Commercial Fixed Wing
Confusion; Training / Qualification
Deviation - Altitude Crossing Restriction Not Met; Deviation - Altitude Overshoot; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Clearance
Air Traffic Control Issued New Clearance; Air Traffic Control Issued Advisory / Alert; Flight Crew Became Reoriented; Flight Crew Returned To Clearance
Human Factors; Procedure
I was on my fourth IOE leg; and my fourth flight (second domestic) since January. Our PDC included the BNDTO2 RNAV SID. We discussed that the top altitude on the SID is 4;000 despite higher published altitudes on the SID. We were prepared to fly the SID correctly. Upon departure we were actually issued a heading to fly instead of the SID. After a couple of minutes we were cleared to proceed direct to SCAMM; and subsequently climb via the BNDTO2 departure except maintain 15;000. I was pilot flying and the Captain properly read back the clearance verbatim; I verified verbally (there was an FAA maintenance guy on the jumpseat who was not a pilot; and he didn't say much the entire flight) and confirmed that the captain actually set 15;000 in the ALT window. The flight director (I was hand flying still) had just captured 4;000; which was set in the ALT window from takeoff; so after 15;000 was set I pushed the button to get the FD into VNAV SPEED mode from VNAV ALT. After I did that and began the climb; the Captain commented 'Now that you've been cleared to 15;000 you can delete that restriction at SCAMM.' This was actually an erroneous statement; but I missed the error and pushed the ALT button again; deleting the 'At or below 5;000 FT' restriction at SCAMM from the legs page. I had just reviewed the new Climb/Descend VIA procedures the previous night; and thought I had understood it. As I understood it at the time; the word MAINTAIN in the climb clearance meant to climb unrestricted to the assigned altitude. Passing 6;700 FT; Departure called and told us to maintain 6;000. The Captain informed them we were climbing past 6;700 and would descend back to 6;000. We actually reached about 7;000 before the climb was arrested and we began to descend. The Controller informed us of a possible pilot deviation and passed us a number to call when we arrived. At this point; I still believed that the problem had been that the Controller had issued us an erroneous altitude; but that we had complied with all his clearances. As we discussed the matter after level off; we determined that we had actually miss-applied the climb-VIA rules and that we were; in fact; supposed to comply with the intermediate altitude restrictions on the way to 15;000 FT. I've only been given a climb VIA clearance maybe once or twice before this; and never had the altitudes changed during the flight; so even though I had just read the rules the night before; I was not as clear as I thought I was on the actual terminology. After the [computer training] segment; I had understood the key to be the word maintain. I believed; erroneously; that if I heard the word maintain that this was a clearance to climb unrestricted. It seems like the terminology is extremely similar between 'Climb VIA SID except maintain (altitude)' and 'Cleared for the SID climb and maintain (altitude)'. This presents the pilot; in a high-workload situation (on departure; changing configurations; multiple heading changes; performing direct-to functions on the FMS; etc.; not to mention flying the plane) with a challenge to listen for the key word in a clearance to determine a vastly different procedural outcome. This seems to me to be an unnecessary threat; when the intent of the wording could be much clearer by changing the terminology. For example using 'climb unrestricted' instead of 'climb and maintain' or some phraseology that is significantly different from the 'climb VIA except maintain.' In addition; for crews that routinely fly internationally; the fact that these procedures are different from the ICAO rules adds another threat in that the crewmember has to remember which wording means what not only in the U.S.; but differs depending on which country the flight is currently operating in. I tried to go back to review the segment on this; but it's not available for review after the course is completed. Having reviewed the pilot bulletins on this subject; the Flight Operations Manual (FOM) and the Aeronautical Information Manual (AIM); I believe I now understand the intent of the new wording. That is; when the terminology 'climb/descend via' is used; all altitude restrictions on the procedure (in the USA) are to be adhered to. When the terminology is 'cleared the SID/Arrival; climb/descend and maintain...' then all restrictions are deleted. While this seems simple now; it seems it took a lot of reading to get my head around it; and I'm still convinced we've introduced a significant threat unnecessarily by using such similar terminology to arrive at such different outcomes. I'd be interested to know what the rate of deviations is since we started using these new procedures.
A flight crew misunderstood a clearance to climb via an RNAV SID and maintain 15;000 FT. The clearance is interpreted to mean climb unrestricted to 15;000 FT which is not correct.