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So far as I am aware, in a fixed wing aircraft having side-by-side seating and dual controls but only a single set of instruments, those instruments are always positioned in front of the left seat. Even when an aircraft (such as commercial air transport) is fitted with dual instruments, the left seat is designated as the "pilot-in-command" or "captain's" position. This "left-seat as principal" designation appears to hold true for any fixed wing aircraft from a Cessna 152 to a Boeing 747, in all jurisdictions of manufacture and operation.

For a helicopter, the situation appears to be reversed - the "pilot in command" appears to always occupy the right seat.

Is this true, always, or is it an observational bias? Is this simply convention or is it specified by regulation? What would account for exceptions, if any?

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    $\begingroup$ There are exceptions. The EC 130 has three seats in front: the PIC occupies the left seat and the copilot (if there is one) the middle seat. I don't know the reason for this arrangement. Also, the Ka-26 (an possibly other russian helicopters) has the PIC position on the left seat. As a helicopter pilot flying from the right seat makes sense, because I can keep my right hand on the cyclic all the time and I operate any other equipment with my left hand. $\endgroup$ – Emil Aug 18 '14 at 5:27
  • $\begingroup$ Interesting that this just caught my eye. I just finished watching A Chopper is Born about kit-building a RotorWay Exec 162F. Every shot of that helicopter, from the demo flights at the factory to the test pilot giving the finished kit it's initial shakedown flight, shows the PIC on the left. $\endgroup$ – FreeMan Oct 23 '15 at 16:01
  • $\begingroup$ @Emil When you mentioned the EC-130, were you referring to the C-130 Hercules cargo aircraft? If so, the third seat is the flight engineer's position, and the copilot sits in the right seat. In the Air Force, the flight engineer is not a pilot, and that position's job is to monitor engine functions. $\endgroup$ – Howard Miller Oct 23 '15 at 23:32
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    $\begingroup$ @HowardMiller No, I meant the Eurocopter EC130 (which now it's called Airbus Helicopters H 130) $\endgroup$ – Emil Oct 25 '15 at 4:23
  • $\begingroup$ @Emil Thanks for clearing that up for me. $\endgroup$ – Howard Miller Oct 25 '15 at 6:30
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The reason is both historical and operational.

The first mass produced helicopter was the Sikorsky R-4. It had a single collective located between the two pilot seats, so by necessity, the person on the right would control the cyclic with their right hand, and the person on the left would control the cyclic with their left (because their right is needed on the collective). The cyclic in the R-4 was very difficult to manipulate and required a lot of strength and coordination. Since the vast majority of student helicopter pilots were right handed, they sat in the right seat, allowing them to use their dominant hand on the cyclic. Thus, the first generation of helicopter pilots all sat in the right seat, since they all learned on the R-4 (or the R-6). That's how traditions begin.

The operational applications of sitting in the right seat relate to the inherent instability of a helicopter. A helicopter pilot rarely wants to let go of the cyclic, as it often requires continuous control inputs, especially when hovering. The collective, on the other hand, does not need to be monitored as closely and can be held steady with a friction adjustment, so that hand is occasionally free to manipulate things like radios and other equipment, which are located in the center of the cockpit.

Most helicopters these days have a collective for each seat, located on the left, so the pilot wants to use the hand in the middle of the cockpit to work the radios and things. Hence, they sit on the right side, which places the collective hand in the middle of the cockpit.

You can read a longer article about this: Why do helicopter pilots sit in the right seat?

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  • $\begingroup$ The person on the right would control cyclic (in the middle) with their right? I seem to be missing something. $\endgroup$ – Jan Hudec Aug 17 '14 at 19:32
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    $\begingroup$ @Jan Hudec: The left hand controlled the collective. The collective is always (as far as I know) between the seats. $\endgroup$ – Skip Miller Aug 17 '14 at 20:06
  • $\begingroup$ @SkipMiller: So it's really the same as aircraft that have power in the middle and the outer hand always holds the flight controls. Except controlling aircraft is easier, so noone appears to mind controlling it with left hand (including monsters like A380 which has single-handed controls on the outer, so captain's left, hand). $\endgroup$ – Jan Hudec Aug 17 '14 at 20:11
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    $\begingroup$ Editing my comment above is timed out, so: Comment Continues...or to the left of the seat in aircraft with more than one collective control. Thanks to Ralgha. I have not seen a dual collective helicopter. $\endgroup$ – Skip Miller Aug 17 '14 at 20:15
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    $\begingroup$ @JanHudec the important point you're missing is that the fly by wire joystick on an airbus is electronic and requires no force (not, particularly, precision), whereas the collective on the early helicopters needed a fair bit of strength, plus constant attention and accuracy. The Airbus requires little more effort to fly with the left hand than the right, especially after a little practice (similar to how I'm typing this response with both hands). $\endgroup$ – Jon Story Jan 6 '15 at 12:07
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The thrust from the tail rotor on a counter-clockwise spinning helicopter tends to create a translational shift to the right which is countered by rigging the cyclic neutral position to be slightly left of centre. This results in the left skid "hanging low". So as not to make this skid even lower, it is a practical reason to sit a solo occupant on the right. Even when solo, the left skid still hangs visibly lower. Some light helicopters are prohibited from solo flight in the left seat (e.g. R22) as it would be possible to run out of cyclic authority in some circumstances.

Here is the lateral CG chart for the R-22. As you can see, the right side of the helicopter has a greater lateral CG envelope than the left, which is why the solo pilot always sits on the right.

enter image description here

The opposite is true for clockwise spinning main rotors.

