The Technology Behind the New Stealth Helicopters

Like many of you here, I have recently seen the images of the downed helicopter used in the raid to capture/kill Osama bin Laden. I love seeing new technology! The latest concept cars have always been a favorite. Nothing like seeing the newest Lamborghini or any other far-out concept for that matter.

To me, the holy grail of super advanced hi-technology is very rarely seen and is almost always developed for use in military purposes.

The aircraft that are developed and used in ultra secret missions are some of the most gaurded secrets that any military can have. It seems to be about time for some new technology to be dropped in the laps of the civilian world for us to marvel at. Even if it was an accident for us to get our eyes on, at least a piece of, the newest toys the US military now employs on it's most high profile missions, where success hinges on our troops having every possible advantage and head start over the enemy.

I was left wanting more from some of the recent information I found about the downed 'stealth' helicopter and decided to do a little searching for more information on what type of technology these super-secret choppers may use to gain an edge over other military forces, continuing to place the controllers of this hi-technology at the fore-front of world powers.

Here is what I have found:

Helicopters are loud and maybe more noticeable than airplanes, because they often times fly so much closer to the ground and use blades that are designed for maximum lift and control. Silent blades have been designed and, according to some of the early CGI images, seem to be depicted as a part of the new stealth helicpter desing.

SOURCE

Helicopters are so loud because their blades create turbulence as they pass behind one another in their own wakes. The phenomenon is called a “blade-vortex interaction,” and it makes for that thwop-thwop-thwop sound signature to helicopters.

By changing the shape of the rotor blades — the new product is called “Blue Edge” — Eurocopter has reduced the blade-vortex interaction enough to allow for a sound reduction of just three to four decibels.

Now that’s quiet.

This revolutionary main rotor blade provides a passive reduction in noise levels, using a double-swept shape that is very different from present-day blades. The aim of this program is to reduce the noise generated by so-called blade-vortex interactions (BVI), which occur when a blade impacts a vortex, created at the tip of the blade of any helicopter.

A five-blade Blue Edge main rotor has been flying since July 2007 on an EC155 testbed, logging 75 flight hours and demonstrating noise reductions of 3 to 4 dB, as well as very good performance of the blade. With this safe and simple means of measureable noise reduction for helicopters now validated, Eurocopter is ready to move Blue Edge into production applications.

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Don’t believe it? Here’s a video of the rotors in action:





The recent raid may have also brought out one of the projects that has been tested in years past at the highly secretive Groom Lake Facility, better known to many as Area 51. The following test reveals a bit more information on this and the full article can be found HERE - source

Stealth Helicopter
MH-X Advanced Special Operations Helicopter
On 1 May 2011, the United States announced that it had launched an operation into Pakistan from Afghanistan to apprehend Al-Qaeda leader Osama bin Laden. Bin Laden was killed during the operation, reported to have been conducted by members of the Naval Special Warfare Development Group (DEVGRU; commonly referred to by an older title, Seal Team Six). The Naval Special Warfare operators were reported to have been inserted and/or extracted by elements of the 160th Special Operations Aviation Regiment (Airborne). During the raid, it was reported that one of the force's MH-60 helicopters was damaged and had to be destroyed in place. The remnants of the helicopter were later recovered and moved from the site by the Pakistani military. Subsequent pictures of the wreckage suggested that the helicopter might have in fact been a new type, possibly incorporating stealth technology.

The U.S. Army and CIA developed what could be considered a stealthy helicopter during the Vietnam War. There, they were primarily interested in reducing the amount of noise that the helicopter generated, and they named the helicopter The Quiet One. Light, quiet and stealthy helicopters could be used for clandestine missions, quick in-and-out assignments without being noticed. A Special Forces A-Team performing an extraction could grab their target, climb a rope, and be extracted by a stealth helicopter. Other stealthy helicopter has focued on reducing detectability by radar and infra-red sensors, including the suppression of hot engine exhaust gases.

