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Choppers always give me the heebie jeebies. Too many things can go wrong. Tail rotor fails, main rotor fails, engine fails...all potentially disasterous. There is no redundant main rotor or tail rotor.
 

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... But at least airplane pilots don't have to worry about retreating blade stall, like helo pilots do (I fly both).
I did some research into this for Fairchild Hiller ... We had a gizmo called the reverse velocity rotor that swapped angle of attack on the retreating blade so that it provided lift from the windstream that was out running the retreating blade ... if you thought the blade in the video was busy, you should have seen this thing in action ... :wow:

Yeah .. it shook itself apart. :upeyes:

That's why the only fast helicopters you're gonna see will have coaxial counter-rotating blades.
 
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Now we need to slap a gopro with a suction cup on the rotor end...
 

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I used to watch guys load aluminum into the 1,000 ton Cyril Bath stretch press in Grumman's Plant 3 stretch area to form rotor blades for Sikorski helicopters, similar to the machine pictured below. Standing in the pit below the machine and looking up at it's arms held horizontal by hydraulics - was quite humbling. Each huge multi-hinged arm all covered in grippers, metal hydraulic lines and flexible hoses reminded me somewhat of the exterior surfaces of a Galactic Empire Star Destoyer from the Star Wars saga. Its h-u-g-e center hydraulic piston (I believe it was 24" or better in diameter) was said to reach down 60' below the pit floor...'amazing machinery.

 

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I was doing a test of the transmission mounting lugs in the FH-1100.
fh-1100.jpeg


Two hefty lugs hold the transmission in the helicopter ... (Or as I prefer to look at it, hold the rest of the helicopter way up in the middle of the air) ... :wow:

We had a problem with stress corrosion causing cracking, and of course, cracks in the lugs holding up your helicopter are ... baaaad ! .. :supergrin:

I was running test rigs to try out a number of solutions ...

Seems I had to take a trip on the company helicopter, (important parts or somesuch) :wow:
I mentioned the status of my 'Jesus lug' work to the company helo pilot ...

He said "Hell, he wasn't worried" ... If they crack, the copter starts shaking first, so you have some warning" .... :alex:
 

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I used to watch guys load aluminum into the 1,000 ton Cyril Bath stretch press in Grumman's Plant 3 stretch area to form rotor blades for Sikorski helicopters, similar to the machine pictured below. Standing in the pit below the machine and looking up at it's arms held horizontal by hydraulics - was quite humbling. Each huge multi-hinged arm all covered in grippers, metal hydraulic lines and flexible hoses reminded me somewhat of the exterior surfaces of a Galactic Empire Star Destoyer from the Star Wars saga. Its h-u-g-e center hydraulic piston (I believe it was 24" or better in diameter) was said to reach down 60' below the pit floor...'amazing machinery.

Well, now we know why helicopter parts are so expensive ... :wow:
 

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That seems like only 259-275 rpm. Is that right?
Probably close

For you helicopter guys, what are those two flappy things. They looked connected. Some sort of counterweight?
They’re weights. Usually we just call them the balls.

exist only to pinch your fingers or bonk your on the head.
 

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I did some research into this for Fairchild Hiller ... We had a gizmo called the reverse velocity rotor that swapped angle of attack on the retreating blade so that it provided lift from the windstream that was out running the retreating blade ... if you thought the blade in the video was busy, you should have seen this thing in action ... :wow:

Yeah .. it shook itself apart. :upeyes:

That's why the only fast helicopters you're gonna see will have coaxial counter-rotating blades.

The Lynx would beg to differ.
 

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The Lynx would beg to differ.
250 .. pretty respectable for conventional layout ..

But not pushing 300 ...

upload_2020-9-25_10-40-52.jpeg


Eurocopter X3 – 293 mph; 473 km/h; 255 knots
The Eurocopter X3 tops the list as the world's fastest helicopter to-date, narrowly beating the Sikorsky X2's unofficial record on 7 June, 2013. The experimental high speed helicopter was designed by Eurocopter (now Airbus Helicopters).
 
