Oregon based jet manufacturer Stratos Aircraft has designed and developed a prototype VLJ (very light jet) aircraft that, according to their website can achieve, what until recently wasn’t a feasible possibility for other aircraft of its kind. The appropriately named Stratos 714 has the capability to traverse the entirety of the United States, from the southeast to Seattle in 7 hours.
The result of an amalgam of cutting edge technology, space-age composite materials, and advanced manufacturing techniques, the Stratos 714 has the highest thrust-to-weight ratio of comparable VLJs. Some of the aircraft’s principal features include the fact that it can climb to altitudes near 40,000 feet and achieve speeds of 400 knots over an impressive 1500 nautical mile distance. The aircraft will be marketed as multi-use and is designed to serve as a travel alternative for the individual, corporate or air taxi pursuits.
The concept of the Stratos 714 was originated roughly 10 years ago while the aircraft’s chief innovators were enjoying a cup of coffee at a local establishment. President and CEO of Stratos Aircraft Michael Lemaire had initially met Chief Technology Officer Carsten Sundin a decade before while Sundin was working with Lancair International and the two men had managed to stay in touch.
A native of Oslo, Norway, Carsten Sundin had been an intern with Lancair while studying aerospace engineering at CU Boulder. Upon his graduation in 1993, he continued to design for Lancair and ultimately became the engineering manager on the Lancair Legacy 2000. He left Lancair for Epic Air in 2003 and then in 2005, started his own consulting agency. For the last 25 years, Sundin has been a key designer in the development of aircraft for many aviation companies.
Entrepreneur Michael Lemaire has been with Stratos for the last 10 years and works closely with technicians and engineers in the conception, design, build and testing of aircraft. He is also director of MAX Design, a developer of computer software that implements design assisted alternatives for the marine and aviation realms and has been operations director for X-Air LLC for nearly 30 years. The latter is an LSA (light sport aircraft) and ultralight aircraft manufacturing company.
Lemaire has indicated that he has always had an interest in aviation. His initial contact with flying was through the use of a hang glider after which he built a Lancair using a kit, but when his interest turned toward flying jets, he couldn’t locate one to suit his taste.
Hence the conceptualization of a particular VLJ whose origins are based in a notion sketched by Lemaire on the coffee shop napkin during the meeting with Carsten Sundin. Both men were interested in developing a VLJ that was capable of an increase in cruise speed and ability to travel farther distances. This meeting of the minds thus launched the inception of the development process of the Stratos 714.
Lack of resources needed to further implement the process to fruition caused the development stage to stall until 2012. Attempts to garner interest in the aircraft at the EAA AirVenture , which included a 3d printed wind tunnel model and a fiberglass mockup cabin, succeeded in ultimately generating enough buzz that the team was able to secure some investments and reignite the process. In 2016, the Stratos 714 proof of concept aircraft took off on its initial flight and in July of the following year, it’s prototype was unveiled at AirVenture 2017 in Oshkosh, Wisconsin
EAA’s AirVenture is an event that draws thousands of aviation enthusiasts from all over the world and on the day of the event in July of last year, the Stratos 714 quickly attracted the attention of the crowd. Following its debut, Lemaire addressed attendees and recounted the tale of the aircraft’s journey, from concept to its current evolution and detailed what was next in the development stage of the aircraft.
He said that the initial objective was to develop a jet that could fly at 400 knots over a range of 1,500 nautical miles, comfortably seating four people at an elevation of 41,000 feet and that those aspirations and the capability of the aircraft to ultimately achieve those numbers is swiftly becoming a reality. Throughout subsequent interviews, he also intimated that the aircraft was still in the development phase and that further tests and certification was needed.
Immediately following AirVenture, the team was still involved in tweaking the aircraft’s design which originally consisted of an 11.5-foot-long, 170 cubic foot cabin that featured four seats and an optional fifth seat as was demonstrated in the prototype aircraft that was unveiled at AirVenture. The Stratos 714 of the present day is slightly longer at 207 cubic feet, has the capability to safely and comfortably seat six and the implementation of a longer pressure vessel has forced the center of gravity forward, resulting in a more flexible loading envelope.
