In fact, these aircraft do not broadcast their ADS-B data but their position can be determined by means of Multilateration (MLAT).
MLAT (used by Flightradar24.com) uses Time Difference of Arrival (TDOA): by measuring the difference in time to receive the signal from aircraft from four different receivers, the aircraft can be geolocated and followed even if it does not transmit ADS-B data.
This means that the majority of the aircraft you’ll be able to track online are civil airliners and business jets that broadcast their callsign, altitude, position and speed via ADS-B in a cooperative way to let ground stations and nearby aircraft aware of their presence, whereas military aircraft (like the U.S. Special Operations aircraft daily flying over North Africa) equipped with Mode-S ADS-B-capable transponders can be tracked even though they are not broadcasting their position, because they can geolocated with MLAT.
What is happening right now over northern Iraq is at least weird.
A small aircraft or most probably a UAV, whose track appear to have originated from Turkey, is circling over northern Iraq, north of Mosul, being tracked by a feeder (a user with commercial off-the-shelf receiver available on the market) located in Erbil.
What’s unusual is that the aircraft, provided it is a UAV, is transmitting its data in the clear for everyone to see. Usually, aircraft (either manned or unmanned) performing clandestine missions can be tracked thanks to MLAT and not because their ADS-B transponder is turned on….
According to the Russian MoD, during the last few days the US-led coalition in Syria has deployed three times more drones than before with up to 50 Unmanned Aerial Vehicles often up in the air at the same time.
#SYRIA During some periods of time, there are more than 50 UAV’s in the sky over Syria simultaneously
The Russians claim that the coalition UAVs are conducting reconnaissance missions over oil fields along the Syrian-Turkish border which the terrorists allegedly use to smuggle oil into Turkey.
“You realize that with the scale of video monitoring being done, our colleagues could share information about what is going on along the Syrian-Turkish border and how much oil the terrorists are selling and where,” Maj. Gen. Igor Konashenkov, Russian Defense Ministry spokesman said during a press conference in Moscow.
RAF Tornados, supported by Voyager tanker and a Reaper UAV, have extended the UK’s airstrikes to Syria.
Hours after the UK parliament approved to extend the airstrikes to include Syria, Royal Air Force Tornado attack planes, deployed to Akrotiri, Cyprus, flew their first raid on terrorist targets inside Syria, early in the morning on Dec. 3.
The Tornados, supported by a Voyager tanker and a Reaper drone, dropped their Paveway IV guided bombs against six targets on an oilfield at Omar, “one of the ISIS’s largest and most important oilfields,” according to the MoD.
The six British “Tonkas” committed to Operation Shader flew their first mission against ISIS on Sept. 27, 2014 destroying the first ISIS target, a “technical” (an armed pick-up truck), in Iraq, on Sept. 30. Since then the RAF Tornado jets, have carried out hundreds of strike (and armed reconnaissance) missions against Daesh targets.
Although the payload may vary according to the type of mission the RAF Tornado GR4s have often carried a mixed load out with a single rack of three Brimstones and two Paveway IV 226kg bombs along with the Rafael Litening III targeting pod.
The Brimstone, is a fire-and-forget anti-armour missile, optimized for use against fast-moving platforms, first fielded during 2008 after an urgent operational requirement and used on the RAF Harriers during operations over Afghanistan.
With a warhead of 9 kg and a range of 7.5 miles, the Brimstones are an extensive redevelopment of the AGM-114 Hellfire and can be used on fast jets, helicopters and UAVs. They use a millimeter wave (mmW) radar seeker with a semi-active laser (SAL) that enables final guidance to the target by either the launching platform or another plane, and are perfect to destroy a vehicle with very low collateral damage risk, and an accuracy of about 1 – 2 meters. That’s why these small guided missiles have become the RAF weapons of choice since the Air War over Libya back in 2011.
Interestingly, one of the 8 RAF Tornados deployed at Akrotiri could be regularly tracked online during its transit from Cyprus to Iraq via Israel, Jordan, accompanied by a Voyager tanker: the example #ZA556 (the only “visible” aircraft in a formation of at least two planes) can be often spotted on Flightardar24.com as it flies into Israel, then into the Jordanian airspace before turning its transponder off to enter the Iraqi airspace.
Russia’s MoD has just released a video showing a Sukhoi (Su-30SM) more or less “intercepting” a U.S. MQ-9 Reaper drone over Syria.
Although Russia and the US have agreed on coordinating their air activity in the skies over Syria, several close encounters between Sukhois and American jets and drones have occurred in the past weeks: as already reported Russian jets deployed to Latakia, tailed U.S. Predator drones on at least three separate occasions during the first week of the RuAF air campaign.
The Turkish Air Force has shot down an unidentified UAV (Unmanned Aerial Vehicles) over the Syria-Turkey border.
Turkish Air Force jets, most probably F-16s flying CAPs (Combat Air Patrols) along the Syria-Turkey border shot down an unidentified drone that had violated the Turkish airspace earlier today.
According to the information made available so far, the Turkish combat planes issued three warnings to the (unmanned) aircraft before shooting it down. Although this may seem a bit odd in this case, as the one shot down was a really small model (resembling a Russian-made Orlan 10) larger UAS (Unmanned Air Systems), controlled by a Ground Control Station usually have radios to talk with the ATC (Air Traffic Control) stations: for instance, the famous U.S. Predator and Global Hawk drones have U/VHF radios that pilots operating from the inside GCS use to talk with the air traffic control agencies along the route.
Therefore, Turkish jets may have radioed three warnings to the drone, in spite of its size, because the current RoE (Rules Of Engagement) require them to do so when intercepting an unidentified, manned or unmanned aircraft
Following these border skirmishes, the Turkish F-16s began responding to “MiG” radar locks by performing lock-ons on the aircraft “harassing” them. However, it’s quite likely considered the type of target, that the drone shot down today was hit with a gun strafe instead of a missile.