The Future of Advanced Air Mobility

In January 2018, start-up Airspace Experience Technologies (ASX) unveiled a scale model of its MOBi-One tiltwing aircraft and by December 2018 it reported that it had flown five sub-scale concept vehicles, including one-third and one-fifth scale models. In September 2019, the company said that it intends to begin hover flight demonstrations with a full-scale model in March 2020, followed by all-modes flight trials starting in March 2021. It intends to have a fully defined prototype ready by March 2022 and claims that it will be able to begin demonstration flights by 2022. However, this timeline appeared to have been pushed back following an announcement made in February 2020 about a partnership with Spirit AeroSystems (see below).

ASX said then it hoped to have the MOBi-One operational for cargo applications in 2023 and for passenger carrying operations in 2024. Its website suggests that it will be directly involved in operations, with plans for a flight booking app. 

Privately owned ASX was formed in April 2017. In January 2018, the company unveiled a scale model of its MOBi-One tilt-wing aircraft and by December 2018 it reported that it had flown five sub-scale concept vehicles. Since the start of 2019, the company has been seeking to build the first full-scale MOBi-One prototype. In May 2019, the Detroit-based company launched parallel funding rounds under U.S. Securities and Exchange Commission's CF and D regulations in partnership with SeedInvest to raise $8 million to support development work. According to SeedInvest, ASX had raised just over $761,000 prior to the latest funding round and has 11 employees.

In June 2019, ASX signed a memorandum of understanding with transportation and logistics group TPS Logistics to evaluate market opportunities for using eVTOL aircraft in cargo-carrying applications.

On February 17, 2020, ASX announced the signing of a memorandum of understanding with Spirit AeroSystems to jointly develop the MOBiOne. Spirit will be involved in design and manufacturing work, as well as providing experience in the FAA type certification process. The announcement did not include any further details on the timeline for the program. It did state that in March 2020, ASX intends to launch a Series A funding round. This had been planned to begin before the end of 2019, and at that time, the company indicated it was hoping to raise $6 million in order to take it through to the end of the preliminary design phase of the program. ASX co-founder Dr Anita Sengupta told FutureFlight that the company is now building a full-scale testbed vehicle that it aims to fly "within 12 months." At the same time, it is also working on an engineering design version of the Mobi-One that will be closer to the production version of the aircraft. Previously, ASX has said that it will have the aircraft certified to start cargo flights in 2023 and passenger-carrying operations in 2024.

On January 27, 2021, CEO Jon Rimanelli, provide a program update to the Vertical Flight Society. He said that the design for the planned aircraft was significantly reworked during 2020 so that it will only takeoff and land in vertical mode, only use the wing during the cruise phase of flight. The aircraft, which now goes by the name Sigma Six, has a shorter wing (38 feet) and six repositioned rotors in place of stacked co-rotating propellers. He said that the change had largely been driven by the need to reduce the cost of the aircraft and also due to difficulties in managing noise.

The ASX team were aiming to finalize the performance of the new propulsion and thermal management system by the end of the third quarter of 2021 with a view to achieving a flight demonstration during the third quarter of the year. It is unclear whether these revised plans will pushback an earlier timeline target to fly a full-defined prototype in March 2022 in anticipation of initial type certification by the end of 2023. Rimanelli also referenced plans for a possible hybrid-electric version of the eVTOL offering extended range of up to 200 miles, compared with 90 miles for the all-electric model.   

Rimanelli explained to FutureFlight that the ASX engineering team opt for the fundamental configuration change away from stacked co-rotating rotors because, "the price we had to pay to lift the weight was quite high, given the state of the electric architectures available. As of mid-February 2021, the company was assembling the main chassis and aimed to integrate flight controls by the end of the second quarter, ready to start tethered flight testing in the third quarter. The design changes have pushed back the program's timeline, with the revised aircraft now expected to enter service for cargo flights in 2024, followed by possible passenger operations in 2026.

Rimanelli explained that the MOBi-One program name is "being retired" and that Sigma Six will be the brand name for the aircraft.



first delivery

ASX says passenger-carrying flights in its MOBiOne aircraft should begin by the end of 2024.


first delivery

ASX says cargo-carrying flights by its MOBiOne aircraft should begin by the end of 2023.

test flight

First all-modes flight of full-scale MOBiOne model
Missed Projection

test flight

First hover flight of MOBiOne full-scale model
Missed Projection


On February 17, 2020, ASX said that it intended to launch a Series A funding round during March 2020. This had previously been planned to start before the end of 2019. At that time, the company indicated it hoped to raise $6 million. 


