286:(FAA) has more recently decided that these instruments are obsolete in today's flight environment. Advisory Circular No. 91-75, issued on 6/25/2003, states the following: "...in today's air traffic control system, there is little need for precisely measured standard rate turns or timed turns based on standard rate." The Advisory Circular further states: "...the FAA believes, and all other commenters apparently agree...the rate-of-turn indicator is no longer as useful as an instrument which gives both horizontal and vertical attitude information." Thus one can now legally replace a Turn-and-Slip or Turn Coordinator instrument with a second attitude indicator, preferably driven by a system different from the primary flight display. So if the aircraft primary display is vacuum powered, the second attitude indicator should be electric, and vice-versa. This gives more flight information than the rate-of-turn indicator and gives a safety measure of redundancy of systems. The slip indicator (the "ball") is still required. The slip indicator may be mounted separately in the panel, or, some attitude indicators now have a slip indicator included in the display.
246:
209:
120:
184:, which is recognized as the "ball in a tube". An inclinometer contains a ball sealed inside a curved glass tube, which also contains a liquid to act as a damping medium. The original form of the indicator is in effect a spirit level with the tube curved in the opposite direction and a bubble standing in for the ball. In some early aircraft the indicator was merely a
151:, a torque force is applied to the gyro around the vertical axis, due to aircraft yaw, which causes gyro precession around the roll axis. The gyro spins on an axis that is 90 degrees relative to the direction of the applied yaw torque force. The gyro and gimbal rotate (around the roll axis) with limited freedom against a calibrated spring.
38:
253:
Slipping and skidding within a turn is sometimes referred to as a sloppy turn, due to the perceptive discomfort it can cause to the pilot and passengers. When the aircraft is in a balanced turn (ball is centered), passengers experience gravity directly in line with their seat (force perpendicular to
220:
The turn coordinator (TC) is a further development of the turn and slip indicator (T/S) with the major difference being the display and the axis upon which the gimbal is mounted. The display is that of a miniature airplane as seen from behind. This looks similar to that of an attitude indicator. "NO
162:
The display contains hash marks for the pilot's reference during a turn. When the needle is lined up with a hash mark, the aircraft is performing a "standard rate turn" which is defined as three degrees per second, known in some countries as "rate one". This translates to two minutes per 360 degrees
192:
for damping. The ball gives an indication of whether the aircraft is slipping, skidding or in coordinated flight. The ball's movement is caused by the force of gravity and the aircraft's centripetal acceleration. When the ball is centered in the middle of the tube, the aircraft is said to be in
224:
In contrast to the T/S, the TC's gimbal is pitched up 30 degrees from the transverse axis. This causes the instrument to respond to roll as well as yaw. This allows the instrument to display a change more quickly as it will react to the change in roll before the aircraft has even begun to yaw.
163:
of turn (a complete circle). Indicators are marked as to their sensitivity, with "2 min turn" for those whose hash marks correspond to a standard rate or two-minute turn, and "4 min turn" for those, used in faster aircraft, that show a half standard rate or four-minute turn. The supersonic
110:
The turn and slip indicator can be referred to as the turn and bank indicator, although the instrument does not respond directly to bank angle. Neither does the turn coordinator, but it does respond to roll rate, which enables it to respond more quickly to the start of a turn.
232:
has failed. This is called "partial panel" operations. It can be unnecessarily difficult or even impossible if the pilot does not understand that the instrument is showing roll rates as well as turn rates. The usefulness is also impaired if the internal
172:, using these figures allows a pilot to perform timed turns in order to conform with the required air traffic patterns. For a change of heading of 90 degrees, a turn lasting 30 seconds would be required to perform a standard rate or "rate one" turn.
266:. These slips are performed by applying opposite inputs of the aileron and rudder controls. A forward slip allows a pilot to quickly drop altitude without gaining unnecessary speed, while a sideslip is one method utilized to perform a
167:
jet aircraft and many military jets are examples of aircraft that use 4 min. turn indicators. The hash marks are sometimes called "dog houses", because of their distinct shape on various makes of turn indicators. Under
257:
While aircraft slipping and skidding are often undesired in a usual turn that maintains altitude, slipping of the aircraft can be used for practical purposes. Intentionally putting an aircraft into a slip is used as a
85:
that at rest displays the angle of the aircraft's transverse axis with respect to horizontal, and in motion displays this angle as modified by the acceleration of the aircraft. The most commonly used units are
154:
The torque force against the spring reaches an equilibrium and the angle that the gimbal and gyro become positioned is directly connected to the display needle, thereby indicating the rate of turn. In the
193:
coordinated flight. If the ball is on the inside (wing down side) of a turn, the aircraft is slipping. And finally, when the ball is on the outside (wing up side) of the turn, the aircraft is skidding.
237:
is worn out. In the latter case, the instrument is underdamped and in turbulence will indicate large full-scale deflections to the left and right, all of which are actually roll rate responses.
