7500 — HIJACKING: What Happens the Moment an Israel-Bound Airliner Signals It May Be Under Hostile Control?
The attack aboard Flydubai Flight FZ1073 on Wednesday offered a rare real-world glimpse into one of the Israeli Air Force’s most sensitive missions: determining, within minutes, whether an approaching civilian airliner is simply experiencing an emergency — or has been seized and could potentially be used as a weapon against Israel.
The system is designed around one overriding problem: when the first warning arrives, the military may have no idea what is actually happening aboard the aircraft. A communications failure, mechanical problem, medical emergency, confused pilot, hijacking or deliberate terror attack can initially produce similar warning signs. The Air Force therefore has to react before the cause is known.
That is what happened Wednesday when FZ1073, a Flydubai Boeing 737 MAX 8 flying from Dubai to Ben Gurion Airport, began transmitting emergency signals while still well outside Israeli airspace.
Among the signals transmitted by the aircraft was transponder code 7500 — the internationally recognized code for “unlawful interference” with an aircraft. In aviation, the code can indicate that an aircraft has been hijacked or that someone aboard is attempting to seize control of it.
The signal immediately raised alarms in Israel. Contact with the aircraft was disrupted, its flight behavior became abnormal and Israeli Air Force fighter jets were scrambled as the security establishment worked to determine whether the aircraft represented a potential threat.
The plane ultimately diverted to Prince Sultan bin Abdulaziz International Airport in Tabuk, Saudi Arabia, where it landed safely. Flydubai subsequently confirmed that the passengers were safe.
What Israeli authorities learned afterward made the initial alarm considerably more ominous.
According to the preliminary Israeli account, one of the pilots attacked and stabbed the captain inside the cockpit and apparently attempted to crash the aircraft. Passengers and other crew members forced their way into the cockpit, overpowered the alleged attacker and helped enable another pilot to regain control.
Prime Minister Bibi Netanyahu subsequently said the alleged attacker “apparently tried to crash the plane with everyone on board.”
Defense Minister Israel Katz has characterized the episode as an “attempted jihadist terrorist attack.” Saudi authorities and Flydubai have not publicly confirmed that characterization, and the investigation into the suspect’s motive and background is continuing.
But for the Israeli Air Force, the eventual explanation is largely irrelevant during the first critical minutes of such an incident.
The moment an Israel-bound civilian aircraft begins behaving abnormally, military officials have to consider the possibility that the plane itself could pose a threat. They cannot wait to determine whether the cause is a malfunction, medical crisis, human error or hostile takeover before beginning defensive preparations.
Israel consequently maintains procedures specifically intended for suspicious or unexplained incidents involving civilian aircraft approaching its airspace.
Those procedures are not activated only after someone explicitly reports, “This aircraft has been hijacked.” An unexplained deviation from an assigned route, loss of radio communications, unusual flight behavior or an emergency transponder code can all trigger escalating scrutiny and a military response.
Aircraft transponders provide controllers with several internationally recognized emergency codes. Squawk 7700 indicates a general emergency. Code 7600 signifies a communications failure. Code 7500 indicates unlawful interference — most commonly associated with a hijacking.
FZ1073 reportedly transmitted 7700 before switching to 7500 as the emergency unfolded.
A 7500 signal is especially serious because pilots are trained to use it discreetly when circumstances permit. It allows a cockpit crew to alert air traffic controllers to unlawful interference without necessarily having to announce over the radio that a hijacking is underway.
But even 7500 does not, by itself, establish precisely what is happening aboard the aircraft. Controllers and military officials must still establish contact if possible, examine the aircraft’s course, altitude and behavior, communicate with surrounding aviation authorities and determine whether the crew remains in command.
Israel’s geographical size adds urgency to that process. An aircraft traveling at normal jetliner speeds can cover enormous distances in a matter of minutes, leaving relatively little time between the identification of a potentially hostile aircraft and its arrival near heavily populated areas.
