When in summer is the first flight of the Long-EZ?
Our Long-EZ (we renamed it Long-ESA for “Electric Speed & Altitude” referring to the world record attempts we will make on (i) fastest manned electric airplane, and (ii) highest altitude manned electric airplane) is scheduled for taxi and static thrust tests the first week of July, with first flight later in July, 2012 depending on the results of the initial taxi and ground performance tests. We expect first flight in July to be from Mojave Air and Space Port (http://mojaveairport.com/) California, which has a 12,500 foot runway and is also the home of Burt Rutan’s former company, Scaled Composites. This all-electric plane will also serve as our flying testbed for our UAV battery pack tethering and docking technology as well as our Jettison & Balance System (“JBS”) battery pack shuttling technology and software development, which is where we have a number of battery packs in a pod below the plane, and as each is depleted, it is jettisoned from the pod and lands at a ground-based collection station via GPS guided parachute – this technique basically doubles the range of an electric airplane through continuous weight reduction as packs are depleted and dropped. The Long-ESA will help us rapidly develop these critical pieces to long-range flight.
What made you decide to embark on this project?
From 2010-2011 my team of aerospace engineers developed, built and raced the world’s fastest electric motorcycle that reached speeds over 200mph. We did everything we could with it, inventing a new Kinetic Energy Recovery System (“KERS”), refining our EV powertrain control software, filing patents, racing against gas powered superbikes and beating them, setting world records at the Pikes Peak International Hill Climb and the Bonneville Salt Flats, so we recently retired it and donated it to the Petersen Automotive Museum, Los Angeles. From there, the next logical question was how can we best deploy the knowledge and technology we developed on that EV program to something bigger and better. After retiring the superbike in September, 2011, I spent several months boating around Southern California and during that brainstorming period, I had the idea to attempt the historic Charles Lindbergh transatlantic flight in an all-electric airplane that we would create (See our 5/22/12 Press Release). Based on the constraints I want to impose on the flight, we quickly determined it would be technically impossible without a big and disruptive innovation. I see this kind of impossible/nearly impossible challenge as a way to push technology forward and usher in a new era of environmentally responsible flight, plus it keeps me motivated, young at heart, and always learning! The Long-ESA is our first plane and is a flying testbed for our tethering and docking technology as well as a platform for attempting the world records, but otherwise plays a supporting role to our big plans for the all-electric Lindbergh flight. That program uses a >100’ wingspan all carbon custom airframe that we are designing in–house and under consultation with some very well respected aviation industry pioneers who are generously lending a hand.
What stage are you at currently with the project?
Our electric Lindbergh plane is in development as is our routing and battery management software, which is almost as important as the airframe. We are developing our own routing optimization software, based on NASA’s OTIS Trajectory Optimization Software (http://otis.grc.nasa.gov/index.html) that has been used from Apollo Space Flight missions all the way up to the present. We have optimized a number of scenarios, each dependant on certain levels of battery performance. For example, we have a scenario of how we can make a successful transatlantic crossing using batteries of 600 wh/kg, 430 wh/kg, 300 wh/kg and 140 wh/kg, the latter being readily available today in the power output range that we need.
I understand you will be flying the plane yourself – what experience do you have of piloting planes?
I have always wanted to be a pilot, but have been waiting for a period in my life where I could fly every day and dedicate myself to becoming a proficient and responsible pilot. I currently fly 6 days a week out of Orange County Airport (SNA) and I have experience flying in Long-EZs as well. As I build up my flight hours, we also have the ability to tap into a group of very experienced test pilots who have contacted us to express interest in flying our electric Long-ESA, including aviation legends Dick Rutan and Mike Melville.
How is the development of the Burt Rutan designed Long-EZ progressing?
Development of the Long-ESA is proceeding at a very rapid pace and the plane will fly under all electric power in July, 2012.
Why don’t you just land and change your batteries rather than employing an unmanned aerial vehicle?
In order for electric airplanes to succeed, they need to overcome a lot of disadvantages relative to internal combustion aircraft, namely convenience, cost, range, speed, and efficiency. We want the recharging process to be transparent to the people flying the planes enabled with our technology, whether it be military applications, cargo and mail delivery, or civilian transportation. In order for electric technology to have any chance to displace internal combustion aircraft, we have to minimize the downsides and maximize the upsides of efficiency, quietness, and pollution advantages of electric power. Since we are in essence limited to using propellers, our average speed is already slower than a jet, and compounding that disadvantage with numerous landings and take-offs, which are not efficient, only hinders the acceptance of electric planes by the industry. Many new technologies fail because people do not like being inconvenienced – asking society to accept flight times twice as long as today’s, with multiple landings and take-offs, will not be a strategy for success!