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404:
144:. The gyro's rotational axis is in-line with the lateral (pitch) axis of the aircraft, while the gimbal has limited freedom around the longitudinal (roll) axis of the aircraft.
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PITCH INFORMATION" is usually written on the instrument to avoid confusion regarding the aircraft's pitch, which can be obtained from the artificial horizon instrument.
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in one device. One indicates the rate of turn, or the rate of change in the aircraft's heading; the other part indicates whether the aircraft is in
668:
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seat). With a well balanced turn, passengers may not even realize the aircraft is turning unless they are viewing objects outside the aircraft.
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Although the Turn and Slip
Indicator (and later the Turn Coordinator) was felt to be a necessary and required instrument for flight under
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Operation demonstration of a Turn & slip indicator. The indicator cover is removed and gyro is displayed as it operates.
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Although this instrument reacts to changes in the aircraft's roll, it does not display the roll attitude.
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Skidding. The corrective action is to press the "left" pedal adequately.
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The turn coordinator may be used as a performance instrument when the
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911:
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A simple alternative to the balance indicator used on gliders is a
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Graphic of a turn and slip indicator and a turn coordinator
458:"MS28041 H SHEET INDICATOR TURN SLIP 28V DC 1-7/8 INCH"
212:
Image showing the face of a turn coordinator during a
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Coordinated flight indication is obtained by using an
41:
Illustration of the face of a turn-and-slip indicator
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323:Advisory Circular AC 91-75, Issued June 25th, 2003
81:of the turn. The slip indicator is actually an
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512:
8:
737:
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519:
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497:
314:Pilot's Handbook of Aeronautical Knowledge
136:instrument that works on the principle of
65:(TC) variant are essentially two aircraft
30:"T/S" redirects here. For other uses, see
344:
427:: CS1 maint: archived copy as title (
420:
382:: CS1 maint: archived copy as title (
375:
7:
689:Integrated standby instrument system
25:
479:. Pitman Boots LTD. p. 243.
664:Air data inertial reference unit
464:from the original on 2015-11-20.
442:"How Aircraft Instruments Work."
410:from the original on 2015-09-24
332:Federal Aviation Administration
318:Federal Aviation Administration
284:Federal Aviation Administration
1647:In-flight entertainment system
1344:Horizontal situation indicator
628:Horizontal situation indicator
587:Horizontal situation indicator
1:
312:Advisory Circular AC 61-23C,
1627:Environmental control system
140:. The gyro is mounted in a
1704:
1304:Course deviation indicator
995:Electro-hydraulic actuator
633:Inertial navigation system
623:Course deviation indicator
328:Instrument Flying Handbook
29:
27:Aircraft flight instrument
1535:Conventional landing gear
334:(IFH), (Update 25 Nov 05)
1319:Flight management system
132:The turn indicator is a
1622:Emergency oxygen system
1384:Turn and slip indicator
1179:Leading-edge droop flap
1149:Drag-reducing aerospike
1124:Adaptive compliant wing
1119:Active Aeroelastic Wing
592:Turn and slip indicator
280:instrument flight rules
216:coordinated right turn.
170:instrument flight rules
59:turn and bank indicator
51:turn and slip indicator
1662:Passenger service unit
1463:Self-sealing fuel tank
1359:Multi-function display
694:Primary flight display
475:A. C. Kermode (2006).
447:, March 1944, pp. 117.
301:Primary flight display
250:
241:Practical implications
217:
124:
42:
1642:Ice protection system
1560:Tricycle landing gear
1550:Landing gear extender
767:Aft pressure bulkhead
248:
211:
122:
40:
1688:Aircraft instruments
1607:Auxiliary power unit
1015:Flight control modes
643:Satellite navigation
274:Current Legal Status
1586:Escape crew capsule
1493:War emergency power
1364:Pitot–static system
1209:Variable-sweep wing
917:Vertical stabilizer
477:Mechanics of Flight
32:TS (disambiguation)
1294:Attitude indicator
1274:Airspeed indicator
1269:Aircraft periscope
618:Aircraft periscope
577:Attitude indicator
549:Airspeed indicator
528:Flight instruments
251:
230:attitude indicator
218:
125:
71:coordinated flight
67:flight instruments
43:
1675:
1674:
1602:Aircraft lavatory
1339:Heading indicator
1284:Annunciator panel
1264:Air data computer
1174:Leading-edge cuff
712:
711:
582:Heading indicator
486:978-1-4058-2359-3
268:crosswind landing
16:(Redirected from
1695:
1657:Navigation light
1637:Hydraulic system
1612:Bleed air system
1540:Drogue parachute
1214:Vortex generator
832:Interplane strut
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638:Magnetic compass
597:Turn coordinator
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358:. Archived from
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204:Turn coordinator
157:turn coordinator
147:As the aircraft
63:turn coordinator
21:
18:Turn coordinator
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1667:Ram air turbine
1632:Flight recorder
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1483:Thrust reversal
1407:
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1369:Radar altimeter
1334:Head-up display
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1129:Anti-shock body
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960:Artificial feel
942:Flight controls
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802:Fabric covering
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748:components and
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684:Head-up display
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445:Popular Science
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398:"Archived copy"
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353:"Archived copy"
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320:, Revised 1997.