In the 1980s, Hughes and other American aircraft manufacturers investigated concepts for the construction of radar-evading "Stealth" helicopters. The US designed stealthy helicopter-type aircraft. One program was the McDonnell Douglas X-wing. Stealth features of this hybrid craft included using the stalled blades, when in aeroplane mode, as radar reflectors, and using McDonnell Douglas NOTAR (no tail rotor) technology to eliminate tell tale tail rotor radar signature. The X-wing project had an unclassified counterpart, which allowed components of the 'black' X-wing to be obtained under cover.

According to one report, a classified stealth helicopter was being tested at the Groom Lake Air Force base as early as 1990. The code name for the helicopter as "T.E.-K," standing for "Test and Evaluation Project K." The F-117 stealth fighter was reportedly known as "T.E.-A," and the B-2 stealth bomber, known as "T.E.-B." The 2/6/95 issue of Aviation Week & Space Technology reported that the Air force had a silent NOTAR helicopter and a stealth helicopter inside Area 51....

OK, so we have the noise from the blades eliminated, which is a major boost to stealth operations, but it isn't truly stealth in the way many military program experts know stealth. To achieve that type of stealth you need to be able to avoid RADAR.

Below is an image of the RAH-66 Stealth Comanche helicopter. It was canceled in 2004 before ever being used in the field, or so the wiki page says....

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SOURCE

The Boeing/Sikorsky RAH-66 Comanche was an advanced U.S. Army military helicopter intended for the armed reconnaissance role, incorporating stealth technologies. It was also intended to designate targets for the AH-64 Apache.[2] The RAH-66 program was canceled in 2004 before it was fielded

Prototype flight testingThe first Comanche prototype was rolled out of the Sikorsky Aircraft's helicopter production facility on 25 May 1995.[7] The prototype's maiden flight occurred on 4 January 1996.[8] Flight qualification tests and evaluations were conducted for the two DEM/VAL (Demonstration and Validation Phase) prototypes. Through the early 2000s, the U.S. Army planned to purchase over 1,200 Comanches to fill the scout and light attack roles, with deliveries of operational RAH-66s beginning in 2006.[9]...

I find the next part interesting, because it is stated that the technology resulting from the testing of this helicopter was to be incorporated into future choppers;

CancellationOn 23 February 2004, the U.S. Army announced their decision to cancel the Comanche helicopter program in view of the need to provide funds to renovate the existing helicopter fleet of aging attack, utility, and reconnaissance aircraft.[10] The Army also planned to use Comanche program funds to speed up unmanned aerial vehicles (UAVs) development.[11] UAVs have been providing reconnaissance during military operations in Afghanistan and Iraq. About US$6.9 billion had been invested in the Comanche program at the time of its termination.[1] An additional US$450–680 million was paid for contract termination fees to main program partners Sikorsky and Boeing.[12][13]

Technology developed for the Comanche is expected to be integrated into the Apache and other U.S. military helicopter developments [citation needed] The Army was developing the Bell ARH-70 to replace the OH-58D in place of the RAH-66, but after cost overruns, the ARH-70 was canceled in October 2008 as well.

Design

It incorporated stealth features to avoid detection, such as retractable weapon stations and main gun, and stealth faceting and radar absorbent materials...

The Comanche's very sophisticated detection and navigation systems were intended to allow it to operate at night and in bad weather...

I really wish I had been interested in this BEFORE the recent raid, as the web is flooded with stories about the stealth copter, making it very hard to find information about the stealth choppers and the technology being developed for them.

The Wiki information seems to be very good however. Many are saying that the chopper was indeed a Stealth BlackHwak, while there are conflicting reports of some saying it resembled a Comanche type helicopter (I may be mis-remembering this, they either said it resembled a heavily modified Apache or Comanche)

If it was a Comanche helicopter, could it be the same helicopter that was tested in the early 2000's at Area 51 and presumed to be a cancelled project?

I hope this gives a bit of information that you may not have seen about the technology going into these choppers.

If you know of other technology that has been/is being developed for use in these state-of-the-art aircraft, please share it in this thread, I would love to see some of the new stuff that is making it's way into the hands of our troops and ultimately protecting us here at home.

Thank You! to our Men and Women serving overseas and around the world! We love you all and hope for your safe return home to your families soon!