Our objective assessment of this program’s probable success.

FutureFlight assesses the probability of success for a new aircraft program by considering the following criteria:

  • Total investment funds available in proportion to the anticipated cost of getting an aircraft certified and in service
  • A company’s in-house capability (in terms of numbers of engineers, technical staff, and customer support teams)
  • The past experience of the company and its senior leadership in developing aircraft
  • The caliber and past experience of key program partners
  • Whether key aircraft systems have been selected and are available for use
  • Whether the preliminary design review has been completed
  • Whether the design for the full-scale prototype has been completed
  • Whether the type certification process has been formally initiated with an appropriate regulator
  • Whether the company has achieved a first flight with a full-scale prototype
  • The number of hours logged in a flight test program
  • Whether type certification has been achieved
  • The number of orders and commitment received for the aircraft
  • Whether the company has adequate facilities to begin series production of the aircraft
Our Methodology

ASX makes ambitious claims about its ability to bring the MOBi-One aircraft to market as early as 2023, given that it has not yet achieved a first flight with a full-scale prototype of the aircraft. It's ability to to finance the development program seems to hinge entirely on the success of a new $6 million Series A funding round that was due to start in late 2019, but was subsequently pushed back until March 2020. As of late 2019, the company only had 11 employees and very limited in-house engineering capability.

The program timeline does seem to have slipped since the company's foundation in April 2017. It had indicated that certification of the aircraft would be complete by the end of 2019, which clearly cannot be achieved without a full-scale prototype being ready to start flight tests. The original timeline had indicated that MOBi-One would be in production by 2021. As of February 2020, ASX was indicating that it could take until February 2021 to achieve a first flight with a full-scale testbed vehicle. 

Co-founder (and former NASA scientist) Dr Anita Sengupta told FutureFlight that it has purposely based the program in Detroit in order to capitalise on cost savings it says can be achieved by using off-the-shelf hardware and production techniques from the local automotive industry. It believes the cost of materials for each aircraft will be less than $500,000, resulting in a sales price of no more than $1 million. She also acknowledged that ASX is reconsidering whether to use counter-rotating propellers since these may generate excessive noise. In her view, public acceptance of eVTOL aircraft and regulatory issues are the biggest challenges for companies entering the sector, but mainly in the sense of needing to de-risk programs to reassure investors.

The company's claim in May 2019 that it plans to deliver 2,500 aircraft by 2025 does not seem at all credible, even if the anticipated type certification process goes smoothly. ASX maintains that the type certification process will be relatively straightforward due to its fixed-wing design, which makes it similar to existing short takeoff and landing aircraft. That may be a valid point, but, as of February 2020, the company seemed seriously under-resourced to meet its ambitions. 

By late January 2021, it became clear that design changes initiated during the course of 2020 were quite extensive. The need to rethink the architecture, combined with disruption from the Covid pandemic, pushed back planned fund-raising efforts by at least 12 months. In early February, founder Jon Rimanelli told FutureFlight that he topped up cash reserves himself to sustain the program. He said that he is in contact with a number of funding sources and, once a major partner has been confirmed, will begin a full-blown funding round.

MOBi-One Models

Sigma Six Specifications

local vtol Lift + Cruise


  • Passenger Capacity
  • Range
    90 mi
  • Cruise Speed
    150 mph
  • Powerplant Type
    multi rotor
  • Power Source
  • Endurance
  • Max Altitude
  • Takeoff Distance
  • Landing Distance
  • Empty Weight
  • Payload Weight
    1,000 lb


  • Length
    30 ft
  • Width
    38 ft
  • Height
    10 ft
  • Wingspan

MOBi-One was the name for a tilt-wing design being developed for a mix of cargo- and passenger-carrying applications. During 2020, Airspace Experience Technologies (ASX) initiated a significant engineering review of the architecture for the aircraft's propulsion systems. In early 2021, the company renamed the product Sigma Six and confirmed that it will now only takeoff and land in vertical mode, with repositioned rotors replacing co-rotating propellers. The program timeline has been extended so that an initial all-electric version should be certified for initial cargo operations in 2024, followed by a passenger version in 2026.

ASX is planning to develop both hybrid and electrically powered versions of the aircraft. The company said the aircraft will be able to be operated autonomously by 2030. The electric version of Sigma Six is projected to have a range of 90 miles, while the hybrid version would fly up to 260 miles.

Key Personnel

Jon Rimanelli
Jon Rimanelli

Chief Executive Officer (CEO)