I call BS on that story.
They're doing a lot more than just advancing and retreating, anyone who didn't realize that within the first week of training would have to be pretty dense.
Helicopter Main Rotor Blade in slow-mo
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They're doing a lot more than just advancing and retreating, anyone who didn't realize that within the first week of training would have to be pretty dense.
Maybe it is, after all -- it is relayed through another person. That said, the description of being in a constant state of wind-shear didn't come from the helicopter pilot, that was my take on it (As the blade is advancing, it's akin to being in a headwind, as it retreats, it's similar to being in a tailwind. Constant changes in headwind and tailwind would generally fit the definition of windshear, as I understand it), though it seems my interpretation was wrong. The thing that I considered interesting was the description of camera footage that showed the movement of the blade as it spun. It was described as being something like an angry, flailing snake.
The footage shown here was quite mellow in comparison to that.
Of course.
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You are probably talking about this footage...
Nothing crazy really. They are designed to flex like that.
Then there is this one. A Bo-105...
How about an Mi-8?
Nothing crazy really. They are designed to flex like that.
Then there is this one. A Bo-105...
How about an Mi-8?
I couldn't say, but that does look closer to what was described -- boy that thing flexes a lot. I know it's designed to take that (if it didn't, every flight would end up with the blade braking apart, and a crash ensuing)
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wuzak
Captain
Similar to aircraft wings.
Of course everyone knows that flapping the wings is how planes fly.
Not helicopters though...
They make so much noise that the Earth repels them!
That's why they're inspected very often for cracks.
With the OH6 I was up there at least every day we flew looking for cracks, nicks, etc., on a few eventful days I was up there looking more than once.
More modern helicopters have pressurized blades, when the pressure drops, that's a sign there are cracks in the blades releasing that pressure maybe.
A pressure sensor detects the pressure drop and turns on a warning light, and maybe a audible warning too.
It screams " you're gonna die, you're gonna die, you're gonna die ".
Until you get used to it helicopters do make some weird noises, lucky they're so noisy in normal operation, you don't hear most of the weird stuff.
One of my pilot's form of a joke was all of a sudden coming over the intercom with " what's that noise ?", or what's that smell. ?
He didn't use the second one anymore after I told him, "probably you ".
With the OH6 I was up there at least every day we flew looking for cracks, nicks, etc., on a few eventful days I was up there looking more than once.
More modern helicopters have pressurized blades, when the pressure drops, that's a sign there are cracks in the blades releasing that pressure maybe.
A pressure sensor detects the pressure drop and turns on a warning light, and maybe a audible warning too.
It screams " you're gonna die, you're gonna die, you're gonna die ".
Until you get used to it helicopters do make some weird noises, lucky they're so noisy in normal operation, you don't hear most of the weird stuff.
One of my pilot's form of a joke was all of a sudden coming over the intercom with " what's that noise ?", or what's that smell. ?
He didn't use the second one anymore after I told him, "probably you ".
Yeap, on the UH-60A/L Blackhawk it was called the BIM indicator. It was not digital though. The indicator was installed on the blade, and we would check it before abd after every flight, as well as on most scheduled inspections. If the color on the indicator changed from yellow to red, it meant a drop in pressure. We would then have to inspect the blade for cracks. Usually it was a faulty indicator o-ring.
Helicopters may create a little wind shear as they fly along, but they're not flying in it themselves, they're leaving it behind them.
For the next guy to fly through, and I've done that when around a formation of choppers, it's a little rough.
But not as bad as the turbulence left behind by say, a low flying F-4, or a C-130.
And nothing like the wind shear dished out by mother nature.
For the next guy to fly through, and I've done that when around a formation of choppers, it's a little rough.
But not as bad as the turbulence left behind by say, a low flying F-4, or a C-130.
And nothing like the wind shear dished out by mother nature.
That's wake turbulence. Another reason mother earth repels them....
I can see why the comparison was made with wind shear: the velocity of the airflow is constantly going up and down, which is why the pitch of the blade is constantly changing.
That's turbulence.
Wind shear is when there is a dramatic change in wind speed or direction in a short altitude change.
The problem comes because the aircraft's momentum is related to groundspeed, but it flies by airspeed. So, you can go from an airspeed of say 100kts, with a groundspeed of 80kts with a 20 kt headwind. If that wind changes direction to a 20kt tailwind, your groundspeed remains 80kts, but your airspeed will drop to 60kts, possible below stall speed.
Wind shear is when there is a dramatic change in wind speed or direction in a short altitude change.
The problem comes because the aircraft's momentum is related to groundspeed, but it flies by airspeed. So, you can go from an airspeed of say 100kts, with a groundspeed of 80kts with a 20 kt headwind. If that wind changes direction to a 20kt tailwind, your groundspeed remains 80kts, but your airspeed will drop to 60kts, possible below stall speed.
I think you need to think that through again.
Skyediamonds
Staff Sergeant
- 1,362
- May 26, 2018
No. I agree with tyrodtom. Gumbyk needs to rethink that again, especially ground speed.
Hence why a Boeing 747 can reach 825 mph over the North Atlantic and not break the sound barrier. Its ground speed, not airspeed.
On the topic of rotor blades:
What it's like to fly the new five-bladed H145 - Vertical Magazine
What it's like to fly the new five-bladed H145 - Vertical Magazine
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