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Question from a mere spotter

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Question from a mere spotter

Old 24th Jun 2020, 20:36
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Question from a mere spotter

Folks,

This is very much an enthusiasts question, so forgive my ignorance...

Is a tandem rotor (like a Chinook) easier to fly than a more conventional helicopter? My simple mind assumes that the two rotors must effectively cancel the torque rotation tendency, but I'm also telling myself it can't be that simple.

Just curious, so any views from the professionals would be appreciated!
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Old 25th Jun 2020, 04:08
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If there was no SAS and autopilot, a Chinook would want to roll on its side and proceed sideways like a twin-engined aeroplane.

Fancy electrickery makes it behave. And it is not easy to fly any helicopter, so all helicopter pilots are steely-eyed, fabulous bodies, and get all the chicks.
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Old 25th Jun 2020, 05:27
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modest as well
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Old 25th Jun 2020, 06:51
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but too
true
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Old 25th Jun 2020, 07:14
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My simple mind assumes that the two rotors must effectively cancel the torque rotation tendency, but I'm also telling myself it can't be that simple.
It is that simple. Unfortunately there is a tendency for the rear rotor to try and catch up with the front rotor so to make it easy for today's spoilt brats called pilots they have electronic stabilisation.

In days of yore the pilot had to sort it out by himself.
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Old 25th Jun 2020, 07:28
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Originally Posted by Fareastdriver View Post
In days of yore the pilot had to sort it out by himself.
..while keeping the fire stoked and the steam at the correct pressure.
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Old 25th Jun 2020, 10:52
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Two pilots, one for the front rotor and one for the back. Remember the blades have to give way to the left.
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Old 25th Jun 2020, 13:17
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Only in France..................
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Old 25th Jun 2020, 16:50
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Just on the off chance the OP wanted a slightly more serious answer, other than the normal differences of aircraft types, a Chinook cockpit looks just like any other twin-engine helicopter cockpit. The lever on the left adjusts the size of the houses, stick in the middle makes you go in the direction you point it, and the pedals on the floor let you decide if you want to see where you are going or not. Some very clever mechanical control mixing handles the basics of the controls operating as per a standard helicopter, then you start to add auto stability and autopilot functions to make it really clever. You need to look at the V-22 Osprey controls to see how some very smart software handles the transition from hover to forward flight, as is the case with the F-35B, but the idea is to make it as close to standard control layout as possible.
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Old 25th Jun 2020, 17:18
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The pilot of a Chinook thinks hes flying a smooth helicopter. In fact hes strapped onto a concrete block, which is connected to the airframe by springs and tends to continue in a nice straight line, while the airframe bounces around all over the place behind him.
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Old 25th Jun 2020, 20:18
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Originally Posted by Ascend Charlie View Post
If there was no SAS and autopilot, a Chinook would want to roll on its side and proceed sideways like a twin-engined aeroplane.

Fancy electrickery makes it behave. And it is not easy to fly any helicopter, so all helicopter pilots are steely-eyed, fabulous bodies, and get all the chicks.
I liked this answer! :-)

But why the tendency to roll?
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Old 25th Jun 2020, 20:19
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Originally Posted by Two's in View Post
Just on the off chance the OP wanted a slightly more serious answer, other than the normal differences of aircraft types, a Chinook cockpit looks just like any other twin-engine helicopter cockpit. The lever on the left adjusts the size of the houses, stick in the middle makes you go in the direction you point it, and the pedals on the floor let you decide if you want to see where you are going or not. Some very clever mechanical control mixing handles the basics of the controls operating as per a standard helicopter, then you start to add auto stability and autopilot functions to make it really clever. You need to look at the V-22 Osprey controls to see how some very smart software handles the transition from hover to forward flight, as is the case with the F-35B, but the idea is to make it as close to standard control layout as possible.
...and this one too...thanks to all for your insights!
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Old 25th Jun 2020, 20:28
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At least a conventional helo has some longitudinal stability in the cruise due to the weathercocking effect of surfaces on the tailboom. The Chinook of course has no such luxury, the nose only points in any given direction in any flight regime because mechanical forces entice it to. This can come as something of a surprise to the pilot who is expecting it to want to point in the direction of travel....

What seriously impressed me upon graduating to SAS off flight was the machine's ability, even propensity to fly pointing in any direction at all regardless of direction of travel with equal happiness. Thus it would quite readily try to swap ends on an ILS or decide to thrunge along sideways if you let it - it simply didn't seem to mind! Not that the results of allowing it to do so were to be reccomended. Limitations, though very generous by conventional helo staandards could easily be eceeded.

A favourite sim game was transition into the hover on the touchdown markings and fly a departure tracking up the ILS in rearwards flight at 60Kts, stabilise to the hover at 1500ft and return down the ILS pointing (!) forwards.
It was possible....
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Old 26th Jun 2020, 01:26
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I am so glad the OP appears to have realised that you guys are all bonkers.
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Old 26th Jun 2020, 02:59
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That is actually very interesting.
I didn't realise that if it weren't for the SAS, you steely eyed cyclic wranglers would have trouble getting a Wokka to point forwards.
Son has an Army chopper driver Officer Selection Board coming up soon.
Have told him that if he gets it - there's only one machine to fly - and it ain't got a conventional tail rotor!
Not that the green machine will let him decide - one ends up flying what one is told I gather.
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Old 26th Jun 2020, 05:45
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If he wants to fly a Chinook in the UK, hell have to join the RAF, not the Army.
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Old 26th Jun 2020, 07:33
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Originally Posted by meleagertoo View Post

A favourite sim game was transition into the hover on the touchdown markings and fly a departure tracking up the ILS in rearwards flight at 60Kts, stabilise to the hover at 1500ft and return down the ILS pointing (!) forwards.
It was possible....
Sim game? We would back up the GCA at Culdrose just to see how long it would take the controller to realise what was wrong with his screen
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Old 26th Jun 2020, 07:50
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Helicopters fly because they are ugly and the earth repels them.
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Old 26th Jun 2020, 12:39
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It has to be better to stop and then land opposed the other way round.
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Old 26th Jun 2020, 14:34
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Two’s In, I like the you’re explanation.

Do you instruct? As a plank driver, with you instructing, I’m sure I could learn fairly quickly!

Simples - T18
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