User:BilCat/Advancing Blade Concept

From Wikipedia, the free encyclopedia
Sikorsky S-69 (XH-59)
Sikorsky X2
Sikorsky–Boeing SB-1 Defiant

The Advancing Blade Concept system consisted of two rigid, contra-rotating rotors (30 inches apart)[1] which made use of the aerodynamic lift of the advancing blades. At high speeds, the retreating blades were offloaded, as most of the load was supported by the advancing blades of both rotors and the penalty due to stall of the retreating blade was thus eliminated.[2][3] This system did not require a wing to be fitted for high speeds and to improve maneuverability,[4] and also eliminated the need for an anti-torque rotor at the tail.[5] Forward thrust was provided by two turbojets, which allowed the main rotor to only be required to provide lift. It was found to have good hover stability against crosswind and tailwind. With jets installed, it lacked power to hover out of ground effect and used short take-off and landing for safety reasons.[4]


References[edit]

Notes[edit]

  1. ^ Kocivar, Ben. "Turbofan-powered flying carpet" page 68, Popular Science, September 1982. Accessed: September 2014.
  2. ^ Chandler, Jay. "Advanced rotor designs break conventional helicopter speed restrictions (page 1) Archived July 18, 2013, at the Wayback Machine " Page 2 Archived July 18, 2013, at the Wayback Machine Page 3 Archived July 18, 2013, at the Wayback Machine. ProPilotMag, September 2012. Accessed: 10 May 2014. Archive 1 Archive 2
  3. ^ Jackson, Dave. "Coaxial - Sikorsky ~ S-69 (XH-59) ABC Archived November 6, 2014, at the Wayback Machine" Unicopter, 9 March 2012. Retrieved: 22 May 2015. Archived on 6 November 2014.
  4. ^ a b J. Rudell et al. Advancing Blade Concept (ABC) Technology Demonstrator report: USAAVRADCOM-tr-81-D-5, United States Army Research Laboratory, April 1981. Size: 11 MB. Accessed: 10 March 2012.
  5. ^ Apostolo, G. "Sikorsky S-69". The Illustrated Encyclopedia of Helicopters. Bonanza Books, 1984. ISBN 0-517-43935-2.

Bibliography[edit]

External links[edit]

Category:Aircraft configurations