This is a little used and little understood clearance that can help when a controller’s workload is high. A cruise clearance is effectively an approach clearance and you should issue it at the same time you’d normally issue an approach clearance. It authorizes the pilot to fly the instrument approach of his choice and also authorizes a visual approach at an airport with or without an IAP. It gives the pilot a great deal of flexibility and, because of this, requires the controller to be able to protect a large amount of airspace. It’ll probably never be useful at LAX, but if you’re clobbered with arrivals at LAX and you have one aircraft inbound to CRQ, it’s a way to reduce your workload. We’ll look at two examples, one to CRQ (an airport with an IAP) and another to BNG, which has no published IAP.
At an airport with an IAP, the rules for issuing a cruise clearance are the same as they are for an IAP clearance under section 4-8. If the pilot is on a route with a published minimum altitude, you can just say “cruise 5000.” If they are not on a route with a published minimum altitude (i.e. direct to a fix), then a crossing altitude is needed. Assuming XYZ is an initial approach fix, the clearance could be “cross XYZ at/above 5000, cruise 6000.” So, let’s assume you have an aircraft inbound to CRQ at 9000 from the NW which has been cleared direct OCN. Say you’re busy working numerous aircraft elsewhere and don’t want to worry about the CRQ arrival. You could just say, “cross OCN at/above 3000, cruise 9000.” The pilot could descend at his discretion and execute the ILS, RNAV, or VOR approach; if the pilot gets the airport in sight he could also choose to fly a visual approach. Remember that this clearance gives the pilot a great deal of leeway, so make sure that he won’t be a factor for other aircraft you’re working. The cruise clearance is very similar to “cleared approach.” Using the above example, you could say “cross OCN at/above 3000, cleared approach.” The difference is that “cleared approach” requires that an IAP be flown and doesn’t permit a visual approach. So if the pilot wanted a visual approach in this case he’d have to call you back and request a visual approach clearance.
BNG can be a challenging airport because of the MVAs and MEAs in the area (it’s also challenging because it’s right on the border of ONT_APP and PSP_APP). The MVA above the airport is 10,000’; it is possible to get an aircraft overhead at 9500’ if he’s established on V388. Ideally we’d like to let the pilot start down as soon as he desires and the cruise clearance allows him to do that at his discretion. At an airport like BNG, since no IAP is available, no crossing altitude is needed for the cruise clearance because of this portion of .65 4-5-7: “When issuing a cruise clearance to an airport which does not have a published instrument approach, a cruise clearance without a crossing restriction may be issued.” Keep in mind that the altitude you issue in the cruise clearance must comply with the applicable MVA or MEA. So, let’s assume that the aircraft is assigned 11,000’ established on V388. All you have to say is “cruise 11,000.” This authorizes the pilot to immediately descend to 9500’ since that’s the MEA of the airway beyond ACINS. After that, it’s totally up to the pilot to determine the minimum IFR altitude (MIA) and he can descend at his discretion based on his determination of that MIA. Note that, with a cruise clearance, the controller has no role in the determination of the MIA, it’s totally up to the pilot. Since the cruise clearance acts as an approach clearance, it wouldn’t be necessary to issue a visual approach clearance. Keep in mind, with a cruise clearance the pilot can climb back to the altitude in the cruise clearance at any time (unless he verbally reports leaving an altitude). It’s really pretty straight-forward and the responsibility rests with the pilot to execute the descent. If you didn’t have the option of the cruise clearance, the lowest you could get the pilot is the 9500’ MEA of the airway and hope he could see the airport for a visual approach.
{Reference: P/CG “Cruise”}