Editing VTOL (section)

==Powered lift==
{{Main|Powered lift}}There are number of designs for achieving power lift, and some designs may use more than one. There are many experimental designs that have unique design features to achieve powered lift. [[File:F-35B Lighting II training flights 170203-M-ON157-0436.jpg|thumb|The F-35B uses a ducted fan and also directs (vectors) its rear exhaust downward.]]

===Convertiplane===
{{Main|Convertiplane}}
A convertiplane takes off under rotor lift like a helicopter, then transitions to fixed-wing lift in forward flight. Examples of this include the [[Bell Boeing V-22 Osprey]]

====Tiltrotor====
{{Main|Tiltrotor}}
A tiltrotor or proprotor tilts its propellers or rotors vertically for VTOL and then tilts them forwards for horizontal wing-borne flight, while the main wing remains fixed in place.

====Tilting ducted fan====
Similar to tiltrotor concept, but with [[ducted fan]]s, as can be seen in the [[Bell X-22]].

====Tiltwing====
{{Main|Tiltwing}}
A tiltwing has its propellers or rotors fixed to a conventional wing and tilts the whole assembly to transition between vertical and horizontal flight.

===Tail-sitter===
{{Main|Tail-sitter}}
A tail-sitter sits vertically on its tail for takeoff and landing, then tilts the whole aircraft forward for horizontal flight.

===Vectored thrust===
{{Main|Thrust vectoring}}
Thrust vectoring is a technique used for jet and rocket engines, where the direction of the engine exhaust is varied. In VTOL, the exhaust can be varied between vertical and horizontal thrust.

====Tiltjet====
{{Main|Tiltjet}}
Similar to tiltrotor concept, but with turbojet or turbofan engines instead of ones with propellers.

===Lift jets===
{{Main|Lift jet}}
A lift jet is an auxiliary jet engine used to provide lift for VTOL operation, but may be shut down for normal wing-borne flight. The [[Yak-38]] is the only production aircraft to employ lift jets.

===Lift fans===
{{Main|Lift fan}}
Lift fan is an aircraft configuration in which lifting fans are located in large holes in an otherwise-conventional fixed wing or fuselage. It is used for V/STOL operation.

The aircraft takes off using the fans to provide lift, then transitions to fixed-wing lift in forward flight. Several experimental craft have been flown, but only the [[F-35 Lightning II]] entered into production.

===Lift via Coandă effect===
{{Main|Coandă effect}}
Aircraft in which VTOL is achieved by exploiting the [[Coandă effect]] are capable of redirecting air much like [[thrust vectoring]], but rather than routing airflow through a duct, the airflow is simply routed along an existing surface, which is usually the body of the craft allowing less material and weight.

The [[Avro Canada VZ-9 Avrocar]], or simply the VZ-9, was a Canadian VTOL aircraft developed by [[Avro Canada|Avro Aircraft Ltd.]] which utilizes this phenomenon by blowing air into a central area, then it is directed down over the top surface, which is [[parabola|parabolic]] and resembles a bowed [[flying saucer]]. Due to the Coandă effect, the airflow is attracted to the nearest surface and continues to move along that surface despite the change in the surface's direction away from the airflow. The craft is designed to direct the airflow downward to provide lift.

Jetoptera announced a proposed line of aircraft based on what it called fluidic propulsion that employs the Coandă effect. The company claims an [[Oswald efficiency number]] of 1.45 for its boxwing design. Other claims include increased efficiency, 30% lower weight, reduced complexity, as much as 25 [[A-weighting|dBA]] lower (and atonal) noise, shorter wings, and scalability.<ref>{{Citation|title=Jetoptera's Bladeless Propulsion System|date=February 18, 2021|url=https://www.youtube.com/watch?v=bPZI6XoHi10| archive-url=https://ghostarchive.org/varchive/youtube/20211117/bPZI6XoHi10| archive-date=2021-11-17 | url-status=live|publisher=Electric Aviation|language=en|access-date=2021-04-29}}{{cbignore}}</ref><ref>{{Cite web|last=Blain|first=Loz|date=2021-04-28|title=Jetoptera VTOL aircraft design features "bladeless fans on steroids"|url=https://newatlas.com/aircraft/jetoptera-aircraft-propulsion-system/|url-status=live|access-date=2021-04-30|website=New Atlas|language=en-US |archive-date=2021-04-30 |archive-url=https://web.archive.org/web/20210430104212/https://newatlas.com/aircraft/jetoptera-aircraft-propulsion-system/ }}</ref> Jetoptera says its approach yields thrust augmentation ratios exceeding 2.0 and 50% fuel savings when compared to a [[turbofan]] in static or hovering conditions. Its efflux can be used for Upper Surface Blown architectures to boost the [[Lift Coefficient]] to values exceeding 8.0.