Tag Archives: Chinook

Malta International Airshow 2012 Highlights

Once again, the yearly Malta International Airshow, held on the Sept. 29 – 30 weekend, featured some of the most interesting and rare aircraft of the airshow season.

Among the highlights of the 2012 edition, held in the Sept. 29 – 30 weekend, the C-130J-30 Super Hercules of the Qatari Emiri Air Force and the CH-47 Chinook of the Free Libya Air Force.

Sunday Show’s Gran Finale saw a newly painted Air Malta Airbus A320 flying in formation with the Old Flying Machine Company Spitfire to Commemorate the 70 years of the George Cross.

The Red Arrows had to take part to the airshow but experienced technical difficulties on their way to Malta on Sept. 28 and had to divert to Decimomannu airbase, in Sardinia. Even the Free Libya Air Force Mirage F1 cancelled its “return journey” to Luqa.

Roderick Agius took the following interesting pictures of the airshow.

Image credit: Roderick Agius

 

One of the coolest helicopter night pictures, ever! Showing the famous Kopp-Etchell’s effect.

Made available by the 1st Brigade Combat Team, 82nd Airborne Division on Facebook, the following image is one of the most beautiful night shots I’ve ever seen.

It depicts a U.S. Army CH-47 Chinook helicopter loading troops at Ab Band, in Afghanistan.

Among the other things that make this picture so beautiful is the so called Kopp-Etchell’s effect. As the image title “Dust in the rotors” suggests, the seemingly solid rotor disks are caused by the sand hitting the metal blades and eroding their surface. Since the peripheral speed increases from the blades’ root to the tips, the erosion hence the visual corona effect is more visible near the blades’ tips.

The halo effect, caused by the oxidation of eroded particles, was dubbed “Kopp-Etchells effect“, by war correspondent Michael Yon to honor Cpl. Benjamin Kopp, and Cpl. Joseph Etchells, two fallen American and British soldiers.

Although much beautiful, the visual corona is also dangerous for the helicopter, because it makes a low flying or landing chopper not only clearly audible, but also clearly visible from distance.

Image credit: U.S. Army / 1st Brigade Combat Team, 82nd Airborne Division

CH-47 shot down by an RPG rocket: second episode in less than two weeks

On Aug. 6, an Army National Guard CH-47 with 38 on board, including 19 Navy Seals was downed by a rocket-propelled grenade in eastern Afghanistan. It was the worst incident of the war in Afghanistan as the Afghanistan war as it approaches the 10-year mark. Hundred articles and comments have been published all around the world, but none of those I’ve read so far, has recalled a similar incident that took place only few days before, when another Chinook, operating in the same region was hit by an RPG shot.

On Jul. 25, in what had been considered “a rare incident”, another CH-47 was hit by an RPG rocket and forced to perform a (successful) crash landing. Fortunately, everybody escaped the downed chopper and there were only two slightly wounded.

So, less than two weeks before a CH-47 and its passengers were killed by an RPG rocket, another unguided rocket had hit the same type of helicopter, in similar circumstances and almost with the same consequences.

The helicopter downed in July was carrying US and Afghan soldiers to Nangalam Base, in the Pech River Valley, in eastern Afghanistan and the crash happened shortly after midnight.

Since the RPG is a launcher of unguided rockets, hitting anything even at a few hundred meters is extremely difficult and requires a certain amount of luck. Even if the target is a large chopper. For this reason, an interesting article published few days after the Jul. 25 incident by Strategy Page talked about a “miracle shot”. A miracle that, unfortunately, repeated on Aug. 6, with a death toll of 38.

According to the Strategy Page article, the CH-47 hit on Jul. 25 was the 17th helo brought down by hostile fire in Afghanistan (with another 84 crashed for non-combat reasons).

In most cases, helicopters are brought down machine-guns, especially heavy (12.7mm or larger) ones. The enemy has also been using portable surface-to-air missiles since 2003, including more modern models, like the SA-16 (which is similar to the American Stinger.) American helicopters are equipped with missile detection and defense (flare dispensers) equipment. Thus the most dangerous anti-aircraft weapon remains the machine-gun. However, aircraft losses to ground fire have been declining every year, mainly because of improved defensive tactics.

Helicopters are fired on about six times more frequently than they are hit, and most of those hit are only slightly damaged (and land normally). Today’s helicopters are much more rugged and reliable than those in Vietnam (1966-71, the first major combat use of helicopters). There, 2,076 helicopters were lost to enemy fire (and 2,566 to non-combat losses). In Vietnam, helicopters flew 36 million sorties (over 20 million flight hours). Helicopters were used much less in Iraq, where no more than half a million hours a year were flown (to support a third as many troops as there were in Vietnam during the peak year). In Vietnam, helicopters were about twice as likely to get brought down by enemy fire. As in Iraq and Afghanistan, the main weapons doing this were machine-guns.

