafir

API winglets only recently became available for Falcon 900 aircraft.

Photo credit Moni Shafir

Since Falcon 900 winglets became available this past fall, we’ve had good installation activity for the modification in our shops. We’ve done a few at our full-service facility in Lincoln, NE (LNK) and our second in Battle Creek, MI (BTL) is nearly done.

There’s not a lot of difference between the winglets for Falcon 900 and 2000 aircraft, and we have a lot of experience with the 2000s. Although some additional interior access is required to run wiring in the 900s, the winglet kits themselves are fairly similar. There are a few aileron modifications, but otherwise the hardware is essentially the same.

Falcon 900 winglets can easily be installed during a C inspection without any impact to the maintenance schedule. Since the interior has to be removed for the airframe inspection, it makes the wire runs more accessible for the winglet installation, which helps customers cut costs.

It’s also a good opportunity for a dry bay modification, interior refurbishment and avionics upgrades like Wi-Fi or cabin entertainment systems; although more involved projects may impact the maintenance schedule.

Duncan Aviation is the most experienced blended winglets installer for business aircraft. We have performed nearly all of the modifications for the Falcon 2000 fleet, and are experienced in installations for Hawker 800 series and Falcon 900 series aircraft.

Please contact a member of Duncan Aviation’s airframe service sales team for more information.

Alan Monk serves as an Airframe Service Sales Rep. for Duncan Aviation in Battle Creek, MI (BTL), specializing in Falcon and Hawker aircraft. His career in aviation began in 1984.

Tags: Airframe Maintenance, Falcon

Avoid Hawker Landing Gear Exchanges During Maintenance Events

Posted by Diane Heiserman on Wed, Dec 28, 2011 @ 09:57 AM

Contributed by Dan Fuoco, Hawker Airframe Service Sales Rep.

Hawker Landing Gear

Hawker roll-around nose landing gear (NLG) and main landing gear (MLG) used to keep aircraft moving through maintenance.

I’ve worked with Hawker maintenance events for a long time, and I make it my business to make sure everything is in place for an aircraft to deliver on time (if not ahead of schedule). It’s common knowledge that combining Hawker landing gear overhauls with scheduled maintenance and paint saves downtime. What isn’t commonly known is a simple piece of equipment can reduce that downtime by another few weeks.

That piece of equipment is called a roll-around landing gear, which serves as a temporary stand-in for the original gear when it goes in for overhaul during a combined maintenance event.

Roll-Around Landing Gear

Typically, a maintenance event will finish weeks ahead of a landing gear overhaul. Since an aircraft can’t be painted without a landing gear, operators typically have two options: let the aircraft sit for two weeks while the original gear is overhauled, or exchange the gear for another unit. A roll-around landing gear presents a third, more efficient option.

When an aircraft arrives for maintenance, the original landing gear can be immediately replaced with the roll-around gear. This allows the aircraft to be moved through all phases of maintenance, including paint, while the original gear is overhauled. When the aircraft paint process is finished, the original landing gear is usually ready for reinstallation.

2 Weeks of Downtime Savings

I strongly recommend that operators choose a Hawker service center that has roll-around landing gear, especially when planning for a combined maintenance event. Operators will probably save about two weeks of downtime if they work with a service center that has roll-around landing gear available.

Roll-around landing gear are available at Duncan Aviation for all series of Hawker aircraft; Challenger 600s, 601s and 604s; and Falcon 50s, 900s and 2000s. Duncan Aviation has a Hawker Authorized Service Center, and a Hawker-authorized accessory shop for landing gear overhauls in Lincoln, NE (LNK). Please contact me, Dan Fuoco, or a member of Duncan Aviation’s Hawker team for more information.

Dan Fuoco serves as a Airframe Service Sales Rep. at Duncan Aviation’s full-service facility in Lincoln, NE (LNK), specializing in Citation and Hawker aircraft. He started his aviation career in 1974.

Tags: Airframe Maintenance, Maintenance Event Planning, Falcon, Hawker, Challenger

What Projects to Schedule with Blended Winglets

Posted by Diane Heiserman on Thu, Nov 04, 2010 @ 11:55 AM

winglet scheduling

Winglet upgrades can be scheduled with inspections, additional modifications with similar turntimes and prebuy evaluations.

A business aircraft is a corporate workhorse, and an extended downtime for winglets alone isn’t feasible. To maximize the time an aircraft is out of service, the upgrade can be scheduled with an inspection or paired with additional modifications that require a similar turn time.

Falcon 2000 Series Winglet Scheduling

It takes about four weeks to achieve a blended winglet modification for Falcon 2000 series aircraft. Projects with similar (or longer) downtimes that can be worked with winglets include:

  • “C” check (downtime extended by about a week),
  • Dry-bay modification (no additional downtime),
  • Interior refurbishment,
  • Paint refinishing.

