Editing Pusher configuration (section)

===Advantages===
The drive shaft of a pusher engine is in compression in normal operation,<ref name=Gunston>{{cite book|first= Bill|last= Gunston|title= The Cambridge Aerospace Dictionary|publisher= Cambridge University Press|date= 10 May 2004|page= 480|isbn= 978-0521841405}}</ref> which places less stress on it than being in tension in a tractor configuration. {{Dubious|Driveshaft Stress|date=February 2025}}

==== Practical requirements ====
[[Image:G-LOAM MotorFloater first flight.jpg|thumb|Flexwing microlight with engine and propeller at the pilot's back]]
Placing the cockpit forward of the wing to balance the weight of the engine(s) aft improves visibility for the crew. In military aircraft, front armament could be used more easily on account of the gun not needing to synchronize itself with the propeller, although the risk that spent casings fly into the props at the back somewhat offset this advantage.{{citation needed|date = March 2014}}

Aircraft where the engine is carried by, or very close to, the pilot (such as paramotors, powered parachutes, autogyros, and flexwing trikes) place the engine behind the pilot to minimize the danger to the pilot's arms and legs.{{citation needed|date = March 2014}} These two factors mean that this configuration was widely used for early combat aircraft, and remains popular today among [[ultralight aviation|ultralight aircraft]], [[unmanned aerial vehicle]]s (UAVs), and [[radio-controlled airplane]]s.{{citation needed|date = March 2014}}

==== Aerodynamics ====
A pusher may have a shorter fuselage and hence a reduction in both fuselage wetted area and weight.<ref name= "Aircraft Design">{{cite book |last= Raymer|first= Daniel P.|date= 1989|title= Aircraft Design: A Conceptual Approach|location= Reston, Virginia|publisher= American Institute of Aeronautics & Astronautics|pages= 222–223|isbn= 9781600869112}}</ref>

In contrast to tractor layout, a pusher propeller at the end of the fuselage is stabilizing.<ref>{{Cite book|title=Fluid-Dynamic Lift: Practical Information on Aerodynamic and Hydrodynamic Lift |journal= NASA Sti/Recon Technical Report A |volume= 76 |last= Hoerner |first=Sighard | chapter=XIII Directional characteristics of aeroplanes: IV Influence of Propulsion |page=17|bibcode= 1975STIA...7632167H |year= 1975 }}</ref> A pusher needs less stabilizing vertical tail area<ref name= "ask don">{{cite web |title= Don discusses propeller effects in detail...|first= Don|last= Stackhouse|url= http://www.djaerotech.com/dj_askjd/dj_questions/propeffects.html|access-date= 15 October 2011|url-status= dead|archive-url= https://web.archive.org/web/20111121020132/http://djaerotech.com/dj_askjd/dj_questions/propeffects.html|archive-date= 21 November 2011}}</ref> and hence presents less [[Weathervane effect|weathercock effect]];<ref>{{cite book |last= Roskam|first= Jan|date= 1999|title= Airplane Design Part II: Preliminary Configuration Design and Integration of the Propulsion System|volume= 2|location= Lawrence, Kansas|publisher= Design, Analysis and Research Corporation|page= 132|isbn= 9781884885433}}</ref> at takeoff roll, it is generally less sensitive to crosswind.<ref group="note">Because of less weathercock stability</ref><ref>{{citation |url=http://www.flightglobal.com/pdfarchive/view/1992/1992%20-%201611.html |title=Grob tests highlight exhaust problem |journal= Flight International|date= 24–30 June 1992|page=11 |url-status= dead|archive-url=https://web.archive.org/web/20110520124243/http://www.flightglobal.com/pdfarchive/view/1992/1992%20-%201611.html|archive-date= 20 May 2011 }}</ref><ref>{{cite tech report |first= Philip W.|last= Brown|title= Flight test Results for Several Light, Canard-Configured airplanes|number= |institution= NASA Langley Research Center|date= 1 October 1987|doi= 10.4271/871801|issn= 0148-7191|eissn= 2688-3627|url=https://saemobilus.sae.org/content/871801/|url-access= subscription}}</ref>

When there is no tail within the slipstream, unlike a tractor, there is no rotating propwash around the fuselage inducing a side force to the fin. At takeoff, a canard pusher pilot does not have to apply rudder input to balance this moment.<ref>{{cite book|first= Darrol|last= Stinton|date= 1983|title=The Design of the Aeroplane|chapter= Propeller Effects|pages= 304–307|publisher= Granada Publishing|location= St Albans, Hertfordshire, England|isbn= 9780632018772}}</ref>

Efficiency can be gained by mounting a propeller behind the fuselage, because it re-energizes the [[boundary layer]] developed on the body, and reduces the [[form drag]] by keeping the flow attached to the fuselage. However, it is usually a minor gain compared to the airframe's detrimental effect on propeller efficiency.<ref name= "ask don" />

Wing profile drag may be reduced due to the absence of prop-wash over any section of the wing.{{citation needed|date = March 2014}}

==== Safety ====
{{More citations needed section|date=April 2021}}
The engine is mounted behind the crew and passenger compartments, so fuel oil and coolant leaks will vent behind the aircraft, and any engine fire will be directed behind the aircraft. Similarly, propeller failure is less likely to directly endanger the crew.{{citation needed|date = March 2014}}

A pusher ducted fan system offers a supplementary safety feature attributed to enclosing the rotating fan in the duct, therefore making it an attractive option for various advanced UAV configurations or for small/personal air vehicles or for aircraft models.<ref>{{cite web|last1= Abrego|first1= Anita I.|last2= Bulaga|first2= Robert W.|title= Performance study of a ducted fan system|date= 23 January 2002|publisher= American Helicopter Society International, Inc.|url= http://rotorcraft.arc.nasa.gov/publications/files/Abrego2_AHS02.pdf|url-status= dead|archive-url= https://web.archive.org/web/20111018033811/http://rotorcraft.arc.nasa.gov/publications/files/Abrego2_AHS02.pdf|archive-date= 18 October 2011}}</ref>