The minimum altitude dispute between a Turkish Airlines A321neo aircraft and ATC at Muscat Airport brought the differences between MVA–MSA and pilot responsibility to the forefront.

The ATC–pilot dialogue that took place in the approach airspace of Oman’s Muscat International Airport (MCT) and emerged through radio recordings brought important technical issues in terms of aviation safety to the agenda. In the incident, a Turkish Airlines Airbus A321neo departing from Istanbul experienced a disagreement with air traffic control regarding minimum altitude during the approach phase.

While the approach controller instructed the aircraft to descend to 2200 feet, the pilot stated that this instruction did not correspond with the Minimum Vectoring Altitude (MVA) / Minimum Sector Altitude (MSA) values shown on their flight charts and reported that they could not descend below 3600 feet.

MVA – MSA – ATC Area of Authority

Technically:

MVA refers to the lowest safe altitude that ATC can assign to aircraft during radar vectoring and is displayed on the controller’s screens.

MSA, on the other hand, appears on the approach charts used by pilots and represents a more conservative altitude that also includes navigation error tolerance.

The notable point in this incident was that ATC issued the instruction relying on its own MVA value, but this altitude could not be verifiably confirmed on the charts available to the pilot. According to international procedures, a pilot has the right to refuse to descend to an altitude that cannot be confirmed on their charts.

“Instruction or Order?” Debate

The controller’s emphasis on “orders are orders” in the radio communications opened up a separate discussion topic in terms of aviation terminology. According to ICAO standards:

• ATC gives instructions,
• The pilot is the ultimate authority responsible for the safety of the aircraft.

For this reason, a pilot may refuse an instruction, using appropriate phraseology, if they believe it would put the safe operation of the aircraft at risk. It is observed that the Turkish Airlines pilot established calm, clear and procedure-compliant communication at this point.

Chart Inconsistencies and Company Procedures

The incident points to an issue frequently encountered in international operations:

At some airports, ATC MVA values may not be clearly shown on the EFB/Jeppesen/LIDO charts of all airlines. In such cases, many companies adopt the principle of “do not descend to an altitude that cannot be confirmed on the chart”.

The pilot’s statement, “we cannot accept the vectoring due to company procedures,” is considered a reflection of this conservative safety approach.

An Example in Terms of CRM and Cockpit Discipline

When the radio recordings are examined, it is seen that the pilot managed the situation:

• Without raising their voice,
• By proposing alternative solutions,
• By using apologies and mitigating expressions,
• Without escalating the operation.

This approach is considered an exemplary case in terms of CRM (Crew Resource Management) and Threat & Error Management (TEM).

Who Was Right?

From a technical perspective:

• ATC issued an altitude it believed to be safe for its airspace.
• The pilot acted in accordance with international safety principles by refusing an altitude they could not verify on their charts.

This incident once again clarified the answer to the question, “Does ATC or the pilot have the final say?”:

Ultimately, the pilot is responsible for the safety of the aircraft.