Silent rotor technology

Looks like the eurocopter program, called blue edge, may have had a breakthrough in silent rotors. Or at least came across whatever US operators are flying arounnd in. The program is called blue edge, and is used in conjunction with another program called blue pulse. Blue edge reshaped the blade, while blue pulse added flaps the flaps move to reduce the blade vortex interaction.

Silent rotor technology

I think this tech has been around for awhile. I've seem/heard what sounds like the silent tech over my house and over my area going back 10 years. The noticeable lack of repetitive "thud"/"whack", especially when they are gaining altitude quickly, always made me wonder WTF was going on with these, especially at night when there were what seemed like test flights or ariel searches going on (no spot lights though).

Do you know if current vehicles have this or is there a previous iteration, maybe even different tech, but still a noise reducing technology?

A few years ago I was driving over Salisbury Plain when a Chinook came over very low - hot day, windows down. I am used to Chinooks flying low where I live and they are very loud. This one made hardly any noise.

a reply to: GD
Uhhmm this story is literally 9 years old, there isn't anything new about this you realize? I remember reading about it years ago. Unless you can point to a new development or breakthrough.

Yes, such blades have been in use for years. And "silent" is an advertising gimmick, spin.

More quiet would be a better description. Combined with the 'fenestron' tail rotor, the French have been making more quiet helicopters for a long time.

originally posted by: Salander
Yes, such blades have been in use for years. And "silent" is an advertising gimmick, spin.

More quiet would be a better description. Combined with the 'fenestron' tail rotor, the French have been making more quiet helicopters for a long time.

Thanks for the reply. I figured that there had to be something that was different with them b/c I remember the same helicopters flying over my house when I moved in and it almost sounded like a rifle with a slow cycling automatic firing. These newer ones didn't have any of that, no thudding when right over head and as they moved away or approached, they were very hard to detect audibly - or at least you would have thought they were much further away than they actually were.

That's a pretty neat tech and I'll bet the choppers that did the Bin Laden raid had these. IDK if they make stealth helicopters. - Looked it up - answer is yes and yes.

en.wikipedia.org...

originally posted by: DigginFoTroof
I think this tech has been around for awhile. I've seem/heard what sounds like the silent tech over my house and over my area going back 10 years. The noticeable lack of repetitive "thud"/"whack", especially when they are gaining altitude quickly, always made me wonder WTF was going on with these, especially at night when there were what seemed like test flights or ariel searches going on (no spot lights though).

Do you know if current vehicles have this or is there a previous iteration, maybe even different tech, but still a noise reducing technology?

Interesting, what is your area? (or just name the nearby airbase respinsible)

originally posted by: DigginFoTroof
I think this tech has been around for awhile. I've seem/heard what sounds like the silent tech over my house and over my area going back 10 years. The noticeable lack of repetitive "thud"/"whack", especially when they are gaining altitude quickly, always made me wonder WTF was going on with these, especially at night when there were what seemed like test flights or ariel searches going on (no spot lights though).

Do you know if current vehicles have this or is there a previous iteration, maybe even different tech, but still a noise reducing technology?

Interesting, what is your area? (or just name the nearby airbase respinsible)

a reply to: GD

Oops

a reply to: GD

I saw a helicopter flying over California recently that could be heard within about 500 feet or so, as it passed over. Beyond that, you couldn't hear a thing.

originally posted by: oldcarpy
A few years ago I was driving over Salisbury Plain when a Chinook came over very low - hot day, windows down. I am used to Chinooks flying low where I live and they are very loud. This one made hardly any noise.

I don’t believe this (not you carpy the article) but:

theaviationist.com...

a reply to: DigginFoTroof

Just as there is no such thing as a silent helicopter, there is no such thing as a stealth helicopter, one unobservable by radar. It doesn't exist.

Advertising propaganda may call it that, but it's just advertising spin.

Osama died in 2001. www.legitgov.org...

The Abbottabad story falls into the same class as the Gulf Of Tonkin--pure hogwash meant to impress a most gullible media and public, rather like the other Obama project, Fast and Furious, exposed by Sharyl Attkisson.

a reply to: Salander

You know all of this how?

Google Kaman Aerospace and look at the blade technology that they developed. Increasing the number of blades will reduce turbulence and with that noise.

a reply to: JIMC5499

They found that with the C-130 too. The H model is getting an 8 blade prop. It dropped cockpit noise by like 15 db, and significantly reduced vibration on thr airframe.

a reply to: Zaphod58

I did a project for my ME degree that involved welded joints subjected to low frequency vibrations. There was a noticeable loss in strength. We are at the early stages of material science.

a reply to: Salander

Pretty sure you're off a bit on Mr. Osama's death date.

I'd just like to have a post here to look back on each day I come to the "live" screen.

I think it will give me comfort.

I'm all for silent rotors, and less vibration on the air frame.

a reply to: Woody510

40 years of paying attentionl

originally posted by: Archivalist
a reply to: Salander

Pretty sure you're off a bit on Mr. Osama's death date.

No, other papers wrote of it too. Bhutto spoke of his death too, just about a month before she was assassinated. Truth tellers are the first to go.

Willy & the Boys and Girls pulled another excellent deception "watching it happen". Another Grand Illusion by government and media.