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    $\begingroup$ French helicopters have clockwise spinning main rotors and most of them still have the PIC on the right seat. $\endgroup$ – Emil Aug 18 '14 at 5:28
  • $\begingroup$ @Emil Why the PIC would still sight on the right, I do not know (can you provide an example?) but the skid low tendency would be on the right. $\endgroup$ – Simon Aug 18 '14 at 14:50
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    $\begingroup$ All French-built Eurocopters, except the 130 have the PIC on the right side (including older Aerospatiale Dauphin). Indeed, the skid low tendency is on the right, so I suppose there are more important reasons to keep the PIC on the right side than adjusting the CG position. $\endgroup$ – Emil Aug 18 '14 at 16:38
  • $\begingroup$ @Simon this is a very good answer. many FWers don't realize that helis have a lateral CG. the R22, being so light, is particularly sensitive to lateral CG, as you rightly described, and indeed has a minimum solo pilot weight as well. robinsonheli.com/manuals/r22_poh/r22_poh_2.pdf $\endgroup$ – rbp Jan 4 '15 at 19:04
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    $\begingroup$ (continuation...) its not clear, however, if this is cause or effect, in the sense that rotors go CCW historically and the radios are in the middle, so the CG envelope was designed for a right-seat solo pilot. $\endgroup$ – rbp Jan 4 '15 at 19:10
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Another reason helicopter pilots sit on the right is because the cyclic is held in the right hand, and the collective in the left.

Its safer for the pilot to take his left hand off the collective to operate the radios.

enter image description here

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  • $\begingroup$ Is that a single, common cyclic in the center, instead of separate sticks joined at foot level? $\endgroup$ – FreeMan Oct 23 '15 at 15:32
  • $\begingroup$ its not any different than any other mechanical heli, except this one is an "outie" (visible) versusu an "innie" (invisible, under the floor boards): incolor.inetnebr.com/iceman/data/fltcls2.jpg $\endgroup$ – rbp Oct 23 '15 at 15:40
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In the early years when helicopters were under powered and their rotor systems were simple and basic it made sense for the pilot to sit on the right because the advancing blade, on the right create more lift then the retreating blade on the left since the forward speed of the chopper is added to the rotational speed of the blade. This caused asymmetrical lift and it was partially compensated for by having the pilot sit on that side of the helicopter. When flying The H 13 in Korea with both seats occupied we always placed the litter on the right skids for that reason. Ren

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  • $\begingroup$ Welcome to aviation.SE! $\endgroup$ – Pondlife Aug 8 '17 at 13:57
  • $\begingroup$ Asymmetrical lift would roll the helicopter over, the left skid low flight would be caused by the tail rotor being lower that the main rotor. But that's a minor detail, welcome to the site. $\endgroup$ – Koyovis Aug 8 '17 at 14:13
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In short:

The reason lies in the instability of helicopters.

  1. Contrary to airplanes, helicopters aren't naturally stable. One hand is constantly on the cyclic stick (the main control) to adjust the aircraft attitude. For a right-handed pilot, the delicate and uninterrupted task of maintaining stability is more easily carried out using the right-hand. This implies the left hand has the burden to manipulate all other controls.

  2. With helicopters controllable from a single seat, this was not a problem, the second control in order of importance, the collective lever, was located on the left side of the pilot. This allowed to use the airplane configuration with the pilot on the left side.

  3. The problem appeared with dual-controlled helicopters which were also more complex aircraft: There were many controls between the two seats, so they can be used by both pilots. After a quick experimentation, it was clear the left-hand should be close to these controls.

  4. The main pilot seat was therefore shifted to the right one, and a single collective lever was positioned, with other existing controls, between the seats.


At the beginning: No difference with airplane

First dual seats helicopters were piloted from the left seat, exactly like other aircraft. Focke-Achgelis FA 223:

enter image description here

(Youtube)

Pilot used their left hand for the power lever (collective) and the cyclic stick was under right hand control. Bell HTL-4:

enter image description here

(Source)

Return of experience: Handle cyclic with left hand

Contrary to an airplane, there is no stability on an helicopter, even less at that time. The rotor had to be adjusted continuously to maintain a safe attitude. On the other side, the collective with its rotating ring could be kept in a given position without hand contact.

Pilot right hand being unavailable for something else than the stick, radio buttons manipulation, tank selection and other tasks had to be conducted with the left hand.

However it appeared quickly this was not the best configuration for a single pilot, the left hand having a more limited reach than the right one in the middle of the cockpit.

Dual seat aircraft means also a possibility for dual controls and two pilots, some controls have to be located on a central console, more difficult to reach with the left hand.

Designers were quick to move the collective lever in the middle, meaning a pilot used to control the collective with the left hand would seat in the right seat to continue piloting the same way. One of the first helicopter to use this configuration has been the Sikorsky H-19 (HRS-3).

enter image description here

Sikorsky H-19 (Youtube)

It's visible on the previous image, from an ergonomics standpoint, this configuration allows for the free hand (left) to reach a lot of levers and switches while the other is constantly busy adjusting the cyclic stick to keep the helicopter in a safe attitude.

For left-handed people, the "weak" hand will have to do the latter task, this will be a little less easy. For them, the initial "airplane" configuration was clearly an advantage. With dual-control helicopters, left-handed pilots could sit in the left seat if they preferred, but as for airplanes, the standard (right-handed) arrangement is used.


An additional detail: "Why is the PIC position for helicopters the right seat" -- PIC (pilot in command) is not synonymous to PF (pilot flying). The above details pertain to PF. PIC could seat anywhere as long as they are not flying the aircraft.

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  • $\begingroup$ This cavalry theory might explain why airplanes were 'mounted' from the left side (although to me the naval legacy is more plausible here), but hardly the seat arrangement. Nearly all airplanes of that era (that had more than one seat) had tandem seating rather than side-by-side. $\endgroup$ – Zeus Nov 25 '18 at 23:54

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