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250 .. pretty respectable for conventional layout ..

But not pushing 300 ...

View attachment 837018

Eurocopter X3 – 293 mph; 473 km/h; 255 knots
The Eurocopter X3 tops the list as the world's fastest helicopter to-date, narrowly beating the Sikorsky X2's unofficial record on 7 June, 2013. The experimental high speed helicopter was designed by Eurocopter (now Airbus Helicopters).

I’m just saying there are other fast designs that don’t rely on counter axial counter rotating rotors.

The Bell invictus is another. Or the speed hawk.
 

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I’m just saying there are other fast designs that don’t rely on counter axial counter rotating rotors.

The Bell invictus is another. Or the speed hawk.
Noted ... but at some point (appears to be 250) retreating blade stall limits one main rotor aircraft.
 

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Just hope that Jesus nut doesn't come loose.
And there are so many of them!
I love flying in hellicopters, but you are always just one missed maintenance item away from a crash.
 

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It's called a Jesus nut because it takes an act of God to get it off. If He is otherwise occupied a Power-Dyn will work
I guess I had interpreted it differently. I figured that was what everyone was yelling after the rotor come off and you were flinging towards earth like a bar dart.
 

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I was doing a test of the transmission mounting lugs in the FH-1100.
View attachment 836990

Two hefty lugs hold the transmission in the helicopter ... (Or as I prefer to look at it, hold the rest of the helicopter way up in the middle of the air) ... :wow:

We had a problem with stress corrosion causing cracking, and of course, cracks in the lugs holding up your helicopter are ... baaaad ! .. :supergrin:

I was running test rigs to try out a number of solutions ...

Seems I had to take a trip on the company helicopter, (important parts or somesuch) :wow:
I mentioned the status of my 'Jesus lug' work to the company helo pilot ...

He said "Hell, he wasn't worried" ... If they crack, the copter starts shaking first, so you have some warning" .... :alex:


Not wrong though.

I won’t name the unit to protect the guilty. But I worked with a -60 once that would develop a terrible shake and shudder as you passed through ETL and moved into hovering flight. Turns out the mounting lugs for the transmission were cracking and the transmission was moving just slightly in the airframe as that happened........
 

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I've always like the bit about the difference between fixed-wing pilots and helicopter pilots - it's something like this:

Airplane pilots are generally cheery, upbeat, friendly optimists. Their aircraft wants to fly, even soar gracefully and joyously. If the engine dies, they simply continue to glide, and have lots of time to set up a workable landing.

Helicopter pilots are generally cynical, cranky, grumpy ****ers, who know that Murphy is their co-pilot, and they're flying a machine that's only inches from flying apart when things are going well. If they lose power, they're taking a barely-controlled plummet to the ground, and if they're very very lucky, they'll have one brief chance to bring the aircraft in without making a fresh crater.
 

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Some emergencies can be pretty funny, if you live through them.

Shortly after I graduated from the Army Helicopter Flight School, 1964, Mineral Wells Texas as a Warrant Officer, I was flying a Maryland National Guard Hiller OH23B Helicopter.

After about a 1:15 hour solo flight I was hovering, about 3-4 feet high, across the ramp to the fuel pump.

All the sudden it became very quiet. It's not like in the movies, where the engine misses a few times, then finally quits.
In real life it goes from the very loud engine, to quiet in an instant.

In the next instant I thought,
"Damned it's quiet"---
then,
"The the GD engine quit on me",
then,
"I better do something".

But by now all the many hundreds of practice hovering autorotations/forced landings I had done in flight school, paid off and my body landed the helicopter, with a picture perfect hovering autorotation, while my mind was still trying to catch up.

BTW.
The the problem was two part.
For an unknown reason the engine decided to suddenly use too much fuel-----
at the same time the fuel gauge decided to read too high.
So even though the flight time was well within limits, I actually ran out of fuel early.

Of course the "powers that be" tried to blame me for not topping off the fuel tank, or flying too long.

But when they test flew the helicopter, they saw it was, in fact, using too much fuel and the fuel gauge was reading too high.
 
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