Products, Services

Essential Equipment: Window and Door Modifications 

By By Clifton Stroud | July 2, 2014
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In the case of most helicopter door and window modifications, necessity is certainly the mother of invention. An independent company talks with operators, surveys the market, and designs a modification that makes a product better or easier to use. Air tour operators want maximum visibility for passengers, so the OEM door is removed and replaced with a large window. This applies in law enforcement operations as well, where visibility is important. A door won’t stay open, so someone designs a simple fix, has it STC’d, and markets it to the industry.

Many of the modifications independent shops have designed over the years have proven to be so popular that they have been incorporated by helicopter manufacturers, such as Bell, making it more of a challenge for some of modification shops to come up with new and innovative products. However, there is still a strong market for window and door modifications on almost every make and model of helicopter. There is always a market for an improved and better product.


Aeronautical Accessories (Bell Helicopter)
Piney Flats, Tenn.

Aeronautical Accessories, a division of Bell Helicopter, offers more than 4,000 different replacement parts and accessories for Bell, AgustaWestland, Enstrom, Airbus Helicopters, Hiller, MD, Sikorsky, and Robinson – everything from lights, floats, ground-handling wheels, doors, landing gear parts and skids to improved visibility windows. The company owns 360 STCs and has been in business since 1979.
Bell recently announced that it had received an STC for its new Bell 407 polycarbonate windshield, which will be distributed through Aeronautical Accessories. The windshield is impact resistant, offering better impact performance compared to acrylic windshields. It deflects objects away from the cockpit and significantly decreases the likelihood of something breaking the windshield upon impact. Designed as a replacement kit for existing Bell 407/Bell 407GX models, the kit comes with a mounting system of composite edging, adhesives and fasteners to provide increased flexing. The strapped edging and independent corner support design allow for improved impact resistance. The kit is also available for installation on new aircraft during customization.
The high-visibility crew door kit for the Bell 407 is a modification to the existing door that incorporates an expanded and bulged window that provides 30 percent more viewing area. This kit is designed for law enforcement and any applications where enhanced visibility and crew shoulder room are important. It can be used in conjunction with the bulged skylight kit.
Aeronautical Accessories has earned its AS9100 certification, which is an internationally recognized quality management standard for aviation.

Armour of America
Auburn, Ala.

Armour of America designs and manufactures lightweight, custom aviation ballistic protection modifications for helicopters, including curtains, blankets, and shields. The company offers lightweight armor solutions using composite materials, specialty steel and ceramic tiles. These materials provide the required ballistic protection at a minimum weight, consistent with cost effective design. Areas covered include the cockpit floor and doors, cabin floor and walls, chin bubble, crew seat bottoms and backs, gunner stations and transmission walls. Armour of America also instructs operators on how to maintain, install and remove the armor panels. The company has CAD drawings and kit designs for most helicopters and is willing to make design modifications based on a customer’s changes. Their products are in service with operators in Australia, Canada, Chile, Colombia, Brazil, Hong Kong, Spain, Sweden, Thailand, and New Zealand.  To date, they have equipped more than 300 helicopters with armor.

Dart Aerospace
Hawkesbury, Ontario, Canada

Dart Aerospace has more than 700 STCs to its credit, with 5,000 products sold in more than 120 countries. They support all types of civil and military operators and all major helicopter OEMs, completion centers, and MRO facilities with an assortment of aftermarket products, accessories, spare parts and tools including flotation systems, landing gear, interior and exterior accessories, cargo expansion modifications, external loads, cable cutters and filters.
The company recently received a European Aviation Safety Agency (EASA) STC for its EC145 skidtubes, and FAA approval for its BK-117 heli-utility-basket. The skidtubes’ central I-beam web absorbs most of the impact on landing so the tube maintains its integrity. The Dart heli-utility-basket is made of corrosion-resistant stainless steel, coated with a high-gloss, scratch-resistant white finish. A self-locking handle keeps cargo secure during flight, and a bolt-on installation allows quick installation and removal of the basket.
Dart Aerospace works closely with the FAA, EASA, Transport Canada and other authorities to obtain the necessary certification approvals.  

Paravion Technology
Fort Collins, Colo.

Paravion has a rich history in the rotary wing door and window modification business. The company started operations 30 years ago by designing and building pneumatic door openers (PDO), now standard equipment on all helicopters. Paravion also built the original scenic, or bubble view, windows for the A-Stars operated by Papillon Helicopters. By cutting the center out of the door and installing a large window, Papillon enjoyed a marketing advantage over other air tour operators without the scenic windows. Many of the modifications Paravion has designed over the years have proven to be so popular that they have been incorporated by helicopter manufacturers, making it more of a challenge for all the independent shops to come up with new and improved mods.
One area that the OEMs have not touched is pneumatic door opener kits, still a mainstay business for Paravion. The company manufactures PDOs for the MD 500, and for Bell for its UH-1s. The kit holds the helicopter door open during run-ups so the rotor wash will not move the door around. They are easy to install, with one bracket on the door and one on the floor.

Soloy Aviation Solutions
Olympia, Wash.

Soloy started operations in 1969 and earned its reputation converting piston-powered Hiller helicopters into turbine-powered aircraft. The company engineered and installed these turbine conversions in more than 170 helicopters. Soloy applied the same conversion concept to the Bell 47. More than 140 of these units were installed by operators, although Soloy no longer owns the STC.
Soloy’s Vista View doors for the Bell 206L, L1, L3 and L4 are designed for sightseeing tour operators. By almost doubling the window areas, passengers have unobstructed views of all the terrain. The large-area windows are built into new doors, which easily replace the existing standard production doors. The fixed panel between the two doors on the right side of the helicopter is the only aluminum skin component; the additional five panels are manufactured using epoxy resin-reinforced glass fiber. Law enforcement and SAR operators use the large area-windows in the two forward positions.

Tech-Tool Plastics
Fort Worth, Texas

Tech-Tool Plastics is a small family owned business that manufactures a full line of replacement windows for Bell, Eurocopter, Schweizer, MD Helicopters and Robinson. Owner and founder John Wilson got his start by designing plaster mockups and precision fiberglass tooling for Bell, then turned to manufacturing helicopter replacement windows. The company serves both the civilian and military markets internationally.
For the past three years Tech-Tool has manufactured new windows for the EC120 and 130, with an improved windshield and reinforced edging. For the EC135, Tech-Tool’s camera window is a popular modification both in the U.S. and Europe and is used frequently for aerial photography and law enforcement operations. Tech-Tool also makes a vertical sliding door for the A-Star AS350/355 that provides visibility and access for ENG operators, law enforcement, air tours and aerial photography. It is available as either a left hand or right hand door, opening from top to bottom and sliding down.
For the Robinson R22 and R44, Tech-Tool has custom-made door assemblies that offer full-view windows, ideal for air tour operators. The windows have the added benefit of providing extra shoulder and elbow room for pilot and passenger. A four-point locking mechanism seals the door to the frame. Turn-around time is six to eight weeks. 

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