Certification authorities are notoriously very picky. How can you convince certification authorities it is safe for an external aircraft to dock and tether with the LREA?
Great question! Our first order of business is developing and perfecting the docking and tethering technology and demonstrating it with our Long-ESA. We are setting out in an entrepreneurial venture to smash through the barriers that are preventing long-range flight from becoming a near-term reality. Eventually, we or our development partners will have to face the aviation authorities from around the world, but we are not starting out with bureaucratic hurdles foremost in our minds. We will rejoice when we arrive at the bureaucracy stage however, because it means we have been successful in accomplishing a very difficult technology development process and now need to commercialize it. In the near term, we have arrangements in place with certain airports here in California to allow us to conduct such R&D on their property. We are even in discussions with several airport authorities about becoming a participant in the FAA UAS Test Site Program (http://www.faa.gov/news/press_releases/news_story.cfm?newsId=13393) so that we can provide our input into the future regulations that will govern the safe operation of UAVs in United States airspace.
Is there an example of any aircraft with that procedure in place?
Of course mid-air refuelling is quite common by military operators around the world using hard tethers (extendable booms) and soft tethers (extendable fuel hose) from the fuel tanker aircraft. My favourite is wingwalking refueller Wesley May, who on November 12, 1921, climbed from a Lincoln Standard to a Curtiss JN-4 airplane with a can of fuel strapped to his back to refuel an airplane – the first example that motivates us! Some info on aerial refuelling: http://www.centennialofflight.gov/essay/Evolution_of_Technology/refueling/Tech22.htm
Regarding the transatlantic test, what route are you considering taking? How fast will the aircraft be going as it must have to be pretty fast to be always two hours from land?
There is no requirement to always be two hours from land. In our proposal to the U.S. Department of Energy, we proposed a 24-hour flight with UAV docking events every 90 minutes with a 15 minute changeover period, but for the Lindbergh flight, we will be using a completely new plane and UAV strategy. The speed is set by our own constraint that we have to equal or exceed the average speed of Charles Lindbergh (108 mph average), in order to make the flight meaningful from a technology advancement standpoint (See the constraints in our 5/22/12 Press Release). We have developed a number of scenarios to make a successful transatlantic flight along the Charles Lindbergh route, and we are continuing to refine our model and technology. The strategy we use for the flight in 2014 will undoubtedly be different from what we are proposing and copying you on today, but this helps get people thinking outside the box and in a disruptive manner. We have many other scenarios with more or fewer UAVs and some that depend on better battery energy densities being available, but the important fact is that we currently believe that the flight is currently possible using today’s lithium-ion batteries using our approach with UAVs, such as the 5 UAV scenario attached.
I can see from the Wired article that your long-term vision would involve recharging stations at sea?
For the Lindbergh flight, we are not currently planning to launch or recover any of the 5 UAVs from the ocean, although that may change as we optimize our plan and improve our technology. The Wired.com article shows our vision for the future of transatlantic electric flight routes where platforms are in place to enable long-range electric flights with legitimate payloads.
How are battery packs jettisoned and how are they recovered?
There are three scenarios that we are building, so there are three answers:
Long-ESA is being built with a battery pod attached underneath the fuselage that contains our patent-pending battery pack jettison and rebalance technology. This is a series of lithium-ion packs, each at 450 volts DC, that are individually used to power the aircraft and when depleted, each one is jettisoned out of the pod on a GPS-guided parachute to our recovery and recharge zone on the ground for reuse.
For the Department of Energy ARPA-E proposal, we are building a small manned electric aircraft and two UAV battery pods as part of a contract to demonstrate a 24-hour, non-stop, all-electric flight. This is the scenario outlined in the DoE proposal I recently sent you. The two UAV battery packs are alternately docked to the continuously flying Long Range Electric Aircraft (LREA) – while one is docked, the other is recharged on the ground.
For the Charles Lindbergh flight, we currently plan to use 5 UAV battery packs strategically launched from points shown in the above and attached diagram. Our logistics team must deliver the UAV to each launch site, launch it at the appropriate time, and recover all of the depleted UAV battery packs for shipment back to the USA after our flight.
What is the weight of the battery when you make a changeover to the aircraft?
There are three scenarios that we are building, so there are three answers:
Long-ESA is being constructed in two configurations: 1) the battery pack payload is around 850 lbs total, and for our top speed and high altitude record attempts, we will be using one large parallel pack since the FAI does not allow jettisoning for official world record attempts. 2) for developing our jettison and rebalance technology, the packs we will be using in the Long-ESA will be less than the full voltage of 450 volts, so that we can use more packs to collect maximum data (because each 450 volt pack weighs about 230 lbs, so being limited to 850 lbs total battery weight only allows 3~4 packs to be on the plane) and we want to test scenarios using up to 10 packs, so we will build packs less than 450 volts for testing. But when we use the full 450 volt packs, each pack we drop weighs 230 lbs.
