[Jeroen]

I have a quick question about the difference between aircrafts and helicopters.

Aircrafts have the captain sitting in the left seat. Also, if you have a cockpit with two pilot seats which is flown by one pilot, he/she will always sit in the left seat. (e.g. like I always do in the planes I pilot) In some planes the left seat has controls not available to the right seat (e.g. nose steering)

With helicopters it is the other way round, it is all about the right seat? I have flown in the cockpit of various helicopters, as passenger, next to the pilot, always in the left seat.

Why would that be? Is it just coincidence or is there some particular reason?

Jeroen

[V.Narayan]

Originally Posted by Jeroen

I have a quick question about the difference between aircrafts and helicopters.

Aircrafts have the captain sitting in the left seat. Also, if you have a cockpit with two pilot seats which is flown by one pilot, he/she will always sit in the left seat. (e.g. like I always do in the planes I pilot) In some planes the left seat has controls not available to the right seat (e.g. nose steering)

With helicopters it is the other way round, it is all about the right seat? I have flown in the cockpit of various helicopters, as passenger, next to the pilot, always in the left seat.

Unlike fixed wing aircraft as you know helicopters need constant steering and direction on the "cyclic" control stick to stay in the air. Helicopters are designed so that the majority of people's dominant hand can easily rest on the stick at all times. Poor co-pilot.

[Jeroen]

Originally Posted by V.Narayan

Unlike fixed wing aircraft as you know helicopters need constant steering and direction on the "cyclic" control stick to stay in the air. Helicopters are designed so that the majority of people's dominant hand can easily rest on the stick at all times. Poor co-pilot.

Thanks, had not thought of it, makes sense.

Some of the earlier helicopters (e.g. Sikorsky R4) had one central collective in between the pilots. But they would always put the student pilot in the right hand seat.

I have seen a few other thoughts. Most helicopters, due to the way the rotor works have a tendency to tilt slightly to the left. i.e. the left skid would be a little lower than the right unless the pilot compensates.

In small helicopters it helps if a solo pilot sits on the right, in addition to your earlier comments.

I don’t think the dominant hand is something that is given much thought in fixed wing aviation. All pilots throughout their career will move from right to left seat, and vice versa. You get used to it very quickly.

Jeroen (strictly fixed wing pilot!)

[Aviatoraval]

Originally Posted by Jeroen

I have a quick question about the difference between aircraft and helicopters.

Aircraft have the captain sitting in the left seat. Also, if you have a cockpit with two pilot seats which is flown by one pilot, he/she will always sit in the left seat. (e.g. like I always do in the planes I pilot) In some planes, the left seat has controls not available to the right seat (e.g. nose steering)

With helicopters it is the other way round, it is all about the right seat? I have flown in the cockpit of various helicopters, as passenger, next to the pilot, always in the left seat.

Why would that be? Is it just coincidence or is there some particular reason?

Jeroen

As per my knowledge, the Left seat is the Captain seat in Helicopters too. In fact, the right seat is used by Examiners, Instructors, and Copilots who are not qualified for the missions being flown.
(Trained on fixed wing and Rotory both, Strictly Rotory Pilot)

Originally Posted by Jeroen

Thanks, had not thought of it, makes sense.

Some of the earlier helicopters (e.g. Sikorsky R4) had one central collective in between the pilots. But they would always put the student pilot in the right-hand seat.

I have seen a few other thoughts. Most helicopters, due to the way the rotor works have a tendency to tilt slightly to the left. i.e. the left skid would be a little lower than the right unless the pilot compensates.

In small helicopters it helps if a solo pilot sits on the right, in addition to your earlier comments.

I don’t think the dominant hand is something that is given much thought in fixed wing aviation. All pilots throughout their career will move from right to left seat, and vice versa. You get used to it very quickly.

Jeroen (strictly fixed wing pilot!)

