Monthly Archives: May 2011

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?

Blue Angels' almost crash: the risk of Controlled Flight Into Terrain during formation aerobatics

On May 22, 2011, the US Navy Flight Demonstration Squadron was performing at Lynchburg Regional Air Show, Va, when the diamond formation went too low at the end of the “Barrel Roll Break” maneuver. As a consequence of the lower-than-normal maneuver, the Blue Angels aborted the show and all F-18s landed safely. Noteworthy, neither on the preceeding day’s rehearsals, for unknown reasons, the maneuver ended as expected with the break (to see how the maneuver should be performed have a look at the team’s website and select Maneuver 28).

The following video shows both the May 21 and 22 maneuvers.

Following the incident, the Blue Angels announced a safety stand-down and cancelled their next performances (so far, until mid June) for more practice at their home base Pensacola, Florida, and, on May 27, team’s leader CDR Dave Koss resigned and was replaced for the duration of the season by Capt. Greg McWherter, who was the previous Blue Angels’ Commanding Officer.

The incident was obviously a Leader’s fault. He entered the loop too low causing the diamond four-ship formation almost to hit the ground as happened in 1982, when the whole Thunderbirds T-38 formation crashed killing all four pilots (even if in that case the cause of the crash was a mechanical malfunction with the #1 aircraft control stick).

Formation aerobatics requires specific qualifications, experience and training as it’s not easy to perform aerobatic maneuvers. When many aircraft (up to 9 elements) fly formation aerobatics, it is important not only to maintain the correct distance from one another, but also to maintain a very reactive flight attitude: who flies up front is required to anticipate wind gusts, turbulence, and the appropriate corrections, absorbing as much as one can the oscillations in order not to propagate them amongst the rest of the formation. Instrument flight is reduced to the minimum. The artificial horizon is utilised for no more than 20 or 30 seconds during the whole display, this being flown “visually”, looking out, maintaining one’s own position by sighting the specific reference points. For almost all the duration of the performance wingmen and slot pilots, have “only” to follow their leader, almost disregarding their position relative to the ground.

Formation leader is the role with greater responsibilities: he guides the whole team, ensuring flight safety, dictating timings and managing separations, opposition passes and rejoins. For this reason, formation leaders are the most experienced pilots flying in a team. However, even the most experienced pilots can do mistakes and when such errors occur during vertical maneuvers, consequences can be tragic.

In 2008 I was attending an airshow when a brand new NH90 helicopter of the Italian Army, piloted by an experienced crew, crashed into the Bracciano lake after entering a Fiesler maneuver at low altitude and, probably, suffering spacial disorientation caused by the surface of the water.

The above picture was taken on Jun. 1, 2008. For more info visit the NH90 crash page. Image is watermarked.

Who called the “Knock it off”?

After watching the footage of the Blue Angel’s almost crash, I’ve had the opportunity to discuss with blog’s visitors and Twitter followers, who might have called the “knock it off” (a radio call reserved for safety of flight issues used to cease maneuvering).

As already explained, the team Leader has the responsibility of ensuring the safety of the formation. Many teams (as the Frecce Tricolori) have a  Commander who issues instructions from the ground to the pilots in the air to fine tune timings and distances in the various manoeuvres, supervising the display both from a technical and a flight safety perspective.  However, in the Blue Angels the Flight Leader is also the Commanding Officer, hence, most probably, it was #1 who radioed the safety order to the rest of the formation. Nonetheless, there are some maneuvers in which other formation members have specific responsibility to cross check heights and distances and during the whole performance, and above all, #4 has a demonstration safety officer role, as he flies at the lowest position in the diamond, from where he has a overall view of the formation. Maybe #1 failed to recognize the dangerous situation and #4 called the safety breakout. Unfortunately it is impossible to determine it but it owuld be extremely interesting to know whether it was the Leader or the Slot or another team member to radio the “knock it off” as it would give us an idea of the formation’ situational awareness.