The aircraft’s three-part airframe features composite construction on the forward pressure vessel, wing, and tail, while the power plant is housed in a chromoly steel truss with composite fairings. The Stratos 714 composites consist of Toray woven carbon-fiber cloth pre-impregnated with resin and a variation of carbon fiber, Nomex honeycomb, and carbon fiber sandwich designed to increase flexibility without being weight-bearing.
A considerable number of aircraft manufacturers have started to switch to carbon composite airframes as they offer many advantages over aluminum, especially in the case of aerospace development and design. For example, composites are adept at handling tension loads more effectively. Composites can be manufactured and placed as a solitary piece, as in wing design, therefore no future replacement to fasteners or joiners are needed. Composites allow for more equitable weight distribution, they are strong, yet malleable and they will absorb vibration.
Stratos has reiterated as much regarding their choice in utilizing the benefits of composites in the Stratos 714 design on their website. They additionally mention that composites do not corrode and that the state of the art material supports optimized compound curvature design with less drag.
The Stratos 714 is being developed with the operator of the craft in mind. This is one of the reasons they selected a single engine. Single engine aircraft are safer for operators as well as passengers, have lower acquisition, operating, and maintenance costs and are simpler to operate.
The proof of concept aircraft is powered by a Pratt & Whitney JT15D-5 engine. Once they have obtained certification, the Stratos 714 aircraft will feature the Pratt & Whitney PW535E. Sundin has said that documents and testing have been set up to accommodate the certification effort, but additional funding may be needed to achieve this objective.
As of last year, the team wasn’t certain how much they would need from investors to acquire type certification, but the numbers were fast approaching the 150 to the 200-million-dollar mark. Sundin had a notion that they could design and build a few kits to sell. The kits would be powered by the same engine as the proof of concept model and would help to not only offset fixed costs but also could serve to inspire interest in the aircraft. The company currently has the infrastructure to support a full kit aircraft company.
If Stratos should secure the funding they need to achieve certification, they will be considering a price point for the aircraft to be around 3.5 million overall. This price point’s major contributor is the nearly one million-dollar Pratt & Whitney PW535E engine. However, Sundin is of the mindset that the 3.5 million price may be too conservative. This is due in large part to the exclusive features of the aircraft in relation to its capability to travel the 1500 nm range, at a cruise speed of 400 knots with a full payload.
That said, the team has their work cut out for them. Not only is competition for lower-priced aircraft fierce, the VLJ startup realm can be harsh despite the numerous advantages of these type aircraft to deliver faster speeds with better fuel economy. While they await funding, the team is remaining hopeful.
According to a press release on the company’s website, the second proof of concept 714 was in the development stage as of October of 2017 and is expected to take off on its maiden test flight in late-2018.
To gain more insight into what may be next for the development team and the Stratos 714, we reached out to Stratos. Representatives have indicated that their goal going forward is to certify the aircraft within three years of obtaining the funding for certification. Once certification has been achieved, they will start the delivery process.
As of yet, they have not started taking orders for the aircraft. This is in keeping with a statement President and CEO Michael Lemaire made previously, indicating that he isn’t comfortable taking deposits while an aircraft is currently in the development stage. The aircraft will make another appearance at EAA AirVenture this year. Look for them near the admission gate in booth 15 and 16.
A couple of things are certain, Stratos is playing it close to the vest in releasing information about their VLJ. Not only are they invested in the developing and building of an airplane but a mystery as well. They have certainly piqued our curiosity and that of various other industry insiders who will be on the lookout for new developments regarding the light aircraft.
The team plans on delivering exciting news regarding the latest rendition of the Stratos 714 to AirVenture 2018 coming this summer. Fans of the aircraft will be turned skyward in an effort to see it fly and perhaps an investor or two will take notice.
Photo Credit: Stratos