Today’s helicopters are more sturdy, partly because of Vietnam experience, and are more likely to stay in the air when hit, and land, rather than crash.

Unfortunately, not enough sturdy to absorb an RPG “miracle shot”.

There’s no way to procted an helicopter from an RPG rocket other than flying unpredictable paths at very high speed, an attitude that can be maintained only for some phases of a mission. Surely not when the helicopter is heavy or close to the ground during take off and landing.

Wired’s Danger Room reports that new helicopter countermeasures are currently under test and could be deployed in combat on CH-47s well before the current deadline (2017), following last week end tragedy.

However such defensive systems react after the first shot, preventing the shooter from taking a second shot. The risk is that Taliban shooters, who seems to be more accurate with their rockets than the past, as the Jul. 25 and Aug. 6 incidents show, may be able to hit the target with their first shot, rendering the countermeasures useless.

China has already reverse-engineered the Stealth Black Hawk

Those who were worried that China could get its hands on some pieces of the ill-fated chopper that crashed in the Osama Bin Laden compound to reverse-engineer the Stealth helicopter have to accept the unpleasant reality that the Chinese have already copied it. As a matter of fact, on May 23, 2011, Dragon Models (based in Hong Kong, China) announced a new model (to be released in July): the 1/144 scale Stealth Helicopter “Operation Geronimo” (Twin Pack).

Image: Dragon Model Limited

If you look at the artwork on the box, you’ll notice that the one created so quickly by DML is quite similar to the concept I developed with Ugo Crisponi. It has the same (fictional) intakes and exhausts, and the overall shape is almost identical. To be honest it also includes some of the inaccuracies of our famous MH-60X rendering (dated May 5) that we fixed in a subsequent “release” (published on May 17) and a few more (based on the artwork, the blades seem quite unrealistic while the horizontal stabilizers are different from what the pictures suggest).

Anyway, here below you can find the May 5 sketch and if you compare it to the above image, you’ll see that, most probably, I and Ugo had the same ideas about the Stealth Black Hawk as the Dragon graphic designers. Noteworthy, the model comes with the unofficial/unconfirmed raid’s codename, since the official one is Operation Neptune’s Spear and not Operation Geronimo (“Geronimo” was the codeword for Bin Laden’s capture or death).

Above: the Stealth Black Hawk rendering I published on this site on May 5. Below the new version issued today (May 31, 2011).


Here’s an excerpt of how Dragon introduces its new model:

[…] Looking like a mixture of MH-60 Black Hawk and F-117 Stealth Fighter, this mysterious helicopter from the 160th Special Operations Aviation Regiment (SOAR) has distinctive edges and angles. The fuselage, nose and tail were all modified to reduce the craft’s radar cross-section.

[…]Befitting the innovative and ultra-secretive shape of the helicopter, this model is newly tooled in every aspect. All the low-observable features such as the angled surfaces are carefully rendered. […]

To be or not to be [Stealth]: that is the question

If Drangon dared to venture into a Stealth model about which we still know very little (even if a 1/144 scale is small enough to “hide” some unknown details), Italian model manufacturer Italeri, took a different approach. Instead of producing a small kit of the Stealth Black Hawk basing on few pictures or artworks they announced a larger 1:48 UH-60/MH-60 Black Hawk “Night Raid”. The model box in this case is depicted performing a “generic” Special Forces operation inside a compound in Afghanistan (or Iraq).

Italeri told me that they have decided not to launch a product that, most likely, would have been quite different from the real Stealth Black Hawk, given the few images and known facts available to date. So they released a “normal” Black Hawk even if they are ready to work on a realistic “Silent Hawk” as soon as new details about the modified MH-60 used in the OBL raid will surface.

Whatever the choice (stealth or not stealth), such a quick reaction by both Dragon Models and Italeri shows how fast the response to a news story (and to the subsequent market demand) can be.

Dealing with the daily updates about the OBL raid and the Stealth helicopter, here’s an interesting news: on May 30 some media reported the (unconfirmed) news that two helicopters crossed the border between Afghanistan and Pakistan to take five Taliban members in North Waziristan, and bring them back across the border into Afghanistan. This article provides an interesting analysis of the episode. Obviously, I’m not suggesting Stealth Black Hawks were involved again; however, given that the targets were high-value ones and that this kind of mission (once again in “enemy territory”), if confirmed, would be probably carried out by Special Forces, who knows?

