Editing Grumman F-14 Tomcat (section)

===Variable-geometry wings and aerodynamic design===
[[File:Grumman F-14 Tomcat SDASM.jpg|thumb|F-14 Tomcat with wings in asymmetric sweep during testing for this possible in-flight malfunction]]

The F-14's wing sweep can be varied between 20° and 68° in flight,<ref name="Dorr p.50.">Dorr 1991, p. 50.</ref> and can be automatically controlled by its [[F-14 CADC|Central Air Data Computer]] (CADC), which maintains wing sweep at the optimum [[lift-to-drag ratio]] as the [[Mach number]] varies; pilots can manually override the system if desired.<ref name="baugher2"/> When parked, the wings can be "overswept" to 75° to overlap the horizontal stabilizers to save deck space aboard carriers. In an emergency, the F-14 can land with the wings fully swept to 68°,<ref name="baugher2"/> although this presents a significant safety hazard due to greatly increased stall speed. Such an aircraft would typically be diverted from an aircraft carrier to a land base if an incident did occur. The F-14 has flown safely with an asymmetrical wing-sweep during testing, and was deemed able to land aboard a carrier if needed in an emergency.<ref>[http://www.f-14association.com/tales/the-story-of-f-14a-aircraft-no-3-buno-157982.html "F-14A, Aircraft No. 3, BuNo. 157982"]. {{Webarchive|url=https://web.archive.org/web/20160311072159/http://www.f-14association.com/tales/the-story-of-f-14a-aircraft-no-3-buno-157982.html |date=11 March 2016}}. F-14 Association. Retrieved: 10 March 2016.</ref>

The wing pivot points are significantly spaced far apart. This has two benefits. The first is that weaponry can be fitted on a pylon on the fixed wing glove, liberating the wings from having swiveling pylons fitted, a feature which had proven to add significant drag on the F-111B.<ref name="mc_f14designevolution"/> Since less of the total lifting area is variable, the center of lift moves less as the wings move, reducing trim drag at high speed.<ref name="mc_f14designevolution"/> When the wing is swept back, its [[thickness-to-chord ratio]] decreases, which allows the aircraft to satisfy the Mach 2.4 top speed required by the U.S. Navy.<ref name="mc_f14designevolution"/> The body of the aircraft contributes significantly to overall lift and so the Tomcat possesses a lower wing loading than its wing area would suggest. When carrying four Phoenix missiles or other heavy stores between the engines this advantage is lost and maneuverability is reduced in those configurations.<ref name="mc_f14designevolution"/>

[[File:Hp scan0021.jpg|thumb|Rear view of the F-14 showing the area between the engine nacelles. |alt=Rear view of stationary aircraft]]
[[Aileron]]s are not fitted, with [[Flight dynamics (aircraft)|roll control]] being provided by wing-mounted [[Spoiler (aeronautics)|spoilers]] at low speed (which are disabled if the sweep angle exceeds 57°), and by differential operation of the all-moving [[Elevon|tailerons]] at high speed.<ref name="baugher2"/> Full-span [[Leading edge slats|slats]] and [[Flap (aircraft)|flaps]] are used to increase lift both for landing and combat, with slats being set at 17° for landing and 7° for combat, while flaps are set at 35° for landing and 10° for combat.<ref name="baugher2"/> An air bag fills up the space occupied by the swept-back wing when the wing is in the forward position and a flexible fairing on top of the wing smooths out the shape transition between the fuselage and top wing area.<ref name="mc_f14designevolution"/> The twin tail layout helps in maneuvers at high angle of attack (AoA) while reducing the height of the aircraft to fit within the limited roof clearance of [[hangar]]s aboard [[aircraft carrier]]s.<ref name="baugher2"/>

The wings have a two-spar structure with integral fuel tanks. Around 25% of the structure is made of [[titanium]], including the wing box, wing pivots, and upper and lower wing skins;<ref name="baugher2">Baugher, Joe (13 February 2000). [http://www.joebaugher.com/navy_fighters/f14_2.html "Grumman F-14A Tomcat"]. {{Webarchive|url=https://web.archive.org/web/20101124022031/http://joebaugher.com/navy_fighters/f14_2.html |date=24 November 2010}} ''Joe Baugher's Encyclopedia of American Military Aircraft''. Retrieved 6 May 2010.</ref> this is a light, rigid, and strong material. [[Electron beam welding]] was used in the construction of the titanium parts. The F-14 was designed for maneuver loads of 7.5&nbsp;g, but this was usually limited to 6.5&nbsp;g in the fleet to extend the aircraft's service life.<ref name="mc_f14designevolution"/>

Two triangular shaped retractable surfaces, called glove vanes, were originally mounted in the forward part of the wing glove, and could be automatically extended by the flight control system at high Mach numbers. They were used to generate additional [[lift (force)|lift]] ahead of the aircraft's [[center of gravity]], thus helping to compensate for [[mach tuck]] at supersonic speeds. Automatically deployed at above Mach 1.4, they allowed the F-14 to pull 7.5 g at Mach 2 and could be manually extended with wings swept full aft. They were later disabled, however, owing to their additional weight and complexity.<ref name="baugher2"/> The [[Air brake (aircraft)|air brakes]] consist of top-and-bottom extendable surfaces at the rearmost portion of the fuselage, between the engine nacelles. The bottom surface is split into left and right halves; the [[tailhook]] hangs between the two-halves, an arrangement sometimes called the "castor tail".<ref name="Sgarlato_p40-46">Sgarlato 1988, pp. 40–46.</ref>