Even if it is not among his tasks, each formation member can radio a call for a safety issue but it is an extremely unlikely situation, unless the call is made to inform the rest of the formation of a failure involving a single aircraft. Unsolicited safety calls are extremely rare even if the could prevent a so-called “Controlled Flight Into Terrain” (CFIT) of the formation. Military aviation counts thousands episodes of CFIT with wingmen recognizing a potentially dangerous situation earlier than their flight leaders but delaying too much the call that would have saved both lives for extreme confidence in the flight leader and respect of hierarchy.

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.”

Operation Unified Protector (was Odyssey Dawn) explained (Day 55 – 67)

Previous debriefings: Archive

After more than two months of air campaign, Unified Protector seems to be making a slow progress across Libya, even if the air campaign is far from being decisive against Gaddafi and his forces. At least, Misratah is no longer under siege. There’s no shelling on the city centre or on the port, that is open to the humanitarian aids flow. The turning point was reached when NATO started targeting Gaddafi’s capacity to resupply his forces on the front.

Source: NATO website

In the last Press Conference Wing Commander Mike Bracken, spokesperson of Unified Protector, admitted that the situation into the Berber Highlands and the western side of the country is difficult and concerning. He explained:

Here […] Pro-Qadhafi forces do not control the area, but they are putting the civilian, largely Berber population, under significant pressure from shelling in Yefren, Zintan, Nalut and the Wazin border crossing.

As a consequence many inhabitants have fled over the border to refugee camps in Tunisia and there have been skirmishes between rebel and pro-Qadhafi forces, as well as pro-Qadhafi forces and Tunisian forces along the border. However, in the Berber-controlled areas the rebels have resisted the pro-Qadhafi forces and now appear to be holding their ground.

NATO is focused on decreasing the pressure on the population by striking pro-Qadhafi units, and this strategy is clearly working.

Finally, moving to Tripoli. Here we have increased the pressure by striking military command-and-control centres. This has limited Qadhafi’s ability to give orders to his forces. It has also constrained his freedom of movement. Effectively, he’s gone into hiding.

On May 19, NATO hit 8 Libyan ships in the ports of Tripoli, Al Khums and Sirte. At Khums NATO hit a number of RHIBs (Rigid-Hulled Inflatable Boat) in the maintenance facility. The RHIBs were directly linked to the maritime operations of preceeding days when NATO interdicted a booby-trapped RHIB, leading to the discovery and subsequent destruction of one tonne of explosives at sea. NATO and partners used a number of communications channels to tell the pro-Gaddafi forces to lay down their arms and return to their bases and homes. “We have been stepping up leaflet drops and radio broadcasts to the pro-Qadhafi forces, telling them to move away from their military equipment, military installations and maritime assets” Bracken said. PSYOPS messages sent by the EC-130J using the very well known callsign “Steel 74” were heard before and after the attack on May 19, meaning that, most probably, there are other Libyan vessels being warned.

Loyalists are finding it harder to lauch attacks and to receive supplies, NATO has attacked an increasing number of Command and Control nodes but the news, announced on May 23, that both France and UK have decided to deploy some attack helicopters in theatre, shows that coalition partners are considering even other options to break the stalemate in the conflict. I’m not sure those being considered are the right options, though.

For sure attack choppers, such as the British AH-64 Apaches or the French Tigers, can be extremely effective if used to hit enemy tanks, convoys and vehicles, but they are also vulnerable to MANPADS, RPG and anti-aircraft fire especially if employed in Urban CAS scenarios. Those advocating the use of attack helicopters in Misrata or, generally speaking, in besieged towns, should not forget the lessons learned by the Apaches of the 11th Regiment during the attack on Karbala. Helicopters are the perfect tool for a certain kind of CAS (Close Air Support) and to support Special Forces, as the recent Osama Bin Laden raid in Pakistan shows. But they are not as effective if employed without the proper support of troops on the ground and when used against adversary forces that are too dispersed, intermixed with civilians and hidden (hence  not easily identifiable and targetable).

