Tag Archives: NORAD

Dissecting The Latest Close Encounter Between U.S. F-22 Raptors And Russian Su-35S Flankers Off Alaska

Let’s have a look at what happened in the airspace off Alaska a couple of weeks ago.

On the night of May 3, 2017, two Russian nuclear-capable Tu-95MS Bear bombers, this time escorted by two Su-35S Flanker-E jets, flew again inside the Alaskan ADIZ (Air Defense Identification Zone).

The “mini” package was intercepted by two U.S. Air Force F-22 Raptors some 50 NM to the south of Chariot, Alaska.

The Su-35 is a 4++ generation aircraft characterized by supermaneuverability. Although it’s not stealth, it is equipped with a Irbis-E PESA (Passive Electronically-Scanned Array) and a long-range IRST – Infrared Search and Tracking – system capable, (according to Russian sources…) to detect stealth planes like the F-35 at a distance of over 90 kilometers.

The Su-35S was deployed at Hmeymim airbase, near Latakia in Syria at the beginning of 2016, to provide cover to the Russian warplanes conducting raids in Syria in the aftermath of the downing of a Su-24 Fencer by a Turkish Air Force F-16. During the Syrian air war the aircraft carried Vympel R-77 medium range, active radar homing air-to-air missile system (a weapon that can be considered the Russian counterpart of the American AIM-120 AMRAAM) along with R-27T (AA-10 Alamo-B), IR-guided air-to-air missiles (however, the Flanker E jets escorting the Tu-95s off Alaska, did not carry any weapon.)

Shortly after being deployed to Syria the Su-35S started shadowing US-led coalition aircraft: a German Air Force spokesperson explained that the Russian Flankers were among the aircraft used by the Russian Air Force to shadow the GAF Tornado jets carrying out reconnaissance missions against ISIS; a VFA-131 video that included footage from the cruise aboard USS Eisenhower in support of Operation Inherent Resolve, in Syria and Iraq showed a close encounter with what looked like a Su-35S Flanker-E filmed by the Hornet’s AN/ASQ-228 Advanced Targeting Forward-Looking Infrared (ATFLIR) pod.

Although we have no confirmed reports of “close encounters” between the F-22 and the Flanker in the skies over Syria, what makes May 3 episode particularly interesting is the fact that this was the first time the U.S. Air force Raptors saw the Su-35S near the U.S. coasts.

Moreover, it’s worth noticing the “readiness in flight” posture of the stealth fighters.

Indeed, according to USAF, the Raptors were “committed” by North American Aerospace Defense Command to intercept the Russian aircraft while already in air patrol not too far away. It’s not clear whether the F-22s were already flying because involved in “Northern Edge”, Alaska’s largest and premier joint training exercise with MOB (Main Operating Base) at Joint Base Elmendorf-Richardson, or the CAP (Combat Air Patrol) was one of the measures introduced to enhance the readiness of the U.S. Air Force Air Defense assets as a consequence of the “unprecedented level activity of Russian bombers” recorded in the last months.

Anyway, the American premiere stealth fighters were already flying and thus could be quickly diverted by NORAD to “greet” the Russian package, this time supported by an A-50 Mainstay surveillance plane from distance.

The presence of Mainstay and Flanker confirms what this Author has already explained in the previous report about the key factors to take in consideration when planning a long-range strike sortie.

In my opinion the “mini package” was launched as a consequence of the increased flight activity in Alaska related to the Northern Edge exercise, confirming that the Russians closely observe what happens in the Alaskan area.

This time, they wanted to showcase their ability to plan a complex long-range sortie as well as the Flanker’s readiness to escort its own HVA (high value asset), the Bear, during operations at strategic distance.

The composition of this package is also worth a comment.

The presence of the Mainstay should not be underestimated. It was flying well behind the Flanker and Bear aircraft with a specific purpose. As an AEW (Airborne Early Warning) platform the A-50 is believed to embed some ESM (Electronic Support Measures): in other words, it is able to detect far away targets as well as able to sniff radar, radio and data link emissions. Furthermore, Raptors in QRA (Quick Reaction Alert) *usually* fly with external fuel tanks and Luneburg lenses: this means that they are (consciously) visible to radars. In such conditions, although it can’t “characterize” the clean F-22’s signature, the Mainstay can at least gather some data about the interceptors’ radar emissions (if any) and observe and study their tactics.

