VIDEO: Elroy Air successfully flies Chaparral C1 — the world’s first turbogenerator hVTOL aircraft

Elroy Air’s Chap­ar­ral C1 final­ly took flight ear­li­er this week, as the com­pa­ny com­plet­ed the mile­stone at its test facil­i­ty in Byron, Cal­i­for­nia, on Novem­ber 12th.

The Chap­ar­ral took flight from Byron Air­port, where the Elroy Air Team runs flight test oper­a­tions. Lever­ag­ing both its tur­bo­gen­er­a­tor sys­tem and high-pow­er bat­ter­ies the C1 took off ver­ti­cal­ly, flew for 57 sec­onds, and land­ed suc­cess­ful­ly.

Elroy Air co-founder and CEO Dave Mer­rill, said: “This is an exhil­a­rat­ing day for our team and the indus­try as a whole. In 2017 we had an uncon­ven­tion­al idea to devel­op an autonomous long-range VTOL air­craft that would fill a major capa­bil­i­ty gap for mid­dle-mile express ship­ping, human­i­tar­i­an logis­tics, and mil­i­tary resup­ply.

On Sun­day, our Chap­ar­ral C1 became the first tur­bo­gen­er­a­tor-hybrid elec­tric hVTOL air­craft to take flight. This marks a major moment for the indus­try as hybrid-elec­tric air­craft enable the dual ben­e­fits of run­way-inde­pen­dent safe redun­dant propul­sion, and long-range flight well in excess of bat­tery pow­er alone.

“Our accom­plish­ment puts Elroy Air one step clos­er to deliv­er­ing a trans­for­ma­tive logis­tics capa­bil­i­ty to our cus­tomers and part­ners.”

The C1 is an autonomous hVTOL air­craft, with dis­trib­uted elec­tric propul­sion and a tur­bo­gen­er­a­tor-bat­tery archi­tec­ture. This achieve­ment marks a sig­nif­i­cant step for­ward in Elroy Air’s mis­sion to enable same-day ship­ping to every per­son on the plan­et and agile, low-risk resup­ply for Defense.

To devel­op and bring the world’s first hVTOL air vehi­cle into flight test, the Elroy Air team over­came sub­stan­tial tech­nol­o­gy chal­lenges in elec­tri­cal pow­er man­age­ment and struc­tur­al vibra­tion.

The company’s intel­lec­tu­al prop­er­ty and deep accu­mu­lat­ed tech­ni­cal expe­ri­ence posi­tions Elroy Air at the fore­front of hVTOL air­craft devel­op­ment. Elroy Air’s engi­neer­ing team is led by Zach Lover­ing, an aero­space engi­neer and eVTOL indus­try vet­er­an who con­tributed to mul­ti­ple air­craft devel­op­ment pro­grams at Zee Aero (now Wisk), and sub­se­quent­ly led the pio­neer­ing Vahana eVTOL air­craft pro­gram at Acubed by Air­bus.

Lover­ing added: “This ground­break­ing ini­tial flight of the C1 will be fol­lowed by an ongo­ing enve­lope expan­sion cam­paign in coor­di­na­tion with the US Air Force in which we’ll advance the vehicle’s demon­strat­ed flight capa­bil­i­ties through sub­se­quent modes of air­borne oper­a­tions,” said Elroy Air VP of Engi­neer­ing Zach Lover­ing. “These modes include expand­ed hov­er, sys­tem iden­ti­fi­ca­tion, tran­si­tion, and cruise flight.”

Hybrid-elec­tric air­craft rep­re­sent a crit­i­cal advance­ment in the avi­a­tion indus­try. For ver­ti­cal flight, dis­trib­uted elec­tric propul­sion (DEP) using mul­ti­ple redun­dant rotors enables robust and safe oper­a­tions even in the case of motor fail­ure — a key enabler for auton­o­my.

How­ev­er, today’s bat­tery-elec­tric eVTOL air­craft designed for Air Taxi and car­go oper­a­tions are range-con­strained due to the ener­gy den­si­ty lim­i­ta­tions of avail­able bat­tery cells, and they must be oper­at­ed in loca­tions with sub­stan­tial bat­tery-charg­ing infra­struc­ture. The com­bi­na­tion of DEP and tur­bine-based elec­tri­cal pow­er gen­er­a­tion yields a best-of-both-worlds option first sug­gest­ed by NASA researchers in 2008.

Tur­bo­gen­er­a­tor-hybrid archi­tec­ture address­es the lim­i­ta­tions of all-elec­tric sys­tems by com­bin­ing a gas tur­bine-dri­ven gen­er­a­tor with bat­ter­ies — enabling long-range mis­sions (a “must-have” for logis­tics) with­out requir­ing charg­ing infra­struc­ture, as well as safe redun­dant flight for autonomous oper­a­tions.

Ashish Bagai, advanced rotor­craft expert, said: “The use of hybrid elec­tric pow­er­trains is not triv­ial – bal­anc­ing bat­tery and tur­bo­gen­er­a­tor pow­er out­put to respond to load demand requires pow­er man­age­ment sys­tems that are prop­er­ly gov­erned to facil­i­tate effec­tive and effi­cient flight.

“Such sys­tems for true VTOL and ver­ti­cal flight capa­ble air­craft are more com­plex and demand­ing than for fixed wing sys­tems because of the dis­crep­an­cies in pow­er require­ments in dif­fer­ent flight regimes. This is a major step in the devel­op­ment of hVTOL flight – one that under­scores the poten­tial util­i­ty val­ue of DEP con­cepts. It’s very encour­ag­ing.”

Elroy Air’s Chap­ar­ral is in high demand from a num­ber of lead­ing part­ners in com­mer­cial, human­i­tar­i­an, and defense logis­tics.

Its vehi­cle back­log — reflect­ed in LOIs and MOUs with a grow­ing num­ber of deposit-backed agree­ments — today exceeds $3 bil­lion in future rev­enues. Since start­ing work with AFSOC in 2019, the com­pa­ny now holds three active con­tracts with US Air Force (SBIR Phase II, SBIR Phase III, and TACFI).

The Chaparral’s capa­bil­i­ties address an urgent oper­a­tional need for logis­tics in con­test­ed envi­ron­ments where today’s alter­na­tive is dan­ger­ous resup­ply mis­sions using expen­sive crewed air­craft, a demand reflect­ed by its active part­ner­ships with the Defense com­mu­ni­ty.

Dr. Mark Esper, 27th US Sec­re­tary of Defense and Elroy Air Board Mem­ber, said: “The team at Elroy Air has achieved an excit­ing mile­stone with the first flight of their Chap­ar­ral air­craft. Their work to enable autonomous car­go deliv­ery for the resup­ply of troops in the field will cre­ate a game-chang­ing capa­bil­i­ty for sup­port­ing and sus­tain­ing the Unit­ed States mil­i­tary and allied forces in future cam­paigns.”