That roll which you are talking about is called the Tail rotor roll. If viewed from above, If the rotor rotates clockwise there will be a left roll and if rotor rotate anticlockwise there will be a right roll. And if it's Coaxial or contrarotating rotors there will be no tail rotor roll. Placing a pilot on the left or right has no relation to tail rotor roll.

The dominant hand does not play any role in Helicopters too. In the majority of helicopters, Both sides have the same controls. In fact, in multiple legs, pilots switch seats (Not Mid-Air - That's possible in large fixed wing only)

[Jeroen]

Originally Posted by Aviatoraval

As per my knowledge, the Left seat is the Captain seat in Helicopters too. In fact, the right seat is used by Examiners, Instructors, and Copilots who are not qualified for the missions being flown.
(Trained on fixed wing and Rotory both, Strictly Rotory Pilot)

I am not so sure about this, because I have rarely seen a helicopter flown from the left seat. As I mentioned, my own experience is I always got the left seat.

Many moons ago I took helicopter flying lessons. I flew on two different types, both from the right hand seat.

Originally Posted by Aviatoraval

That roll which you are talking about is called the Tail rotor roll. If viewed from above, If the rotor rotates clockwise there will be a left roll and if rotor rotate anticlockwise there will be a right roll. And if it's Coaxial or contrarotating rotors there will be no tail rotor roll. Placing a pilot on the left or right has no relation to tail rotor roll.

I think it is slight different, although it does start with the rotor. 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.

Originally Posted by Aviatoraval

The dominant hand does not play any role in Helicopters too. In the majority of helicopters, Both sides have the same controls. In fact, in multiple legs, pilots switch seats (Not Mid-Air - That's possible in large fixed wing only)

As I mentioned, you might be right, but my observations and hands on experience shows something different.

It might be that on more modern helicopters with more advanced cyclic adjusted power control, the dominant hand has become a non issues. But google “why are helicopters flown from the right seat” the dominant hand is mentioned in just about all cases and a bit of historical perspective as well.

From the pilotteacher:

https://pilotteacher.com/are-helicop...or-right-seat/

Seems most helicopters are still flown from the right hand side, but some are capable of being flown from both seats. Partly for the reasons we discussed, partly for historical reason.

I don’t know, but I assume that if you have a helicopter with two pilot positions, which can be flown by one pilot, that position is part of the certification? Left or right pilot flying solo affects the centre of gravity and handling. As I mentioned earlier on the Robinson it was simply not allowed to fly from the left seat.

Anybody aware if this is in fact so? I can imagine the effects are larger on small helicopters than on large helicopters though.

Jeroen

[V.Narayan]

Originally Posted by Aviatoraval

As per my knowledge, the Left seat is the Captain seat in Helicopters too. In fact, the right seat is used by Examiners, Instructors, and Copilots who are not qualified for the missions being flown.
(Trained on fixed wing and Rotory both, Strictly Rotory Pilot)

That roll which you are talking about is called the Tail rotor roll. If viewed from above, If the rotor rotates clockwise there will be a left roll and if rotor rotate anticlockwise there will be a right roll. And if it's Coaxial or contrarotating rotors there will be no tail rotor roll. Placing a pilot on the left or right has no relation to tail rotor roll.

The dominant hand does not play any role in Helicopters too. In the majority of helicopters, Both sides have the same controls.

Honoured to have an IAF pilot on this thread. My salute to you for your service to the nation. What you refer to regarding both seats is, I assume, the case with military choppers. But in civilian machines, tradition or need, the captain sits on the right.

[Aviatoraval]

Originally Posted by Jeroen

I think it is slight different, although it does start with the rotor. 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.




I don’t know, but I assume that if you have a helicopter with two pilot positions, which can be flown by one pilot, that position is part of the certification? Left or right pilot flying solo affects the centre of gravity and handling. As I mentioned earlier on the Robinson it was simply not allowed to fly from the left seat.

