August 2021

Read the Summer Issue of Flight Levels Out Now

The Twin Commander community has a reputation for great service and support, in part because of the work of experts who have spent entire careers dedicated to the fleet. In the latest issue of Flight Levels we meet Mike Merek, who recently retired after many years maintaining a few very special Twin Commanders. We also profile well-known Twin Commander Factory Authorized Service Center Eagle Creek and its longtime leader, Matt Hagans. And in Market Report we speak to Bruce Byerly, who grew up maintaining, flying, and buying and selling Twin Commanders, as well as market expert Jim Worrell who has taken over sales at Eagle Creek for Hagans. Plus, make sure to check out Twin Commander Aircraft’s Brian Harbaugh’s “From the Factory” message, tips on operating your Garmin equipment, the current requirements on international traveltax tips, and more.

New Option for Dash 10T Conversions

National Flight Services, Inc., the second oldest Twin Commander Factory Authorized Service Center and the oldest Honeywell TPE331 service center, was recently selected by Honeywell as the exclusive Honeywell Heavy service center authorized to perform the Dash 5 to Dash 10T engine conversion. National Flight Services has long been known as a premium service center to send TPE331 engines for overhaul or repair. With the announcement, a National Flight Services representative said, “This is the conversion that Twin Commander owners with Dash 5 engines have been waiting for.” The Dash 10T conversion has many benefits, including faster rate of climb, increased cruise speed, better fuel efficiencies, better performance, and reduced maintenance costs for HSI/GBI. “Bottom line, this conversion will increase the value of the aircraft,” he said. Interested operators should contact Mike Converse, director of sales, at [email protected] or 567-868-9902.

Factory and Service Centers Work in Tandem

Twin Commander Factory Authorized Service Centers have a close relationship with the staff at the factory. Information flows both directions, as service centers provide customer feedback to the factory and the factory provides updates and critical information directly to the service centers. The two also collaborate on product development, as illustrated by recent work at Legacy Aviation. The factory has been working on a new part that customers have requested, and engineering was ready to test its installation in the field. It’s one thing to design a part based on drawings and assumptions, but critical information always comes from installing a new component on an airplane in the field. For that the team at Twin Commander Aircraft traveled to Legacy Aviation, a Twin Commander Factory Authorized Service Center in Oklahoma. There they worked closely with experienced technicians to fit the component on an airplane and gather information that will help to better understand everything from how well the new component fits to how effective the installations instructions are. It’s one of the many benefits of maintaining close connections between the factory and the service center network.

EAA AirVenture a Big Success for Aircraft Belts

Some of the wardbirds ABI saw at AirVenture. Photo courtesy of EAA AirVenture.

Twin Commander Aircraft sister company Aircraft Belts, Inc. (ABI) exhibited at this year’s EAA AirVenture in late July, and by all accounts it was a successful show. EAA said more than 10,000 aircraft – a record number – flew in to Oshkosh’s Wittman Regional Airport and other nearby fields for the show, and the 608,000 attendance figure nearly reached 2019 levels, the last year the show was held. The coronavirus pandemic shelved last year’s show, and it was clear from the enthusiasm of attendees and exhibitors that everyone was happy to be back. “It was great to see everyone again and meet so many new customers,” said Twin Commander’s Brian Harbaugh. “It was just an awesome show.” Harbaugh and the team are headed to the annual NBAA convention in Las Vegas October 12-14. Look for them in booth 864.

Maintenance Class Set for September

In addition to extensive hands-on experience in maintaining Twin Commanders, many technicians from the service center network have also attended type-specific training. The next eight-day class is scheduled to begin September 13. The class is taught by Twin Commander expert Mike Grabbe at Eagle Creek Aviation in Indianapolis. “Open wide and here it comes from a fire hose,” said Grabbe. Every system on the airplane is covered, including environmental, hydraulic, panel, engines, electrical, fire suppression, and more. Grabbe said the only thing he doesn’t cover is interiors. For more information, or to sign up, call Eagle Creek at 317-293-6935.

Buy One, Get One on O-Rings

The main landing gear retract cylinder O-rings are a common wear item, so why not save some money when replacing them? From now until the end of September, buy one O-ring overhaul kit and get one free as part of Twin Commander’s Spend and Receive program. Buy the left- or right-side kit and get the kit for the other side free. Either way, you win. Make sure to ask your Twin Commander Factory Authorized Service Center for kit number 145-O to take advantage of this offer. Limit two per serial number.


