Challenger 300
Flight Crew Flight Instructor; Flight Crew Air Transport Pilot (ATP); Flight Crew Multiengine
Flight Crew Last 90 Days 100; Flight Crew Total 3800; Flight Crew Type 800
Communication Breakdown; Confusion
Deviation - Altitude Overshoot; Deviation - Altitude Crossing Restriction Not Met; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Air Traffic Control Issued Advisory / Alert; Air Traffic Control Issued New Clearance; Flight Crew Became Reoriented
Procedure; Chart Or Publication; Human Factors
We were departing KONT. On the ground; we received our PDC which was the following message: -ATC CLEARANCE- CLR AS FILED-FILED FLIGHT PLAN-KONT POM7 DAG... @FLT DECK SAT PHON-REMARKS-CLEARED POM7 DEPCLIMB VIA SID; EXCEPT MAINTAIN 14;000DEP CONTROL 125.5SQUAWK XXXX-OTHER INFO-REQUESTED ALT: XXXPROPOSED ETD: XXXXZCLEARANCE ETD: ZAIRCRAFT: CL30/LEND OF CLEARANCEWe copied down the clearance and set 14;000 feet in the altitude alerter as that was our clearance limit. We reviewed the POM7.DAG SID to determine if there were any restrictions. There was an AT/BELOW 7;000 MSL at the POM navaid and AT/ABOVE 14;000 MSL at the SULZU intersection. We both discussed this departure at length and noted that nowhere on the chart does it give a 'Climb to and Maintain' initial altitude.' For a runway 28L/28R departure it states for an initial climb: 'Climbing right turn to 256 heading to intercept and proceed via POM-114 to POM; cross POM at or below 7;000 feet'; however there is no altitude to maintain and neither tower; nor SoCal gave us one (other than the original PDC). After reviewing the SID we determined that it does not have a 'climb to' or 'maintain' initial altitude. Since we were given a 'climb via' and also an 'except maintain 14;000 feet' we thought it was similar to the scenario when you are given a SID with altitude restrictions and ATC then clears you to a new altitude; thus negating the SID restriction. This was our plan for departure. The takeoff was uneventful and as we crossed 7;500 feet approximately 2 nm prior to POM navaid; SoCal departure advised us of the crossing restriction at POM of 7;000. At that point; we realized that the SID restriction was still assumed by ATC and we were then given a continued climb by ATC to 14;000 feet.The remainder of the flight was uneventful. We spent a lengthy debrief reviewing what we could have done different and as well as where the confusion came in. With the recent change in verbiage to use 'Climb Via' for SIDs now we were cued into it in the PDC; but we wrongly thought the additional phrase after 'Climb via the SID' of 'Except maintain 14;000' meant the SID crossing restrictions were lifted. It was further complicated by a SID that has no initial level-off altitude associated with it. This only reinforced that we thought the restrictions were lifted since it used the word 'except'. We identified this as being the similar situation when cleared off a SID with a new altitude clearance. We did not enter Class B airspace during the situation and there was no traffic near us; and we were VMC the entire time. With the 'Climb Via' phraseology being the new way of the future; I think it would behoove crews to thoroughly read the SID and know that when given a 'Climb via the SID; except...' that they should query the controller to find exactly what ATC is requesting. We wrongly diagnosed this to assume we were cleared from the restrictions of the SID AT/BELOW altitudes. If this is the standard that the FAA will be using; then they also could have helped the situation by removing the word 'EXCEPT' from the PDC and replacing it with 'MAINTAIN'. If the FAA/ATC simply said; 'Climb via the SID; MAINTAIN 14;000' then we would have done exactly what the SID stated and complied with the restrictions on the way up to 14;000. But in this case with the SID having no initial climb and maintain altitude associated with it; the word 'EXCEPT' meant to us that we were cleared directly to 14;000 since the word 'EXCEPT' would be referring to the restrictions; not the 14;000. To prevent this further; ATC should be more specific in what they want out of the SID; especially when the SID only shows AT/BELOW or AT/ABOVE restrictions because neither of those represent a hard altitude or a level-off so you have no direction other than to be above or below those restrictions. With a SID like the POM7; the PDC should state 'MAINTAIN 14;000' rather than 'EXCEPT; MAINTAIN 14;000' and the confusion goes away because you have to then look at the SID and see what the 'EXCEPTION' is. When the guidance is to change what the SID says to level off at 14;000 then I'd like to know what I should do if the 'exception' wasn't there. If this is the norm then the SID should be rewritten to include an altitude associated with the initial climb; rather than just repeating there is an AT/BELOW restriction; as that is not a required level-off. Querying the controller would have also resolved this.
[Report narrative contained no additional information].
The flight crew of a Challenger 300 departing ONT airport; misinterpreted the meaning of their clearance that stated 'Climb via the Pomona SID; except maintain 14;000.' They understood it to mean they could climb unrestricted to 14;000 feet; and disregard the 'At or below 7;000 feet' restriction crossing POM VOR. ATC caught their error and cleared them to continue their climb. The reporter's cited the ambiguity of the language employed; as easily understood to direct non-compliance with the earlier restriction.