Vertical lift engine concepts (Comprehensive list? Future promise?)

Questions to discuss

Are any systems missing (and do you have better examples of each)?

What are the major design trade-offs in these systems?

What systems have development potential




The list

-- Dedicated lift jets

-- Rotated aircraft / rotated fuselage / tail-sitter

-- Vectored thrust (jet engine)

-- Propulsive wing (distributed)

-- Tilt-prop (upward or downwards)

-- Tilt rotor (or ducted fan) / tilt-wing / tilt-engine (jet)

-- Decoupled prop (e.g. X-2 and X-3 demonstrators)

-- Distributed Electric Fans
http://www.secretprojects.co.uk/forum/index.php/topic,13981.msg155169.html#msg155169
http://www.aero-news.net/index.cfm?do=main.textpost&id=d9d17a0e-441f-43f8-8515-8f9814c03230

-- Gas driven buried (or retractable) lift fans

-- Shaft driven buried (or retractable) lift fans

-- Rotary wing / stop-rotor
http://www.secretprojects.co.uk/forum/index.php/topic,431.0.html

-- Stopped-Stowed (Retractable) rotor / Trail rotor

-- Disc-rotor

-- Thrust-augmented wing
http://www.secretprojects.co.uk/forum/index.php/topic,2081.0.html

-- Pulse-Ejector-Thrust-Augmentor (PETA)
http://www.secretprojects.co.uk/forum/index.php/topic,224.msg131131.html#msg131131

-- Cyclogyros aircraft
http://www.secretprojects.co.uk/forum/index.php/topic,2837.0.html

-- Fanwings
http://www.secretprojects.co.uk/forum/index.php/topic,4458.msg54957.html#msg54957

-- Deflected slipstream (or extreme upper surface blowing)
www.secretprojects.co.uk/forum/index.php/topic,18461.msg177450.html#msg177450

-- Ion powered
http://www.secretprojects.co.uk/forum/index.php/topic,14662.msg146667.html#msg146667

-- Volume / Lift balloons / Retractable Balloons
http://www.secretprojects.co.uk/forum/index.php/topic,17348.0.html

-- Rockets (or rocket-parachute combinations)
http://www.secretprojects.co.uk/forum/index.php/topic,17250.msg21805.html#msg21805