July 2021

A Focus on Hot Weather Operations

Record temperatures in the United States and Europe, and news out of Japan of extreme conditions for Olympic athletes make it clear the northern hemisphere is in the grips of extreme heat events. High temperatures can have big impacts on airplanes, especially as it relates to performance. Here’s how:

Beware of Density Altitude’s Sly Impacts

For many pilots who fly to airports primarily at lower elevations, density altitude is something that was covered in private pilot ground school, and probably not considered since. But the impact of heat, humidity, and elevation can quickly overwhelm an airplane’s ability to takeoff and climb. Consider the 500S. At sea level, gross weight, no wind, the takeoff distance to clear a 50-foot obstacle is only about 1,800 feet. Even a really hot summer day of 35 degrees Celsius (95º F) will only increase that distance to about 2,100 feet. Head to the mountains and things change quickly. That same standard day will take about 3,100 feet to clear the obstacle at an airport sitting at 6,000 feet. Now raise the temperature 20 degrees above standard like you did at sea level and it will take 3,600 feet, a pretty significant difference. More importantly, if an engine fails, perfect technique will get you climbing 80 feet per minute on a standard day and only about 25 feet per minute on a +20 day.

As you would expect, turbines do better, but they aren’t immune to the impacts of density altitude. In a 690A, our same 6,000-foot airport would require a little more than 3,000 feet on a standard day and a bit more than 4,000 feet on a +20 day. Single-engine climb is where the turbines really shine. A standard day at 6,000 feet sees a single-engine climb rate of about 800 feet per minute, whereas on a +20 day, the book says we should still be climbing at 650 feet per minute. Regardless of the performance improvements over a piston, if the airport is high and it’s summer, the performance charts should be the first place you turn.

Firefighting Ramps Up Early

Photo by Mike Biden

With the higher temperatures of summer comes the threat of wildfires. Conair, a Canadian aerial firefighting company, operates seven Twin Commanders as bird dogs and two more on parts and supply runs. A company representative provided this report:

The fire season this year in Alberta has so far been fairly average, enabling the province to release on loan the Twin Commander bird dog to British Columbia to support operations from Castlegar. Similarly, the Yukon Twin Commander, which was based in Whitehouse, has been deployed to Revelstoke BC to assist with forest fires in the region. And, after the recent heat dome and a drier-than-average June and July, British Columbia is experiencing an extreme fire season, with burning conditions approximately three to four weeks ahead of schedule. Recent weather and fuel conditions have made initial attacks challenging. The Twin Commander bird dogs are flying throughout the province, with the Okanagan, Kootenays, and southern Cariboo regions experiencing a significant number of fires-of-note. There are over 1200 fires this year to date, with over 250 active fires. The rest of the fire season outlook doesn’t look promising and isn’t likely to slow down until the rain – or snow – arrives.

Owners of 500s Can Order Supplements from Twin Commander

Sometimes it’s so hot that even the writers of the flight manual couldn’t have imagined it. When the temperature exceeds the values listed in the performance charts it can turn you into a test pilot, a situation no pilot wants to be in. For pilots who routinely operate out of hot and high environments, or those wanting better performance data, Twin Commander Aircraft offers flight manual supplements. Owners of 500S models can ask for supplement 12, 500U owners need supplement J, and owners of 500B models can ask for supplement K. Inside you’ll find performance figures beyond what’s in the standard flight manual, including those for takeoff, climb on one engine and two, landing, and more. Call Twin Commander Aircraft at 919-956-4300 and ask for engineering librarian Pam Moore to get yours.

Heat Can Wreak Havoc on Systems

Density altitude isn’t the only consideration for operating in hot weather. Our airplanes also behave differently in the heat. According to Andre Pridgen, service center manager for Twin Commander Factory Authorized Service Center Aero Air, brakes and prop hubs are a consideration as well. He said brake caliper o-rings tend to fail and leak more when it’s hot, so keep an eye out for the telltale seepage around the landing gear. Aero Air keeps a spare caliper overhauled on the shelf ready to go for this reason. And pilots who tend to ride their brakes or use them more forcefully on landing can expect shorter cycles between maintenance.