The Air Force therefore maintains a continuous picture of aircraft operating around Israel and keeps forces capable of moving rapidly from routine monitoring to an operational response.
Once an aircraft is considered suspicious, fighter jets can be scrambled to intercept it.
An interception serves several purposes. Fighters can visually identify the aircraft, observe its condition and behavior, attempt to communicate with its crew and, when appropriate, escort it. At the same time, commanders on the ground continue receiving and evaluating information from military radar, civilian air traffic control and other relevant authorities.
Depending upon the circumstances, authorities can also alter civilian traffic patterns, restrict portions of the airspace or take other defensive measures while the aircraft’s status is being determined.
The goal is to answer several urgent questions as rapidly as possible: Who is flying the plane? Is the cockpit crew responding? Is the aircraft following instructions? Why did it deviate from its expected behavior? Is it attempting to land safely, or is it approaching Israel in a manner that could constitute a threat?
The fighter aircraft are therefore only the most visible part of a much larger response taking place simultaneously in the air and on the ground.
Senior military and political officials may also be drawn into the decision-making process depending on the severity of the incident. Wednesday’s Flydubai emergency triggered high-level consultations involving Netanyahu, Katz and senior defense officials while the aircraft’s status remained uncertain.
The Israeli Air Force routinely drills scenarios involving suspicious civilian aircraft precisely because there may be very little time to make decisions and incomplete information on which to make them.
Such exercises focus heavily on what the military describes as rapidly “closing the loop” — moving from the first indication of abnormal behavior to identification, information gathering and an appropriate operational response.
The process also explains why the scrambling of Israeli fighter jets does not mean authorities have concluded that a plane has been hijacked.
A civilian aircraft suffering a communications malfunction can appear suspicious. So can an aircraft whose pilots accidentally deviate from their assigned route. A serious mechanical failure can cause sudden changes in altitude or direction. A medical emergency can result in an unexpected diversion.
During the opening moments, military officials may be unable to distinguish among those possibilities.
Wednesday’s incident demonstrated that uncertainty in dramatic fashion. Early in the emergency, Israeli officials stressed that they did not yet have verified information proving that FZ1073 had been hijacked. Reports initially ranged from a cockpit altercation to a technical problem to possible unlawful interference.
As testimony from passengers and information from the cockpit emerged, Israeli officials increasingly came to view the incident as a deliberate attack.
Passengers described the aircraft plunging rapidly as the confrontation unfolded. Flight-tracking data showed the jet losing roughly 14,000 feet during the emergency, while passengers rushed toward the cockpit after hearing screams.
The alleged attacker was eventually subdued, reportedly with passengers using cables from the aircraft’s entertainment headphones to restrain him. A doctor and nurse aboard the flight treated the wounded captain, while additional pilots helped stabilize the aircraft and divert it to Saudi Arabia.
A senior Israeli official later said that “an extremely serious disaster was averted.”
Yet the military response began before Israeli authorities knew any of that.
From the Air Force’s perspective, an unexplained aircraft approaching Israel cannot simply be presumed harmless while officials wait for additional information. The threat has to be treated seriously until enough information has been gathered to determine otherwise.
That philosophy reflects one of the central lessons international aviation authorities absorbed from the September 11 attacks: a hijacked passenger aircraft may itself become the weapon. Once that possibility exists, the question is no longer solely how to rescue an aircraft in distress, but whether the aircraft could threaten people on the ground.
The Flydubai episode ultimately ended without the aircraft entering Israel under hostile control. FZ1073 diverted to Saudi Arabia, landed safely, and its passengers survived.
But for the Israeli Air Force, the response began much earlier — with a few digits transmitted from a civilian aircraft in the sky.
Until commanders knew why that code had appeared, they had to prepare for the possibility that the plane heading toward Israel was no longer simply a passenger flight.
{Matzav.com}