For the Department of Energy ARPA-E proposal, each UAV battery pack weighs approximately 2,000 lbs.
For the Charles Lindbergh flight, the weight is different for each of the 5 UAV battery packs and is not finalized.
What is the payload this prototype aircraft is able to sustain (I’m assuming it is one person – ie, you – but just checking)?
Of course for the first aircraft we are building to perfect our technology, we have one pilot and use all remaining payload for battery packs. This scenario will change as we develop aircraft suitable for different missions and payload. It is always possible to carry more payload by making more frequent jettison and/or re-docking operations during flight.
The text of your press release says it will “enable an entirely new market of long-range, heavy payload, electric flight that would otherwise be impossible to achieve with incremental battery improvements alone.” – how could this technology work for planes able to take bigger payloads such as commercial airlines carrying, say, 100 people. Is it possible?
We believe our approach is scalable, even up to the air transport category, but so far we have not assigned resources on our team to study this far ahead – we are focused on developing and perfecting the technology on a small scale first.
Taking the commercial idea further, wouldn’t jettisoning many batteries on a commercial aircraft carrying 100 people mean parachutes landing empty/used batteries is not feasible (if you think about how many flights take place on any given day around the world and the weight of the batteries, which could be several tonnes to transition and dock)? And is it even commercially viable from a cost standpoint to fly several tonnes of batteries every two hours to dozens of aircraft in a commercial world? Is it finally less expensive than using fuel?
For this scale, we would not propose our parachute approach, for large scale operations, you must drop and re-dock the flying UAV battery packs during flight. There is no reason a large flying UAV battery pack cannot fly up to and be tethered to a large aircraft carrying passengers, freight or military equipment and when the UAV is depleted, it drops away and glides to a landing at a predetermined recovery and recharge location. On the topic of expense, none of this is less expensive than using fuel! Fuel is still incredibly cheap for the amount of energy it is able to store. In the short term, electric airplanes are feasible for specific missions but not as a direct replacement for all fossil fuel burning aircraft. When quiet operations are required, or when the military demands a low heat signature for stealthy operation, or for areas with severe noise restrictions, or for training aircraft doing many landings and take-offs close to an airport, missions like this the electric plane makes sense. One day if society runs low on fossil fuels or when fuel becomes significantly more expensive, only then can you make a direct cost comparison with electric aircraft. This is why virtually all electric vehicles are being subsidized to some extent by someone.
Following on from the last question – does your long term vision for commercial flights powered by electric batteries also rely on the future development of batteries?
The whole premise of our technology is that we are working to provide long-range electric flight now, in the near term, even if no improvements in batteries were forthcoming. We don’t want to wait for batteries to enable long range flight, and we don’t think we have to. In the area of lithium-ion polymer pouch cells suitable for electric vehicle applications, we honestly have not seen much is any improvement in wh/kg in the past 3 years or so – from 2009 to today. Of course improvements are coming, and when they do, you will still need our technology, only you can reduce the number of UAV docking operations for each particular mission. We don’t see any scenario in the foreseeable future where battery technology achieves anything close to fossil fuel energy density parity that is available for purchase and suitable for electric vehicles performing the same missions as gasoline vehicles. This is why we are confident that we are on the right path, and leading the push to build battery-agnostic long-range aircraft right now.
What does the Unmanned Aerial Vehicle (UAV) look like? There are various configurations – mostly a cylindrical pod containing batteries that also has wings! There are several in the image in the Wired article docked to our LREA. The DoE UAVs will be based more on a modified glider airframe, so they will all look different depending on the program.
On your team there are “Byron Young, Robert Ussery, and John Kolaczynski, who all came from the A160 Hummingbird VTOL Unmanned UAV Helicopter program, which successfully transitioned from DARPA funding to a commercial product of The Boeing Company” – can you tell me a bit more about the UAV Helicopter program, how it worked and how it supports the Flight of the Century mission? Also our Chief Engineer Ben Tigner came from the A160 program. This was an unmanned helicopter developed by Frontier Systems and sold to the Boeing Company seen here: http://www.boeing.com/bds/phantom_works/hummingbird.html Our engineers worked on this program as employees of either Frontier Systems or Boeing, or both. Our company Flight of the Century had no role in the A160, but we have the engineers who were successful and are experienced from that exciting program.