Therefore, as frequently happens on both sides since the Cold War, on May 3, the Russians most probably carried out another simulated long-range strike mission but with a precise ELINT (ELectronics INTelligence) objective: the Flankers and Bears were acting as a “decoy” package to test the American scramble tactics and reaction times, whereas the Mainstay, in a back position, tried to collect as much signals and data as possible about the US fighters launched to intercept them.



F-16, F-15 jets and KC-135 tanker aircraft took part in escort mission of unresponsive plane crashed off Jamaica

A Socata TBM-700 flown by a non-responsibe pilot crashed 14 miles off Jamaica, while enroute to Naples, Florida. Several U.S. Air Force plane took part in the escort mission.

On Sept. 5, a Socata TBM-700, N900KN, departed at 08.26LT from Rochester, New York, end en route to Naples, Florida, whose pilot had become unresponsive, crashed 14 miles off the coast of Jamaica, after running out of fuel.

The pilot had requested the Air Traffic Control to descend to a lower altitude because of a problem but became unresponsive as the TBM-700 was flying at FL250.

Military Radio Comms Expert Allan Stern monitored most of the flights involved in the escort of the unresponsive private plane and his logs helped us to draw a more detailed picture of the U.S. Air Force’s response to the emergency.


Image credit: U.S. Air Force

At 10.00 NORAD (North American Aerospace Defense Command) scrambled two F-16s out of McEntire ANGB, South Carolina, callsign “Stalk 52”. The two “Vipers” escorted the TBM-700 until they were reached by a flight of two F-15s, belonging to the Florida Air National Guard, out of Jacksonville, Florida, radio callsign “Lucky 01”.

The fighter planes were heard on frequency 141.625 talking one another about the TBM plane flown by a non-responsive pilot who was slumped forward.

Both tried to contact the pilot on VHF Emergency “Guard” frequency 121.5 MHz.

The interceptors were supported by “Gasman 02”, an Alabama ANG KC-135R, 58-0106, out of Birmingham AL, under control of NORAD’s Huntress on UHF frequency 260.9.

As the TBM-700 continued to fly southbound, they switched to Miami Control at Palm Beach, on frequency 270.325.

Later on, Stern heard “Stalk 52” as it was RTB (returning to base) to McEntire, telling NORAD’s Huntress on 228.9, that he was able to see the pilot slumped over, but that the pilot began to breath when the plane descended to lower altitude, indicating that he had been oxygen starved.

The two F-15s shadowed the unresponsive plane until it entered the Cuban airspace. The TBM-700, overflew Cuba and started to lose altitude approaching Jamaica. It crashed about 14 miles off the coast of Port Antonio, Jamaica at about  2:15 p.m. EDT.

Flightradar24 TBM700

Image credit: Flightradar24.com


Forget any security concern and welcome Air Force One on Flightradar24!

In my article titled Would modern transponders have made the hijacked planes visible to radars on 9-11? about Mode-S and ADS-B usage I wrote:

According to an esteem by Flightradar24.com, around 60% of the civil airliners and only a small amount of business jets and military aircraft have an ADS-B transponder. This means that, although you will never spot a Stealth Helicopter nor Air Force One broadcasting its position, speed, altitude and route on the Web, you can still catch some extremely interesting  planes. As the evasive US Air Force C-32Bs (a military version of the Boeing 757), operated by the Department of Homeland Security and US Foreign Emergency Support Team (FEST), used to deploy US teams and special forces in response to terrorist attacks.

I was wrong.

Although even the Flightradar24 FAQs confirmed that the Air Force One, the world’s most famous and important aircraft, should NOT be visible on their website, for a few seconds around 19.40UTC, the U.S. Air Force’s VC-25 (mil version of the B747), with registration 82-8000, transponder code 3614, advertised its position in the public domain while over Baltimore, descending through FL120 at 310 kts, heading towards Washington D.C. (for landing at Andrews AFB).

I don’t really know the reason for this quick appearance of the AF1 on FR24. A human error? A quick test? Hard to say. I’d expect the IFF Mode 5 with encrypted Mode-S and ADS-B to be paramount on the aircraft carrying the POTUS.

However, in the past I’ve witnessed some “doomsday planes” and other DoD flights shamelessly broadcasting on the Internet their position, altitude, track etc.

Let’s see what happens in the future. Maybe tracking Obama’s movements across the world will be possible. By means of a web browser….

Update Dec. 1, 2011: further investigation shows that the AF1 used genuine full ADS-B signal possibly triggered at the request of controllers for positioning purposes during descent to Andrews AFB.