Hawker 800 Series Winglet Scheduling

Downtime for Hawker 800 series aircraft is even shorter, about 21 calendar days. Projects with similar (or longer) downtimes include:

  • 24 / 48 month inspection cycles (aircraft age and inspection findings can affect downtimes),
  • LoPreste landing and taxi light modification eliminates the risk of lens melting (no additional downtime),
  • RVSM avionics nose bay modification makes avionics boxes accessible through the nose wheel bay (downtimes vary),
  • Interior refurbishment,
  • Paint refinishing.

Winglets & Pre-buy Evaluations

Pre-buy evaluations also present an opportunity for a winglet modification. It’s an important item to consider, says Gary Dunn, Vice President of Sales at Aviation Partners, Inc. “The modification can be achieved during that same downtime, and it can be rolled into the financing at that time.”

Winglets for both airframes can also be paired with phone systems and interior modifications.

Find out more about Falcon 2000 series and Hawker 800 series winglets at Or contact a member of Duncan Aviation’s Falcon or Hawker Airframe Service Sales team for information about our winglet installation capabilities.

Tags: Winglets, Falcon, Hawker

Winglets: 4 Week Downtime For Falcon 2000 Series Aircraft?

Posted by Diane Heiserman on Wed, Oct 27, 2010 @ 12:11 PM

falcon 2000 winglets

Duncan Aviation's 4 week Falcon 2000 winglet downtime is the result of scheduling the most modifications and developing innovative techniques.

Additional photos are available in the Falcon winglet press release.

Falcon 2000 series winglet modifications take about four weeks, while Hawker 800 series runs about 21 days. How is Duncan Aviation able to quote a four week downtime for Falcons when the rest of the industry seems to be at six to eight weeks? And why the discrepancy in downtimes between airframes? I talked with Dale Hawkins, an Airframe Service Sales Rep. at Duncan Aviation-Battle Creek, Mich. for explanations.

Falcon winglet modifications take longer due to the amount of internal wing work, says Dale. Dropping the planks and adding the reinforcements is time consuming. The Hawker 800 series design allows for most of the reinforcements to be external to the wing, which equates to a shorter turn time. As for Duncan Aviation’s comparably shorter Falcon turn times, projects tend to become more streamlined the more experience a service provider has with them.

Like everyone else, Duncan Aviation began with a six to eight week turn time when the Falcon 2000 winglet modifications were first offered in 2008. The first three projects were a learning curve. Nearly 20 modifications later, we’ve pared it down to four weeks (whether or not it includes a Falcon dry bay modification).

“We’ve done it by scheduling the most modifications, and by working projects back-to-back,” says Dale. “We’ve also developed our own techniques to reduce turn times.”

Both downtimes are relatively short, but they can be scheduled with other projects when an aircraft is down for service. For advice on what projects to schedule with winglet modifications, read next week’s blended winglet blog post.

Find out more about Falcon 2000 series and Hawker 800 series winglets at Or contact a member of Duncan Aviation’s Falcon or Hawker Airframe Service Sales team for information about our winglet installation capabilities.

Tags: Winglets, Falcon

3 Factors That Affect the Value of a Winglet Modification

Posted by Diane Heiserman on Tue, Oct 12, 2010 @ 11:01 AM

hawker winglets

What is the value of increasing your flight capabilities? For Hawker 800 series, winglets allow you to fly non-stop across the US, or comfortably reach Jeddah from Paris. You can also complete shorter missions with greater payload and fuel reserves... without buying a new aircraft.

Photo source:

Residual value, perceived value and fuel savings are important factors to consider when calculating the return on investment for a winglet modification.

1. Residual value.

Aircraft Blue Book values for both Hawker 800 series and Falcon 2000 series aircraft estimate a conservative 75% residual value for winglet modifications, says Gary Dunn, Vice President of Sales at Aviation Partners, Inc. Aircraft with winglets are “worth more and sell more quickly.”

2. Perceived value.

Winglets are quickly becoming a standard. As the number of winglet-equipped aircraft on the resale market increases, Gary speculates it will become increasingly difficult to sell an in-service aircraft with conventional wingtips.

Gary explains that in the case of the Gulfstream II, 70% of the fleet is now equipped with Aviation Partner’s winglets. “It became a standard,” he says. “We’re seeing a similar trend on the Hawker 800 series. It’s becoming a piece of equipment that people expect.”

3. Fuel savings.

Additional value is realized through improved fuel burn. For example, operators who regularly fly longer missions (coast-to-coast or US-to-Europe, for example) can cut their fuel bills significantly. Operators can also fly faster for the same fuel burn, saving valuable time and lowering direct operating costs (DOCs) for their operation.

The longer range, improved cruising speeds and fuel efficiency realized through a winglet modification is far more cost effective than upgrading to an aircraft with similar capabilities.

For tips on managing the cost of a winglet installation, look for next week’s blended winglet blog post.

Find out more about Falcon 2000 series winglets and Hawker 800 series winglets at Or contact a member of Duncan Aviation’s Falcon or Hawker Airframe Service Sales team for information about our winglet installation capabilities.

Tags: Winglets, Falcon, Hawker


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