Pridgen also stressed that the Hartzell propeller hubs with Aeroshell 6 or 7 grease tend to leak when the temperature starts to rise. Aero Air will see it first in the hangar, and especially on the ramp. And when the grease is new and the prop recently serviced, expect it to happen even more. “I get four or five calls a month from pilots asking about it,” he said. Seeing fluid on the ground near the propellers is always a bit disconcerting, but in most cases Pridgen said it’s harmless.

Most importantly he said it’s critical to watch your starting temperatures. Things happen faster when it’s warmer, and it’s much easier to exceed temperature limits. By keeping a close eye on the engine temperature during start you can prolong your engine’s life and avoid a dreaded hot start.


May 2021

Service Center Rebrands

Twin Commander flown by Erick Teeters & John Kelley.

A Twin Commander Factory Authorized Service Centers recently changed branding, but doesn’t expect a change in the level of service offered to customers. Gemini Air Group, the most recent addition to the network, was sold to the TAG group of companies and will now be known as Keystone Aviation. Keystone will be the branded arm of the service, charter, and support group, while TAG Private Hangars will take over branding for what was Gemini’s large hangar footprint at Scottsdale Municipal Airport outside Phoenix. Greg Laabs remains the director of maintenance, and he said the techs and the Gemini staff are still in place. He’s excited about the transition, and what the new owners are bringing to the company, including a pressurization cart that will enable them to do pressurization testing and troubleshooting.




Enviro Modification Offered as Custom Kit

Owners and operators of certain models of Twin Commanders looking to upgrade their environmental systems and move away from Sundstrand have a trusted option with Custom Kit 183K. This complete solution changes the bleed-air environmental system from a Sundstrand to one made by Enviro, and is available for Models 690C serial numbers 11600 through 11742; 695 serial numbers 95000 through 95087; 690D serial numbers 15000 through 15042; 695A serial numbers 96000 through 96100, and all 695Bs. The kit estimates 300 hours for the change.
To learn more about the kit or to make an order, contact aTwin Commander Factory Authorized Service Center. You can find the full list online.

Got the Juice?

Batteries are always taken for granted. We expect them to work and only think about them when they fail. Replacements of Twin Commander batteries are readily available from both Gill Batteries and Concorde Battery. Recently the factory has received questions about how to source new batteries, and even helped an owner with advice and parts to fix corrosion caused by a long-ago leaking battery. Gill offers replacement part 7638-44, a sealed battery, and Concorde offers replacement part RG-380E/44. Both companies have extensive information on their websites about battery maintenance to help extend the life of your investment.

Aircraft Belts Offering Oshkosh Pre-Show Special

From now through the end of EAA AirVenture on August 1, owners can receive 5 percent off the catalog price on Aircraft Belts’ Twin Commander restraint systems if they mention the show when ordering. Aircraft Belts will be at the show from July 26 to August 1, showing off its wide range of available styles, colors, and buckle treatments for models 500S, 685, 690, 690A, and 690B. Now available off-the-shelf, prices are lower than the custom restraints that were previously available. Paying for safety isn’t always fun, but with Aircraft Belts you can upgrade the look of your belts, improve the safety of your aircraft, and bring more personalization to your cabin and cockpit. Check out the full catalog or see them at the Exhibit, Booth #3045, Epic Exhibit Hangar C.


April 2021

Spring Flight Levels Online

Flying one airplane for 34 years is notable enough, but in public flying it’s even more rare. Bruce Stamey has had the distinction of flying the same Shrike for the State of Louisiana since he was hired in the early 1980s. It’s also rare to hear about a Twin Commander Factory Authorized Service Center changing hands. Read about Bruce Byerly’s recent acquisition of the Naples Jet Center. He and Eagle Creek’s Jim Worrell see continued improvement in the aircraft sales market.  Plus, this issue is packed with tips of flying, owning, and operating your Twin Commander. Read about fuel bladder installs, treating your piston engines well, getting the most of your Garmins, and where to fly as the world slowly reopens. That and more is all in the Spring issue of Flight Levels now online.

Eagle Creek Installs First DFCS 3100 Autopilot

The first Genesys Aerosystems digital 3100 autopilot has been installed in a Twin Commander. Eagle Creek Aviation worked with Genesys and Don Vollum, owner of a 980, to install and certify the first one. “The altitude capture and vertical speed hold are the best features, along with the overall precision with which the 3100 flies the airplane,” Vollum said. Taking on a new STC project can be fraught with challenges, but Vollum said the process was smooth. Eagle Creek has extensive experience with installs used as the basis for certifications. The company owns the Garmin G950 STC for Twin Commanders, and it helped develop the Dash 10 engine conversion and Radome to Tailcone refurbishment program. “I don’t think there is another shop I would trust for the first installation of an autopilot,” he said. The 3100 is a three-axis attitude-based digital autopilot with envelope control and electronic stability. It is now approved for 690, 690A-D, 695, 680W, 681, 500, 500A, B, S, and U, and 560A, E, and F models.

