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Old Farang
5th May 2021, 02:48 PM
A bit of a long read, but an insight into why helicopters are unique:
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On a dark night, a pilot begins an unnecessary fight with the helicopter’s autopilot, and loses

The Merlin’s apprentice | Flight Safety Australia (https://www.flightsafetyaustralia.com/2021/05/the-merlins-apprentice/)

Merlin helicopterThe Merlin helicopter was built to replace the venerable Sea King in the anti-submarine warfare role for the Royal Navy. The Merlin was specifically designed to hover over water at night in dark conditions.

To achieve this role and reduce pilot workload, the manufacturer equipped the helicopter with an automatic flight control system (AFCS). This allowed stability augmentation, attitude hold, automated hover and transition modes.

The Royal Canadian Air Force operated the Merlin as the CH-149 Cormorant. In 2006, one of these helicopters, call sign Tusker 914, was conducting a routine night winch training sortie to a ship.

The crew lost control and the helicopter crashed into the ocean. The cockpit structure broke away from the fuselage and the pilots managed to escape. Unfortunately, three of the seven crew died as they could not escape from the rear cabin which was underwater.

Tins
9th May 2021, 12:02 PM
A bit of a long read, but an insight into why helicopters are unique:
.................................................. .................................................. .................................
On a dark night, a pilot begins an unnecessary fight with the helicopter’s autopilot, and loses

The Merlin’s apprentice | Flight Safety Australia (https://www.flightsafetyaustralia.com/2021/05/the-merlins-apprentice/)

Merlin helicopter

The Merlin helicopter was built to replace the venerable Sea King in the anti-submarine warfare role for the Royal Navy. The Merlin was specifically designed to hover over water at night in dark conditions.

To achieve this role and reduce pilot workload, the manufacturer equipped the helicopter with an automatic flight control system (AFCS). This allowed stability augmentation, attitude hold, automated hover and transition modes.

The Royal Canadian Air Force operated the Merlin as the CH-149 Cormorant. In 2006, one of these helicopters, call sign Tusker 914, was conducting a routine night winch training sortie to a ship.

The crew lost control and the helicopter crashed into the ocean. The cockpit structure broke away from the fuselage and the pilots managed to escape. Unfortunately, three of the seven crew died as they could not escape from the rear cabin which was underwater.





I saw Fantasia when I was about 8. That scene with Mickey and the brooms was one of the scariest things ever, and I still remember how it made me feel nearly 60 years later. A good analogy of a cascade of small events leading to disaster. In Michael Crichton's book, Airframe, he discusses the serious results of an airliner porpoising, with the pilot fighting the aircraft, when all he needed to do was let go of the column and let the computer do its job. Not a chopper, I know, but the principle is similar.

JDNSW
9th May 2021, 04:50 PM
My sole experience in actually controlling a helicopter was one occasion when I was traveling in a Bell 47 that had dual controls fitted. As he knew I was a fixed wing pilot, the pilot offered me a go at flying it en route. In my view, the nearest comparison I can make of it is that it is a bit like walking down a road balancing a vertical broom on the palm of your open hand.

BradC
10th May 2021, 11:49 PM
My sole experience in actually controlling a helicopter was one occasion when I was traveling in a Bell 47 that had dual controls fitted. As he knew I was a fixed wing pilot, the pilot offered me a go at flying it en route. In my view, the nearest comparison I can make of it is that it is a bit like walking down a road balancing a vertical broom on the palm of your open hand.

David Gunson does a nice bit on piloting a chopper. "You stir the stick around until you get the helicopter to do what it is you want it to do, then you remember where that was. Next time you want it do do *that*, you put it *there*.".

A few years ago now I had a beer with the first UK Navy pilot to loop (or flop as he called it) a chopper over. That bloke must have had big diamond balls.

It's all magic to me.

ramblingboy42
11th May 2021, 02:32 PM
I was a Raeme Framie for a few years on Kiowas.

When I was setting up a rotor for flight , we would fit interrupters on the mast , wired to a hand held strobe , fit reflectors on the tips of the rotor blades and aim the strobe at them.

I preferred to use 2 x 3's opposing each other giving an 8 in perfect flight. .... which was rare because the rotor flopped and flapped , teeter tottered, one blade led, one blade lagged and the strobe picture changed every time the pilot applied power, applied collective, touched the cyclic or the anti torque and all 4 things would happen at the same time.

We used this to try to make a smooth ship and applied the same thing to tail rotor to remove vibration from foot pedals.

Quite a complex system to follow to make adjustments to all flight controls and surfaces , fly , observe in differing flight envelopes , note , land , make adjustments fly again and hope for improvement and go through the whole cycle again until it was good enough.

I sometimes asked the hangar artificer if we could send any of the boggy pilots up in the ship with an instructor while it was wired up.

To learn all about the disc in theory of flight rotary wing is one thing but to see it actually happening with the strobe was another , it was like a new toy to them.

Fourgearsticks
12th May 2021, 09:12 AM
Flying choppers is one of those things that's blown out of proportion. I took a TIF in a 47 many years ago, could hover/taxi and transition ok first up. Being very current stick time helped, also an idea how things work as well I'm sure. Really how hard can it be? They let girls fly them [tonguewink]