My question is...Where the hell have they been hiding this and how did they get the funding to make it?
Are we really hurting for money or is the government acting like it is to build its black projects?
How did it not leak??? They had to transport it over there some how. If it was on a carrier someone would have leaked it. Which tells me there is a secret US base over in Europe some where working on black projects.

reply to post by johngrissom


well, I imagine there are so many things we do not know about, it is staggering.

I am sure the people who would be using this type of technology would also be the same type of people who are going on the ultra secret missions and can be trusted to keep these types of secrets.

After all, all the government really has to do is deny, deny, deny and the people will buy, buy, buy

I am sure we are not hurting for money, not as the government/s would have us believe, as most, if not all monetary systems of the world are based on something that is not really real.

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Found this on the interwebs.
A possible look for the chopper that was downed. I'd say it's a good estimate of what it looks like.

Great post OP...

On a related note, perhaps one of the kids seen scaveging parts from the chopper will be kind enough to post up some pics?? You never know, we have members all over the world...

Fascinating post.I don't think leaving even a tail section was a good idea the downed stealth parts from Serbia were handed out to various governments to copy apparently culminating in the Chinese unveiling their own stealth fighter.But they probably couldn't remove it.

This is a previous thread on the choppers which has some good info and pics...has some of the same stuff put in this OP...but one of the pics on this thread show that the Main Rotor Assembly and fuselage does not EXACTLY match the artists conception...but is probably not too far off.

www.abovetopsecret.com...

Not sure about you guys and the stealth thing, I imagine a lot of people would like it to be, but I honestly think it is just a shield to stop small arms fire form getting into the tail rotors. Nothing more, and that simple.

Stealth on a chopper would be sound reduction and heat dispersant, but nothing is going to hide a chopper, the sound can only be masked to an extent, and then your going to hear it no matter what.

The Comanche is the stealthiest rotatory wing craft we have, and even it is not silent.

Then again what do I know, was only in the Cavalry...never seen a helo up close..nah never.

The way I figure it, what the public see's is always 20 or so years behind what the military has developed and is using in black ops missions.

If they allowed this stealth helicopter to be seen by the public eyes, then what they have in development must be much more hi-tech.

Originally posted by ADVISOR
Then again what do I know, was only in the Cavalry...never seen a helo up close..nah never.

As you have worked in close proximity to helicopters, can you answer me a question?

I was completing a contract on a Canadian military base when some helicopters were coming in from training. One of the ground crew (I assume) told us to 'watch and listen'. We thought we were supposed to watch them land. We were very suprised (to say the least) when two passed right over top of us from a spereate direction. We never heard them coming. Have helicopters been able to minimize the noise for a long time now? Or do multiple helicopters mask the noise of how many are actually around?

I was clearly able to hear the sound of each one that I was looking at (even able to tell which was making each sound), but the ones from behind...nothing. It has really intrigued me since.

reply to post by ADVISOR


Advisor, the Comanche project was actually killed in 2004 by Gates. Well, that was the story anyways, now it looks like it was simply folded into a deep black project/existing upgrade Helo projects. As in why just do a small two seater recon Helo when there are so many other ways to do recon/real time battlefield intel.

Now it looks like the tech was adapted to upgrading the UH-60 airframe, avionics and other countermeasures.

Materials and Electronic counter measures not to mention physical design nowadays can greatly reduce radar/heat and also now noise signatures.

Check the link to the other thread I put above your last post, it has other links to other articles where they talk about flight profiles(how you fly the helo) as well as rotor speed and RPM's can really make a helo MUCH quieter. Of course...you are right you can't make it silent, but the information in those articles confirm that there is such a thing as a stealthy helicopter nowadays.

Also, any further info you have from your days working with Helo's would be of interest to me, so please don't hesitate to share some of your personal experiences.

I'd just like to point out that there is no such thing as a silent rotor, and all
these articles/sources rely heavily on word play.

If you want to argue semantics, a silent rotor would have an acoustic output of 0dB.

However the phrase used is "reduction of 3 to 4 db". keyword here is "of" ie. the "silent"
rotor is just 3 or 4 dBs less loud than a conventional one. Which is still quite loud and very
noticeable.