Flying at low altitude and speed, in spite of their countermeasures and armour, they tend to be subject to every kind of weapon the enemy can still own: from the small arms, to the mobile SAMs, to the MANPADS and also the RPGs. There’s an important difference between Close Air Support and Battlefield Air Interdiction (BAI): the first one requires boots on the ground; the second doesn’t; the first is what helicopters are perfectly suitable to (either as a support/anti-tank platform or as an escort/recon one); the second, is the most common kind of mission flown in Unified Protector.

Anyway, something like 3 or 4 British Apaches and an unknown number of French Tiger attack helos (or obsolete Gazelles), respectively embarked on HMS Ocean and Mistral class assault ship Tonnerre, will at least put some pressure on Gaddafi’s forces that will have to put out their hidden weapon if the want to try to hit them.
Without considering that, flying from ships, they will only be able to patrol the coastal regions and will not be capable to intervene on inland targets.

Other interesting things, information and thoughts:

1) Since the beginning of the NATO operation (31 March 2011, 08.00GMT) a total of 8019 sorties, including 3077 strike sorties, have been conducted. The trend is shown in the graph below. Air strikes represent on average among the 30% and 45% (with a peak at 48%) of the total sorties flown each day.

2) The Italian contingent was quite active during the last weeks. It performed 54 missions between May 13 and 20 with its Tornados (IDS and ECR), Typhoons, F-16s, KC-130Js and, now, also KC-767As and G.222VS. This proves that the war in Libya has been an unbelievable opportunity for many air forces and aircraft manufacturer to test new equipments, weapons and (most probably) tactics. After the Rafale, Gripen, Typhoon in the air-to-ground role (to name but few), the last new product to make its operational debut in Libya has been the recently formally accepted ItAF KC-767A. In fact, the new tanker was involved in air-to-air “refueling missions of Italian assets” involved in Unified Protector alternating in the AAR role with a KC-130J (that has been used since the early stages of Odyssey Dawn). Indeed, the 14° Stormo, based at Pratica di Mare airbase near Rome, has received the first aircraft on Dec. 29, 2010 and Mar. 10, 2011 and so far only Typhoons and Tornados have been qualified for refueling from the two wing stations (the aircraft uses also the boom refueling system used by US aircraft like F-15s, F-16s, B52s, etc.).

Noteworthy, even the only G-222VS in ItAF orbat (flown by air force pilots with mission crew belonging to other armed forces), already flying in the past few weeks for the Libyan crisis under national command, has been handed over to NATO to perform SIGINT activities.

Rendering: courtesy of Ugo Crisponi, AviationGraphic.com

Furthermore, on May 17, 2011, an Italian Air Force C-130J, departed in the morning from Pisa airbase, dropped about 400.000 leaflets over Tripoli, Libya. As reported by ANSA news agency, leaflets contained a message addressed to the Libyan people directly from the NTC (National Transition Council) that had asked Italy to deliver it to counter Gaddafi’s regime propaganda in Libya’s capital city.
The text of the message was:

Libya is one and its capital is Tripoli. Today we ask you to join and to take the right and wise decision. Join our revolution. Let’s build Libya away from Gaddafi. A unified, free, democratic Libya.

The mission was planned by the COI (Comando Operativo di vertice Interforze – Italian Joint Operative Command) and was conducted by personnel belonging to both the 28° Rgmt “Pavia, based in Pesaro and specialized in “operative communication”), the ItAF and the Intelligence Service. The airdrop took place from 7.000 mt (20.000 ft – the crew had to wear oxygen masks to operate at that altitude) from a position that was calculated taking into consideration many factors, among which the air temperature and humidity, the aircraft airspeed, the wind direction and intensity etc. Leaflets took up to 3 hours to touch the ground in Tripoli and surrounding areas.
The PSYOPS sortie was an Italian mission, not part of Unified Protector, even if NATO was obviously informed about the operation and supported it.

Even if Italy has conducted similar missions in Afghanistan using helicopters, this was the first time that the ItAF performed a PSYOPS mission dropping leaflets over a foreign capital since 1918 raid over Wien by Gabriele D’Annunzio (Aug. 9, 1918).