Legacy Aviation Answers the Call in Mexico

Great service sometimes means going where the customers are. That’s what Legacy Aviation Services recently did for one of its longtime customers. The operator, based in Mexico, flies an 840 that Legacy Owner RJ Gomez says is pristine inside and out. A broken windshield grounded the airplane at its home base in Culiacan. Schedules aligned as Twin Commander Aircraft had a windshield in stock as soon as Legacy had an opening on its shop schedule. Legacy sent a technician to uninstall the previous windshield and prepare the installation. Two days later the parts arrived, and in a total of five days the job was done. Gomez said the customer also operates a Learjet and a Hawker, but that the boss loves his Twin Commander. Legacy Aviation Services is a Twin Commander Factory Authorized Service Center, and is a certified repair station by the Mexican aviation authority.

Blue Goose Flies On

It’s the airplane that started it all. When Bert Bantle and Emmett Morris flew the prototype L-3805 that would become the first Twin Commander nonstop from Oklahoma City to Washington, D.C. on one engine, it made the airplane a sensation. The airframe was dubbed the Blue Goose, reportedly after the fruit company where they sourced some of the wood. From 1974 to 2006 the airframe sat on a pole at the state fairgrounds. It subsequently went to a technical school, where Tom Ray and Kenny Payton, engineers who worked at the Rockwell/Gulfstream factory, knew the history of the airplane and used their sheet metal classes to help restore it.

Between those efforts, and now with the support of Dave Amis and others, the Blue Goose has a strong future. Amis worked with the city of Bethany, which owned the airplane, to transfer the historic artifact to the Oklahoma History Center. He has gathered local businesses and Twin Commander supporters, and is soon planning to mate the wings, weld the landing gear, paint it, and eventually have it installed on a pedestal in a park immediately south of the Wiley Post airport in Oklahoma City. Amis, whose family has been involved in Commanders since the beginning, said it means a lot to him to help restore and highlight the airplane. “I remember this airplane in the early 1960s,” he said. “I would beg my dad to drive by the factory to see it.”

Supporters who want to help the cause can learn more at Amis’ GoFundMe page.

February 2021

Naples Jet Center Building New Hangar

Naples Jet Center, a Twin Commander Factory Authorized Service Center, is poised to become the biggest corporate operator on the busy Naples airport in southwest Florida, after the recent approval of its plan to build a hangar and office complex totaling 45,000 square feet. The hangar will be large enough to accommodate up to three Global Express business jets, and there will be offices for visiting pilots and the company’s corporate flight department. When combined with Naples Jet Center’s current 80,000 square feet of space, the expansion will give the busy service center more than 120,000 square feet of total operating footprint. The project received approval in mid-February, and is now in the development and design phase. Owner Bruce Byerly is excited about the expansion, and thinks the Naples area has even more growth potential. “We could use the space yesterday,” he said. You can read more about the Naples Jet Center in the upcoming spring issue of Flight Levels Online.

Spend and Receive on Bungees

From now to the end of March, buy one landing gear bungee and get one free as part of the Twin Commander Spend and Receive Promotion. Every model of Twin Commander uses two bungees on each main landing gear to help gravity, the emergency gear extension system, and the hydraulic system to extend the main landing gears over-center and into the down and locked position. If you can squeeze a bungee with your thumb and forefinger and the two sides touch, it’s time to replace it. Now, Twin Commander is offering owners and operators a free bungee when they purchase and install one at a Factory Authorized Service Center. Ask for part number 9044 and receive a little something when you spend a little something.


Did You Know?

Every airplane has a demonstrated crosswind capability or crosswind limitation, and most light airplanes use one number. But certain models of turbine-powered Twin Commanders have two values—one for takeoff and one for landing. The 840 and 1000 both list the maximum demonstrated crosswind velocity for takeoff at 30 knots and landing at 27 knots. This practice of different values for takeoff and landing is more common in transport category aircraft.