Empennage


thumb|350px|Various_empennage_arrangements:
1. Horizontal stabilizers on top of single vertical stabilizer
2.Ruddervators
3.Horizontal stabilizers placed midway up vertical stabilizer
4. Double fins connected to fuselage by horizontal stabilizer 5. Double fins and horizontal stabilizers attached to fuselage 6. Double fins attached to engine pods, connected by the horizontal stabilizer.
Empennage [ émpənij ] is an aviation term used to describe the tail portion of an aircraft. ("Empennage", "tail", and "tail assembly" may be interchangeably used.) The empennage gives stability to the aircraft and controls the flight dynamics: pitch and yaw. In simple terms the empennage may be compared to the feathers of an arrow, colloquially; "Tail Feathers"

Structurally, the empennage consists of the entire tail assembly, including the fin, tailplane and the part of the fuselage to which these are attached. On an airliner this would be everything behind the rear pressure bulkhead.

The front, usually fixed section of the tailplane is called the horizontal stabilizer and is used to balance and share lifting loads of the mainplane dependent on centre of gravity considerations by limiting oscillations in pitch. The rear section is called the elevator and is usually hinged to the horizontal stabilizer. The elevator is a movable airfoil that controls changes in pitch, the up-and-down motion of the aircraft's nose.

On some aircraft, the horizontal stabilizer and elevator are combined into one movable unit called the stabilator or sometimes "flying tail" (see Anderson, John D., "Introduction to Flight", 5th ed, p 517).In all cases some arrangement is made for the provision of trim to allow minor adjustment of airflow over the control surface and to unload the pilot from the need to maintain constant pressure on the elevator control. The trim may take the form of trim tabs on the rear of the elevators which act to force the elevator in the desired direction, or the stabilizer may be hinged at its trailing edge, forward of the elevator and adjustably jacked a few degrees in incidence either up or down. Early aircraft had a spring in the control circuit which provided an adjustable preload in the desired direction.

The vertical tail structure, or fin, also has a fixed front section called the vertical stabilizer, used to restrict side-to-side motion of the aircraft (yawing). The rear section of the vertical fin is the rudder, a movable airfoil that is used to turn the aircraft in combination with the ailerons.

Occasionally the horizontal stabilizer may carry more than one fin and rudder (Avro Lancaster, Lockheed Constellation) or the stabilizer and fin may be combined into a "V" shaped structure (Ruddervators) with each of the angled airfoils performing both functions (Beechcraft Bonanza 35, Fouga Magister). Frequently the horizontal stabilizer is mounted atop the fin (Boeing 727, Piper Tomahawk)Additional fin area may be added to aircraft fitted with floats (seaplanes) usually beneath the horizontal stabilizer (ventral fin) and sometimes at the stabilizer extremities.

Multi-engined aircraft and some light aircraft also include trim tabs on the rudder when asymmetric forces would impose unusual loads on the pilot's rudder controls.

See also

* Fuselage
* Trijet


Wikimedia Foundation. 2010.

Look at other dictionaries:

  • empennage — [ ɑ̃penaʒ ] n. m. • 1832; de empenner 1 ♦ Action, manière d empenner (les flèches). 2 ♦ (1907) Surfaces placées (comme une empenne) à l arrière des ailes ou de la queue d un avion, d une fusée, d un dirigeable, et destinées à lui donner de la… …   Encyclopédie Universelle

  • empennage — [em′pə nij΄, em pen′ij΄; em΄pə näzh′, äm΄pə näzh′] n. [Fr < OFr empenner, to feather an arrow < em , in + penne, a feather: see PEN] the tail assembly of an airplane, consisting of vertical and horizontal stabilizers, and including the fin …   English World dictionary

  • Empennage —  Pour l’article homophone, voir empannage. Article principal : Configuration générale d un aéronef. Empennage d une fléchette. Originellement, les flèches et fléchettes étaient stabilis …   Wikipédia en Français

  • Empennage en V — Article principal : Morphologie d un aéronef. Fouga Magister (1952) L empennage en V d un avion est un empennage où la gouverne de profondeur et la dérive de direction sont remplacées par deux surfaces en forme de V quand on regarde l… …   Wikipédia en Français

  • empennage — noun Etymology: French, feathers of an arrow, empennage, from empenner to feather an arrow, from em 1en + penne feather, from Middle French more at pen Date: 1909 the tail assembly of an airplane …   New Collegiate Dictionary

  • empennage — The rear portion, or complete tail unit, of an airplane. The empennage stabilizes the airplane in flight and causes it to rotate about its vertical and lateral axes …   Aviation dictionary

  • empennage — /ahm peuh nahzh , em /; Fr. /ahonn pe nannzh /, n., pl. empennages / nah zhiz/; Fr. / nannzh /. the rear part of an airplane or airship, usually comprising the stabilizer, elevator, vertical fin, and rudder. [1905 10; < F: lit., feathering, equiv …   Universalium

  • empennage — noun a) The tail assembly of an aircraft. b) The feathers of an arrow or the tail fins of a bomb or rocket used to stabilize the longitudinal axis of the projectile …   Wiktionary

  • empennage — em·pen·nage || ɪm penɪdÊ’ n. tail of an airplane (or other aircraft) …   English contemporary dictionary

  • empennage — [ɛm pɛnɪdʒ] noun Aeronautics an arrangement of stabilizing surfaces at the tail of an aircraft. Origin early 20th cent.: from Fr., from empenner to feather an arrow , from em in + penne a feather …   English new terms dictionary


Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”

We are using cookies for the best presentation of our site. Continuing to use this site, you agree with this.