3) The Guardian has tried to understand “how much is each Nato country contributing to operations in Libya with the most comprehensive analysis yet of who is doing what in Unified Protector”. The article, titled “Nato operations in Libya: data journalism breaks down which country does what” is interesting as it provides a lot of data. Unfortunately, it contains also many inaccuracies (one time it provides the number of deployed aircraft, another one it gives a country’s number of aircraft under NATO command; there are errors about the deployment bases of some contingents; the consideration on the efforts are based only on the number of sorties and not on the type and/or number of dropped bombs; etc.).  Anyway, it is a good starting point for a more accurate in-depth analysis.

4) Thanks to the interesting pictures published at this website, we know that also UAE AF F-16s are flying air strikes (not only Mirage 2000s) with 2 GBU-12s, 4 AIM-120 AMRAAMs and SNIPER pod, as well as that Swedish Air Force JAS-39 Gripens, most probably, are not only flying reconnaissance missions, but also DCA missions with 3 drop tanks, 2 IRIS-T at tip pylons and 2 AIM-120s.

5) On May 21, a French Navy Super Etendard diverted to Malta Luqa airport for fuel problems while, on May 22, two Mirage F1s almost ran out of fuel on their way back to Solenzara airbase, in Corsica, and were compelled to perform an emergency landing in Olbia Costa Smeralda airport, in northeast Sardinia. These are only the last two episodes of a series of  French diversions caused by low fuel.  It looks like the French contingent is the only one experiencing such problems so frequently.

Another Iceland's volcano starts a new eruption: why is volcanic ash so dangerous for civil and military planes?

Airplanes have to avoid any airspace “polluted” by volcanic ash because ash can wreck the function of propeller or jet aircraft. Being extremely fine, the volcanic dust can easily invade the spaces between rotating machinery and jam it; furthermore, the silica melts at about 1.100° C and fuses on to the turbine blades and nozzle guide vanes (another part of the turbine assembly) which in modern aircraft operate at 1.400° C with catastrophic events. One of the most famous incident occurred in 1982, when a British B747 flew through an ash cloud from the Galunggung volcano in Indonesia and experienced the flame out its 4 engines. The aircraft was able to relight them only after plunging some 24.000 feet.

In April 2010, the European airspace was almost paralysed as a consequence of the eruption of the volcano Eyjafsallajokull, in Iceland. Many airports were closed and thousands commercial flights cancelled. Even military aviation was affected. On Apr. 15, five Finnish Air Force F-18 Hornet were involved in a training mission few hours before the imposition of airspace restriction caused by the subsequent ash cloud. Melted ash was found on the inside surfaces of one aircraft’s engine ispected using a boroscope. On Apr. 19, a US official said that several NATO F-16s suffered engine damage caused by glass build-up after flying through the volcanic ash covering a large part of northern Europe. Even southern Europe was affected. I was at Cervia airbase on Apr. 17, when the flying activity of the local-based F-16ADF of the 23° Gruppo had to be cancelled because the ash cloud had reached northern Italy. In these cases, training activities are postponed, exercises are cancelled or scaled-down and only operational sorties, such as air policing and national security missions (QRAs) are flown.

At around 19.30LT on May 21, 2011, Grímsvötn volcano in Vatnajökull Glacier. According to the first report by the UK Met office the plume height estimated by radar reaches 15.000 mt and it was also confirmed from an aircraft at 12 km or more. Even if geologists say that flight disruption is unlikely, a no-flight safety zone was established 120 nautical miles around the area as a precautionary measure.

Pinkfroot Blogs provides some interesting PlaneFinder’ screenshots of last year’s Eyjafsallajokull ash cloud affecting air traffic around London.

Below, you can see the UK Mef office chart (Apr. 19) and some screenshots I took using FlightRadar24 on Apr. 18 and 19, 2010, showing just a few airplanes able to fly along the most southern European routes.

The ItAF has a C-27J equipped with LIDAR (Light Detection And Ranging), a special equipement for the detection and measurement of airborne particles.