Would modern transponders have made the hijacked planes visible to radars on 9-11?

As everybody know by now, on Sept. 11 2001, the first thing terrorists did as soon as they reached the cockpit of the four hijacked planes was turning the transponder off. This made the doomed planes almost invisible to the radars on northeast U.S. rendering the US Air Defense response to the attacks in New York and Washington DC extremely difficult.

In the aftermath of the celebrations for the 10th Anniversary of the 9-11 attacks, many visitors of this website asked me if the ADS-B transponders would have enhanced the capabilities of NEADS to identify and track the hijacked planes. This article answers that question.

[Read also: 9/11: a fighter pilot’s account]

What’s a transponder?

In aviation, a transponder is an electronic device carried by an airplane that operates as a radio receiver and transmitter. The transponder is the key component of the secondary surveillance radar (SSR) system. It produces a coded response upon radio-frequency interrogation: each plane is assigned a transponder code by the air traffic control agency, known as “squawk,” that is used to reply to interrogations with information such as the plane’s speed and altitude.

Data transmitted by the aircraft transponder is then displayed on the radar screen to assist the controller providing instructions and ensuring proper separations between flights.

When the aircraft turns its transponder off, it only passively bounces radio waves sent by the radar becoming a “non-cooperating” target in a primary surveillance radar (PSR) scenario: the pulse of radio energy sent out by the radar is reflected by the surface of the target plane back to the receiver providing the bearing of the aircraft from the ground station and its distance (calculated as the time taken by the pulse to reach the target surface and return).

Since only a fraction of the interrogation pulse is reflected back to the ground radar, the reply signal has a reduced range and is subject to signal attenuation. Hence, it can be difficult to detect.

For this reason on 9-11, after losing the transponder replies, FAA controllers were unable to determine with accuracy the actual position of the hijacked planes and transfer the information to the interceptors of the US Air Force.

Image source: ENAV


Next Generation airspace is based on another kind of system that not only improves radar accuracy and traffic avoidance for better safety, but also provides million users only “equipped” with an Internet connection, a web browser and a computer, the opportunity to follow the live air traffic all around the world as they were real ATC controllers.

The famous Flightradar24.com or PlaneFinder.net, both available also as iOS and Android apps, exploit the ADS-B (Automatic Dependent Surveillance – Broadcast). The ADS-B system uses a special transponder that autonomously broadcasts data from the aircraft’s on-board navigation systems about its GPS-calculated position, altitude and flight path. This information can be received by ground stations, by other nearby aircraft (thus enhancing situational awareness) and also by commercial off-the-shelf receivers available on the market as well as home-built ones.

Flightradar24 and PlaneFinder have a network of several hundred feeders around the world who make the flight information received by their home kits available for anybody. Obviously, only ADS-B equipped aircraft flying within the coverage area of the network are visible.

According to an esteem by Flightradar24.com, around 60% of the civil airliners and only a small amount of business jets and military aircraft have an ADS-B transponder. This means that, although you will probably never spot a Stealth Helicopter nor Air Force One broadcasting its position, speed, altitude and route on the Web, you can still catch some extremely interesting planes. As the evasive US Air Force C-32Bs (a military version of the Boeing 757), operated by the Department of Homeland Security and US Foreign Emergency Support Team (FEST), used to deploy US teams and special forces in response to terrorist attacks.

What if the ADS-B was used on 9-11?

Since ADS-B system uses onboard transponders, its use on 9-11 would not have improved the detection capabilities of the radars. ATC control centers would have remained as blind as they were during the attacks.

The only difference is that millions users would have been able to track the hijacked planes until their transponder were turned off and, minutes later, they would have seen all civil planes flying across the country diverting to the nearest airports while the US airspace was being shut down.

Top Image credit: Wiki

Air Force One journey on September 11: no escort during the attacks, 11 fighters when the airspace was completely free of airliners

Here’s the second episode of the 9/11 series. The first one, titled US Air Defense response to the September 11 attacks: known and unknown facts described how the NORAD reacted to the hijackings. This article will explain the tour across the US of the Air Force One on that day.

At  09.57 LT on Sept. 11, 2001, President Bush leaves Sarasota Bradenton airport, Florida on board the Air Force One. The Presidential VC-25 performs a rocket-like climb immediately after take off and climbs without any fighter escort. The first fighters that the VC-25 encounters enroute to Barksdale are two (even if some reported three or four) 147th FW Texas ANG F-16s from Ellington IAP.

