When is it permitted to 'lower oneself' or 'come down' on the STAR, following a clearance?
In the world of aviation, Standard Terminal Arrival Procedures (STARs) play a crucial role in managing inbound IFR traffic efficiently. One of the key aspects of STARs is the "descend via" clearance, a directive that instructs pilots to descend while adhering to published altitude restrictions and speed constraints on the STAR.
When a pilot receives a "descend via [STAR name]" clearance, they are authorized to initiate the descent immediately, but the descent must strictly follow the altitude (and speed) restrictions depicted on the STAR chart. This means the pilot must comply with any step-down fixes, crossing altitudes, and speed limits published on the STAR, ensuring a stabilized and predictable descent path towards the approach phase.
For instance, if you were flying a regional jet approaching Chicago O'Hare from the Northwest at FL180, and ATC cleared you to descend via the TEJAS 4 Arrival, you would need to respect the published altitude restrictions on the STAR, including crossing the Corpus Christie VOR at an assigned altitude and descending to the specified altitude at each subsequent fix.
It's important to note that the "descend via" clearance is more restrictive and procedural than a general descent clearance. This ensures terrain clearance, noise abatement, and orderly sequencing of arriving traffic. For example, if you were cleared to FALLS (FAH) to "descend via" the MADII 4 arrival, the controller must issue you a crossing restriction at FAH.
In addition, pilots should not descend earlier than the STAR’s initial or published fix altitude restrictions unless specifically cleared by ATC. If no altitude is depicted at the fix you've been cleared to along a STAR, ATC is required to assign you a crossing altitude. On the MADII 4 STAR, for example, the next fix, CHDRR, must be crossed at 14,000 feet MSL.
In conclusion, the "descend via" clearance empowers the pilot to begin the descent immediately but mandates strict adherence to the STAR’s altitude restrictions until reaching the cleared final approach altitude. This operational detail is essential for safe and efficient air traffic management.
- In the aviation industry, the Standard Terminal Arrival Procedures (STARs) are vital for managing inbound IFR traffic efficiently during flight.
- When a pilot gets a "descend via [STAR name]" clearance, they are allowed to start the descent immediately, but the descent must follow the published altitude and speed restrictions on the STAR chart.
- For instance, a pilot flying a regional jet towards Chicago O'Hare from the Northwest at FL180, upon receiving a "descend via TEJAS 4 Arrival" clearance, must respect the altitude restrictions on the STAR, such as crossing the Corpus Christie VOR at a specified altitude.
- The "descend via" clearance is more restrictive and procedural than a general descent clearance, ensuring terrain clearance, noise abatement, and orderly sequencing of arriving traffic.
- For example, if a pilot was cleared to FALLS (FAH) to "descend via" the MADII 4 arrival, the controller must issue a crossing restriction at FAH.
- Pilots should not descend earlier than the STAR’s initial or published fix altitude restrictions unless specifically cleared by ATC.
- If no altitude is depicted at the fix a pilot is cleared to along a STAR, ATC is required to assign a crossing altitude, such as at the next fix, CHDRR, on the MADII 4 STAR, which must be crossed at 14,000 feet MSL.
- Adhering to the "descend via" clearance's strict altitude restrictions is crucial for safe and efficient air traffic management throughout transportation by air.
