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I've been flying Cessna 172 & 182's my whole flying life up to this point. I know that Cirruses (Cirri?) have a "side yoke" and Diamonds, Citabrias and others have control sticks coming up through the seat.

Is this a design difference or are there actual functional differences between airplanes that have control yokes (like Cessna 182's) or sticks (like Diamonds) or side yokes (like Cirrus)?

For example, I realize that with the side yoke offers more legroom perhaps, but are there reasons beyond that - like pull/push force required?

Farhan
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Canuk
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3 Answers3

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There is some link between the type of control and the design maneuverability of the aircraft.

Consider a yoke. Imagine twisting it to bank. You are moving it with a twisting motion of one or both arms and in general, aircraft fitted with such yokes are capable of low to moderate roll rates. Big displacements are uncommon but small, rapid, alternating changes are common. Watch a wide body PF making control movements during a landing with any kind of xwind or turbulence. They are less sensitive and give more visual feedback as to the control positions.

Now consider a stick, central to the pilot flying. This is moved with a movement of the arm, generally only one, and can be rapidly displaced easily. This is normally associated with aircraft with high rates of roll, especially in an aircraft designed to rapidly null out or reverse the roll. It is also physically easier to move a stick than a yoke under high-G as the arm movement gives a longer lever.

A great example of this was the Vulcan which, despite its size, enormous wing area and large fin, was so rollable that it could out-maneuver the interceptors of its day. It has a control column rather than a yoke and the PF would throw it around at altitude as if it were a fighter. This would not be easy to do with a yoke.

I'm a bit long in the tooth and haven't flown fixed wing for many years. I am not familiar with the rationale behind side sticks which are fitted to both low and high performance aircraft. I am guessing they are fitted more for reasons of ergonomics than for performance.

user
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Simon
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    Ergonomics (and cockpit layout) is a huge reason to use sidesticks. They free up the space in front of the pilot a lot, and make the usable space in the instrument panel much larger. – egid Jan 13 '14 at 23:17
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    Great answer! Thanks! I never thought about being able to visually distinguish control movements as a benefit. – Canuk Jan 14 '14 at 18:19
  • @egid: should that not be an answer? – Qantas 94 Heavy Jan 21 '14 at 10:54
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    Side-sticks, being smaller, are less precise. So they are only used in aircraft with augmented controls, i.e. the fine adjustments to stabilize the flight path are done by computer. – Jan Hudec Apr 16 '15 at 05:24
  • This answers a question I've thought about a lot. Thanks! Interestingly, if you look at fighter aircraft (particularly from WW2) I believe they all had sticks EXCEPT the twin engined P38. I always wondered about that one. – Ben May 08 '17 at 12:32
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    @JanHudec - the HP-18 sailplane had a sidestick controller. No augmentation of flight controls there! – quiet flyer Aug 26 '19 at 20:35
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I'm posting only to confirm a detail mentioned in Simon's excellent answer, since I've flown all three of the aircraft mentioned in the question (Cirrus, Cessna, Diamond), which he hasn't.

The bit about side yokes, which he mentions he isn't familiar with, is completely correct. To reiterate:

Control type ordered by ease of control input

  1. Center stick (easiest)
  2. Side stick / side yoke
  3. Standard (center) yoke (least easy)
Community
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Steve V.
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    Similar to the usual request for "define efficient", you should define what "easy" means in this context. – Steve Jan 04 '16 at 20:44
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I think you will not find side yokes (side sticks) on older aircraft that have purely mechanical connections to the control surfaces. Sometimes they require both pilot and copilot to shove on the controls to get the desired result. Look at how robust the controls are on a DC-3 for example.

Other than the force required, it is merely a design issue. Potato, Potatoe.

Skip Miller
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    The newer airplanes that he mentions (Cirrus) are also "purely mechanical connections to the control surfaces", so I don't see what the age of the airplane has to do with it. – Lnafziger Jan 13 '14 at 21:23
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    I don't see what force required has got to do with it. With powered flying controls and FBW, very large control forces can be generated and countered with little force on the yoke or stick. Often, these forces have to be clamped and damped to prevent the pilot from tearing bits of the aircraft - think about fin losses following rapid rudder reversals. – Simon Jan 13 '14 at 22:19
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    The Cessna 400 has sidesticks, and uses fully mechanical pushrod linkages. – egid Jan 13 '14 at 23:16
  • Modern airliners use sidesticks.. – Dan Jan 15 '14 at 11:59
  • @Dan: depends on what you call "modern", there are quite a few aircraft out there certified recently with yokes. – Qantas 94 Heavy Jan 21 '14 at 10:53
  • @Qantas94Heavy I didn't mean all airliners, but I meant to further disprove the given answer – Dan Jan 21 '14 at 12:17
  • @Dan: the answer states that older aircraft don't use sidesticks, which your comment doesn't disprove... ;) – Qantas 94 Heavy Jan 21 '14 at 12:33
  • @Dan AFAIK, airliners with sidesticks are all fly-by-wire; at the very least, zero modern airliners have purely mechanical connections to control surfaces (they all use hydraulics as the primary control mechanism). – cpast May 09 '15 at 00:00
  • @Simon "purely mechanical connections to control surfaces" -- FBW is not that, nor are hydraulics. – cpast May 09 '15 at 00:02
  • @SkipMiller - the HP-18 sailplane had a sidestick controller. No augmentation of flight controls there! Purely mechanical conections. Also, it certainly qualifies as "older". – quiet flyer Aug 26 '19 at 20:37