That’s extremely weird, a tactical mistake that has almost no explaination. Long before President Bush left the elementary school where it was reached by the news of the terrorist attacks, arrangements would have been made to protect the POTUS before and especially after he had boarded Air Force One. We should not forget that we are in the middle of an air attack. The US Air Defense is almost unable to distinguish a normal civilian flight from one that is going to be hijacked and used as a weapon of mass destruction. For this reason, the entire US air space is shut down and all flights other than military and emergency ones are ordered to land as soon as possible.

Incredibly, in such a critical situation, the most important US airplane is left with no protection even if there was enough time to arrange it:  on 9/11 there were two airbases (Homestead and Tyndall) in Florida with fighters on 24-hour alert, that could be scrambled in about five minutes and reach Sarasota before AF1 departed.

Some might object that pursuing and hitting a mobile target is far more difficult than crashing into the World Trade Center or the Pentagon. However, at that time the US air space was not the safest place to be for the most important American citizen and the possibility of hijacked military planes or bizjets capable to intercept the VC-25 could not be ruled out.

As Col. Mark Tillman (pilot of the Air Force One on that day) recalls, initially, the AF1 was expected to go directly to its home base, Andrews AFB, located near Washington DC. The plan was to climb above any airliner in the 30K feet range of altitudes and go straight home. However, shortly after take off, the FAA ATC controller at Jacksonville Center called the Air Force One with the message:

“Air Force One, you have traffic behind you that’s descending into you. They are not talking to us and they are not showing off transponder”: a situation much similar to that of the hijacked planes. For this reason, the pilot performed a sort of evasive maneuver, flying westbound over the Gulf of Mexico: an airspace that it’s ringed by Air Force bases and it’s usually not used by airliners because of  many military training areas.

While Air Force One was overflying the Gulf of Mexico trying to escape a potential threat, the radio operator got a message from the Vice President at Washington: “Angel is next”, meaning that the Air Force One (Angel was at that time its classified callsign; the subsequent investigation found the original claim to be a result of miscommunication).

Few minutes later, Houston Center radioed another thrilling message:

“Air Force One, you have fast movers your 7 o’clock”.

Houston Center did not know who they were. They could be foreign nationals being trained in the US on Air Force or Navy planes, attacking “Angel”.

Eventually, the fast movers self-IDed as “Cowry 45”, a flight of two F-16s from Texas ANG, scrambled from Ellington, closing on their HVA (High Value Asset) at supersonic speed over the Gulf of Mexico: although some sources reported that airplanes were scramble from Tyndall, as said, the first aircraft to reach the AF1 were those of the Texas ANG.

“Cowry 45” intercepted the AF1 20 minutes after the alert scramble (after passing 90 minutes on “battle stations” waiting for the green light to take off), 50 miles off the Louisiana coast.

Finally escorted by fighter planes, Air Force One landed at Barksdale airbase at 11.45. One of the escort fighters stayed airborne to provide air cover while the other one also landed to refuel. To provide additional cover, Ellington launched two additional F-16s. While AF1 was taking off again from Barksdale at 01.30 pm, the F-16 orbiting overhead had to land to refuel as well, so three fighters escorted the POTUS to Offutt AFB, Nebraska, his next stop.

Air Force One landed at Offutt at 02.50 pm LT followed by its escorting aircraft.

It departed to Andrews AFB at 04.36 pm LT. A huge force was expected to meet the VC-25 and escort it across the country to Washington: four F-15s from Langley and four F-16s from Andrews along with the three Texas ANG F-16s that were miles behind it since they had taken off later and were struggling to catch up with the VC-25 flying at Mach .92.

However, to make their rejoin easy and give them the opportunity to make history (they were from Texas ANG, President Bush’s former flying unit) Air Force One performed a 360° turn after which it had 11 escort fighters: the F-15 were above it, the DC ANG F-16 on the left wing and the Texas ANG slightly behind.

Air Force One landed at Andrews AFB at 06.34 p.m. escorted on the very last part of the flight by two F-15s and one F-16s. Bush then reached the White House on Marine One helicopter, arriving shortly before 07.00 p.m. LT.

Concluding: Air Force One, the most important aircraft on the planet, flew without escort during the most tense moments of the 9/11 terrorist attacks, when no (civil) plane could be considered “friendly” to such an extent the airspace had to be shut down, but it finally got an escort of 11 fighter planes (a bit too many?) when the airspace was completely free of any civil liner.

Images: US Air Force