Anybody aware if this is in fact so? I can imagine the effects are larger on small helicopters than on large helicopters though.

Jeroen

The tail rotor of a helicopter produces a moment to overcome the couple arising from torque reaction which in turn causes a side pull on the pivot point or axis of rotation of the main rotor. This side force produces a movement known as TAIL ROTOR DRIFT and unless corrected would result in the helicopter moving sideways over the ground. Tail rotor drift can be corrected by tilting the rotor disc away from the direction of the drift. And this can be done by mounting of MGB tilted, Rigging of controls or Pilot moving cyclic sideways. This will provide you Tail rotor drift correcting force. The tail rotor drift corrective force being produced by the main rotor, will create a rolling couple with the tail rotor thrust, causing the helicopter to hover one wheel low which is called Tail rotor roll.

Helicopters do have very sensitive CG bandwidth, That may be the reason behind R22 seating arrangement in case of single pilot ops.

Originally Posted by V.Narayan

Honoured to have an IAF pilot on this thread. My salute to you for your service to the nation. What you refer to regarding both seats is, I assume, the case with military choppers. But in civilian machines, tradition or need, the captain sits on the right.

Sir, real honor is to have you on this forum so that we all can gain wisdom. I forgot to mention about the fact that my reply came from my experience of military aviation.

[V.Narayan]

https://www.deccanherald.com/nationa...h-1191286.html

The Indian army aviation Corps is set to order 90 Prachand light attack helicopters and 110 LUH light utility helicopters. Good for us. I only hope the distance from announcing the plan to placing the order to HAL actually delivering on time is short and sweet. The LUH is primarily to replace the ageing Cheetah {Aerospatiale SA316B} and Chetak {Alouette III}. Along with this an order for 40 Helina anti-tank missile launchers {Nag family} and 500 missiles. I assume more orders will follow as these numbers seem low. But then this is public news – reality might be different.

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Ah, a much needed step in the right direction. I think it was a bad look that no orders of note had been made yet for the Prachand despite it being tailor made for a long standing requirement. Obviously still needs putting pen to paper.
Same goes for the LUH, another vital capability.
Not quite as big an order as one would like for either of the two platforms but at least a step in the right direction. Would be good to see them both out and about in the coming years rather than simply air show duty.

[directinjection]

Came across this insightful piece in today's The Tribune. It's written by Air Vice Marshal Manmohan Bahadur (Retd), Former Additional Director General, Centre for Air Power Studies. He raises questions about the safety record of HAL Dhruv and recommends a thorough review of its design, specifically of the ‘collective’ or ‘cyclic’ pitch rods.

https://www.tribuneindia.com/news/co...h-dhruv-487709

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Originally Posted by directinjection

Came across this insightful piece in today's The Tribune. It's written by Air Vice Marshal Manmohan Bahadur (Retd), Former Additional Director General, Centre for Air Power Studies. He raises questions about the safety record of HAL Dhruv and recommends a thorough review of its design, specifically of the ‘collective’ or ‘cyclic’ pitch rods.

https://www.tribuneindia.com/news/co...h-dhruv-487709

This is bringing back memories of the not too distant public, and very acrimonious mud slinging between HAL on one side and (current and former) IN personnel on the other side, wrt the shortcomings or lack thereof (depending on which camp you were in) the navalised Dhruv. Being reminded of the crash history of the Dhruv isn't a strong look when it seems to keep happening (the author says as much, early doors its understandable but it's been in service awhile now). I can't speak to the merits of the postulated cause but I feel like QC improvements at HAL in general seems to be something they should work on to avoid the reactionary accusations after incidents such as these.

A question for those who know, say one of these pitch rods fails, can the crew rely on autorotation of the rotors to bring a helicopter down?

[skanchan95]

Flaws in military’s Dhruv helicopters identified — ‘mix of metallurgical, design issues’

Three of these indigenous Advanced Light Helicopters have crashed since March, forcing military to ground fleet twice. Choppers flying again but parts being changed, it is learnt.