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296:Flight dynamics
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1574:Escape systems
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657:Related topics
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73:, showing the
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679:Glass cockpit
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629:
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621:
619:
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430:
424:
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399:
393:
390:
385:
379:
365:on 2014-02-11
361:
354:
348:
345:
339:
336:
333:
329:
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281:
273:
271:
269:
265:
261:
255:
247:
240:
238:
236:
231:
226:
222:
215:
214:standard rate
210:
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199:
194:
191:
187:
183:
175:
173:
171:
166:
160:
158:
152:
150:
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135:
127:
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114:
112:
105:
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101:
97:
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89:
84:
80:
76:
72:
68:
64:
60:
56:
52:
48:
39:
33:
19:
1617:Deicing boot
1545:Landing gear
1488:Townend ring
1478:Thrust lever
1453:NACA cowling
1418:Autothrottle
1410:fuel systems
1408:devices and
1383:
1199:Stall strips
1169:Krueger flap
1139:Channel wing
1085:Wing warping
1075:Stick shaker
1070:Stick pusher
990:Dual control
975:Centre stick
842:Leading edge
812:Flying wires
772:Cabane strut
611:Navigational
591:
536:Pitot-static
476:
470:
452:
444:
437:
412:. Retrieved
392:
367:. Retrieved
360:the original
347:
327:
313:
277:
260:forward slip
256:
252:
227:
223:
219:
195:
182:inclinometer
179:
176:Inclinometer
161:
156:
153:
146:
131:
109:
83:inclinometer
62:
58:
54:
50:
44:
1565:Tundra tire
1448:Intake ramp
1379:Transponder
1164:Gurney flap
1105:Aerodynamic
1020:Fly-by-wire
902:Triple tail
94:(deg/s) or
1555:Oleo strut
1443:Inlet cone
1438:Gascolator
1404:Propulsion
1394:Yaw string
1389:Variometer
1245:instrument
1224:Wing fence
1159:Gouge flap
1134:Blown flap
1090:Yaw damper
1065:Stabilator
1050:Side-stick
985:Dive brake
872:Stabilizer
847:Lift strut
837:Jury strut
704:Yaw string
569:Gyroscopic
559:Variometer
414:2015-02-05
369:2014-02-28
307:References
198:yaw string
138:precession
134:gyroscopic
102:(min/tr).
61:) and the
1530:Autobrake
1458:NACA duct
1433:Fuel tank
1423:Drop tank
1406:controls,
1289:Astrodome
1279:Altimeter
1144:Dog-tooth
1109:high-lift
1060:Spoileron
1045:Servo tab
1025:Gust lock
980:Deceleron
965:Autopilot
922:Wing root
907:Twin tail
892:Tailplane
827:Hardpoint
797:Empennage
760:structure
554:Machmeter
544:Altimeter
115:Operation
57:, a.k.a.
1682:Category
1498:Wet wing
1473:Throttle
1219:Vortilon
1080:Trim tab
1010:Flaperon
1000:Elevator
955:Airbrake
927:Wing tip
852:Longeron
822:Fuselage
758:Airframe
746:Aircraft
699:V speeds
462:Archived
423:cite web
405:Archived
378:cite web
290:See also
264:sideslip
186:pendulum
165:Concorde
47:aviation
1508:Landing
1299:Compass
1247:systems
1239:Avionic
1229:Winglet
1112:devices
1055:Spoiler
950:Aileron
932:Wingbox
857:Nacelle
807:Fairing
750:systems
330:, U.S.
316:, U.S.
235:dashpot
190:dashpot
188:with a
96:minutes
88:degrees
1243:flight
1204:Strake
1035:Rudder
1005:Elevon
970:Canard
912:V-tail
887:T-tail
817:Former
777:Canopy
483:
282:, the
262:and a
142:gimbal
92:second
49:, the
1428:FADEC
1314:EICAS
1189:Slats
1030:HOTAS
882:Strut
408:(PDF)
401:(PDF)
363:(PDF)
356:(PDF)
1510:and
1374:TCAS
1354:ISIS
1309:EFIS
1254:ACAS
1241:and
1194:Slot
1154:Flap
1107:and
1095:Yoke
867:Spar
792:Dope
674:EFIS
669:ECAM
648:SIGI
481:ISBN
429:link
384:link
149:yaws
106:Name
100:turn
98:per
90:per
79:skid
75:slip
1349:INS
1329:GPS
1184:LEX
862:Rib
77:or
55:T/S
45:In
1684::
460:.
425:}}
421:{{
403:.
380:}}
376:{{
270:.
738:e
731:t
724:v
520:e
513:t
506:v
489:.
431:)
417:.
386:)
372:.
53:(
34:.
20:)
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