US COAST GUARD PHOTO
US and international endurance records. Te timing of Vought-Sikorsky’s threatened closure proved
fortuitous. Impending war in Europe had increased US interest in all aviation. In June 1938, the Dorsey-Logan law called for the War Department to invest $2 million in research, development, purchase, and testing of rotary-wing and other aircraft. Next came a 1940 US Army competition for an aircraft capable of vertical flight and hovering. Te Platt-LePage Aircraft Company won with its XR-1
transverse-rotor design, considered more capable than the bid proposed by Vought-Sikorsky based on the VS-300. But Platt-LePage experienced testing delays. So the army awarded Dorsey-Logan funds to Vought-Sikorsky to develop the aircraft that became the R-4. Purchased by the US Army Air Forces, Navy, and Coast
Guard and by the Royal Air Force and Royal Navy, the two- seat R-4 became the first large-scale, mass-produced helicopter.
In this August 1944
photo, Igor Sikorsky gets a ride in an HNS-1 (the
designation for an R-4 in US Coast
Guard service) by Cmdr. Frank A.
Erickson. The Coast
Guard pilot had flown the first helicopter lifesaving mission earlier that year,
rushing blood plasma to sailors injured
during the sinking of the USS Turner off the New York coast.
Similar Challenges Today’s eVTOL and advanced air mobility (AAM) sector “is a thriving market with many start-ups that vie to certify and produce new and innovative aircraft this decade,” says Sergio Cecutta, a partner at SMG Consulting, which specializes in aerospace, defense, and automotive technology. Several analysts predict this fledgling industry could be a $1 trillion market by 2050. But just like Sikorsky and the VS-300, there are still some
details to work out. “You may have an aircraft with six lifting rotors, three or
four tilting rotors, and a pusher rotor,” says Jia Xu, Honeywell chief technology officer and senior director of engineering for advanced air mobility. “Tere’s not a great way for the pilot to directly control those rotors or some easy way to blend them together mechanically.” eVTOL will need systems that can “allocate control power across all of your actuators and all your rotors” in an optimized fashion.
46 ROTOR DECEMBER 2022
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68