New Delhi: After detailed checks of the grounded fleet, the Indian military has finally identified metallurgical and design flaw in a critical component of the indigenous Advanced Light Helicopter (ALH) — a workhorse of the armed forces — that had caused some of the recent accidents, ThePrint has learnt.

Sources in the defence and security establishment said that the helicopters are being operated again, but the parts are being changed on a priority basis and their flying life has been reduced from what it was earlier.

ThePrint was the first to report in October 2022 that the crash of an armed ALH, also known as the Rudra, in Arunachal Pradesh had occurred after the “collective”, which controls the power to the rotors and back, had broken.

It was found that this part of the helicopter was troublesome since the Court of Inquiry (CoI) into the 2019 crash of an ALH, in which the then Northern Army commander Lt. Gen. Ranbir Singh had a miraculous escape, also revealed the failure of the “collective”.

Following multiple accidents this year, a top government regulatory body, responsible for the certification of military aircraft, is undertaking a full review of the ALHs.

“Yes we have identified. We have sought replacement of the particular part and this is being replaced as we speak. The whole process will take time,” a top source in the defence establishment said, responding to a query on whether they have been able to identify the problem.

Asked whether this was a design flaw or a metallurgical issue, the source said, “It is a mix of both”.

“The good part is that the flaw has been identified and is being taken care of,” a second source added.

While the helicopters, over 300 of which have been manufactured, have logged over 3 lakh flying hours, there have been a series of accidents in the last few years. Three ALHs have crashed since March this year, forcing the military to ground the entire fleet twice for technical checks.

It was found that certain parts are showing higher fatigue than what the time frame is. The sources explained that normally a particular part has a flying life of about 400 hours, then it is serviced or replaced after 400 hours.
However, if the fatigue develops much before that, then the flying life has to be reduced so that necessary replacement or service can be done in time.

Along with the ALHs, the indigenous Light Combat Helicopter (LCH) was also grounded and underwent a full technical check by the armed services. This was because the LCH is also a variant of the ALH and, hence, shares the same parts and technology.

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Originally Posted by skanchan95

Flaws in military’s Dhruv helicopters identified — ‘mix of metallurgical, design issues’

While this is certainly dispiriting news, good that it's been identified. Hopefully the replacement of the defective part is happening on a priority basis. Again, while it's a shame that the MTO will go down considerably now because of the need to be extra cautious with the operational time assigned to these components, better to be safe than sorry. Much easier to replace one brittle part than an entire airframe or more so the personnel inside.

Even I know the collective is a pretty crucial part of rotary wing aviation. That such a critical component was subpar should be a major embarrassment for HAL. It seems really baffling that despite a lot of the QC gripes that come out about various HAL rotary wing platforms, they haven't gone out of their way to show a concerted and serious push to overhaul their internal quality control processes.

[dragracer567]

Originally Posted by skanchan95

Flaws in military’s Dhruv helicopters identified — ‘mix of metallurgical, design issues’

Meanwhile, we had arm-chair experts on Youtube and Twitter who would scorn the groundings of the HAL Dhruv relegating them to some sort of conspiracy by the 'import lobby'!

[skanchan95]

Originally Posted by dragracer567

Meanwhile, we had arm-chair experts on Youtube and Twitter who would scorn the groundings of the HAL Dhruv relegating them to some sort of conspiracy by the 'import lobby'!

Yes, hopefully this will be the end of the Dhruv's troubles. It was disturbing to see the loyalties of decorated aviators questioned by trolls for simply asking the right questions and stating the facts. I suppose all those trolls and arm chair Marshals have gone into hiding today!!! There was a video of the injured pilot of the last Dhruv crash. He seemed very angry lying on the ground in pain and he said take me as it is, seeming refusing to take first aid, probably wanting to send a message to someone higher up or to HAL.