Introducing the Stealth Little Bird (based on a true story about the silent "black" OH-6 used during the Vietnam War)

I’ve already written a lot about the Stealth Black Hawk, whose existence is proven by pictures taken at Abbottabad the day after Osama Bin Laden raid, and about a Stealth Chinook theoretically taking part in Operation Neptune’s Spear. However I hadn’t thought about another stealth helicopter possibly flying in Pakistan during the OBL raid until I saw a video of a 160th SOAR rescue mission in Iraq that reminded me that the Night Stalkers often fly mixed formations of Black Hawks and MH-6 Little Birds, smaller choppers conducting, for example, rooftop insertions of Special Forces. The 160th SOAR is equipped with both MH-6s and AH-6s, the attack version of the Little Bird, aircraft that were used in almost all US (special) operations: from Op. Urgent Fury (1983, Grenada) to Just Cause (1989, Panama) to Gothic Serpent (1992, Somalia) to Iraqi Freedom (since 2003) the MH-6s have been a constant presence within some of the most difficult operations involving Delta Force and Navy Seals. In 2009, AH-6s took part in the helicopter assault (involving Navy Seals) to kill wanted terrorist Saleh Ali Saleh Nabha in Baraawe, Somalia, taking off from a US vessel. Having imagined the possible shape of a Stealth Black Hawk and Chinook, why not consider the possibility that even a modified, quieter, stealth MH-6X took part in the OBL raid flying with the 160th SOAR? I know that there’s almost nothing that can give some credence to this theory especially because another Stealth helicopter on the scene would make the air space over Abbottabad too crowded. However, I wanted to give it a try and hear what my readers think about a Stealth Little Bird. So, once again, I’ve asked Ugo Crisponi to help me with a rendering of a fictional “Black” MH-6 (6-bladed main rotor and 4-bladed tail rotor) that could be obtained with some modification of the original Little Bird:

I’ve just said that there is “ALMOST” nothing to give credence to the new theory of a Black fleet made by Stealth Black Hawk, Chinook and Little Bird. In fact, a highly modified “Black” Hughes 500s, was used by the CIA in 1972 from a Laos base. An extremely interesting article published in 2008 by Air & Space recalls the story of two OH-6As which were modified to fly with Air America and “to quietly drop off and pick up agents in enemy territory”. Dubbed “Quiet One”, the somehow stealth helicopters conducted their secret mission, on Dec. 5 and 6, 1972, when they carried in N. Vietnam commandos to place a wiretap and a solar-powered relay station that enabled Americans to eavesdrop communications on a telephone line used by the enemy commanders.

The article, written by James R. Chiles, provides some interesting details about the “Quiet One”:

The slapping noise that some helicopters produce, which can be heard two miles away or more, is caused by “blade vortex interaction,” in which the tip of each whirling rotor blade makes tiny tornadoes that are then struck by oncoming blades. The Quiet One’s modifications included an extra main rotor blade, changes to the tips on the main blades, and engine adjustments that allowed the pilot to slow the main rotor speed, making the blades quieter […]. The helicopter also had extra fuel tanks in the rear passenger compartment, an alcohol-water injection system to boost the Allison engine’s power output for short periods, an engine exhaust muffler, lead-vinyl pads to deaden skin noise, and even a baffle to block noise slipping out the air intake.

The extensive alterations did not blank out all noise, Taylor says. Rather, they damped the kinds of noise that people associate with a helicopter. “Noise is very subjective,” he says. “You can reduce the overall noise signature and an observer will still say, ‘I can hear it as well as before.’ It’s related to the human ability to discriminate different sounds. You don’t hear the lawnmower next door, but a model airplane is easily heard. It has a higher frequency and seems irritating.”

It also explains that some Quite One’s modifications can be found on later choppers:

“The agency got rid of it because they thought they had no more use for it,” says Glerum. At least one of the ex-Quiet Ones surfaced years later at the Army’s Night Vision & Electronic Sensors Directorate in Fort Belvoir, Virginia.

But according to the participants, no more were built. It’s puzzling why the CIA did not keep a stable of Quiet Ones, at least while the technology remained under wraps. And it remained a secret for more than two decades, until Ken Conboy and James Morrison told the story in their 1995 book Shadow War.

But there were valid reasons for dropping the Quiet One from the spymasters’ catalog.

“In the long run, the 500P was not the best for setting wiretaps,” says Casterlin. “It was not good for high-altitude work.” It was a light helicopter and had to be loaded with gear that cut into its payload capability and operating altitude. The Twin Pack was much louder but also simpler to run and more powerful, so Air America used it for later wiretap missions in North Vietnam. At least one tap, placed on the night of March 12-13, 1973, was successful.

Some of the Quiet One’s innovations did show up on later helicopters, including the Hughes AH-64 Apache, which has a scissor-style tail rotor. And Hughes engineers’ interest in modifying the tips of the main rotor blades to cut the slapping noise caused by blade vortices has been taken up by other experts. Aerospace engineer Gordon Leishman and his team at the University of Maryland, for example, are developing a blade with curved tubes at the tip to divert the air, thereby countering vortex formation. But, thanks to its many unusual modifications, the 500P still holds the title that Hughes gave it in April 1971: “the world’s quietest helicopter.”